ORCID Profile
0000-0003-2353-1640
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Publisher: Elsevier BV
Date: 04-1993
DOI: 10.1016/0169-4758(93)90177-H
Abstract: For many parasites, the interaction between the immunogenicity of the parasite and the immunological response of the host is a dynamic equilibrium that allows both to survive, albeit often with severe consequences for the host. Vaccines, if intended as a means of parasite control, are unlikely to be generally successful if they do no more than mimic an immunological equilibrium that would be reached after natural exposure to the parasites. The situation must be tipped in favour of the host. It has been difficult to find ways around this impasse. One approach has been receiving practical attention over recent years, an approach that Peter Willadsen, Craig Eisemann and Ross Tellam have called vaccination against 'concealed' antigens.
Publisher: Springer Science and Business Media LLC
Date: 13-11-2012
Abstract: We have recently described a method for the construction of an informative gene expression correlation landscape for a single tissue, longissimus muscle (LM) of cattle, using a small number (less than a hundred) of erse s les. Does this approach facilitate interspecies comparison of networks? Using gene expression datasets from LM s les from a single postnatal time point for high and low muscling sheep, and from a developmental time course (prenatal to postnatal) for normal sheep and sheep exhibiting the Callipyge muscling phenotype gene expression correlations were calculated across subsets of the data comparable to the bovine analysis. An “Always Correlated” gene expression landscape was constructed by integrating the correlations from the subsets of data and was compared to the equivalent landscape for bovine LM muscle. Whilst at the high level apparently equivalent modules were identified in the two species, at the detailed level overlap between genes in the equivalent modules was limited and generally not significant. Indeed, only 395 genes and 18 edges were in common between the two landscapes. Since it is unlikely that the equivalent muscles of two closely related species are as different as this analysis suggests, within tissue gene expression correlations appear to be very sensitive to the s les chosen for their construction, compounded by the different platforms used. Thus users need to be very cautious in interpretation of the differences. In future experiments, attention will be required to ensure equivalent experimental designs and use cross-species gene expression platform to enable the identification of true differences between different species.
Publisher: Proceedings of the National Academy of Sciences
Date: 12-1989
Abstract: Glycoproteins located on the luminal surface of the plasma membrane of tick gut epithelial cells, when used to vaccinate cattle, are capable of stimulating an immune response that protects cattle against subsequent tick infestation. One such tick gut glycoprotein, designated Bm86, has been purified to homogeneity and the amino acid sequences of peptide fragments generated by endoproteinase Lys-C digestion have been determined. We report here the isolation and characterization of a cDNA that encodes Bm86. The nucleotide sequence of the cDNA contains a 1982-base-pair open reading frame and predicts that Bm86 contains 650 amino acids including a 19-amino acid signal sequence and a 23-amino acid hydrophobic region adjacent to the carboxyl terminus. The main feature of the deduced protein sequence is the repeated pattern of 6 cysteine residues, suggesting the presence of several epidermal growth factor-like domains. A fusion protein consisting of 599 amino acids of Bm86 and 651 amino acids of beta-galactosidase was expressed in Escherichia coli as inclusion bodies. Ticks engorging on cattle vaccinated with these inclusion bodies were significantly damaged as a result of the immune response against the cloned antigen.
Publisher: Elsevier BV
Date: 12-1980
DOI: 10.1016/0301-4622(80)80007-X
Abstract: The osmotic behavior of gels derived from polyacrylamide has been measured in order to establish the validity of assuming linear concentration dependence of bead shrinkage upon osmotic pressure in quantitative studies of reversibly associating solutes by gel chromatography on Bio-Gel. The concentration dependence of elution volume predicted with due allowance for this osmotic shrinkage yields theoretical curves that provide good descriptions of experimental results obtained in chromatography of alpha-chymotrypsin on Bio-Gel P-30 equilibrated with acetate-chloride buffer, pH 3-86, 10.20 and also of bacterial alpha-amylase on Bio-Gel P-150 equilibrated with 0.10 M NaCl-0.015 M calcium acetate-0.010 M EDTA, pH 7.0. For the former system the osmotic effect has negligible consequences on the quantitative interpretation of the results. With the alpha-amylase system, however, consideration of the osmotic effect is necessary to obtain even a qualitative indication of the existence of the monomer-dimer equilibrium.
Publisher: Elsevier BV
Date: 19-08-1987
DOI: 10.1016/0167-4889(87)90155-8
Abstract: Recent studies have demonstrated that murine lymphocytes express specific cell-surface receptors for a range of sulfated polysaccharides. In order to determine whether polysaccharide binding induces transmembrane signaling, the effects of sulfated polysaccharides on the free intracellular calcium ion concentration [( Ca2+]i) of mouse thymocytes and spleen cells were determined. Cells were loaded with Indo-I, a fluorescent indicator of calcium ion concentration. The validity and limitations in the use of this indicator in the determination of [Ca2+]i are documented. Dextran sulfate (Mn = 500,000), iota-carrageenan, lambda-carrageenan and kappa-carrageenan all cause relatively large changes in the [Ca2+]i of thymocytes (change in [Ca2+]i greater than 50 nM). Of these, dextran sulfate (Mn = 500,000) always had the greatest effect on [Ca2+]i. Smaller responses were obtained with heparin and dextran sulfate (Mn = 5000), while no response was obtained with chondroitin 4-sulfate, chondroitin 6-sulfate, pentosan sulfate or fucoidin. This response pattern (with the exception of fucoidin and pentosan sulfate) corresponds with the expression of thymocyte receptors for these polysaccharides. The increase in [Ca2+]i caused by the sulfated polysaccharides requires extracellular Ca2+ ions however, it is unlikely that voltage-dependent ion channels are involved in these responses. In contrast to thymocytes, although spleen cells express receptors for sulfated polysaccharides, they were unresponsive to all of the sulfated polysaccharides tested, suggesting a basic difference between thymocytes and peripheral T and B lymphocytes in their response to the binding of sulfated polysaccharides.
Publisher: Elsevier BV
Date: 04-1989
DOI: 10.1016/0968-0004(89)90142-4
Abstract: The amino acid sequences of several actin regulatory proteins have recently been determined. Do these proteins function by mimicking actin-actin interaction sites?
Publisher: American Chemical Society (ACS)
Date: 30-07-1985
DOI: 10.1021/BI00337A029
Abstract: The CaCl2 concentration dependence of the rate of actin filament elongation and of the actin monomer concentration at steady state with actin polymer (the critical actin concentration) has been investigated. A relative rate of actin filament elongation from actin polymer intermolecularly cross-linked with N,N'-p-phenylenebis(maleimide) showed a sigmoidal dependence on the concentration of CaCl2 used to induce actin polymerization. This result is shown to be consistent with a model in which only actin monomer containing five equivalently bound Ca2+ ions (Ka = 2 mM-1) is capable of addition to actin polymer. A relative dissociation rate constant for actin monomer removal from polymer was calculated from the product of the critical actin concentration and the relative elongation rate constant and was found to be virtually independent of CaCl2 concentration. The relationship between Ca2+ binding sites on actin and the CaCl2 concentration dependence of the kinetics of actin filament elongation is discussed.
Publisher: Elsevier BV
Date: 06-1996
DOI: 10.1016/0020-7519(96)00035-5
Abstract: The larvae of the fly Lucilia cuprina excrete or secrete a chymotrypsia (LCTb) onto the skin of sheep to facilitate the establishment of the larval infestation. A combination of immunoblotting and RT-PCR approaches has established that this protease is also a gut digestive protease. LCTb is synthesized primarily in the cardia, a small highly specialized organ located at the anterior end of the midgut and by midgut cells. There is also some expression by the hindgut but no expression by salivary glands. Excretion of LCTb with waste products or regurgitation of the gut contents of the larvae may explain how this protease is transferred from the larval gut onto ovine skin. LCTb is first expressed in eggs and constitutively expressed throughout each larval instar, but is not expressed in pupae or adult flies. It is concluded that LCTb could be involved in the establishment of larvae on sheep skin as well as acting as a general gut digestive enzyme.
Publisher: Elsevier BV
Date: 08-1994
DOI: 10.1016/0020-7519(94)90132-5
Abstract: Sheep were vaccinated with two purified serine proteases, LCT25a and LCT25b, isolated from the secretory and excretory material from first instar larvae of Lucilia cuprina. The immunization produced a strong antibody response to LCT25b and a weaker response to LCT25a as measured by ELISA. However, neither protease induced an ovine immune response which affected the development of first instar larvae growing on sera derived from these sheep. Further, direct in vivo bioassays of larval growth on the backs of vaccinated sheep also indicated a lack of induction of an immune response which prevented establishment of the larvae. Sera from unvaccinated sheep which had previous experience of blowfly strike, in general, strongly recognised the serine protease LCT25b. It was concluded from all of these results that serine proteases from the secretory and excretory material of L. cuprina are unlikely to be effective antigens in a vaccine designed to protect sheep from blowfly strike.
