Project description:The fate of the carbon stocked in permafrost soils following global warming and permafrost thaw is of major concern in view of the potential for increased CH4 and CO2 emissions from these soils. Complex carbon compound degradation and greenhouse gas emissions are due to soil microbial communities, but their composition and functional potential in permafrost soils are largely unknown. Here, a 2 m deep permafrost and its overlying active layer soil were subjected to metagenome sequencing, quantitative PCR, and microarray analyses. The active layer soil and 2 m permafrost soil microbial community structures were very similar, with Actinobacteria being the dominant phylum. The two soils also possessed a highly similar spectrum of functional genes, especially when compared to other already published metagenomes. Key genes related to methane generation, methane oxidation and organic matter degradation were highly diverse for both soils in the metagenomic libraries and some (e.g. pmoA) showed relatively high abundance in qPCR assays. Genes related to nitrogen fixation and ammonia oxidation, which could have important roles following climatic change in these nitrogen-limited environments, showed low diversity but high abundance. The 2 m permafrost soil showed lower abundance and diversity for all the assessed genes and taxa. Experimental biases were also evaluated and showed that the whole community genome amplification technique used caused large representational biases in the metagenomic libraries. This study described for the first time the detailed functional potential of permafrost-affected soils and detected several genes and microorganisms that could have crucial importance following permafrost thaw.
Project description:The fate of the carbon stocked in permafrost soils following global warming and permafrost thaw is of major concern in view of the potential for increased CH4 and CO2 emissions from these soils. Complex carbon compound degradation and greenhouse gas emissions are due to soil microbial communities, but their composition and functional potential in permafrost soils are largely unknown. Here, a 2 m deep permafrost and its overlying active layer soil were subjected to metagenome sequencing, quantitative PCR, and microarray analyses. The active layer soil and 2 m permafrost soil microbial community structures were very similar, with Actinobacteria being the dominant phylum. The two soils also possessed a highly similar spectrum of functional genes, especially when compared to other already published metagenomes. Key genes related to methane generation, methane oxidation and organic matter degradation were highly diverse for both soils in the metagenomic libraries and some (e.g. pmoA) showed relatively high abundance in qPCR assays. Genes related to nitrogen fixation and ammonia oxidation, which could have important roles following climatic change in these nitrogen-limited environments, showed low diversity but high abundance. The 2 m permafrost soil showed lower abundance and diversity for all the assessed genes and taxa. Experimental biases were also evaluated and showed that the whole community genome amplification technique used caused large representational biases in the metagenomic libraries. This study described for the first time the detailed functional potential of permafrost-affected soils and detected several genes and microorganisms that could have crucial importance following permafrost thaw. A 2m deep permafrost sample and it overlying active layer were sampled and their metagenome analysed. For microarray analyses, 8 other soil samples from the same region were used for comparison purposes.
Project description:Understanding molecular mechanism associated with high altitude exposure during acclimatization/adaptation/maladaptation. Data reveals specific components of the complex molecular circuitry underlying high altitude pulmonary edema. Individualized outcome prediction were constructed through expression profiling of 39400 genes in sea level sojourners who were acclimatized to high altitude and grouped as controls (n=14), high altitude natives (n=14) and individuals who developed high altitude pulmonary edema within 48-72 hours after air induction to high altitude (n=17).
Project description:Purpose: High-altitude adaptive evolution of transcription, and the convergence and divergence of transcriptional alteration across species in response to high-altitude environments, is an important topic of broad interest to the general biology community. Our study aims to answer this important biological question. Methods: We generated deep transcriptome data of high- and low- altitude populations across four species: chicken, pig, goat and sheep, as well as high-altitude yak and low-altitude cattle, from six tissues (heart, kidney, liver, lung, skeletal muscle and spleen). Results: Here we provide a comprehensive comparative transcriptome landscape of expression and alternative splicing variation between low- and high-altitude populations across multiple species for distinct tissues. Conclusions: Our data serves a valuable resource for further study on adaptive transcription evolution and identification of candidate adaptive genes.
Project description:Altitude acclimatization is the physiological process to restore oxygen delivery to the tissues and promote the oxygen application under high altitude hypoxia. High altitude illness could happen in individuals who did not get acclimatization. Unraveling the molecular underpinnings of altitude acclimatization would help people to understand the beneficial response of body to high altitude hypoxia and disturbed biological process in un-acclimatized individuals. Here, we measured physiological adjustments and circulating microRNAs (cmiRNAs) profiles of individuals exposed to high altitude to explore the altitude acclimatization in humans.
Project description:Understanding molecular mechanism associated with high altitude exposure during acclimatization/adaptation/maladaptation. Data reveals specific components of the complex molecular circuitry underlying high altitude pulmonary edema.
Project description:Purpose: The goal of this study was to compare the microRNA transcriptomes of four high-altitude vertebrates and their low-altitude relatives for six organs (heart,liver,spleen,lung,kidney and muscle). Methods: Three adult females for each population of the five species from distinct altitudes (600 m, 2000 m, and 3000 m) were humanely killed to ameliorate suffering. A piece of tissue fragments from six organs including heart, liver, spleen, lung, kidney and skeletal muscle(longissimus muscle for pig, cattle, yak and sheep, and pectoral muscle for chicken) were used to extract total RNA. Small RNA libraries were constructed using the Illumina TruSeq Small RNA Sample Prep kit and sequenced on the Illumina HiSeq 2500. The raw data were submitted to miRDeep2.0 to detect miRNAs for each species with default parameters. Results: we detected 2,036 mature miRNAs in five species and identified 49 orthologues among vertebrate, 111 orthologues in artiodactyla and 171 orthologues in ruminant . Conclusions: We identified comparable numbers of miRNAs in each species.
Project description:This study evaluates genetic and phenotypic variation in the high altitude Colla population living in the Argentinean Andes above 3500 m. They were compared to the Wichà population living in the nearby lowlands of the Gran Chaco region. This study attempts to pinpoint evolutionary mechanisms underlying adaptation to hypobaric hypoxia. We have genotyped 25 individuals from both populations for 730,525 SNPs. DNA from 25 saliva samples from Collas living >3500 m and 25 saliva samples from Wichà living <500 m from the Province of Salta in Argentina was genotyped
Project description:Additional to GSE1807 A comparative analysis, by expression profiling of maize, was performed to identify novel components in the mechanisms of maize responses to UV-B. Five high-altitude landraces grown from 2,000 to 3,400 m naturally receive higher UV-B fluence than plants at lower altitudes and similar latitudes. These high-altitude landraces were compared directly with a low-altitude line and with literature reports for other temperate maize lines. A microarray analysis demonstrated that among the UV-B responsive transcripts, several types of gene implicated in chromatin remodeling are differentially expressed before and after UV-B treatment in high-altitude lines. RNAi transgenic plants with lower expression of four such chromatin-associated genes exhibited hypersensitivity to UV-B by measurements of leaf arching, increased leaf chlorosis and necrosis, and altered UV-B regulation of selected genes. These results collectively suggest that genes involved in chromatin remodeling are crucial for UV-B acclimation and that some high-altitude lines exhibit adaptations to this challenge.