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Single-nucleotide polymorphisms and copy number variations drive adaptive evolution to freezing stress in a subtropical evergreen broadleaved tree:Hexaploid wild Camellia oleifera 被引量:1
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作者 Haoxing Xie Kaifeng Xing +3 位作者 Jun Zhou Yao Zhao Jian Zhang Jun Rong 《Plant Diversity》 2025年第2期214-228,共15页
Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wil... Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wild C.oleifera can serve as a case for studying the molecular bases of adaptive evolution to freezing stress.Here,47 wild C.oleifera from 11 natural distribution sites in China and 4 relative species of C.oleifera were selected for genome sequencing.“Min Temperature of Coldest Month”(BIO6)had the highest comprehensive contribution to wild C.oleifera distribution.The population genetic structure of wild C.oleifera could be divided into two groups:in cold winter(BIO6≤0℃)and warm winter(BIO6>0℃)areas.Wild C.oleifera in cold winter areas might have experienced stronger selection pressures and population bottlenecks with lower N_(e) than those in warm winter areas.155 singlenucleotide polymorphisms(SNPs)were significantly correlated with the key bioclimatic variables(106 SNPs significantly correlated with BIO6).Twenty key SNPs and 15 key copy number variation regions(CNVRs)were found with genotype differentiation>50%between the two groups of wild C.oleifera.Key SNPs in cis-regulatory elements might affect the expression of key genes associated with freezing tolerance,and they were also found within a CNVR suggesting interactions between them.Some key CNVRs in the exon regions were closely related to the differentially expressed genes under freezing stress.The findings suggest that rich SNPs and CNVRs in polyploid trees may contribute to the adaptive evolution to freezing stress. 展开更多
关键词 adaptive evolution Camellia oleifera Copy number variations Freezing stress POLYPLOID Single-nucleotide polymorphisms
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Canalization of globins in the adaptive evolution of birds
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作者 Xiaojia Zhu Le Yang +5 位作者 Quanjian Tao Xiran Wang Ghulam Nabi Fumin Lei Xiaoping Yu Dongming Li 《Avian Research》 2025年第4期764-774,共11页
The globin superfamily,central to oxygen(O_(2))cascade dynamics,exemplifies how canalization—evolutionary stabilization of phenotypic traits—enables vertebrates to thrive in extreme environments.In birds,hemoglobins... The globin superfamily,central to oxygen(O_(2))cascade dynamics,exemplifies how canalization—evolutionary stabilization of phenotypic traits—enables vertebrates to thrive in extreme environments.In birds,hemoglobins(Hbs)serve as a paradigm of this process,with structural and functional canalization underpinning their exceptional aerobic capacity and elevational diversification.Despite significant advances of globins in our understanding of avian aerobic adaptation,a comprehensive synthesis of functional diversity,molecular evolution,and structural innovation is essential to fully elucidate their canalized roles in O_(2)homeostasis.Integrating perspectives on globin functional diversity and structural evolution,this review examines how chance(mutation/fixation biases)and contingency(historical genetic/epistatic constraints)shape Hb divergence and parallelism,thereby bridging molecular mechanisms with physiological adaptation in birds.We highlight how avian Hbs,canalized through compensatory substitutions and allosteric regulation,achieves a balance between evolutionary robustness and adaptive plasticity.However,critical gaps remain persist:the roles of understudied globins(e.g.,neuroglobin,globin E)and the mechanisms of genetic assimilation in migratory taxa.We propose an integrative framework that incorporates ecological divergence(elevation,flight endurance),phylogenetic timescales,and systems biology to unravel how canalization directs adaptive compromise.By focusing on birds within the amniotes,this synthesis advances a cohesive model for vertebrate evolution,wherein canalized globins reconcile metabolic precision with ecological innovation.Ultimately,this review refines hypotheses of O_(2)cascade evolution and calls for cross-disciplinary studies to decode the genetic and physiological architecture underlying adaptive canalization in extreme environments. 展开更多