Publisher: Springer Science and Business Media LLC
Date: 12-2011
Abstract: In livestock populations the genetic contribution to muscling is intensively monitored in the progeny of industry sires and used as a tool in selective breeding programs. The genes and pathways conferring this genetic merit are largely undefined. Genetic variation within a population has potential, amongst other mechanisms, to alter gene expression via cis- or trans-acting mechanisms in a manner that impacts the functional activities of specific pathways that contribute to muscling traits. By integrating sire-based genetic merit information for a muscling trait with progeny-based gene expression data we directly tested the hypothesis that there is genetic structure in the gene expression program in ovine skeletal muscle. The genetic performance of six sires for a well defined muscling trait, longissimus lumborum muscle depth, was measured using extensive progeny testing and expressed as an Estimated Breeding Value by comparison with contemporary sires. Microarray gene expression data were obtained for longissimus lumborum s les taken from forty progeny of the six sires (4-8 progeny/sire). Initial unsupervised hierarchical clustering analysis revealed strong genetic architecture to the gene expression data, which also discriminated the sire-based Estimated Breeding Value for the trait. An integrated systems biology approach was then used to identify the major functional pathways contributing to the genetics of enhanced muscling by using both Estimated Breeding Value weighted gene co-expression network analysis and a differential gene co-expression network analysis. The modules of genes revealed by these analyses were enriched for a number of functional terms summarised as muscle sarcomere organisation and development, protein catabolism (proteosome), RNA processing, mitochondrial function and transcriptional regulation. This study has revealed strong genetic structure in the gene expression program within ovine longissimus lumborum muscle. The balance between muscle protein synthesis, at the levels of both transcription and translation control, and protein catabolism mediated by regulated proteolysis is likely to be the primary determinant of the genetic merit for the muscling trait in this sheep population. There is also evidence that high genetic merit for muscling is associated with a fibre type shift toward fast glycolytic fibres. This study provides insight into mechanisms, presumably subject to strong artificial selection, that underpin enhanced muscling in sheep populations.
Publisher: Elsevier BV
Date: 03-2008
DOI: 10.1111/J.1432-0436.2007.00208.X
Abstract: The callipyge mutation in sheep in the form of the paternal heterozygote results in skeletal muscle hypertrophy, which is most pronounced in the hindquarters. Overexpression of one of the genes in the region of the causative single-nucleotide polymorphism, Dlk1, is postulated to be a primary cause of the muscle hypertrophy although the mechanism is not clear. This study examined the expression of Dlk1 mRNA and its encoded protein in skeletal muscles of callipyge and wild-type sheep. The muscles examined included those that demonstrate hypertrophy in callipyge sheep as well as an unaffected muscle. The expression pattern of Dlk1 protein in these muscles was also measured over a developmental time course ranging from 80 days of gestation to 12 weeks after birth. Quantitative reverse transcription-polymerase chain reaction demonstrated that Dlk1 mRNA was significantly increased in affected, but not unaffected, muscles from callipyge sheep at 120 days of gestation through to 12 weeks of age. Immuno-localization of Dlk1 was pronounced in the interstitial connective tissue of fetal muscle but was less intense at later ages. No clear difference in Dlk1 immuno-localization was noted between genotypes in the fetal s les. Strong myofiber-specific Dlk1 immuno-localization was observed in hypertrophied callipyge muscles at 12 weeks of age. This staining was exclusively associated with fast type II myofibers and these had a significantly larger mean cross-sectional area, compared with fast type II myofibers in control sheep that did not overexpress Dlk1. In addition, Dlk1 immuno-localization was associated with a sub-population of Pax7-positive mononucleated cells in all skeletal muscles examined during fetal development and at birth, but this was not apparent at 12 weeks. There were no genotype-dependent alterations in the mRNA expression patterns of a number of promyogenic transcription factors indicating that the callipyge mutation was not affecting muscle cell differentiation per se. We postulate that Dlk1 is implicated in the commitment and/or proliferation of fetal myoblasts as well as in the maintenance of hypertrophy in fully differentiated myofibers.
Publisher: Elsevier BV
Date: 12-2000
DOI: 10.1016/S0965-1748(00)00097-7
Abstract: The gut of most insects is lined with a peritrophic matrix that facilitates the digestive process and protects insects from invasion by micro-organisms and parasites. It is widely accepted that the matrix is composed of chitin, proteins and proteoglycans. Here we critically re-examine the chitin content of the typical type 2 peritrophic matrix from the larvae of the fly Lucilia cuprina using a range of techniques. Many of the histochemical and biochemical techniques indicate the presence of chitin, although they are often adversely influenced by the presence of highly glycosylated proteins, a principal component of the matrix. The alkali-stable fraction, which is used as an indicator of the maximum chitin content in a biological s le, is only 7.2% of the weight of the matrix. Larvae fed on the potent chitin synthase inhibitor polyoxin D or the chitin-binding agent Calcofluor White, showed strong concentration-dependent inhibition of larval weight and survival but no discernible effects on the matrix structure. A bacterial endochitinase fed to larvae had no effect on larval growth and no observable effect in vitro on the structure of isolated peritrophic matrix. RT-PCR did not detect a chitin synthase mRNA in cardia, the tissue from which PM originates. It is concluded that chitin is a minor structural component of the type 2 peritrophic matrix of this insect.
Publisher: American Physiological Society
Date: 12-2018
DOI: 10.1152/AJPREGU.00391.2017
Abstract: Experimental studies that are relevant to human pregnancy rely on the selection of appropriate animal models as an important element in experimental design. Consideration of the strengths and weaknesses of any animal model of human disease is fundamental to effective and meaningful translation of preclinical research. Studies in sheep have made significant contributions to our understanding of the normal and abnormal development of the fetus. As a model of human pregnancy, studies in sheep have enabled scientists and clinicians to answer questions about the etiology and treatment of poor maternal, placental, and fetal health and to provide an evidence base for translation of interventions to the clinic. The aim of this review is to highlight the advances in perinatal human medicine that have been achieved following translation of research using the pregnant sheep and fetus.
Publisher: Elsevier BV
Date: 09-2001
Publisher: Wiley
Date: 11-01-2007
DOI: 10.1111/J.1365-2052.2006.01562.X
Abstract: The callipyge mutation causes postnatal muscle hypertrophy in heterozygous lambs that inherit a paternal callipyge allele (+/CLPG). Our hypothesis was that the up-regulation of one or both of the affected paternally expressed genes (DLK1 or PEG11) initiates changes in biochemical and physiological pathways in skeletal muscle to induce hypertrophy. The goal of this study was to identify changes in gene expression during the onset of muscle hypertrophy to identify the pathways that are involved in the expression of the callipyge phenotype. Gene expression was analysed in longissimus dorsi total RNA from lambs at 10, 20, and 30 days of age using the Affymetrix Bovine Expression Array. An average of 40.6% of probe sets on the array was detected in sheep muscle. Data were normalized and analysed using a two-way anova for genotype and age effects with a false discovery rate of 0.10. From the anova, 13 genes were significant for the effect of genotype and 13 were significant for effect of age (P 0.10). Of the 13 genes indicating an effect of genotype, quantitative PCR assays were developed for all of them and tested on a larger group of animals from 10 to 200 days of age. Nine genes had significantly elevated transcript levels in callipyge lambs. These genes included phosphofructokinase, a putative methyltransferase protein, a cAMP phosphodiesterase, and the transcription factor DNTTIP1.
Publisher: Springer Science and Business Media LLC
Date: 02-06-2008
Abstract: Mastitis in dairy cattle results from infection of mammary tissue by a range of micro-organisms but principally coliform bacteria and Gram positive bacteria such as Staphylococcus aureus . The former species are often acquired by environmental contamination while S. aureus is particularly problematic due to its resistance to antibiotic treatments and ability to reside within mammary tissue in a chronic, subclinical state. The transcriptional responses within bovine mammary epithelial tissue subjected to intramammary challenge with S. aureus are poorly characterised, particularly at the earliest stages of infection. Moreover, the effect of infection on the presence of bioactive innate immune proteins in milk is also unclear. The nature of these responses may determine the susceptibility of the tissue and its ability to resolve the infection. Transcriptional profiling was employed to measure changes in gene expression occurring in bovine mammary tissues s led from three dairy cows after brief and graded intramammary challenges with S. aureus . These limited challenges had no significant effect on the expression pattern of the gene encoding β-casein but caused coordinated up-regulation of a number of cytokines and chemokines involved in pro-inflammatory responses. In addition, the enhanced expression of two genes, S100 calcium-binding protein A12 ( S100A12 ) and Pentraxin-3 ( PTX3 ) corresponded with significantly increased levels of their proteins in milk from infected udders. Both genes were shown to be expressed by mammary epithelial cells grown in culture after stimulation with lipopolysaccharide. There was also a strong correlation between somatic cell count, a widely used measure of mastitis, and the level of S100A12 in milk from a herd of dairy cows. Recombinant S100A12 inhibited growth of Escherichia coli in vitro and recombinant PTX3 bound to E. coli as well as C1q, a subunit of the first component of the complement cascade. The transcriptional responses in infected bovine mammary tissue, even at low doses of bacteria and short periods of infection, probably reflect the combined contributions of gene expression changes resulting from the activation of mammary epithelial cells and infiltrating immune cells. The secretion of a number of proinflammatory cytokines and chemokines from mammary epithelial cells stimulated by the bacteria serves to trigger the recruitment and activation of neutrophils in mammary tissue. The presence of S100A12 and PTX3 in milk from infected udder quarters may increase the anti-bacterial properties of milk thereby helping to resolve the mammary tissue infection as well as potentially contributing to the maturation of the newborn calf epithelium and establishment of the newborn gut microbial population.
Publisher: Elsevier BV
Date: 1981
Publisher: Elsevier BV
Date: 04-2002
DOI: 10.1016/S0304-4017(01)00648-3
Abstract: Immunological control of cutaneous myiasis of sheep caused by Lucilia cuprina larvae has been an elusive goal. Antibody to antigens derived from the peritrophic membrane can stunt or kill larvae in a dose dependent fashion. Thus efficacy of vaccines employing these antigens may be limited by the amount of antibody in skin available for ingestion by larvae. The potential for elevating antibody concentrations in skin by intradermal immunisation with the recombinant peritrophic membrane antigens peritrophin-44, peritrophin-48 and peritrophin-95 was therefore examined. Using within-animal comparisons, specific antibody was significantly higher in skin transudates from locally immunised sites than from adjacent adjuvant control sites. It was concluded that cutaneous immunisation may assist immunological control of blowfly larvae.
