Introduction Tibetan sheep,economically important animals on the Qinghai–Tibet Plateau,have diversified into numerous local breeds with unique characteristics through prolonged environmental adaptation and selective ...Introduction Tibetan sheep,economically important animals on the Qinghai–Tibet Plateau,have diversified into numerous local breeds with unique characteristics through prolonged environmental adaptation and selective breeding.However,most current research focuses on one or two breeds,and lacks a comprehensive representa-tion of the genetic diversity across multiple Tibetan sheep breeds.This study aims to fill this gap by investigating the genetic structure,diversity and high-altitude adaptation of 6 Tibetan sheep breeds using whole-genome rese-quencing data.Results Six Tibetan sheep breeds were investigated in this study,and whole-genome resequencing data were used to investigate their genetic structure and population diversity.The results showed that the 6 Tibetan sheep breeds exhibited distinct separation in the phylogenetic tree;however,the levels of differentiation among the breeds were minimal,with extensive gene flow observed.Population structure analysis broadly categorized the 6 breeds into 3 distinct ecological types:plateau-type,valley-type and Euler-type.Analysis of unique single-nucleotide polymor-phisms(SNPs)and selective sweeps between Argali and Tibetan sheep revealed that Tibetan sheep domestication was associated primarily with sensory and signal transduction,nutrient absorption and metabolism,and growth and reproductive characteristics.Finally,comprehensive analysis of selective sweep and transcriptome data sug-gested that Tibetan sheep breeds inhabiting different altitudes on the Qinghai–Tibet Plateau adapt by enhancing cardiopulmonary function,regulating body fluid balance through renal reabsorption,and modifying nutrient diges-tion and absorption pathways.Conclusion In this study,we investigated the genetic diversity and population structure of 6 Tibetan sheep breeds in Qinghai Province,China.Additionally,we analyzed the domestication traits and investigated the unique adapta-tion mechanisms residing varying altitudes in the plateau region of Tibetan sheep.This study provides valuable insights into the evolutionary processes of Tibetan sheep in extreme environments.These findings will also contribute to the preservation of genetic diversity and offer a foundation for Tibetan sheep diversity preservation and plateau animal environmental adaptation mechanisms.展开更多
Maize,a global food crop,was domesticated from its wild ancestor teosinte approximately 9000 years ago near the Balsas river in southwestern Mexico.Through natural and artificial selection of key traits,maize has expa...Maize,a global food crop,was domesticated from its wild ancestor teosinte approximately 9000 years ago near the Balsas river in southwestern Mexico.Through natural and artificial selection of key traits,maize has expanded widely across the world[1-3].Mesocotyl is an important organ for cereal crops that bridges the coleoptilar node and basal part of the seminal root[4].The elongation of mesocotyl during seed germination pushes the buds out of the soil,thus playing a key role in determining the successful early seedling establishment.Internal and environmental signals,such as phytohormones and light,regulate the growth of maize mesocotyl[1,4-8].展开更多
Humans have been exposed to many environmental challenges since their evolutionary origins in Africa and subsequent migrations to the rest of the world. A severe environmental challenge to human migrants was hypoxia c...Humans have been exposed to many environmental challenges since their evolutionary origins in Africa and subsequent migrations to the rest of the world. A severe environmental challenge to human migrants was hypoxia caused by low barometric oxygen pressure at high altitudes. Several genome-wide scans have elucidated the genetic basis of human high-altitude adaptations.However, the dearth of functional variant information has led to the successful association of only a few candidate genes. In the present study, we employed a candidate gene approach and re-sequenced the EDAR locus in 45 Tibetan individuals to identify mutations involved in hypoxia adaptation. We identified 10 and five quantitative trait-associated mutations for oxygen saturation (SaO_2) and blood platelet count, respectively, at the EDAR locus. Among these, rs10865026 and rs3749110 (associated with SaO_2 and platelet count, respectively) were identified as functional candidate targets. These data demonstrate that EDAR has undergone natural selection in recent human history and indicate an important role of EDAR variants in Tibetan high-altitude adaptations.展开更多
Microblade assemblages are among the most common prehistoric archaeological materials found on the Tibetan Plateau(TP)and are thought to indicate large scale migration to and settlement of the TP.Few microblade sites,...Microblade assemblages are among the most common prehistoric archaeological materials found on the Tibetan Plateau(TP)and are thought to indicate large scale migration to and settlement of the TP.Few microblade sites,however,have been systematically excavated,especially in the remotest,highest-elevation regions of the TP.The timing of the large-scale arrival,spread,and permanent settlement of people on the TP therefore remains controversial.In this paper,we report on a recently excavated site,Locality 3 of the Nwya Devu Site(ND3),located at 4600 meters above sea level(masl),near the shore of Ngoin Lake,on the interior TP.Our analyses reveal a fairly typical microblade technological orientation and two types of microblade cores:wedge-shaped and semi-conical,which are similar to those found throughout North China.Using Optically Stimulated Luminescence(OSL)dating and AMS^(14)C dating,the age of ND3 ranges from 11 to 10 ka.This date range indicates ND3 is the oldest microblade site yet recorded in the remote,high-elevation regions of the TP and thus provides important information about when and how hunter-gatherers using microblades began exploiting the higher altitudes of the TP.Taken together,studies at ND3 and throughout the TP suggest that a microblade adaptation is associated with the first prolonged human occupation of the plateau and that microblades played a significant role in mediating the risks and facilitating the mobility necessary to permanently inhabit the TP.展开更多
