Project description:Sakha – an area connecting South and Northeast Siberia – is significant for understanding the history of peopling of Northeast Eurasia and the Americas. Previous studies have shown a genetic contiguity between Siberia and East Asia and the key role of South Siberia in the colonization of Siberia. We report the results of a high-resolution phylogenetic analysis of 701 mtDNAs and 318 Y chromosomes from five native populations of Sakha (Yakuts, Evenks, Evens, Yukaghirs and Dolgans) and of the analysis of more than 500,000 autosomal SNPs of 758 individuals from 55 populations, including 40 previously unpublished samples from Siberia. Phylogenetically terminal clades of East Asian mtDNA haplogroups C and D and Y-chromosome haplogroups N1c, N1b and C3, constituting the core of the gene pool of the native populations from Sakha, connect Sakha and South Siberia. Analysis of autosomal SNP data confirms the genetic continuity between Sakha and South Siberia. Maternal lineages D5a2a2, C4a1c, C4a2, C5b1b and the Yakut-specific STR sub-clade of Y-chromosome haplogroup N1c can be linked to a migration of Yakut ancestors, while the paternal lineage C3c was most likely carried to Sakha by the expansion of the Tungusic people. MtDNA haplogroups Z1a1b and Z1a3, present in Yukaghirs, Evens and Dolgans, show traces of different and probably more ancient migration(s). Analysis of both haploid loci and autosomal SNP data revealed only minor genetic components shared between Sakha and the extreme Northeast Siberia. Although the major part of West Eurasian maternal and paternal lineages in Sakha could originate from recent admixture with East Europeans, mtDNA haplogroups H8, H20a and HV1a1a, as well as Y-chromosome haplogroup J, more probably reflect an ancient gene flow from West Eurasia through Central Asia and South Siberia. Our high-resolution phylogenetic dissection of mtDNA and Y-chromosome haplogroups as well as analysis of autosomal SNP data suggests that Sakha was colonized by repeated expansions from South Siberia with minor gene flow from the Lower Amur/Southern Okhotsk region and/or Kamchatka. The minor West Eurasian component in Sakha attests to both recent and ongoing admixture with East Europeans and an ancient gene flow from West Eurasia.
2013-06-26 | GSE46828 | GEO
Project description:Protist communities in saline and hypersaline continental waters
Project description:Sakha M-bM-^@M-^S an area connecting South and Northeast Siberia M-bM-^@M-^S is significant for understanding the history of peopling of Northeast Eurasia and the Americas. Previous studies have shown a genetic contiguity between Siberia and East Asia and the key role of South Siberia in the colonization of Siberia. We report the results of a high-resolution phylogenetic analysis of 701 mtDNAs and 318 Y chromosomes from five native populations of Sakha (Yakuts, Evenks, Evens, Yukaghirs and Dolgans) and of the analysis of more than 500,000 autosomal SNPs of 758 individuals from 55 populations, including 40 previously unpublished samples from Siberia. Phylogenetically terminal clades of East Asian mtDNA haplogroups C and D and Y-chromosome haplogroups N1c, N1b and C3, constituting the core of the gene pool of the native populations from Sakha, connect Sakha and South Siberia. Analysis of autosomal SNP data confirms the genetic continuity between Sakha and South Siberia. Maternal lineages D5a2a2, C4a1c, C4a2, C5b1b and the Yakut-specific STR sub-clade of Y-chromosome haplogroup N1c can be linked to a migration of Yakut ancestors, while the paternal lineage C3c was most likely carried to Sakha by the expansion of the Tungusic people. MtDNA haplogroups Z1a1b and Z1a3, present in Yukaghirs, Evens and Dolgans, show traces of different and probably more ancient migration(s). Analysis of both haploid loci and autosomal SNP data revealed only minor genetic components shared between Sakha and the extreme Northeast Siberia. Although the major part of West Eurasian maternal and paternal lineages in Sakha could originate from recent admixture with East Europeans, mtDNA haplogroups H8, H20a and HV1a1a, as well as Y-chromosome haplogroup J, more probably reflect an ancient gene flow from West Eurasia through Central Asia and South Siberia. Our high-resolution phylogenetic dissection of mtDNA and Y-chromosome haplogroups as well as analysis of autosomal SNP data suggests that Sakha was colonized by repeated expansions from South Siberia with minor gene flow from the Lower Amur/Southern Okhotsk region and/or Kamchatka. The minor West Eurasian component in Sakha attests to both recent and ongoing admixture with East Europeans and an ancient gene flow from West Eurasia. 40 samples were analysed with the Illumina platform Human660W-Quad v1.0 and are described herein.
Project description:Abstract Hypersaline lakes are of immense ecological value as they niche some of the most exclusive extremophilic communities dominated by bacterial and archaeal domains, with few eukaryotic algal representatives. A handful reports describe Picocystis as a key primary producer with great production rates in extremely saline habitats. An extremely haloalkaliphilic picoalgal strain, Picocystis salinarum SLJS6 isolated from hypersaline lake Sambhar, Rajasthan, India, grew robustly in an enriched soda lake medium containing mainly Na2CO3, 50 g/L; NaHCO3, 50g/L, NaCl, 50 g/L (salinity ≈150 ‰) at pH 10. To elucidate the molecular basis of such tolerance to high inorganic carbon and NaCl concentrations, a high-throughput LFQ (label-free quantitation) based quantitative proteomics approach was applied. Out of the total 383 proteins identified in treated samples, 225 were Differentially abundant proteins (DAPs), of which 150 were statistically significant (p value <0.05) including 70 upregulated and 64 downregulated proteins after 3 days of salt and alkalinity stress. Gene ontology analysis was done to annotate and classify the DAPs into functional groups. The analysis linked most DAPs to photosynthesis, oxidative phosphorylation, glucose metabolism and ribosomal structural components envisaging that photosynthesis and ATP synthesis were central to the alkalinity-salinity response. Key components of photosynthetic machinery like photosystem reaction centres, ATP synthase, Rubisco, Fructose-bisphosphate aldolase were significantly upregulated. Enzymes Peptidylprolyl isomerases (PPIase), important for correct protein folding showed remarkable marked-up regulation along with other chaperon proteins indicating their role in alleviating stress. Enhanced photosynthetic activity exhibited by Picocystis salinarum in highly saline-alkaline condition is noteworthy as photosynthesis is suppressed by salt stress in most photosynthetic organisms. This study provided the first evidence of a tailored regulatory mechanism of alkalinity and salt tolerance in extremophilic alga P. salinarum, potentially unraveling the basis of resilience in this not so known organism and paves the way for a promising future production host and model or¬ganism for deciphering the molecular mechanisms of os¬motic stress responses.
Project description:The intact polar lipids of archaea from hypersaline lakes
https://doi.org/10.1016/j.syapm.2021.126249
https://doi.org/10.1099/ijsem.0.003506
2022-07-07 | MSV000089830 | MassIVE
Project description:Bacterial community structure and metabolic potential in microbialite-forming mats from South Australian saline-to-hypersaline lakes