Publisher: Elsevier BV
Date: 03-1998
DOI: 10.1016/S0020-7519(97)00197-5
Abstract: Whole first-instar Lucilia cuprina larvae were homogenised and sequentially extracted with a series of buffers of progressively more severe solubilising power. The final extract, using a buffer containing 6 M-urea, was fractionated by preparative isoelectric focussing. At each step in this process, protein fractions were tested in sheep vaccination trials for their ability to induce immune responses affecting the growth of L. cuprina larvae which fed on the sera from vaccinated sheep. One isoelectric focussing fraction (pH 5.9-6.7) containing a number of larval proteins induced an immune response which inhibited the growth of larvae by a mean of 84 +/- 7% in an in vitro feeding bioassay. The recovery of larvae after feeding on sera from sheep vaccinated with this fraction was significantly reduced by 35 +/- 13%. This antilarval effect was shown to be mediated by ingested ovine antibodies. Immunofluorescence and immunogold localisations showed that the immune response was directed at proteins from the larval peritrophic membrane, larval cuticle and, to lesser extent, basement membranes and microvilli of digestive epithelial cells. Electron microscopic examination of larvae feeding on sera from sheep vaccinated with this fraction showed that the normally semi-permeable peritrophic membrane was blocked on the luminal side by an electron-lucent layer of undefined composition. It is postulated that this layer prevents nutrients from moving from the gut to the underlying digestive epithelial cells, thereby starving the larvae. The sera from sheep vaccinated with another isoelectric focussing fraction (pH 3.4-5.5) reduced the mean larval weight by 56 +/- 13% without significant effects on larval survival.
Publisher: American Physiological Society
Date: 03-2020
DOI: 10.1152/PHYSIOLGENOMICS.00092.2019
Abstract: There are critical molecular mechanisms that can be activated to induce myocardial repair, and in humans this is most efficient during fetal development. The timing of heart development in relation to birth and the size/electrophysiology of the heart are similar in humans and sheep, providing a model to investigate the repair capacity of the mammalian heart and how this can be applied to adult heart repair. Myocardial infarction was induced by ligation of the left anterior descending coronary artery in fetal (105 days gestation when cardiomyocytes are proliferative) and adolescent sheep (6 mo of age when all cardiomyocytes have switched to an adult phenotype). An ovine gene microarray was used to compare gene expression in sham and infarcted (remote, border and infarct areas) cardiac tissue from fetal and adolescent hearts. The gene response to myocardial infarction was less pronounced in fetal compared with adolescent sheep hearts and there were unique gene responses at each age. There were also region-specific changes in gene expression between each age, in the infarct tissue, tissue bordering the infarct, and tissue remote from the infarction. In total, there were 880 genes that responded to MI uniquely in the adolescent s les compared with 170 genes in the fetal response, as well as 742 overlap genes that showed concordant direction of change responses to infarction at both ages. In response to myocardial infarction, there were specific changes in genes within pathways of mitochondrial oxidation, muscle contraction, and hematopoietic cell lineages, suggesting that the control of energy utilization and immune function are critical for effective heart repair. The more restricted gene response in the fetus may be an important factor in its enhanced capacity for cardiac repair.
Publisher: Frontiers Media SA
Date: 2012
Publisher: Wiley
Date: 22-11-2011
Publisher: American Physiological Society
Date: 02-2007
DOI: 10.1152/PHYSIOLGENOMICS.00121.2006
Abstract: The callipyge mutation in sheep results in postnatal skeletal muscle hypertrophy in the pelvic limbs and loins with little or no effect on anterior skeletal muscles. Associated with the phenotype are changes in the expression of a number of imprinted genes flanking the site of the mutation, which lies in an intergenic region at the telomeric end of ovine chromosome 18. The manner in which these local changes in gene expression are translated into muscle hypertrophy is not known. Microarray-based transcriptional profiling was used to identify differentially expressed genes in longissimus dorsi skeletal muscle s les taken at birth and 12 wk of age from callipyge and wild-type sheep. The phenotype was only expressed at the latter developmental time and associated with decreased type 1 fibers (slow oxidative) and a shift toward type IIx and IIb fibers (fast-twitch glycolytic). We have identified 131 genes in the s les taken at 12 wk of age that were differentially expressed as a function of genotype but not due to the fiber type changes. The gene expression changes occurring as a function of genotype in the s les taken at birth indicated that the transcriptional framework underpinning the phenotype was emerging prior to expression of the phenotype. Eight genes were differentially expressed as a function of genotype at both developmental times. A model is proposed describing a core network of genes and histone epigenetic modifications that is likely to underpin the fiber type changes and muscle hypertrophy characteristic of callipyge sheep.
Publisher: Elsevier BV
Date: 03-1990
DOI: 10.1016/0014-4827(90)90135-W
Abstract: The relative amounts of intracellular gelsolin were determined in a number of human somatic cell hybrids and parental cell lines which greatly differ in their microfilament organizations. In contrast to the disruptive effect of gelsolin on actin filament formation in vitro, there is a correlation between the degree of microfilament organization and the amount of gelsolin within these cell lines.
Publisher: American Physiological Society
Date: 05-2008
DOI: 10.1152/AJPREGU.00787.2007
Abstract: Placental restriction (PR) of fetal growth results in a low birth weight and an increased visceral fat mass in postnatal life. We investigated whether PR alters expression of genes that regulate adipogenesis [IGF1, IGF1 receptor (IGF1R), IGF2, IGF2R, proliferator-activated receptor-γ, retinoid-X-receptor-α], adipocyte metabolism (lipoprotein lipase, G3PDH, GAPDH) and adipokine signaling (leptin, adiponectin) in visceral adipose tissue before birth. PR was induced by removal of the majority of endometrial caruncles in nonpregnant ewes before mating. Fetal blood s les were collected from 116 days gestation, and perirenal visceral adipose tissue (PAT) was collected from PR and control fetuses at 145 days. PAT gene expression was measured by quantitative RT-PCR. PR fetuses had a lower weight (PR 2.90 ± 0.32 kg control, 5.12 ± 0.24 kg P 0.0001), mean gestational arterial Po 2 ( P 0.0001), plasma glucose ( P 0.01), and insulin concentrations ( P 0.02), than controls. The expression of IGF1 mRNA in PAT was lower in the PR fetuses (PR, 0.332 ± 0.063 control, 0.741 ± 0.083 P 0.01). Leptin mRNA expression in PAT was also lower in PR fetuses (PR, 0.077 ± 0.009 control, 0.115 ± 0.013 P 0.05), although there was no difference in the expression of other adipokine or adipogenic genes in PAT between PR and control fetuses. Thus, restriction of placental and hence, fetal substrate supply results in decreased IGF1 and leptin expression in fetal visceral adipose tissue, which may alter the functional development of the perirenal fat depot and contribute to altered leptin signaling in the growth-restricted newborn and the subsequent emergence of an increased visceral adiposity.
Publisher: American Dairy Science Association
Date: 10-2009
Abstract: The bovine Muc1 protein is synthesized by mammary epithelial cells and shed into milk as an integral component of the milk fat globule membrane however, the structure and functions of this mucin, particularly in relation to lactation, are poorly defined. The objectives of this investigation were to investigate the Muc1 gene and protein structures in the context of lactation and to test the hypothesis that Muc1 has a role in innate immune defense. Polymerase chain reaction analysis of genomic DNA from 630 cattle revealed extensive polymorphism in the variable number of tandem repeats (VNTR) in the bovine Muc1 gene. Nine allelic variants spanning 7 to 23 VNTR units, each encoding 20 AA, were identified. Three alleles, containing 11, 14, and 16 VNTR units, respectively, were predominant. In addition, a polymorphism in one of the VNTR units has the potential to introduce a unique site for N-linked glycosylation. Statistical analysis indicated weak associations between the VNTR alleles and milk protein and fat percentages in a progeny-tested population of Holstein-Friesian dairy cattle. No association with somatic cell count could be demonstrated. Bovine Muc1 was purified from milk fat globule membranes and characterized. The protein was highly glycosylated, primarily with O-linked sialylated T-antigen [Neu5Ac(alpha2-3)-Gal(beta1-3)-GalNAcalpha1] and, to a lesser extent, with N-linked oligosaccharides, which together accounted for approximately 60% of the apparent mass of Muc1. Purified bovine Muc1 directly bound fluorescently labeled Escherichia coli BioParticles (Invitrogen, Mount Waverley, Australia) and inhibited their binding to bovine mammary epithelial cells grown in vitro. It was also demonstrated that the expression of Muc1 mRNA in bovine mammary epithelial cells was markedly upregulated by lipopolysaccharide. Muc1 may be a pattern recognition protein that has the capacity to sequester bacteria and prevent their attachment to epithelial surfaces by immobilizing and subsequently shedding Muc1-bound bacteria from the cell surface. It was concluded that bovine Muc1 is probably an inducible innate immune effector and an important component of the first line of defense against bacterial invasion of epithelial surfaces, particularly mammary epithelial surfaces and the neonatal gut.
Publisher: Springer Science and Business Media LLC
Date: 06-1985
DOI: 10.1038/BJC.1985.119
Abstract: The fluorescent indicator of Ca2+ concentration, quin-2, has been used to measure the concentration of free Ca2+ in the cytoplasm of tumorigenic and non-tumorigenic human somatic cell hybrids. The cell hybrids were derived from the fusion of a HeLa derivative (D98 AH2) and normal human fibroblasts. The calcium concentration of the tumorigenic cell lines was 180 +/- 7nM and the level in the non-tumorigenic cells was 136 +/- 6nM. This difference was statistically highly significant (P less than 0.001). Control experiments are reported which show that the level of 3a2+ measured is not influenced by cell density or by the concentration of quin-2-tetra-(acetoxymethyl)ester used in these experiments. The possible implications of this elevated level of cytoplasmic calcium in tumorigenic cells are discussed.