基金supported by the Natural Science Foundation of Qinghai Province(No.2022-ZJ-901)the National Breeding Joint Research Project。
文摘Introduction Tibetan sheep,economically important animals on the Qinghai–Tibet Plateau,have diversified into numerous local breeds with unique characteristics through prolonged environmental adaptation and selective breeding.However,most current research focuses on one or two breeds,and lacks a comprehensive representa-tion of the genetic diversity across multiple Tibetan sheep breeds.This study aims to fill this gap by investigating the genetic structure,diversity and high-altitude adaptation of 6 Tibetan sheep breeds using whole-genome rese-quencing data.Results Six Tibetan sheep breeds were investigated in this study,and whole-genome resequencing data were used to investigate their genetic structure and population diversity.The results showed that the 6 Tibetan sheep breeds exhibited distinct separation in the phylogenetic tree;however,the levels of differentiation among the breeds were minimal,with extensive gene flow observed.Population structure analysis broadly categorized the 6 breeds into 3 distinct ecological types:plateau-type,valley-type and Euler-type.Analysis of unique single-nucleotide polymor-phisms(SNPs)and selective sweeps between Argali and Tibetan sheep revealed that Tibetan sheep domestication was associated primarily with sensory and signal transduction,nutrient absorption and metabolism,and growth and reproductive characteristics.Finally,comprehensive analysis of selective sweep and transcriptome data sug-gested that Tibetan sheep breeds inhabiting different altitudes on the Qinghai–Tibet Plateau adapt by enhancing cardiopulmonary function,regulating body fluid balance through renal reabsorption,and modifying nutrient diges-tion and absorption pathways.Conclusion In this study,we investigated the genetic diversity and population structure of 6 Tibetan sheep breeds in Qinghai Province,China.Additionally,we analyzed the domestication traits and investigated the unique adapta-tion mechanisms residing varying altitudes in the plateau region of Tibetan sheep.This study provides valuable insights into the evolutionary processes of Tibetan sheep in extreme environments.These findings will also contribute to the preservation of genetic diversity and offer a foundation for Tibetan sheep diversity preservation and plateau animal environmental adaptation mechanisms.
基金supported by the National Natural Science Foun-dation of China(31971954,32201720,and 32321005)the China Postdoctoral Science Foundation(2022M711267)the Natural Science Foundation of Hubei province,China(2023AFB939).
文摘Maize,a global food crop,was domesticated from its wild ancestor teosinte approximately 9000 years ago near the Balsas river in southwestern Mexico.Through natural and artificial selection of key traits,maize has expanded widely across the world[1-3].Mesocotyl is an important organ for cereal crops that bridges the coleoptilar node and basal part of the seminal root[4].The elongation of mesocotyl during seed germination pushes the buds out of the soil,thus playing a key role in determining the successful early seedling establishment.Internal and environmental signals,such as phytohormones and light,regulate the growth of maize mesocotyl[1,4-8].
基金supported by the National Natural Science Foundation of China (91131905, 30890030)Strategic Priority Research Program of the Chinese Academy of Sciences (XDB13020500)Weng Hongwu Original Scientific Research Foundation, Peking University
文摘Humans have been exposed to many environmental challenges since their evolutionary origins in Africa and subsequent migrations to the rest of the world. A severe environmental challenge to human migrants was hypoxia caused by low barometric oxygen pressure at high altitudes. Several genome-wide scans have elucidated the genetic basis of human high-altitude adaptations.However, the dearth of functional variant information has led to the successful association of only a few candidate genes. In the present study, we employed a candidate gene approach and re-sequenced the EDAR locus in 45 Tibetan individuals to identify mutations involved in hypoxia adaptation. We identified 10 and five quantitative trait-associated mutations for oxygen saturation (SaO_2) and blood platelet count, respectively, at the EDAR locus. Among these, rs10865026 and rs3749110 (associated with SaO_2 and platelet count, respectively) were identified as functional candidate targets. These data demonstrate that EDAR has undergone natural selection in recent human history and indicate an important role of EDAR variants in Tibetan high-altitude adaptations.
基金supported by the National Key Research and Development Project of China(Grant No.2021YFC1523603)the Second Tibetan Plateau Scientific Expedition and Research(Grant No.2019QZKK0601)+1 种基金the National Natural Science Foundation of China(Grant Nos.42072033&41977380)the National Social Science Foundation of China(Grant Nos.23&ZD268&21@WTK001)。
文摘Microblade assemblages are among the most common prehistoric archaeological materials found on the Tibetan Plateau(TP)and are thought to indicate large scale migration to and settlement of the TP.Few microblade sites,however,have been systematically excavated,especially in the remotest,highest-elevation regions of the TP.The timing of the large-scale arrival,spread,and permanent settlement of people on the TP therefore remains controversial.In this paper,we report on a recently excavated site,Locality 3 of the Nwya Devu Site(ND3),located at 4600 meters above sea level(masl),near the shore of Ngoin Lake,on the interior TP.Our analyses reveal a fairly typical microblade technological orientation and two types of microblade cores:wedge-shaped and semi-conical,which are similar to those found throughout North China.Using Optically Stimulated Luminescence(OSL)dating and AMS^(14)C dating,the age of ND3 ranges from 11 to 10 ka.This date range indicates ND3 is the oldest microblade site yet recorded in the remote,high-elevation regions of the TP and thus provides important information about when and how hunter-gatherers using microblades began exploiting the higher altitudes of the TP.Taken together,studies at ND3 and throughout the TP suggest that a microblade adaptation is associated with the first prolonged human occupation of the plateau and that microblades played a significant role in mediating the risks and facilitating the mobility necessary to permanently inhabit the TP.