关键词 adaptive evolution Genetic canalization Globin superfamily HEMOGLOBINS Oxygen cascade Structural evolution
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Genomics and morphometrics reveal the adaptive evolution of pikas 被引量:1
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作者 Rui-Xiang Tang Jiao Wang +13 位作者 Yi-Fei Li Cheng-Ran Zhou Guan-Liang Meng Feng-Jun Li Yue Lan Megan Price Lars Podsiadlowski Yan Yu Xu-Ming Wang Yin-Xun Liu Bi-Song Yue Shan-Lin Liu Zhen-Xin Fan Shao-Ying Liu 《Zoological Research》 SCIE CAS CSCD 2022年第5期813-826,共14页
Pikas(Lagomorpha:Ochotonidae)are small mouselike lagomorphs.To investigate their adaptation to different ecological environments during their dispersal from the Qinghai-Xizang(Tibet)Plateau(QTP),we collected 226 pikas... Pikas(Lagomorpha:Ochotonidae)are small mouselike lagomorphs.To investigate their adaptation to different ecological environments during their dispersal from the Qinghai-Xizang(Tibet)Plateau(QTP),we collected 226 pikas and measured 20 morphological characteristics and recorded habitat information.We also sequenced the genome of 81specimens,representing 27 putative pika species.The genome-wide tree based on 4?090 coding genes identified five subgenera,i.e.,Alienauroa,Conothoa,Lagotona,Ochotona,and Pika,consistent with morphometric data.Morphologically,Alienauroa and Ochotona had similar traits,including smaller size and earlier divergence time compared to other pikas.Consistently,the habitats of Alienauroa and Ochotona differed from those of the remaining subgenera.Phylogenetic signal analysis detected 83 genes significantly related to morphological characteristics,including several visual and hearingrelated genes.Analysis of shared amino acid substitutions and positively selected genes(PSGs)in Alienauroa and Ochotona identified two genes,i.e.,mitochondrial function-related TSFM(p.Q155E)and low-light visual sensitivity-related PROM1(p.H419Y).Functional experiments demonstrated that TSFM-155E significantly enhanced mitochondrial function compared to TSFM-155Q in other pikas,and PROM1-419Y decreased the modeling of dynamic intracellular chloride efflux upon calcium uptake.Alienauroa and Ochotona individuals mostly inhabit different environments(e.g.,subtropical forests)than other pikas,suggesting that a shift from the larger ancestral type and changes in sensory acuity and energy enhancement may have been required in their new environments.This study increases our understanding of the evolutionary history of pikas. 展开更多
关键词 Pikas GENOMICS MORPHOMETRICS adaptive evolution Sensory and energy functions
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Adaptive evolution of rbcL in Reaumuria soon garica(Tamaricaceae) 被引量:1
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作者 ChaoJu Qian MengHe Gu +4 位作者 HengXia Yin Yong Shi ChengLiang Yin Xia Yan XiaoFei Ma 《Research in Cold and Arid Regions》 CSCD 2017年第1期78-88,共11页
In the field of phylogenetic analyses, the rbcL gene encoded large subunit Ribulose-1,5-biphosphate carboxylase/oxygenase (Rubisco, EC4.1.1.39), which plays a crucial role in the process of photosynthesis for most ... In the field of phylogenetic analyses, the rbcL gene encoded large subunit Ribulose-1,5-biphosphate carboxylase/oxygenase (Rubisco, EC4.1.1.39), which plays a crucial role in the process of photosynthesis for most terrestrial plants, has been considered to be conserved; however, recent controversy regarding rbcL conservation has appeared since it was proposed to be under natural selection within all principal lineages of land plants. In this study, by examining the variation of DNA and protein sequences among 17 species in the family Tamaricaceae, three nonsynonymous mutations were identified to be under positive selection. The favored sites were located in the alph-helix domains of Rubisco, with decreased hydrophobicity and increased entropy, which could facilitate C〇 2 penetration into the active site of Rubisco. We also found that the expression level of rbcL in different genotypes of Reaumuria soongarica shifted in response to various stresses such as drought, temperature, salt, and light. This study not only sheds light on the functional/structural features of Rubisco in the evolution scenarios from 〇 3-like into C4 in Tamaricaceae but also provides useful information on directing genetic performance to enhance photosynthesis efficiency of desert plants for sustaining fragile desert ecosystems; fur-thermore, it promotes the ability to cope with desert aridification and global warming. 展开更多