Publisher: Springer Science and Business Media LLC
Date: 25-02-2015
DOI: 10.1038/IJO.2014.34
Abstract: Recent technological advances in epigenome profiling have led to an increasing number of studies investigating the role of the epigenome in obesity. There is also evidence that environmental exposures during early life can induce persistent alterations in the epigenome, which may lead to an increased risk of obesity later in life. This paper provides a systematic review of studies investigating the association between obesity and either global, site-specific or genome-wide methylation of DNA. Studies on the impact of pre- and postnatal interventions on methylation and obesity are also reviewed. We discuss outstanding questions, and introduce EpiSCOPE, a multidisciplinary research program aimed at increasing the understanding of epigenetic changes in emergence of obesity. An electronic search for relevant articles, published between September 2008 and September 2013 was performed. From the 319 articles identified, 46 studies were included and reviewed. The studies provided no consistent evidence for a relationship between global methylation and obesity. The studies did identify multiple obesity-associated differentially methylated sites, mainly in blood cells. Extensive, but small, alterations in methylation at specific sites were observed in weight loss intervention studies, and several associations between methylation marks at birth and later life obesity were found. Overall, significant progress has been made in the field of epigenetics and obesity and the first potential epigenetic markers for obesity that could be detected at birth have been identified. Eventually this may help in predicting an in idual's obesity risk at a young age and opens possibilities for introducing targeted prevention strategies. It has also become clear that several epigenetic marks are modifiable, by changing the exposure in utero, but also by lifestyle changes in adult life, which implies that there is the potential for interventions to be introduced in postnatal life to modify unfavourable epigenomic profiles.
Publisher: Springer Science and Business Media LLC
Date: 03-10-2016
DOI: 10.1038/NN.4398
Publisher: Springer Science and Business Media LLC
Date: 22-09-2005
Abstract: Microarray transcript profiling has the potential to illuminate the molecular processes that are involved in the responses of cattle to disease challenges. This knowledge may allow the development of strategies that exploit these genes to enhance resistance to disease in an in idual or animal population. The Bovine Innate Immune Microarray developed in this study consists of 1480 characterised genes identified by literature searches, 31 positive and negative control elements and 5376 cDNAs derived from subtracted and normalised libraries. The cDNA libraries were produced from 'challenged' bovine epithelial and leukocyte cells. The microarray was found to have a limit of detection of 1 pg/μg of total RNA and a mean slide-to-slide correlation co-efficient of 0.88. The profiles of differentially expressed genes from Concanavalin A (ConA) stimulated bovine peripheral blood lymphocytes were determined. Three distinct profiles highlighted 19 genes that were rapidly up-regulated within 30 minutes and returned to basal levels by 24 h 76 genes that were up-regulated between 2–8 hours and sustained high levels of expression until 24 h and 10 genes that were down-regulated. Quantitative real-time RT-PCR on selected genes was used to confirm the results from the microarray analysis. The results indicate that there is a dynamic process involving gene activation and regulatory mechanisms re-establishing homeostasis in the ConA activated lymphocytes. The Bovine Innate Immune Microarray was also used to determine the cross-species hybridisation capabilities of an ovine PBL s le. The Bovine Innate Immune Microarray has been developed which contains a set of well-characterised genes and anonymous cDNAs from a number of different bovine cell types. The microarray can be used to determine the gene expression profiles underlying innate immune responses in cattle and sheep.
Publisher: Elsevier BV
Date: 2001
Publisher: Public Library of Science (PLoS)
Date: 30-06-2017
Publisher: Public Library of Science (PLoS)
Date: 17-06-2014
Publisher: Cambridge University Press (CUP)
Date: 29-01-2008
DOI: 10.1017/S0022029907003056
Abstract: The roles of the pro-adipogenic ligands of the transcription factor Peroxisome Proliferator Activated Receptor gamma (PPARG) in regulating innate immune responses in bovine mammary epithelial cells (bMEC) were investigated using quantitative real-time PCR. The analyses revealed that 15-deoxy-Δ 12,14 -prostaglandin J 2 (15d-PGJ 2 ) enhanced the expression of Interleukin 8 ( IL-8 ) and Chemokine (C-X-C motif ) ligand 6 ( CXCL6 ) in these cells in a dose-dependent manner. 15d-PGJ 2 also induced the expression of transcripts encoding proteins involved in oxidative stress, including Ferritin heavy chain and Superoxide dismutase 1 , as well as substantial microfilament reorganization. In contrast, synthetic PPARG agonists displayed a different and much smaller range of effects on the cells, causing down-regulation of Interleukin 1-beta , Interleukin 6 and IL-8 and increased expression of Chemokine (C-C motif ) ligand 2 ( CCL2 ) and Tumour necrosis factor alpha ( TNF α). In an independent analysis, the cells were pre-incubated with PPARG agonists followed by lipopolysaccharide stimulation. This study revealed that troglitazone increased the responsiveness of the cells to lipopolysaccharide resulting in up-regulation of Interleukin 1-beta , TNF α, IL-8 , CCL2 and CXCL6 while 15d-PGJ 2 caused down-regulation of TNF α, CCL2 and CXCL6 . These findings are relevant to understanding the anti-inflammatory potential of the PPARG ligands and underline different mechanisms of action of 15d-PGJ 2 and troglitazone in bMEC. Furthermore, the present results demonstrate that the generation of pro-inflammatory mediators can be modulated by currently available therapeutic agents and may therefore be of value in the treatment of mastitis in ruminants.
Publisher: Springer Science and Business Media LLC
Date: 2003
Abstract: There is a history of copper deficiency in grazing Omani livestock and the copper status of three economically important goat breeds, Jabal Akhdar (JA), Batina (B) and Dhofari (D) were therefore compared in October/November (cool season) and June (dry season) in a penned flock given a plentiful dietary supply of copper. In the cool season, 62 lactating does (5 JA, 12 B and 33 D), their 0-5-day-old kids (17 JA, 19 B and 22 D) and 25 dry does (17 JA, 5 B and 3 D) were blood s led. In the dry season, the does s led were either barren (15 JA, 16 B and 13 D) or pregnant (9 JA, 13 B and 33 D). The s les were analysed for total copper (TCu) and trichloroacetic acid (TCA)-soluble copper (TCA-sol Cu). There were no effects of breed on TCu or TCA-sol Cu in the cool season, the overall means being 0.75 (SE 0.049) and 0.59 (SE 0.052) mg/L. The mean TCu was low in kids at birth (0.59 mg/L) but had increased to 0.86 mg/L by 4 days of age (p < 0.001) breed differences were found (p < 0.002), the pooled values for JA, B and D being 0.77, 0.59 and 0.68 (SE 0.033-0.044) mg/L, respectively. By the dry season, the mean TCu had risen in barren does to 0.96 (0.045) mg/L but not in pregnant does (0.76 (0.047) mg/L: p < 0.002) and breed differences had emerged, the mean for D being 20% lower than those for JA and B (p < 0.05). The highest TCu values were found in the 7-month-old kids in June ( 1.17 (0.039) mg/L) but the breeds did not then differ. Some effects on TCA solubility were found but were considered unreliable. Breed effects may have been diminished by the generous supply of copper and early stage of lactation studied.
Publisher: Elsevier BV
Date: 06-2001
DOI: 10.1016/S0020-7519(01)00195-3
Abstract: The larvae of the fly Lucilia cuprina cause a cutaneous myiasis in mammalian hosts, particularly sheep. The glycoprotein, peritrophin-95, isolated from Lucilia cuprina larval peritrophic matrix, is a candidate vaccine antigen. This protein induced an immune response in vaccinated sheep that inhibited larval growth. Recombinant forms of peritrophin-95 were produced in bacteria and baculovirus-infected insect cells. The bacterial protein was not glycosylated and incorrectly folded whereas the insect cell-expressed protein was glycosylated and probably correctly folded. Sheep immunised with purified native peritrophin-95 generated strong larval growth inhibitory activity in their sera, whereas sheep immunised with either recombinant form of peritrophin-95 generated only relatively weak inhibitory activity. Ingested ovine antibodies to native peritrophin-95 mediated the anti-larval growth activity and this was independent of the presence of ovine complement. The activity was associated with IgG(1) and IgG(2) but not IgM. There were strong antibody responses to both the correctly folded native peritrophin-95 polypeptide and the oligosaccharides present on this glycoprotein. Immuno-affinity isolation of antibody to the peritrophin-95 polypeptide and antibody to peritrophin-95 oligosaccharides demonstrated that the larval growth inhibitory activity resided with both antibodies. Lectin blots and ELISA data showed substantial differences between the oligosaccharides attached to native peritrophin-95 and insect cell-expressed recombinant peritrophin-95. It was concluded that the oligosaccharides attached to native peritrophin-95 and its unique polypeptide structure are essential for the induction of larval growth inhibitory activity in the sera of sheep vaccinated with this antigen.
Publisher: Springer Science and Business Media LLC
Date: 07-2009
Publisher: Public Library of Science (PLoS)
Date: 08-01-2010
Publisher: Wiley
Date: 10-2000
DOI: 10.1046/J.1432-1327.2000.01679.X
Abstract: Chitin is a major component of the cuticle of arthropods. However, the synthesis of chitin is poorly understood. Feeding larvae of the insect Lucilia cuprina on the fungal chitin synthase competitive inhibitor, nikkomycin Z resulted in strong concentration-dependent mortality of the larvae (LD50 = 280 nM). This result demonstrates that chitin is an essential component of this insect. The complete cDNA and deduced amino-acid sequences of the first arthropod chitin synthase-like protein, LcCS-1, from the larvae of the insect L. cuprina have been determined. The cDNA sequence is 5757 bp in length and codes for a large complex protein containing 1592 amino acids (Mr = 180 717). Analysis of the whole protein sequence reveals low, but significant, similarity to yeast chitin synthases with stronger areas of conservation centred on local regions implicated in the active sites of the yeast enzymes. Strikingly, LcCS-1 contains 15-18 potential transmembrane segments, indicating that the protein is an integral membrane protein. Two alternative topographical models of LcCS-1 are described, which involve its association with either the plasma membrane or the membrane of intracellular vesicles. LcCS-1 mRNA is produced in all life stages of the insect with expression in the larval stage limited to the integument and trachea. In a third instar larva the mRNA was localized to a single layer of epidermal cells immediately underlying the procuticle region of the integument. cDNA or genomic sequences that are highly related to fragments of LcCS-1 were demonstrated in three insect orders, one arachnid and Caenorhabditis elegans, thereby attesting to the importance of this enzyme in these chitin-producing organisms. Bioinformatics has been used to deduce the gene sequence and organization of the highly homologous Drosophila melanogaster orthologue of LcCS-1, DmCS-1.
