Project description:We sequenced and assembled de novo the coding transcriptomes in four species of Notothenioid fish: Neopagetopsis ionah (Jonah’s ice fish), Pseudochaenichtys georgianus (South Georgia icefish), Harpagifer antarcticus (Antarctic spiny plunderfish) and Parachaenichthys charcoti (Charcot’s dragonfish). We sampled 1-4 individuals and 1-14 tissues (brain, white muscle, liver, head kidney, trunk kidney, skin, heart, red muscle, spleen, ovary, testis, whole blood, gill, red blood cells) in each species, depending on tissue availability.
Project description:The goal of this study was to measure the effect of heat stress on the transcriptome of a cold-adapted fish species - Trematomus bernacchii - an Antarctic fish species. Keywords: Stress response
Project description:Because of severe abiotic limitations, Antarctic soils represent simplified ecosystems, where microorganisms are the principle drivers of nutrient cycling. This relative simplicity makes these ecosystems particularly vulnerable to perturbations, like global warming, and the Antarctic Peninsula is among the most rapidly warming regions on the planet. However, the consequences of the ongoing warming of Antarctica on microorganisms and the processes they mediate are unknown. Here, using 16S rRNA gene pyrosequencing and qPCR, we report a number of highly consistent changes in microbial community structure and abundance across very disparate sub-Antarctic and Antarctic environments following three years of experimental field warming (+ 0.5-2°C). Specifically, we found significant increases in the abundance of fungi and bacteria and in the Alphaproteobacteria-to-Acidobacteria ratio. These alterations were linked to a significant increase in soil respiration. Furthermore, the shifts toward generalist or opportunistic bacterial communities following warming weakened the linkage between bacterial diversity and functional diversity. Warming also increased the abundance of some organisms related to the N-cycle, detected as an increase in the relative abundance of nitrogenase genes via GeoChip microarray analyses. Our results demonstrate that soil microorganisms across a range of sub-Antarctic and Antarctic environments can respond consistently and rapidly to increasing temperatures, thereby potentially disrupting soil functioning.
2010-12-30 | GSE22825 | GEO
Project description:Evolution of host defence in notothenioid fishes in the Antarctic Ocean
Project description:The Antarctic eelpout, Pachycara brachycephalum, is a member of the cosmopolitan fish family Zoarcidae, which comprises 284 species distributed all over the globe. Since the Antarctic realm is a highly constant habitat, the species P. brachycephalum was employed in a global approach to characterize thermal response mechanisms in terms of long-term cold- and warm acclimation. Specimen of P. brachycephalum were incubated for 2 months at six different temperatures: -1C, 0C (control), 3C, 5C, 7C, 9C. In each group 5 fish were selected for hybridization (except control: n=7). By comparing the features of control and treatment groups we addressed temperature dependent expression profiles in liver tissue.
