ORCID Profile
0000-0002-8776-4710
Current Organisation
James Cook University
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Biochemistry and Cell Biology not elsewhere classified | Genetics not elsewhere classified | Genetics | Microbiology not elsewhere classified
Publisher: Wiley
Date: 10-04-2012
Publisher: The Company of Biologists
Date: 09-2006
DOI: 10.1242/JEB.02382
Abstract: This work, performed on the scleractinian coral Stylophora pistillata, aims at providing new information on the `light-enhanced calcification' process. In a first step, in controlled conditions of culture and constant light supply, we studied the diurnal cycle of calcification. We determined that calcification rates are constant during the day and the night with a 2.6-fold difference between day and night calcification rates. We also showed that the photosynthetic rate is constant throughout the day when a constant light intensity is applied. Our results on free-running experiments in prolonged conditions of light or dark suggest that calcification is not regulated by an endogenous circadian rhythm. In a second step, using a kinetic isotopic approach with 45Ca, we characterized the transition stages between day and night and vice versa. Under our experimental conditions, the lag-phase necessary to switch from the light to the dark calcification rate is the same as the lag-phase necessary to switch from the dark to the light calcification rate. We discuss our results in the context of two hypotheses of the light-enhanced calcification process: (1) the role of photosynthesis on the pH in the coelenteron and (2) the role of photosynthesis in supplying precursors of the organic matrix.
Publisher: Springer Science and Business Media LLC
Date: 16-01-2016
Publisher: Wiley
Date: 18-06-2016
DOI: 10.1111/GCB.13350
Abstract: Shelled pteropods play key roles in the global carbon cycle and food webs of various ecosystems. Their thin external shell is sensitive to small changes in pH, and shell dissolution has already been observed in areas where aragonite saturation state is ~1. A decline in pteropod abundance has the potential to disrupt trophic networks and directly impact commercial fisheries. Therefore, it is crucial to understand how pteropods will be affected by global environmental change, particularly ocean acidification. In this study, physiological and molecular approaches were used to investigate the response of the Mediterranean pteropod, Heliconoides inflatus, to pH values projected for 2100 under a moderate emissions trajectory (RCP6.0). Pteropods were subjected to pH
Publisher: Public Library of Science (PLoS)
Date: 09-01-2012
Publisher: Elsevier BV
Date: 03-2013
DOI: 10.1016/J.BMC.2012.10.024
Abstract: Coral reefs are among the most biologically erse and economically important ecosystems on the planet. The deposition of massive calcium carbonate skeletons (biomineralization or calcification) by scleractinian corals forms the coral reef framework/architecture that serves as habitat for a large ersity of organisms. This process would not be possible without the intimate symbiosis between corals and photosynthetic dinoflagellates, commonly called zooxanthellae. Carbonic anhydrases play major roles in those two essential processes of coral's physiology: they are involved in the carbon supply for calcium carbonate precipitation as well as in carbon-concentrating mechanisms for symbiont photosynthesis. Here, we review the current understanding of ersity and function of carbonic anhydrases in corals and discuss the perspective of theses enzymes as a key to understanding impacts of environmental changes on coral reefs.
Publisher: Elsevier BV
Date: 09-2008
DOI: 10.1016/J.CBPA.2008.05.009
Abstract: High calcification rates observed in reef coral organisms are due to the symbiotic relationship established between scleractinian corals and their photosynthetic dinoflagellates, commonly called zooxanthellae. Zooxanthellae are known to enhance calcification in the light, a process referred as "light-enhanced calcification". The disruption of the relationship between corals and their zooxanthellae leads to bleaching. Bleaching is one of the major causes of the present decline of coral reefs related to climate change and anthropogenic activities. In our aquaria, corals experienced a chemical pollution leading to bleaching and ending with the death of corals. During the time course of this bleaching event, we measured multiple parameters and could evidence four major consecutive steps: 1) at month 1 (January 2005), the stress affected primarily the photosystem II machinery of zooxanthellae resulting in an immediate decrease of photosystem II efficiency, 2) at month 2, the stress affected the photosynthetic production of O2 by zooxanthellae and the rate of light calcification, 3) at month 3, there was a decrease in both light and dark calcification rates, the appearance of the first oxidative damage in the zooxanthellae, the disruption of symbiosis, 4) and finally the death of corals at month 6.