关键词 rbcL gene Reaumuria soongarica] Tamaricaceae adaptive evolution
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Acetic acid-and furfural-based adaptive evolution of Saccharomyces cerevisiae strains for improving stress tolerance and lignocellulosic ethanol production
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作者 Omama Rehman Youduo Wu +7 位作者 Quan Zhang Jin Guo Cuihuan Sun Huipeng Gao Yaqing Xu Rui Xu Ayesha Shahid Chuang Xue 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第8期26-33,共8页
Acetic acid and furfural are known as prevalent inhibitors deriving from pretreatment during lignocellulosic ethanol production.They negatively impact cell growth,glucose uptake and ethanol biosynthesis of Saccharomyc... Acetic acid and furfural are known as prevalent inhibitors deriving from pretreatment during lignocellulosic ethanol production.They negatively impact cell growth,glucose uptake and ethanol biosynthesis of Saccharomyces cerevisiae strains.Development of industrial S.cerevisiae strains with high tolerance towards these inhibitors is thus critical for efficient lignocellulosic ethanol production.In this study,the acetic acid or furfural tolerance of different S.cerevisiae strains could be significantly enhanced after adaptive evolution via serial cultivation for 40 generations under stress conditions.The acetic acid-based adaptive strain SPSC01-TA9 produced 30.5 g·L^(-1)ethanol with a yield of 0.46 g·g^(-1)in the presence of 9 g·L^(-1)acetic acid,while the acetic acid/furfural-based adaptive strain SPSC01-TAF94 produced more ethanol of 36.2 g·L^(-1)with increased yield up to 0.49 g·g^(-1)in the presence of both 9 g·L^(-1)acetic acid and 4 g·L^(-1)furfural.Significant improvements were also observed during non-detoxified corn stover hydrolysate culture by SPSC01-TAF94,which achieved ethanol production and yield of 29.1 g·L^(-1)and 0.49 g·g^(-1),respectively,the growth and fermentation efficiency of acetic acid/furfural-based adaptive strain in hydrolysate was 95%higher than those of wildtype strains,indicating the acetic acid-and furfural-based adaptive evolution strategy could be an effective approach for improving lignocellulosic ethanol production.The adapted strains developed in this study with enhanced tolerance against acetic acid and furfural could be potentially contribute to economically feasible and sustainable lignocellulosic biorefinery. 展开更多
关键词 Saccharomyces cerevisiae Lignocellulosic ethanol production adaptive evolution Acetic acid FURFURAL
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Genomic Mutations Within the Host Microbiome: Adaptive Evolution or Purifying Selection
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作者 Jiachao Zhang Rob Knight 《Engineering》 SCIE EI CAS CSCD 2023年第1期96-102,共7页
Next-generation sequencing technology has transformed our ability to assess the taxonomic composition functions of host-associated microbiota and microbiomes. More human microbiome research projects—particularly thos... Next-generation sequencing technology has transformed our ability to assess the taxonomic composition functions of host-associated microbiota and microbiomes. More human microbiome research projects—particularly those that explore genomic mutations within the microbiome—will be launched in the next decade. This review focuses on the coevolution of microbes within a microbiome, which shapes strain-level diversity both within and between host species. We also explore the correlation between microbial genomic mutations and common metabolic diseases, and the adaptive evolution of pathogens and probiotics during invasion and colonization. Finally, we discuss advances in methods and algorithms for annotating and analyzing microbial genomic mutations. 展开更多
关键词 Gut microbiota Genomic mutations adaptive evolution Purifying selection Single-nucleoti de variants
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Genetic variation for adaptive evolution in response to changed environments in plants
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作者 Jing Hou Meng Liu +3 位作者 Kai Yang Bao Liu Huanhuan Liu Jianquan Liu 《Journal of Integrative Plant Biology》 2025年第9期2265-2293,共29页
