Regulation Of Synthesis, Dimerisation And Secretion Of The Amyloidogenic Protease Inhibitor Cystatin C
Funder
National Health and Medical Research Council
Funding Amount
$423,565.00
Summary
The cells that compose our tissues are embedded in a complex mesh of extracellular proteins (for example collagen) that provide support, strenght and elasticity to the tissues. This extracellular matrix is not static; it is constantly remodelled when, for example, the cells of the immune system move through interstitial spaces to monitor the healthiness of the tissues. When infections or injuries occur, the inflammatory reactions that develop, and the processes involved in tissue repair, also in ....The cells that compose our tissues are embedded in a complex mesh of extracellular proteins (for example collagen) that provide support, strenght and elasticity to the tissues. This extracellular matrix is not static; it is constantly remodelled when, for example, the cells of the immune system move through interstitial spaces to monitor the healthiness of the tissues. When infections or injuries occur, the inflammatory reactions that develop, and the processes involved in tissue repair, also involve profound changes in the composition of the extracellular matrix. Such processes are also important for tumour growth; the cancer cells need to clear their way through interstitial space to escape to circulation and metastasize. During all these processes, the cells release to the extracellular space proteases that degrade collagen and the other components of the extracellular matrix. Obviously, these proteases must be tightly regulated to prevent them running out of control, so the cells also produce inhibitors of the proteases. The amount of proteases and inhibitors contained in the extracellular space must be maintained properly. If this equilibrium is disrupted, this can lead to pathology For instance, atherosclerosis is caused in part by excessive proteolysis of the blood vessel wall. In this project we want to study the mechanisms of one of the most abundant and important inhibitors of extracellular proteolysis: Cystatin C. We have discovered that certain cells of the immune system called dendritic cells posses interesting mechanisms to regulate how much Cystatin C they secrete. Furthermore, one of this mechanisms, which consists of pairing the protein to produce inactive dimers, may be the cause of some diseases characterised by accumulation of Cystatin C in the extracellular space. Our study may allow us to design therapies for the treatment of pathologies associated with defective or excessive production of Cystatin C.Read moreRead less
Synthesis of substrate analogues for probing catalytic mechanisms and specificity of enzymes involved in the metabolism of plant polysaccharides. The project is aimed at strengthening collaborations between research groups in Adelaide and France, with the specific objective of synthesizing substrate analogues as probes of enzymatic mechanisms and substrate specificity in polysaccharide hydrolases and synthases of barley. The chemical expertise resides in France, while the enzymatic work will be ....Synthesis of substrate analogues for probing catalytic mechanisms and specificity of enzymes involved in the metabolism of plant polysaccharides. The project is aimed at strengthening collaborations between research groups in Adelaide and France, with the specific objective of synthesizing substrate analogues as probes of enzymatic mechanisms and substrate specificity in polysaccharide hydrolases and synthases of barley. The chemical expertise resides in France, while the enzymatic work will be conducted largely in Australia. Exchange of research staff, particularly at the postgraduate student and research associate levels, is considered essential to capture the benefits of the complementary expertise and to extend an existing international collaboration. The target enzymes are of central importance in cell wall metabolism during development of higher plants.Read moreRead less
Molecular mechanisms of catalysis and the basis of substrate specificity in polysaccharide hydrolases. Reaction intermediates along hydrolytic pathways and molecular determinants of substrate specificity of barley B-glucan exo- and endohydrolases will be defined using crystallographic and kinetic analyses. These enzymes are of central importance in cell wall metabolism during development of higher plants, and in plant-pathogen interactions. Realization of the project objectives will not only pro ....Molecular mechanisms of catalysis and the basis of substrate specificity in polysaccharide hydrolases. Reaction intermediates along hydrolytic pathways and molecular determinants of substrate specificity of barley B-glucan exo- and endohydrolases will be defined using crystallographic and kinetic analyses. These enzymes are of central importance in cell wall metabolism during development of higher plants, and in plant-pathogen interactions. Realization of the project objectives will not only provide fundamental information on catalytic mechanisms, but will also provide opportunities to manipulate enzyme specificity. Further, site-directed mutagenesis of the enzymes will be used to generate glycosynthases, which will be evaluated for their ability to synthesise novel oligosaccharide and polysaccharide products, some of which might show immunomodulating activity.Read moreRead less
The regulation of signalling molecules in Saccharomyces Cerevisiae by inositol polyphosphate 5-phosphatases. Phosphoinositide signalling molecules regulate the actin cytoskeleton, secretion, vesicular trafficking and cell growth and death. We have identified, cloned and characterised a family of signal terminating enzymes called inositol polyphosphate 5-phosphatases (5-phosphatases) that regulate phosphoinositide signalling molecules. We have cloned and characterised four distinct 5-phosphatases ....The regulation of signalling molecules in Saccharomyces Cerevisiae by inositol polyphosphate 5-phosphatases. Phosphoinositide signalling molecules regulate the actin cytoskeleton, secretion, vesicular trafficking and cell growth and death. We have identified, cloned and characterised a family of signal terminating enzymes called inositol polyphosphate 5-phosphatases (5-phosphatases) that regulate phosphoinositide signalling molecules. We have cloned and characterised four distinct 5-phosphatases in the yeast Saccharomyces Cerevisiae and demonstrated by both deletion and overexpression studies that these enzymes regulate the actin cytoskeleton, endocytosis and secretion. This research proposal aims to investigate the signalling complexes the 5-phosphatases form with specific actin binding and or regulatory proteins, investigate the complex interactions of phosphoinositide lipid phosphatases and the roles they play in regulating secretion from the endoplasmic reticulum and finally characterize a novel 5-phosphatase that we have recently identified. Collectively the outcome of these studies will provide novel information about the functionallly significant signalling pathways regulated by this important enzyme family.Read moreRead less