Publisher: Elsevier BV
Date: 06-2021
DOI: 10.1016/J.CUB.2021.03.028
Abstract: Coral reefs are the epitome of species ersity, yet the number of described scleractinian coral species, the framework-builders of coral reefs, remains moderate by comparison. DNA sequencing studies are rapidly challenging this notion by exposing a wealth of undescribed ersity, but the evolutionary and ecological significance of this ersity remains largely unclear. Here, we present an annotated genome for one of the most ubiquitous corals in the Indo-Pacific (Pachyseris speciosa) and uncover, through a comprehensive genomic and phenotypic assessment, that it comprises morphologically indistinguishable but ecologically ergent lineages. Demographic modeling based on whole-genome resequencing indicated that morphological crypsis (across micro- and macromorphological traits) was due to ancient morphological stasis rather than recent ergence. Although the lineages occur sympatrically across shallow and mesophotic habitats, extensive genotyping using a rapid molecular assay revealed differentiation of their ecological distributions. Leveraging "common garden" conditions facilitated by the overlapping distributions, we assessed physiological and quantitative skeletal traits and demonstrated concurrent phenotypic differentiation. Lastly, spawning observations of genotyped colonies highlighted the potential role of temporal reproductive isolation in the limited admixture, with consistent genomic signatures in genes related to morphogenesis and reproduction. Overall, our findings demonstrate the presence of ecologically and phenotypically ergent coral species without substantial morphological differentiation and provide new leads into the potential mechanisms facilitating such ergence. More broadly, they indicate that our current taxonomic framework for reef-building corals may be scratching the surface of the ecologically relevant ersity on coral reefs, consequently limiting our ability to protect or restore this ersity effectively.
Publisher: Springer Science and Business Media LLC
Date: 30-09-2006
Publisher: Wiley
Date: 2015
DOI: 10.1111/MEC.13021
Abstract: Corals play a key role in ocean ecosystems and carbonate balance, but their molecular response to ocean acidification remains unclear. The only previous whole-transcriptome study (Moya et al. Molecular Ecology, 2012 21, 2440) documented extensive disruption of gene expression, particularly of genes encoding skeletal organic matrix proteins, in juvenile corals (Acropora millepora) after short-term (3 d) exposure to elevated pCO2 . In this study, whole-transcriptome analysis was used to compare the effects of such 'acute' (3 d) exposure to elevated pCO2 with a longer ('prolonged' 9 d) period of exposure beginning immediately post-fertilization. Far fewer genes were differentially expressed under the 9-d treatment, and although the transcriptome data implied wholesale disruption of metabolism and calcification genes in the acute treatment experiment, expression of most genes was at control levels after prolonged treatment. There was little overlap between the genes responding to the acute and prolonged treatments, but heat shock proteins (HSPs) and heat shock factors (HSFs) were over-represented amongst the genes responding to both treatments. Amongst these was an HSP70 gene previously shown to be involved in acclimation to thermal stress in a field population of another acroporid coral. The most obvious feature of the molecular response in the 9-d treatment experiment was the upregulation of five distinct Bcl-2 family members, the majority predicted to be anti-apoptotic. This suggests that an important component of the longer term response to elevated CO2 is suppression of apoptosis. It therefore appears that juvenile A. millepora have the capacity to rapidly acclimate to elevated pCO2 , a process mediated by upregulation of specific HSPs and a suite of Bcl-2 family members.
Publisher: Inter-Research Science Center
Date: 12-07-2013
DOI: 10.3354/MEPS10318
Publisher: Springer Science and Business Media LLC
Date: 16-09-2008
DOI: 10.1007/S10126-008-9141-6
Abstract: Bone morphogenetic proteins (BMPs) are members of the transforming growth factor beta superfamily, and have been identified by their ability to induce bone formation in vertebrates. The biomineral-forming process, called biomineralization, is a widespread process, present in all kingdoms of living organisms and among which stony corals are one of the major groups of calcifying animals. Here, we report the presence of a BMP2/4 ortholog in eight species of adult corals. The synthesis of such a protein by the calcifying epithelium of corals suggests that coral BMP2/4 plays a role in skeletogenesis, making BMP the first common protein involved in biomineralization among Eumetazoans. In addition we show that recombinant coral BMP2/4 is able to inhibit human BMP2-induced osteoblastic differentiation in mesenchymal C2C12 cells. We suggest that this inhibition results from a competition between coral BMP2/4 and human BMP2, indicating conservation of binding affinity of BMP and its receptor during evolution from corals to vertebrates. Further studies are needed to understand interactions between coral BMP2/4 and its receptors, and, thus, the action of BMP2/4 in adult corals.
Publisher: Springer Science and Business Media LLC
Date: 19-04-2008
DOI: 10.1007/S10126-008-9101-1
Abstract: This paper aims to validate reference genes for gene expression studies between light and dark conditions in the scleractinian coral Stylophora pistillata for future gene expression studies of the "light-enhanced calcification" phenomenon. For this purpose, we cloned, sequenced, and characterized a candidate reference gene, the 36B4 gene from the coral S. pistillata, and validated 36B4 and beta-actin as reference genes. To illustrate the future applications of these reference genes, we tested the dark and light expression of two photosynthetic genes (Rubisco and D1 protein of the photosystem II) and two genes encoding proteins involved in calcium transport for coral calcification (a calcium ATPase and a calcium channel). Results show that both photosynthetic genes are enhanced during the light when standardized against 36B4 and beta-actin, whereas the two genes encoding proteins involved in calcium transport are not differentially expressed between light and dark conditions. The characterization of a coral 36B4 and the establishment of such valid reference genes will be useful for future gene expression studies between erse conditions (aposymbiotic/symbiotic, stress/control, light/dark conditions) in scleractinian corals.