Plants adapt to their local environments through natural or artificial selection of optimal phenotypes.Recent advances in genomics and computational biology,which integrate phenotypic and multi-omics data,have facilit... Plants adapt to their local environments through natural or artificial selection of optimal phenotypes.Recent advances in genomics and computational biology,which integrate phenotypic and multi-omics data,have facilitated the rapid identification of key genes and allelic variations that underlie these adaptive evolutionary processes.Under-standing the underlying molecular mechanisms has significantly enhanced our knowledge of how plants respond to changed habitats,including various biotic and abiotic stresses.In this review,we highlight recent progress in elucidating the ge-netic basis of phenotypic variation in morphological traits and stress responses,as well as the emer-gence of new ecotypes,subspecies,and species during adaptive evolution across varied environ-ments.This occurs through allelic divergences in both coding and non-coding regions in both model and non-model plants.Furthermore,the terrestrial-ization and early diversification of land plants in-volved the acquisition of additional genes,primarily through horizontal gene transfer and whole-genome duplication,which facilitated the development of complex molecular pathways to adapt to increas-ingly diverse environments.Finally,we discuss emerging trends and prospects for exploring and utilizing beneficial alleles for environmental adap-tation,to guide crop breeding efforts in response to global climate change. 展开更多
关键词 abiotic stress adaptive evolution alleles biotic stress genetic variations morphological traits
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The applications and potential prospects of paleogenomics in investigating the demographic changes and adaptive evolution of the giant panda
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作者 Kexin LI Zehui CHEN Qiaomei FU 《Science China Earth Sciences》 2025年第7期2061-2072,共12页
The giant panda(Ailuropoda melanoleuca)is a rare species endemic to China,and also serves as a flagship species for global biodiversity conservation.Elucidating its evolutionary history is of great significance for co... The giant panda(Ailuropoda melanoleuca)is a rare species endemic to China,and also serves as a flagship species for global biodiversity conservation.Elucidating its evolutionary history is of great significance for conservation efforts.However,knowledge about the demographic changes and adaptive evolution of the giant panda remains limited.Paleogenomic research,with its broad temporal and geographic coverage,provides a novel perspective for addressing these questions.Given this,this study discusses three core topics related to the evolution of the giant panda.Firstly,we systematically consolidated the fossil records from the Late Miocene to the Holocene,along with their related studies,illustrating the impact of climatic and anthropogenic factors on the demographic history of the giant panda.In particular,climate change served as the primary driver of population fluctuations during the Pleistocene,leading to two episodes of population expansion and bottleneck.Additionally,human activities played a significant role in population divergence and demographic changes during the Holocene.Secondly,we also elucidated the adaptive process of the giant panda in terms of their highly specialized diet,highlighting long-term adaptation in morphology,genetics,and gut microbiota composition,which have led to its unique adaptive traits.Finally,the potential and significance of the paleogenomic studies in deepening our understanding of the demographic history and adaptive evolution of the giant panda were discussed.Meanwhile,this study demonstrated the potential of paleogenomic approaches for resolving species identification and obtaining individual-level information from fossil specimens,using ancient samples excavated from Baling in Shaanxi and Bamianshan in Hunan as case studies. 展开更多
关键词 Giant panda Paleogenomics Demographic changes adaptive evolution Species and individual identification
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Molecular mechanisms of adaptive evolution in wild animals and plants 被引量:15
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作者 Yibo Hu Xiaoping Wang +11 位作者 Yongchao Xu Hui Yang Zeyu Tong Ran Tian Shaohua Xu Li Yu Yalong Guo Peng Shi Shuangquan Huang Guang Yang Suhua Shi Fuwen Wei 《Science China(Life Sciences)》 SCIE CAS CSCD 2023年第3期453-495,共43页
