Project description:Non-targeted LC-MS/MS of PPL extracts from experimental and environmental seawater samples from coral reefs from Mo'orea (French Polynesia), collected in May 2019.
Project description:Transcriptional profiling of gene responses in liver in the coral reef fish Pomacentrus moluccensis in response to different types of environmental stress: cold, heat, hypoxic and hyposmotic shock. Goal was to determine the common effects of different types of environmental stress on gene expression as well as responses unique to different stressors. Abstract from Kassahn et al. BMC Genomics (2007) 8:358 Background While our understanding of the importance of transcriptional regulation for biological function is continuously growing, we still know comparatively little about how environmentally-induced stress affects gene expression in vertebrates and how consistent transcriptional stress responses are across different types of environmental stress. Results In this study, we looked for a genetic measure of environmental stress and used a multi-stressor approach to identify components of a common stress response as well as components unique to different types of environmental stress. We exposed individuals of the coral reef fish Pomacentrus moluccensis to hypoxic, hyposmotic, cold and heat shock and measured the responses of approximately 16,000 genes in liver. We also compared winter and summer responses to heat shock to examine the capacity for such responses to vary with acclimation to different ambient temperatures. We identified a series of gene functions that were consistently involved in all stress responses examined here, suggesting common effects of stress on biological function. These common responses were achieved by the regulation of largely independent sets of genes and the responses of individual genes varied greatly across different stress types. However, we were able to identify groups of co-regulated genes, the genes within which shared similar functions. Given current estimates of climatic change, we were particularly interested in the response to prolonged heat exposure. In total, 324 gene loci were differentially expressed following exposure to heat over five days. The functions of these heat-responsive genes suggest that prolonged heat stress leads to oxidative stress and protein damage, challenge of the immune system, and a re-allocation of energy sources. Conclusion This is the first environmental genomic study to measure gene regulation in response to different environmental stressors in a natural population of a warm-adapted ectothermic vertebrate. This study offers insight into the effects of environmental stress on biological function and sheds light on the expected sensitivity of coral reef fishes to elevated temperatures in the future. Keywords: Stress response
Project description:Non-targeted LC-MS/MS of PPL extracts from experimental and environmental seawater samples from coral reefs from Mo'orea (French Polynesia), collected in May 2019.
Project description:The Moorea Coral Reef Long Term Ecological Research (LTER) Site (17.50°S, 149.83°W) comprises the fringe of coral reefs and lagoons surrounding the volcanic island of Moorea in the Society Islands of French Polynesia. As part of our Microbial Inventory Research Across Diverse Aquatic LTERS biodiversity inventory project, we characterized microbial community composition across all three domains of life using amplicon pyrosequencing of the V6 (bacterial and archaeal) and V9 (eukaryotic) hypervariable regions of small-subunit ribosomal RNA genes. Our survey spanned eight locations along a 130-km transect from the reef lagoon to the open ocean to examine changes in communities along inshore to offshore gradients. Our results illustrate consistent community differentiation between inshore and offshore ecosystems across all three domains, with greater richness in all domains in the reef-associated habitats. Bacterial communities were more homogenous among open ocean sites spanning >100 km than among inshore sites separated by <1 km, whereas eukaryotic communities varied more offshore than inshore, and archaea showed more equal levels of dissimilarity among subhabitats. We identified signature communities representative of specific geographic and geochemical milieu, and characterized co-occurrence patterns of specific microbial taxa within the inshore ecosystem including several bacterial groups that persist in geographical niches across time. Bacterial and archaeal communities were dominated by few abundant taxa but spatial patterning was consistent through time and space in both rare and abundant communities. This is the first in-depth inventory analysis of biogeographic variation of all three microbial domains within a coral reef ecosystem.