Publisher: Elsevier BV
Date: 04-1993
DOI: 10.1016/0020-7519(93)90144-N
Abstract: A culture system has been established to produce gram amounts of peritrophic membrane from larvae of the sheep blowfly, Lucilia cuprina. Peritrophic membrane obtained from this culture has been used to immunize sheep. The immunization produced an immune response which resulted in the average weight of larvae on immunized sheep being only 50% of that of larvae grown on control sheep (P < 0.05). Fractionation of the components of the peritrophic membrane followed by immunization trials showed that the protective antigen fraction comprised material that could only be solubilized by harsh agents such as 4 M-urea. Even after solubilization by 4 M-urea, the protective antigens were able to produce a protective immune response which reduced growth of larvae on immunized sheep to 55% of larvae grown on control sheep (P < 0.05). This immune response which reduced growth of the larvae did not cause gross morphological damage to the larvae.
Publisher: CSIRO Publishing
Date: 2007
DOI: 10.1071/EA06032
Abstract: The bovine genome sequence in ‘draft’ form will be complete in 2007. The availability of the sequence and very large numbers of single nucleotide polymorphisms will have profound effects on livestock production. The dairy industry is well positioned to capture the benefits of this enormous and enabling resource because of its comprehensive databases containing phenotypic and pedigree data for large numbers of animals, intense utilisation of genetics in breeding programs and efficient management of reproductive performance. The bovine genome sequence will assist in the development of novel products, especially value-added products, and markedly enhance the rate of genetic gain in the Australian dairy population. The immediate challenge facing the industry is the integration of new technological capabilities into existing breeding programs and production systems.
Publisher: Wiley
Date: 1987
DOI: 10.1007/BF02534875
Abstract: Over 4 million patients suffer nosocomial infections annually in the European Union. This study aimed to estimate the healthcare burden associated with healthcare-associated infections (HAIs) following surgery in France, and explore the potential impact of infection control strategies and interventions on the clinical and economic burden of disease. Data on the frequency of HAIs were gathered from the 2010 Programme de Médicalisation des Systèmes d'Information (PMSI), and cost data were taken from the 2009 Echelle Nationale de Coûts à Méthodologie Commune (ENCC). It was estimated that 3% of surgical procedures performed in 2010 in France resulted in infection, resulting in an annual cost of €57 892 715. Patients experiencing a HAI had a significantly increased mortality risk (4.15-fold) and an increased length of hospital stay (threefold). Scenario analysis in which HAI incidence following surgery was reduced by 8% (based on a study of the effectiveness of triclosan-coated sutures), suggested that, annually, 20 205 hospital days and €4 588 519 could be saved. Analyses of 20% and 30% reductions in incidence (based on an estimate of the number of preventable nosocomial infections) suggested that annual savings of €11 548 057 and €17 334 696, respectively, could be made. New infection control interventions which reduce HAI incidence during hospitalization for surgery have the potential to provide valuable cost savings to healthcare providers.
Publisher: Springer Science and Business Media LLC
Date: 15-06-2010
Abstract: The developmental transition between the late fetus and a newborn animal is associated with profound changes in skeletal muscle function as it adapts to the new physiological demands of locomotion and postural support against gravity. The mechanisms underpinning this adaption process are unclear but are likely to be initiated by changes in hormone levels. We tested the hypothesis that this developmental transition is associated with large coordinated changes in the transcription of skeletal muscle genes. Using an ovine model, transcriptional profiling was performed on Longissimus dorsi skeletal muscle taken at three fetal developmental time points (80, 100 and 120 d of fetal development) and two postnatal time points, one approximately 3 days postpartum and a second at 3 months of age. The developmental time course was dominated by large changes in expression of 2,471 genes during the interval between late fetal development (120 d fetal development) and 1-3 days postpartum. Analysis of the functions of genes that were uniquely up-regulated in this interval showed strong enrichment for oxidative metabolism and the tricarboxylic acid cycle indicating enhanced mitochondrial activity. Histological examination of tissues from these developmental time points directly confirmed a marked increase in mitochondrial activity between the late fetal and early postnatal s les. The promoters of genes that were up-regulated during this fetal to neonatal transition were enriched for estrogen receptor 1 and estrogen related receptor alpha cis-regulatory motifs. The genes down-regulated during this interval highlighted de-emphasis of an array of functions including Wnt signaling, cell adhesion and differentiation. There were also changes in gene expression prior to this late fetal - postnatal transition and between the two postnatal time points. The former genes were enriched for functions involving the extracellular matrix and immune response while the latter principally involved functions associated with transcriptional regulation of metabolic processes. It is concluded that during late skeletal muscle development there are substantial and coordinated changes in the transcription of a large number of genes many of which are probably triggered by increased estrogen levels. These changes probably underpin the adaption of muscle to new physiological demands in the postnatal environment.
Publisher: Public Library of Science (PLoS)
Date: 09-10-2014
Publisher: Springer Science and Business Media LLC
Date: 24-07-2014
Publisher: Springer Science and Business Media LLC
Date: 23-11-2010
Abstract: About forty human diseases are caused by repeat instability mutations. A distinct subset of these diseases is the result of extreme expansions of polymorphic trinucleotide repeats typically CAG repeats encoding poly-glutamine (poly-Q) tracts in proteins. Polymorphic repeat length variation is also apparent in human poly-Q encoding genes from normal in iduals. As these coding sequence repeats are subject to selection in mammals, it has been suggested that normal variations in some of these typically highly conserved genes are implicated in morphological differences between species and phenotypic variations within species. At present, poly-Q encoding genes in non-human mammalian species are poorly documented, as are their functions and propensities for polymorphic variation. The current investigation identified 178 bovine poly-Q encoding genes (Q ≥ 5) and within this group, 26 genes with orthologs in both human and mouse that did not contain poly-Q repeats. The bovine poly-Q encoding genes typically had ubiquitous expression patterns although there was bias towards expression in epithelia, brain and testes. They were also characterised by unusually large sizes. Analysis of gene ontology terms revealed that the encoded proteins were strongly enriched for functions associated with transcriptional regulation and many contributed to physical interaction networks in the nucleus where they presumably act cooperatively in transcriptional regulatory complexes. In addition, the coding sequence CAG repeats in some bovine genes impacted mRNA splicing thereby generating unusual transcriptional ersity, which in at least one instance was tissue-specific. The poly-Q encoding genes were prioritised using multiple criteria for their likelihood of being polymorphic and then the highest ranking group was experimentally tested for polymorphic variation within a cattle ersity panel. Extensive and meiotically stable variation was identified. Transcriptional ersity can potentially be generated in poly-Q encoding genes by the impact of CAG repeat tracts on mRNA alternative splicing. This effect, combined with the physical interactions of the encoded proteins in large transcriptional regulatory complexes suggests that polymorphic variations of proteins in these complexes have strong potential to affect phenotype.
Publisher: Wiley
Date: 27-03-2014
DOI: 10.1111/AGE.12145
Publisher: Springer Science and Business Media LLC
Date: 2007
Publisher: American Chemical Society (ACS)
Date: 11-1979
DOI: 10.1021/BI00591A009
Abstract: The binding of N-acetyl-tryptophan to the monomeric and dimeric forms of alpha-chymotrypsin in I = 0.2 acetate-chloride buffer, pH 3.86, has been studied quantitatively. Equilibrium sedimentation studies in the absence of inhibitor yielded a dimerization constant of 3.5 L/g. This value was confirmed by frontal gel chromatography of the enzyme on Bio-Gel P-30, which was also used to establish that N-acetyl-L-tryptophan binds preferentially to monomeric enzyme. From kinetic studies of competitive inhibition with N-acetyl-L-tryptophan ethyl ester as substrate, an equilibrium constant of 1300 M-1 was determined for the binding of N-acetyl-L-tryptophan to monomeric alpha-chymotrypsin. An intrinsic binding constant of 250 M-1 for the corresponding interaction with dimeric enzyme was calculated on the basis of these results and binding data obtained with concentrated (18.5 g/L) alpha-chymotrypsin. The present results refute earlier claims for exclusive binding of competitive inhibitors to monomer and also those for equivalence of inhibitor binding to monomeric and dimeric forms of alpha-chymotrypsin.
Publisher: Figshare
Date: 2011
Publisher: Figshare
Date: 2011
Publisher: Figshare
Date: 2011
Publisher: Elsevier BV
Date: 07-2005
DOI: 10.1016/J.CYTO.2005.02.010
Abstract: The objective of the present study was to characterize the innate immune responses induced by in vitro stimulation of bovine primary mammary epithelial cells (bMEC) using gram-negative lipopolysaccharide (LPS) and gram-positive lipoteichoic acid (LTA) bacterial cell wall components. Quantitative real-time PCR (qRT-PCR) was employed to examine the mRNA expression of a panel of 22 cytokines, chemokines, beta-defensins and components of the Toll-Like Receptor signaling pathway. Stimulation of bMEC with LPS for 24h elicited a marked increase in mRNA expression for IL-1beta, IL-8, TNFalpha, CXCL6 and beta-defensin while members of the Toll-Like Receptor pathway, although present, were largely unaffected. Surprisingly, stimulation of these cells with LTA for 24 h did not significantly alter the expression of these genes. A time course of the expression of IL-1beta, IL-8, TNFalpha, CXCL6 and beta-defensin was subsequently performed. The mRNA levels of all genes increased rapidly after stimulation for 2-4 h with both LPS and LTA but only the former treatment resulted in sustained responses. In contrast, the increased gene expression for LTA stimulated cells returned to resting levels after 8-16 h with the exception of beta-defensin, which remained up-regulated. The limited and unsustained cytokine response to LTA may explain why mastitis caused by gram-positive bacteria has greater potential for chronic intra-mammary infection than gram-negative infection. It was concluded that bovine mammary epithelial cells have a strong but differential capacity to mount innate immune responses to bacterial cell wall components.