Wild animals and plants have developed a variety of adaptive traits driven by adaptive evolution,an important strategy for species survival and persistence.Uncovering the molecular mechanisms of adaptive evolution is ... Wild animals and plants have developed a variety of adaptive traits driven by adaptive evolution,an important strategy for species survival and persistence.Uncovering the molecular mechanisms of adaptive evolution is the key to understanding species diversification,phenotypic convergence,and inter-species interaction.As the genome sequences of more and more non-model organisms are becoming available,the focus of studies on molecular mechanisms of adaptive evolution has shifted from the candidate gene method to genetic mapping based on genome-wide scanning.In this study,we reviewed the latest research advances in wild animals and plants,focusing on adaptive traits,convergent evolution,and coevolution.Firstly,we focused on the adaptive evolution of morphological,behavioral,and physiological traits.Secondly,we reviewed the phenotypic convergences of life history traits and responding to environmental pressures,and the underlying molecular convergence mechanisms.Thirdly,we summarized the advances of coevolution,including the four main types:mutualism,parasitism,predation and competition.Overall,these latest advances greatly increase our understanding of the underlying molecular mechanisms for diverse adaptive traits and species interaction,demonstrating that the development of evolutionary biology has been greatly accelerated by multi-omics technologies.Finally,we highlighted the emerging trends and future prospects around the above three aspects of adaptive evolution. 展开更多
关键词 adaptive evolution adaptive trait coevolution comparative genomics convergent evolution genetic convergence molecular mechanism MUTUALISM PARASITISM phenotype convergence
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A Chromosome-level Genome Assembly of Wild Castor Provides New Insights into Its Adaptive Evolution in Tropical Desert 被引量:3
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作者 Jianjun Lu Cheng Pan +12 位作者 Wei Fan Wanfei Liu Huayan Zhao Donghai Li Sen Wang Lianlian Hu Bing He Kun Qian Rui Qin Jue Ruan Qiang Lin Shiyou Lü Peng Cui 《Genomics, Proteomics & Bioinformatics》 SCIE CAS CSCD 2022年第1期42-59,共18页
Wild castor grows in the high-altitude tropical desert of the African Plateau,a region known for high ultraviolet radiation,strong light,and extremely dry condition.To investigate the potential genetic basis of adapta... Wild castor grows in the high-altitude tropical desert of the African Plateau,a region known for high ultraviolet radiation,strong light,and extremely dry condition.To investigate the potential genetic basis of adaptation to both highland and tropical deserts,we generated a chromosome-level genome sequence assembly of the wild castor accession WT05,with a genome size of 316 Mb,a scaffold N50 of 31.93 Mb,and a contig N50 of 8.96 Mb,respectively.Compared with cultivated castor and other Euphorbiaceae species,the wild castor exhibits positive selection and gene family expansion for genes involved in DNA repair,photosynthesis,and abiotic stress responses.Genetic variations associated with positive selection were identified in several key genes,such as LIG1,DDB2,and RECG1,involved in nucleotide excision repair.Moreover,a study of genomic diversity among wild and cultivated accessions revealed genomic regions containing selection signatures associated with the adaptation to extreme environments.The identification of the genes and alleles with selection signatures provides insights into the genetic mechanisms underlying the adaptation of wild castor to the high-altitude tropical desert and would facilitate direct improvement of modern castor varieties. 展开更多
关键词 Ricinus communis L. adaptive evolution Selection signature Genetic variation Genome assembly
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Population genome of the newly discovered Jinchuan yak to understand its adaptive evolution in extreme environments and generation mechanism of the multirib trait 被引量:3
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作者 Daoliang LAN Wenhui JI +5 位作者 Xianrong XIONG Qiqi LIANG Wenye YAO Tserang-Donko MIPAM Jincheng ZHONG Jian LI 《Integrative Zoology》 SCIE CSCD 2021年第5期685-695,共11页