The role of PtdIns(4,5)P2 in cellular responses in Saccharomyces cerevisiae. This grant application falls under the criteria of frontier technologies in genomics/phenomics and complex systems. We are characterizing a highly conserved network of signaling molecules regulated by complex large families of enzymes that regulate the bending of membranes, and cellular events including cell division in plants, yeast and mammalian cells. We have developed cutting edge novel technologies to localize sign ....The role of PtdIns(4,5)P2 in cellular responses in Saccharomyces cerevisiae. This grant application falls under the criteria of frontier technologies in genomics/phenomics and complex systems. We are characterizing a highly conserved network of signaling molecules regulated by complex large families of enzymes that regulate the bending of membranes, and cellular events including cell division in plants, yeast and mammalian cells. We have developed cutting edge novel technologies to localize signaling on specific intracellular membranes and visualise the role cellular lipids play in forming tubules in cells. This project will result in the presentation of Australian research at international forums and support the training of PhD students.Read moreRead less
Polysaccharide Synthase Genes in Agro-Industrial Applications. Achievement of the project aims will generate valuable intellectual property and meet National Research Priorities by: enhancing our knowledge base for the production of renewable bio-fuels from crop residues, for an environmentally sustainable Australia; developing preventative healthcare through adoption of healthier diets, rich in non-starchy cell wall polysaccharides that help reduce the incidence and severity of cardiovascular d ....Polysaccharide Synthase Genes in Agro-Industrial Applications. Achievement of the project aims will generate valuable intellectual property and meet National Research Priorities by: enhancing our knowledge base for the production of renewable bio-fuels from crop residues, for an environmentally sustainable Australia; developing preventative healthcare through adoption of healthier diets, rich in non-starchy cell wall polysaccharides that help reduce the incidence and severity of cardiovascular disease, obesity, diabetes and some cancers; and by developing breakthrough science in emerging agricultural technologies. The alliance will foster an intellectual environment to provide world-class basic research outcomes and training of highly skilled graduates, thereby contributing to the 'knowledge nation'.Read moreRead less
Linkage Infrastructure, Equipment And Facilities - Grant ID: LE0214135
Funder
Australian Research Council
Funding Amount
$492,000.00
Summary
High performance protein crystallography. This proposal will provide state of the art high performance facilities for protein crystallography, bringing together the major structural biology groups in NSW and the ACT. A renewed focus on protein crystal structures will stimulate new interpretation and utilization of the vast amount of data that has come from genomics, especially the sequencing of the human genome. The proposed facility will generate new research collaborations between the partn ....High performance protein crystallography. This proposal will provide state of the art high performance facilities for protein crystallography, bringing together the major structural biology groups in NSW and the ACT. A renewed focus on protein crystal structures will stimulate new interpretation and utilization of the vast amount of data that has come from genomics, especially the sequencing of the human genome. The proposed facility will generate new research collaborations between the partner institutions which will result in advances in basic life sciences, biotechnology and biopharmaceuticals. The facility will complement regional initiatives in functional genomics, bioinformatics, proteomics and high-field NMR spectroscopy.Read moreRead less
Structures and Functions of Bacterial Replisomal Proteins. DNA replication in all organisms requires many proteins to interact in a structure called the replisome. The bacterial replisome is assembled about the DnaB helicase, a motor protein that moves along DNA, separating the strands of duplex regions in its path. This project aims to develop understanding of the chemistry of DnaB and other replisomal proteins: their structures, how they work, and how they interact to assemble the replisome. T ....Structures and Functions of Bacterial Replisomal Proteins. DNA replication in all organisms requires many proteins to interact in a structure called the replisome. The bacterial replisome is assembled about the DnaB helicase, a motor protein that moves along DNA, separating the strands of duplex regions in its path. This project aims to develop understanding of the chemistry of DnaB and other replisomal proteins: their structures, how they work, and how they interact to assemble the replisome. This has the potential to lead to design of new antibacterial drugs.
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Angiogenic defects in mutant growth plate cartilage reveal new modulators of vascular invasion. Converting cartilage to bone requires blood vessel invasion from the bony interface. This project will test, in vitro and in vivo, the hypothesis that collagen fragments regulate blood vessel invasion into cartilage. This data will have implications for processes requiring new blood vessels such as bone growth, cancer, inflammation and ischemia.
Structural basis of the neuroendocrine enzyme GAD65-mediated autoimmunity in Type 1 Diabetes. More than 80 per cent of patients with Type 1 Diabetes develop antibodies against the neuroendocrine enzyme GAD65. This project will use state-of-the art techniques to study the interaction of GAD65 with antibodies in molecular detail. This will provide key insights into the molecular mechanisms of autoimmune disease.