Publisher: Elsevier BV
Date: 02-1999
DOI: 10.1016/S0965-1748(98)00123-4
Abstract: The peritrophic matrix (or peritrophic membrane) lines the gut of most insects at one or more stages of the life cycle. It has important roles in the facilitation of the digestive processes in the gut and the protection of the insect from invasion by microorganisms and parasites. The traditional view of the peritrophic matrix as a relatively insert sieve, composed largely of proteins and glycosaminoglycans embedded in a chitinous matrix, is under revision as more is learned about the molecular characteristics of the peritrophic matrix proteins. This review summarizes emerging knowledge of the main protein constituents of the peritrophic matrix. The availability of the first sequences of integral peritrophic matrix proteins has coincided with the explosion of information in sequence databases. It is therefore possible to examine common structural themes in this family of proteins as well as in proteins of unknown location and function from a variety of other insects, nematodes and viruses. The review concludes with speculation about the biological functions of the proteins in this matrix.
Publisher: Wiley
Date: 28-06-2018
DOI: 10.1113/JP276072
Publisher: Figshare
Date: 2011
Publisher: Figshare
Date: 2011
Publisher: Figshare
Date: 2011
Publisher: Figshare
Date: 2011
Publisher: Elsevier BV
Date: 06-1986
DOI: 10.1016/0006-291X(86)90350-5
Abstract: Climate change is predicted to result in changes in the geographic ranges and local prevalence of infectious diseases, either through direct effects on the pathogen, or indirectly through range shifts in vector and reservoir species. To better understand the occurrence of monkeypox virus (MPXV), an emerging Orthopoxvirus in humans, under contemporary and future climate conditions, we used ecological niche modeling techniques in conjunction with climate and remote-sensing variables. We first created spatially explicit probability distributions of its candidate reservoir species in Africa's Congo Basin. Reservoir species distributions were subsequently used to model current and projected future distributions of human monkeypox (MPX). Results indicate that forest clearing and climate are significant driving factors of the transmission of MPX from wildlife to humans under current climate conditions. Models under contemporary climate conditions performed well, as indicated by high values for the area under the receiver operator curve (AUC), and tests on spatially randomly and non-randomly omitted test data. Future projections were made on IPCC 4(th) Assessment climate change scenarios for 2050 and 2080, ranging from more conservative to more aggressive, and representing the potential variation within which range shifts can be expected to occur. Future projections showed range shifts into regions where MPX has not been recorded previously. Increased suitability for MPX was predicted in eastern Democratic Republic of Congo. Models developed here are useful for identifying areas where environmental conditions may become more suitable for human MPX targeting candidate reservoir species for future screening efforts and prioritizing regions for future MPX surveillance efforts.
Publisher: Elsevier BV
Date: 03-1997
DOI: 10.1016/S0020-7519(96)00174-9
Abstract: Blowfly strike is a cutaneous myiasis in sheep caused by infestations of larvae principally from the family Calliphoridae, particularly the species Lucilia cuprina and Lucilia sericata. These larval infestations cause considerable economic losses to the wool industry. Established control methods have served the industry well in the past, but there are growing deficiencies with these methods. In particular, there is widespread resistance to organophosphorus insecticides and potential difficulties associated with the presence of chemical residues derived from insecticides in wool and waste products which must be disposed of by the industry. There is also growing opposition to the radical surgical procedures used to decrease the susceptibility of sheep to blowfly strike. Consequently, there is a need for the development of alternative control measures. This review examines critically the present control methods and discusses the range of options available for the development of new control strategies. Many of the latter involve novel approaches which will strongly complement current control measures.
Publisher: Elsevier BV
Date: 2000
DOI: 10.1016/S0965-1748(99)00089-2
Abstract: The intrinsic peritrophic matrix glycoprotein, peritrophin-95, from the midgut of larvae of Lucilia cuprina can only be solubilized from the matrix using strong denaturants. This suggests that the protein has a structural role in the matrix. Consistent with this is the finding that immuno-gold and immuno-fluorescence localizations of the protein showed a uniform distribution within the peritrophic matrix. RT-PCR demonstrated that expression of peritrophin-95 mRNA was restricted to the larval cardia, a small organ located in the anterior midgut from which the type 2 peritrophic matrix originates. Immuno-blots and ELISAs demonstrated that the sera from sheep infested naturally or artificially with these larvae recognised peritrophin-95. This indicates that peritrophin-95 stimulates the ovine immune system during larval infestation even though the protein is firmly attached to the peritrophic matrix in the larval midgut and seemingly "concealed" from the ovine immune surveillance system. Analyses of larval regurgitated or excreted material by immuno-blots, immuno-affinity purification and amino-terminal sequencing demonstrated the presence of soluble monomeric peritrophin-95. These results indicate that peritrophin-95, a candidate vaccine antigen for use in sheep is not a "concealed" antigen as previously thought. The presence of soluble peritrophin-95 in the regurgitated/excreted material from larvae suggests that this protein may be involved in a maturation phase of peritrophic matrix production, a by-product of which is the excretion or regurgitation of soluble peritrophin-95.
Publisher: Figshare
Date: 2011
Publisher: Elsevier BV
Date: 02-1998
DOI: 10.1016/S0965-1748(97)00103-3
Abstract: The gut of most insects is lined with a semi-permeable peritrophic membrane (or peritrophic matrix) composed of chitin, proteoglycans and proteins. Despite the probable importance of the peritrophic membrane in facilitating the digestive process and protecting insects from invasion by micro-organisms and parasites, there has been little characterization of the specific components and their interactions within this acellular structure. Here we report the characterization of an integral peritrophic membrane glycoprotein, peritrophin-48, from the larvae of the fly Lucilia cuprina, a primary agent of cutaneous myiasis in sheep. Peritrophin-48 was purified from peritrophic membrane obtained by larval culture and its location within the peritrophic membrane determined by immuno-fluorescence and immuno-gold localizations. The cDNA coding for peritrophin-48 was cloned and sequenced. The deduced amino acid sequence codes for a protein of 375 amino acids containing an amino-terminal signal sequence followed by five similar, but non-identical domains, each approximately 65-70 amino acids in length and characterised by a specific register of six cysteines. The deduced amino acid sequence shows significant similarity to two other peritrophic membrane proteins, peritrophin-95 and peritrophin-44, from the same species. A reverse transcriptase-PCR approach indicated that there are several highly related peritrophin-48 genes expressed in each in idual. Reverse transcriptase-PCR also demonstrated the expression of peritrophin-48 in all three larval instars and adults but not pupae or eggs. Peritrophin-48 was expressed only by the cardia and by the larval midgut. A simple structural model of a basic unit of a type 2 peritrophic membrane is presented.
Publisher: Figshare
Date: 2011
Publisher: Elsevier BV
Date: 04-2015
DOI: 10.1016/J.MRREV.2015.03.003
Abstract: G-quadruplexes (G4) are highly stable tetra-stranded secondary DNA structures known to mediate gene regulation. These structures are resolved by DNA helicases and are believed to be a causal factor in the phenotype of premature ageing disorders following mutations in DNA helicase genes. The relevance of G4 structures in ageing may be further implicated by their dynamic relationship with DNA modification mechanisms. When DNA methylation and oxidation occur at the vicinity of G4 elements, they can affect the stability of G4 structures which may in turn mediate gene expression resulting in deleterious effects on genome integrity. Therefore, the influence of nutritional deficiencies or excess on oxidation and methylation mechanisms may be contributing factors affecting the stability of G4 structures and their balance in the human genome. We propose that dietary nutrients such as folate and antioxidants may play a beneficial role in reducing G4-induced DNA damage through changes in G4 structure stability. The current knowledge advocates the importance of resolving G4 structures by DNA helicases for sustained genome integrity, and the existence of stability changes in G4 structures when associated with DNA methylation and oxidation modifications.
Publisher: Public Library of Science (PLoS)
Date: 09-10-2009
Publisher: Elsevier BV
Date: 1977
Publisher: Elsevier BV
Date: 02-1986
DOI: 10.1016/0006-291X(86)90389-X
Abstract: The kinetics of actin polymerization has been used to quantitate the relative levels of actin nucleating activity in extracts from a number of related tumorigenic and non-tumorigenic cells. The level of nucleating activity was significantly elevated in the tumorigenic compared with the non-tumorigenic cell extracts whether the results were expressed on the basis of per protein (2-3 fold increase) or per total endogenous cellular actin (3-4 fold increase). It is concluded that this activity is probably due to an actin filament capping/severing regulatory protein(s) and that this protein(s) may be, at least partially, responsible for the microfilament disruption observed in transformed cells.
Publisher: Elsevier BV
Date: 08-2014
DOI: 10.1016/J.BIOCEL.2014.04.025
Abstract: Molecular mechanisms that are associated with age-related denervation and loss of skeletal muscle mass and function (sarcopenia) are described for female C57Bl/6J mice aged 3, 15, 24, 27 and 29 months (m). Changes in mRNAs and proteins associated with myofibre denervation and protein metabolism in ageing muscles are reported, across the transition from healthy adult myofibres to sarcopenia that occurs between 15 and 24 m. This onset of sarcopenia at 24 m, corresponded with increased expression of genes associated with neuromuscular junction denervation including Chnrg, Chrnd, Ncam1, Runx1, Gadd45a and Myog. Sarcopenia in quadriceps muscles also coincided with increased protein levels for Igf1 receptor, Akt and ribosomal protein S6 (Rps6) with increased phosphorylation of Rps6 (Ser235/236) and elevated Murf1 mRNA and protein, but not Fbxo32: many of these changes are also linked to denervation. Global transcription profiling via microarray analysis confirmed these functional themes and highlighted additional themes that may be a consequence of pathology associated with sarcopenia, including changes in fatty acid metabolism, extracellular matrix structure and protein catabolism. Ageing was also associated with increased global gene expression variance, consistent with decreased control of gene regulation.