The adaptation and diversity of animals to the extreme environments of the Qinghai–Tibet Plateau(QTP)are typical materials to study adaptive evolution.The recently discovered Jinchuan yak population has many individu... The adaptation and diversity of animals to the extreme environments of the Qinghai–Tibet Plateau(QTP)are typical materials to study adaptive evolution.The recently discovered Jinchuan yak population has many individuals with multiple ribs.However,little is known about this yak’s origin,evolution,and the genetic mechanisms that formed its unique multirib trait.Here,we report a valuable population genome resource of the Jinchuan yak by resequencing the whole genome of 150 individuals.Population genetic polymorphism and structure analysis reveal that Jinchuan yak can be differentiated as a unique and original yak population among the domestic yak.Combined with geological change,the Jinchuan yak’s evolutionary origin is speculated to be about 6290 years ago,which may be related to the unique geographical environment of the eastern edge of the QTP during this period.Compared with other domestic yaks,this new population has 280 positively selected genes.The genes related to skeletal function hold a considerable and remarkable proportion,suggesting that the specific skeletal characteristics have been enhanced in the adaptive evolution of Jinchuan yak in the extreme plateau environment.The genome-wide association study has revealed that TUBA8 and TUBA4A,the genes that regulate the cytoskeleton,are potential genes associated with the multirib trait.Our findings provide a basis to further understand the generation mechanism of the adaptive evolution of this new population in high-altitude extreme environments and the multivertebrate trait of domestic animals. 展开更多
关键词 adaptive evolution genetic mechanism multirib trait Qinghai-Tibet Plateau YAK
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Genome assembly of autotetraploid Actinidia arguta highlights adaptive evolution and enables dissection of important economic traits 被引量:2
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作者 Xue-Mei Lu Xiao-Fen Yu +35 位作者 Guo-Qiang Li Ming-Hao Qu Huan Wang Chuang Liu Yu-Ping Man Xiao-Han Jiang Mu-Zi Li Jian Wang Qi-Qi Chen Rui Lei Cheng-Cheng Zhao Yun-Qiu Zhou Zheng-Wang Jiang Zuo-Zhou Li Shang Zheng Chang Dong Bai-Lin Wang Yan-Xiang Sun Hui-Qin Zhang Jie-Wei Li Quan-Hui Mo Ying Zhang Xin Lou Hai-Xu Peng Ya-Ting Yi He-Xin Wang Xiu-Jun Zhang Yi-Bo Wang Dan Wang Li Li Qiong Zhang Wen-Xia Wang Yongbo Liu Lei Gao Jin-Hu Wu Yan-Chang Wang 《Plant Communications》 SCIE CSCD 2024年第6期173-192,共20页
Actinidia arguta,the most widely distributed Actinidia species and the second cultivated species in the genus,can be distinguished from the currently cultivated Actinidia chinensis on the basis of its small and smooth... Actinidia arguta,the most widely distributed Actinidia species and the second cultivated species in the genus,can be distinguished from the currently cultivated Actinidia chinensis on the basis of its small and smooth fruit,rapid softening,and excellent cold tolerance.Adaptive evolution of tetraploid Actinidia species and the genetic basis of their important agronomic traits are still unclear.Here,we generated a chromosome-scale genome assembly of an autotetraploid male A.arguta accession.The genome assembly was 2.77 Gb in length with a contig N50 of 9.97 Mb and was anchored onto 116 pseudo-chromosomes.Resequencing and clustering of 101 geographically representative accessions showed that they could be divided into two geographic groups,Southern and Northern,which first diverged 12.9 million years ago.A.arguta underwent two prominent expansions and one demographic bottleneck from the midPleistocene climate transition to the late Pleistocene.Population genomics studies using paleoclimate data enabled us to discern the evolution of the species’adaptation to different historical environments.Three genes(AaCEL1,AaPME1,and AaDOF1)related to flesh softening were identified by multi-omics analysis,and their ability to accelerate flesh softening was verified through transient expression assays.A set of genes that characteristically regulate sexual dimorphism located on the sex chromosome(Chr3)or autosomal chromosomes showed biased expression during stamen or carpel development.This chromosome-level assembly of the autotetraploid A.arguta genome and the genes related to important agronomic traits will facilitate future functional genomics research and improvement of A.arguta. 展开更多
关键词 kiwiberry dioecism adaptive evolution PALEOCLIMATE GEA rapid softening
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Adaptive Evolution of cry Genes in Bacillus thuringiensis:Implications for Their Specificity Determination 被引量:1