Publisher: Elsevier BV
Date: 12-2015
DOI: 10.1016/J.MARGEN.2015.08.001
Abstract: Declining health of scleractinian corals in response to deteriorating environmental conditions is widely acknowledged, however links between physiological and functional genomic responses of corals are less well understood. Here we explore growth and the expression of 20 target genes with putative roles in metabolism and calcification in the branching coral, Acropora millepora, in two separate experiments: 1) elevated pCO2 (464, 822, 1187 and 1638 μatm) and ambient temperature (27°C), and 2) elevated pCO2 (490 and 822 μatm) and temperature (28 and 31 °C). After 14 days of exposure to elevated pCO2 and ambient temperatures, no evidence of differential expression of either calcification or metabolism genes was detected between control and elevated pCO2 treatments. After 37 days of exposure to control and elevated pCO2, Ubiquinol-Cytochrome-C Reductase Subunit 2 gene (QCR2 a gene involved in complex III of the electron chain transport within the mitochondria and critical for generation of ATP) was significantly down-regulated in the elevated pCO2 treatment in both ambient and elevated temperature treatments. Overall, the general absence of a strong response to elevated pCO2 and temperature by the other 19 targeted calcification and metabolism genes suggests that corals may not be affected by these stressors on longer time scales (37 days). These results also highlight the potential for QCR2 to act as a biomarker of coral genomic responses to changing environments.
Publisher: Public Library of Science (PLoS)
Date: 21-07-2011
Publisher: Cold Spring Harbor Laboratory
Date: 05-09-2020
DOI: 10.1101/2020.09.04.260208
Abstract: Coral reefs are the epitome of species ersity, yet the number of described scleractinian coral species, the framework-builders of coral reefs, remains moderate by comparison. DNA sequencing studies are rapidly challenging this notion by exposing a wealth of undescribed ersity, but the evolutionary and ecological significance of this ersity remains largely unclear. Here, we present an annotated genome for one of the most ubiquitous corals in the Indo-Pacific ( Pachyseris speciosa ), and uncover through a comprehensive genomic and phenotypic assessment that it comprises morphologically indistinguishable, but ecologically ergent cryptic lineages. Demographic modelling based on whole-genome resequencing disproved that morphological crypsis was due to recent ergence, and instead indicated ancient morphological stasis. Although the lineages occur sympatrically across shallow and mesophotic habitats, extensive genotyping using a rapid diagnostic assay revealed differentiation of their ecological distributions. Leveraging “common garden” conditions facilitated by the overlapping distributions, we assessed physiological and quantitative skeletal traits and demonstrated concurrent phenotypic differentiation. Lastly, spawning observations of genotyped colonies highlighted the potential role of temporal reproductive isolation in the limited admixture, with consistent genomic signatures in genes related to morphogenesis and reproduction. Overall, our findings demonstrate how ecologically and phenotypically ergent coral species can evolve despite morphological stasis, and provide new leads into the potential mechanisms facilitating such ergence in sympatry. More broadly, they indicate that our current taxonomic framework for reef-building corals may be scratching the surface of the ecologically relevant ersity on coral reefs, consequently limiting our ability to protect or restore this ersity effectively.
Publisher: Wiley
Date: 21-09-2020
DOI: 10.1111/MEC.15612
Publisher: Elsevier BV
Date: 07-2013
DOI: 10.1016/J.JSB.2013.05.005
Abstract: One of the most important aspects in the research on reef-building corals is the process by which corals accrete biogenic calcium carbonate. This process leads to the formation of a mineral/organic composite and it is believed that the development of the nano- and microstructure of the mineral phase is highly sensitive to the growth conditions. Transmission electron microscopy (TEM) analysis of large-scale (10×30μm) focused ion beam (FIB) prepared lamellae was performed on adult and juvenile scleractinian coral skeleton specimens. This allowed for the investigation of the nano and microstructure and the crystallographic orientation of the aragonite mineral. We found the following microstructural evolution in the adult Porites lobata specimens: randomly oriented nanocrystals with high porosity, partly aligned nanocrystals with high porosity and areas of dense acicular crystals of several micrometers extension, the latter two areas are aligned close to the [001] direction (Pmcn space group). To the best of our knowledge, for the first time the observed microstructure could be directly correlated with the dark/bright bands characteristic of the diurnal growth cycle. We hypothesize that this mineral structure sequence and alignment in the adult specimen is linked to the photosynthetic diurnal cycle of the zooxanthellea regulating the oxygen levels and organic molecule transport to the calcifying medium. These observations reveal a strong control of crystal morphology by the organism and the correlation of the accretion process. No indication for a self-assembly of nanocrystalline units, i.e., a mesocrystal structure, on the micrometer scale could be found.
Publisher: Elsevier BV
Date: 09-2008
Publisher: Inter-Research Science Center
Date: 14-02-2013
DOI: 10.3354/MEPS10077
Publisher: Springer Science and Business Media LLC
Date: 05-07-2016
Publisher: Wiley
Date: 31-01-2012
Start Date: 02-2017
End Date: 06-2021
Amount: $290,608.00
Funder: Australian Research Council
View Funded Activity