Publisher: Elsevier BV
Date: 07-2001
DOI: 10.1016/S0965-1748(01)00039-X
Abstract: The peritrophic matrix lines the midgut of most insects and has important roles in digestion, protection of the midgut from mechanical damage and invasion by micro-organisms. Although a few intrinsic peritrophic matrix proteins have been characterised, no direct homologues of any of these proteins have been found in other insect species, even closely related species, suggesting that the peritrophic matrix proteins show considerable sequence ergence. We now report the identification of the cDNA and genomic DNA sequences of a Chrysomya bezziana homologue of the Lucilia cuprina intrinsic peritrophic matrix protein, peritrophin-48. The gene for C. bezziana peritrophin-48 spans 1315 bp and consists of three exons (65, 560 and 690 bp, respectively) separated by introns of 566 and 72 bp. The transcriptional start site, identified by a consensus of cDNA clones and primer extension analysis, is probably located 58 bp upstream from the start codon. However, there may be multiple start sites for transcription. Two potential TATA boxes and a consensus arthropod transcription initiator are located within 134 bp of sequence upstream of the putative transcriptional start site suggesting that this region contains the gene promoter. Immuno-fluorescence localization demonstrated that C. bezziana peritrophin-48 was localised to the larval peritrophic matrix. Protein fold recognition analysis indicated structural similarities between peritrophin-48 and wheatgerm lectin. As wheatgerm lectin binds chitin, this result suggested that C. bezziana peritrophin-48 may also bind chitin, a constituent of the peritrophic matrix. Chitin binding studies with a recombinant peritrophin-48 protein confirmed that it binds chitin. A Drosophila melanogaster homologue of peritrophin-48 encoded in an EST and a genomic sequence was also identified. The pairwise percentage identities of the deduced amino acid sequences for the peritrophin-48 homologues from the three higher Dipteran species were relatively low, ranging between 32 and 42%. Despite this sequence variability, the predicted structure of these proteins, dictated by five domains, each containing a characteristic distribution of six cysteines, was strictly conserved. It is concluded that considerable sequence variation can be tolerated in this protein because of the constraints imposed on the structure of the protein by an extensive disulphide bonded framework.
Publisher: Springer Science and Business Media LLC
Date: 2009
Publisher: Springer Science and Business Media LLC
Date: 21-11-2009
DOI: 10.1007/S10719-009-9269-2
Abstract: Inhibition of bacterial adhesion to intestinal epithelial receptors by the consumption of natural food components is an attractive strategy for the prevention of microbial related gastrointestinal illness. We hypothesised that Muc1, a highly glycosylated mucin present in cows' milk, may be one such food component. Purified bovine Muc1 was tested for its ability to inhibit binding of common enteric bacterial pathogens to Caco-2 cells grown in vitro. Muc1 caused dose-dependent binding inhibition of Escherichia coli, Salmonella enterica serovar Typhimurium (S. Typhimurium), Staphylococcus aureus and Bacillus subtilis. This inhibition was more pronounced for the Gram negative compared with Gram positive bacteria. It was also demonstrated that Muc1, immobilised on a membrane, bound all these bacterial species in a dose-dependent manner, although there was greater interaction with the Gram negative bacteria. A range of monosaccharides, representative of the Muc1 oligosaccharide composition, were tested for their ability to prevent binding of E. coli and S. Typhimurium to Caco-2 cells. Inhibition was structure dependent with sialic acid, L(-) fucose and D(+) mannose significantly inhibiting binding of both Gram negative species. N-acetylglucosamine and N-acetylgalactosamine significantly inhibited binding of E. coli whilst galactose, one of the most abundant Muc1 monosaccharides, showed the strongest inhibition against S. Typhimurium. Treatment with sialidase significantly decreased the inhibitory properties of Muc1, demonstrating the importance of sialic acid in adhesion inhibition. It is concluded that bovine Muc1 prevents binding of bacteria to human intestinal cells and may have a role in preventing the binding of common enteropathogenic bacteria to human intestinal epithelial surfaces.
Publisher: MDPI AG
Date: 06-12-2017
DOI: 10.3390/IJMS18122628
Publisher: Elsevier BV
Date: 04-2008
Publisher: Wiley
Date: 02-07-2014
DOI: 10.1111/AGE.12132
Abstract: The callipyge phenotype in sheep involves substantial postnatal muscle hypertrophy and other changes to carcass composition. A single nucleotide polymorphism in the DLK1-DIO3 imprinted gene cluster alters gene expression of the paternal allele-specific protein-coding genes and several maternal allele-specific long noncoding RNA and microRNA when the mutation is inherited in cis. The inheritance pattern of the callipyge phenotype is polar overdominant because muscle hypertrophy only occurs in heterozygous animals that inherit a normal maternal allele and the callipyge SNP on the paternal allele (+/C). We examined the changes of gene expression of four major transcripts from the DLK1-DIO3 cluster and four myosin isoforms during the development of muscle hypertrophy in the semimembranosus as well as in the supraspinatus that does not undergo hypertrophy. The homozygous (C/C) animals had an intermediate gene expression pattern for the paternal allele-specific genes and two myosin isoforms, indicating a biological activity that was insufficient to change muscle mass. Transcriptome analysis was conducted by RNA sequencing in the four callipyge genotypes. The data show that homozygous animals (C/C) have lower levels of gene expression at many loci relative to the other three genotypes. A number of the downregulated genes are putative targets of the maternal allele-specific microRNA with gene ontology, indicating regulatory and cell signaling functions. These results suggest that the trans-effect of the maternal noncoding RNA and associated miRNA is to stabilize the expression of a number of regulatory genes at a functional, but low level to make the myofibers of homozygous (C/C) lambs less responsive to hypertrophic stimuli of the paternal allele-specific genes.
Publisher: Wiley
Date: 21-05-2001
DOI: 10.1002/ARCH.1038
Abstract: The midgut of most insects is lined with a peritrophic matrix, which is thought to facilitate digestion and protect the midgut digestive epithelial cells from abrasive damage and invasion by ingested micro-organisms. The type 2 peritrophic matrix is synthesised by a complex and highly specialised organ called the cardia typically located at the junction of the cuticle-lined foregut and midgut. Although the complex anatomy of this small organ has been described, virtually nothing is known of the molecular processes that lead to the assembly of the type 2 peritrophic matrix in the cardia. As a step towards understanding the synthesis of the peritrophic matrix, the synthesis and secretion of the intrinsic peritrophic matrix protein, peritrophin-15 has been followed in the cardia of Lucilia cuprina larvae using immuno-gold localisations. The protein is synthesised by cardia epithelial cells, which have abundant rough endoplasmic reticulum, Golgi, and vesicles indicative of a general secretory function. Peritrophin-15 is packaged into secretory vesicles probably produced from Golgi and transported to the cytoplasmic face of the apical plasma membrane. The vesicles fuse with the plasma membrane at the base of the microvilli and release peritrophin-15 into the inter-microvilli spaces. The protein then becomes associated with the nascent peritrophic matrix, which lies along the tips of the epithelial cell microvilli. It is proposed that peritrophin-15 binds to the ends of chitin fibrils present in the nascent peritrophic matrix, thereby protecting the fibril from the action of exochitinases.
Publisher: Elsevier BV
Date: 02-2003
DOI: 10.1016/S1096-4959(02)00265-8
Abstract: Dlk-1, a type 1 membrane glycoprotein, is a member of the Epidermal Growth Factor-like family of homeotic proteins that are typically involved in cell fate decisions and in mice it has been implicated in the control of differentiation of adipocytes. The aim of this study was to determine whether there were tissue-specific expression patterns of Dlk-1 splice variants in bovine tissues. Only the Dlk-1-C2 variant was expressed in adult bovine tissues while both Dlk-1-C2 and Dlk-1-A variants were expressed in foetal tissues. Quantitative real-time PCR revealed large differences in the relative levels of expression of the Dlk-1-C2 variant in adult adipose tissue depots with no expression in subcutaneous and brisket adipose tissues. Expression was also demonstrated in three adult skeletal muscle s les. The large variation in the level of expression of Dlk-1-C2 in different adult tissues may reflect the relative preadipocyte content of those tissues and consequently their potential for generating new adipocytes. A low abundance soluble glycoprotein (bFA1) was purified from bovine amniotic fluid. Analyses of its amino acid sequence revealed that it corresponded to most of the extracellular domain of bovine Dlk-1 and was derived by proteolytic processing from the full-length Dlk-1 protein encoded by the Dlk-1-A variant. The tissues expressing the Dlk-1-A variant have not been identified but are likely to be foetal in origin. Splice variants of Dlk-1 may have varied functional roles with the foetal Dlk-1-A form capable of generating a protein that undergoes proteolytic processing to release a soluble ecto-domain of Dlk-1. In contrast the Dlk-1-C2 splice variant codes for a protein lacking this processing site and therefore it probably remains bound to the cell membrane.