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作者 Jin-Yu Wu Fang-Qing Zhao +3 位作者 Jie Bai Gang Deng Song Qin Qi-Yu Bao 《Genomics, Proteomics & Bioinformatics》 SCIE CAS CSCD 2007年第2期102-110,共9页
The cry gene family, produced during the late exponential phase of growth in Bacillus thuringiensis, is a large, still-growing family of homologous genes, in which each gene encodes a protein with strong specific acti... The cry gene family, produced during the late exponential phase of growth in Bacillus thuringiensis, is a large, still-growing family of homologous genes, in which each gene encodes a protein with strong specific activity against only one or a few insect species. Extensive studies are mostly focusing on the structural and functional relationships of Cry proteins, and have revealed several residues or domains that are important for the target recognition and receptor attachment. In this study, we have employed a maximum likelihood method to detect evidence of adaptive evolution in Cry proteins, and have identified 24 positively selected residues, which are all located in Domain Ⅱ or Ⅲ. Combined with known data from mutagenesis studies, the majority of these residues, at the molecular level, contribute much to the insect specificity determination. We postulate that the potential pressures driving the diversification of Cry proteins may be in an attempt to adapt for the "arm race" between δ-endotoxins and the targeted insects, or to enlarge their target spectra, hence result in the functional divergence. The sites identified to be under positive selection would provide targets for further structural and functional analyses on Cry proteins. 展开更多
关键词 adaptive evolution Bacillus thuringiensis Cry protein maximum likelihood method
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Local adaptive evolution of two distinct clades of Beijing and T families of Mycobacterium tuberculosis in Chongqing:a Bayesian population structure and phylogenetic study
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作者 Peng-Kuan Liang Chao Zheng +8 位作者 Xiao-Fang Xu Zhe-Ze Zhao Chang-Song Zhao Chang-He Li David Couvin Yann Reynaud Thierry Zozio Nalin Rastogiand Qun Sun 《Infectious Diseases of Poverty》 SCIE 2020年第3期134-135,共2页
Background:Beijing sub-pedigree 2(BSP2)and T sub-lineage 6(TSL6)are two clades belonging to Beijing and T family of Mycobacterium tuberculosis(MTB),respectively,defined by Bayesian population structure analysis based ... Background:Beijing sub-pedigree 2(BSP2)and T sub-lineage 6(TSL6)are two clades belonging to Beijing and T family of Mycobacterium tuberculosis(MTB),respectively,defined by Bayesian population structure analysis based on 24-loci mycobacterial interspersed repetitive unit-variable number of tandem repeats(MIRU-VNTR).Globally,over 99%of BSP2 and 89%of TSL6 isolates were distributed in Chongqing,suggesting their possible local adaptive evolution.The objective of this paper is to explore whether BSP2 and TSL6 originated by their local adaptive evolution from the specific isolates of Beijing and T families in Chongqing.Methods:The genotyping data of 16090 MTB isolates were collected from laboratory collection,published literatures and SITVIT database before subjected to Bayesian population structure analysis based on 24-loci MIRUVNTR.Spacer Oligonucleotide Forest(Spoligoforest)and 24-loci MIRU-VNTR-based minimum spanning tree(MST)were used to explore their phylogenetic pathways,with Bayesian demographic analysis for exploring the recent demographic change of TSL6.Results:Phylogenetic analysis suggested that BSP2 and TSL6 in Chongqing may evolve from BSP4 and TSL5,respectively,which were locally predominant in Tibet and Jiangsu,respectively.Spoligoforest showed that Beijing and T families were genetically distant,while the convergence of the MIRU-VNTR pattern of BSP2 and TSL6 was revealed by WebLogo.The demographic analysis concluded that the recent demographic change of TSL6 might take 111.25 years.Conclusions:BSP2 and TSL6 clades might originate from BSP4 and TSL5,respectively,by their local adaptive evolution in Chongqing.Our study suggests MIRU-VNTR be combined with other robust markers for a more comprehensive genotyping approach,especially for families of clades with the same MIRU-VNTR pattern. 展开更多
关键词 Mycobacterium tuberculosis Local adaptive evolution MIRU-VNTR Bayesian population structure analysis Phylogenetic analysis
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