Publisher: Cold Spring Harbor Laboratory
Date: 28-04-2022
DOI: 10.1101/2022.04.26.488110
Abstract: Epistatic interactions can play an important role in the genetic mechanisms that control phenotypic variation. However, identifying these interactions in high dimensional genomic data can be very challenging due to the large computational burden induced by the high volume of combinatorial tests that have to be performed to explore the entire search space. Random Forests Decision Trees are widely used in a variety of disciplines and are often said to detect interactions. However, Random Forests models do not explicitly detect variable interactions. Most Random Forests based methods that claim to detect interactions rely on different forms of variable importance measures that suffer when the interacting variables have very small or no marginal effects. The proposed Random Forests based method detects interactions using a two-stage approach and is computationally efficient. The approach is demonstrated and validated through its application on several simulated datasets representing different data structures with respect to genomic data and trait heritabilities. The method is also applied to two high dimensional genomics data sets to validate the approach. In both cases, the method results were used to identify several genes closely positioned to the interacting markers that showed strong biological potential for contributing to the genetic control for the respective traits tested. hawlader.almamun@csiro.au
Publisher: Springer Science and Business Media LLC
Date: 2009
Publisher: Royal Society of Chemistry (RSC)
Date: 1986
DOI: 10.1039/DT9860001731
Publisher: Figshare
Date: 2011
Publisher: Elsevier BV
Date: 07-1996
DOI: 10.1016/0020-7519(96)00048-3
Abstract: Intensive lymphocytic infiltration of the underlying dermis occurs during cutaneous myiasis caused by larvae of the blow fly, Lucilia cuprina. To determine the effect of this infiltrate on larval growth, monoclonal antibodies (mAb) to CD4, CD8 or WC1 lymphocyte subset determinants were injected intravenously before and during experimental infection of sheep with larvae. The effect of intravenous injection of mAb to ovine interferon (IFN) gamma was also examined. The experiments were performed in 18-month-old maiden ewes with genetic resistance or susceptibility to the disease complex, bacterial dermatitis/cutaneous myiasis. mAbs induced profound depletion of CD8+ and WC1+ subpopulations from blood and skin at sites of larval growth. mAb to CD4+ gave only a moderate reduction in lymphocytes from blood or skin. mAb treatments did not modify larval growth or survival at 20 or 50 h after infection. Larval growth rates did not differ between resistant and susceptible genotypes. No evidence was found for a role of T lymphocyte subpopulations or the cytokine IFN, in modifying larval growth during the first 50 h of infection. It seems unlikely that T lymphocyte-dependent immunological effector mechanisms contribute to the lower prevalence of fly strike seen in the resistant genotype in the field.
Publisher: Elsevier BV
Date: 07-1991
DOI: 10.1016/0003-9861(91)90182-I
Abstract: Spectroscopically active terbium ions have been used to probe the Ca2+ ion-binding sites on human plasma gelsolin. The luminescence of Tb3+ ions bound to gelsolin is markedly enhanced when excited indirectly at 295 nm due to Förster type dipole-dipole energy transfer from neighboring tryptophan residues. Titration of this luminescence with increasing concentrations of Tb3+ ions was saturable although the shape of this titration curve was complex indicating the involvement of multiple classes of sites. Luminescence lifetime measurements (obtained by indirect excitation at 295 nm) demonstrate the presence of two classes of sites characterized by a major lifetime of 1.0-1.1 ms and a minor lifetime of 0.7-0.8 ms. However, while the litude of the minor lifetime showed a hyperbolic dependence on the Tb3+ ion concentration, the litude of the major lifetime showed a strongly sigmoidal dependence. Different classes of Tb3+ ion binding sites can also be distinguished by the different Ca2+ ion concentrations needed to displace Tb3+ ions from these sites on gelsolin. It is proposed that the occupancy of one class of Tb3+ ion binding sites on gelsolin causes a conformational change in gelsolin which then allows a second class of cryptic Tb3+ ion binding sites to be expressed. The implications of these results in terms of the binding of Ca2+ ions to gelsolin and the regulation of the activities of gelsolin by calcium are discussed.
Publisher: American Chemical Society (ACS)
Date: 23-09-1986
DOI: 10.1021/BI00367A068
Abstract: The effects of platelet gelsolin on the state and exchangeability of the nucleotide bound to skeletal muscle actin monomer have been investigated. In the presence of Ca2+, a stable ternary complex consisting of two actins and one gelsolin is formed. Removal of Ca2+ from this species results in the formation of a highly stable binary gelsolin-actin complex. The interaction of gelsolin with actin monomer has no effect on the virtually negligible [less than 0.01 mol of Pi X h-1 X (mol of actin)-1] intrinsic ATPase activity of actin monomer (in the absence of Mg2+). A single molecule of ATP is bound to the binary complex while two molecules of ATP are bound to the actins within the ternary complex. The ATP within the binary complex is nonexchangeable, and only one of the two ATP molecules in the ternary complex is exchangeable. In the latter case the rate constant for this nucleotide exchange is decreased compared to that for free actin monomer. These results demonstrate the nonequivalence of actin monomers within the ternary complex. The involvement of these oligomeric complexes of gelsolin and actin in the expression of the activity(ies) of gelsolin is discussed.
Publisher: Springer Science and Business Media LLC
Date: 10-01-2007
DOI: 10.1007/S10142-006-0042-3
Abstract: Rtl1 and Dlk1 are two genes in an imprinted gene cluster on mouse chromosome 12. Rtl1 is a paternally expressed gene encoding a retrotransposon-like protein, but as yet, there is no evidence that a protein is produced by this gene although a transcript is produced. Dlk1 is also paternally expressed and it encodes a plasma membrane-bound protein known to act as a negative regulator of adipogenesis. Genes at other imprinted loci often show coordinate expression and may interact at a functional level. We tested the hypothesis that Dlk1 and Rtl1 are functionally related. Rtl1 and Dlk1 mRNA expression patterns show similar time courses of down-regulation during induced adipogenesis of 3T3L1 cells. Despite the coordinate down-regulation of Dlk1 and Rtl1 mRNA levels, Rtl1 over-expression did not affect the time course of adipogenesis or Dlk1 expression. It is concluded that these two genes are neither directly nor indirectly functionally related.
Publisher: Elsevier BV
Date: 04-1996
Publisher: Cold Spring Harbor Laboratory
Date: 05-06-2017
DOI: 10.1101/143990
Abstract: Genome sequences for hundreds of mammalian species are available, but an understanding of their genomic regulatory regions, which control gene expression, is only beginning. A comprehensive prediction of potential active regulatory regions is necessary to functionally study the roles of the majority of genomic variants in evolution, domestication, and animal production. We developed a computational method to predict regulatory DNA sequences (promoters, enhancers and transcription factor binding sites) in production animals (cows and pigs) and extended its broad applicability to other mammals. The method utilizes human regulatory features identified from thousands of tissues, cell lines, and experimental assays to find homologous regions that are conserved in sequences and genome organization and are enriched for regulatory elements in the genome sequences of other mammalian species. Importantly, we developed a filtering strategy, including a machine learning classification method, to utilize a very small number of species-specific experimental datasets available to select for the likely active regulatory regions. The method finds the optimal combination of sensitivity and accuracy to unbiasedly predict regulatory regions in mammalian species. Furthermore, we demonstrated the utility of the predicted regulatory datasets in cattle for prioritizing variants associated with multiple production and climate change adaptation traits, and identifying potential genome editing targets.
Publisher: CSIRO Publishing
Date: 2005
DOI: 10.1071/EA05046
Abstract: Innate immunity plays a vital role in the protection of the bovine mammary gland against mastitis. Until recently, the migration of effector cells such as neutrophils and monocytes into the mammary gland was thought to provide the only defence against invading pathogens. However, mammary epithelial cells may also play an important role in the immune response, contributing to the innate defence of the mammary tissue through secretion of antimicrobial peptides and attraction of circulating immune effector cells. This paper reviews the innate immune pathways in mammary epithelial cells and examines their role in the initiation of an innate immune response to Gram-positive and Gram-negative bacteria.
Publisher: Proceedings of the National Academy of Sciences
Date: 19-08-1997
Abstract: Many insects feed on blood or tissue from mammalian hosts. One potential strategy for the control of these insects is to vaccinate the host with antigens derived from the insect. The larvae of the fly Lucilia cuprina feed on ovine tissue and tissue fluids causing a cutaneous myiasis associated with considerable host morbidity and mortality. A candidate vaccine antigen, peritrophin 95, was purified from the peritrophic membrane, which lines the gut of these larvae. Serum from sheep vaccinated with peritrophin 95 inhibited growth of first-instar L. cuprina larvae that fed on this serum. Growth inhibition was probably caused by antibody-mediated blockage of the normally semipermeable peritrophic membrane and the subsequent development of an impervious layer of undefined composition on the gut lumen side of the peritrophic membrane that restricted access of nutrients to the larvae. The amino acid sequence of peritrophin 95 was determined by cloning the DNA complementary to its mRNA. The deduced amino acid sequence codes for a secreted protein containing a distinct Cys-rich domain of 317 amino acids followed by a mucin-like domain of 139 amino acids. The Cys-rich domain may be involved in binding chitin. This report describes a novel immunological strategy for the potential control of L. cuprina larvae that may have general application to the control of other insect pests.
Publisher: CSIRO Publishing
Date: 2005
DOI: 10.1071/EA05049
Abstract: The callipyge mutation in sheep results in postnatal hypertrophy and leanness of skeletal muscles in the pelvic limbs and loins. Associated changes also occur in the expression of a number of imprinted genes flanking the site of the mutation, which lies at the telomeric end of ovine chromosome 18. The transcripts from several of these genes are either spliced or undergo substantial RNA processing, sometimes in a very complex manner. The current investigation examined the effects of the callipyge mutation on the relative expression of some of these splice variants in s les taken: at birth, when the muscle hypertrophy phenotype is not expressed and at 12 weeks of age, when the phenotype is fully apparent. It was concluded that changes in the postnatal developmental expression pattern of Dlk-1 are closely associated with the expression of the phenotype and that the callipyge mutation may promote a fetal-like gene expression program for some genes during postnatal life.
Publisher: Elsevier BV
Date: 04-1980
Publisher: American Chemical Society (ACS)
Date: 22-06-1982
DOI: 10.1021/BI00256A027
Location: United States of America
No related grants have been discovered for Ross Tellam.