Evolutionary convergence is one of the most striking examples of adaptation driven by natural selection.However, genomic evidence for convergent adaptation to extreme environments remains scarce.Here, we assembled ref...Evolutionary convergence is one of the most striking examples of adaptation driven by natural selection.However, genomic evidence for convergent adaptation to extreme environments remains scarce.Here, we assembled reference genomes of two alpine plants, Saussurea obvallata(Asteraceae)and Rheum alexandrae(Polygonaceae), with 37,938 and 61,463 annotated protein-coding genes. By integrating an additional five alpine genomes,we elucidated genomic convergence underlying high-altitude adaptation in alpine plants. Our results detected convergent contractions of diseaseresistance genes in alpine genomes, which might be an energy-saving strategy for surviving in hostile environments with only a few pathogens present.We identified signatures of positive selection on a set of genes involved in reproduction and respiration(e.g., MMD1, NBS1, and HPR), and revealed signatures of molecular convergence on genes involved in self-incompatibility, cell wall modification,DNA repair and stress resistance, which may underlie adaptation to extreme cold, high ultraviolet radiation and hypoxia environments. Incorporating transcriptomic data, we further demonstrated that genes associated with cuticular wax and flavonoid biosynthetic pathways exhibit higher expression levels in leafy bracts, shedding light on the genetic mechanisms of the adaptive “greenhouse” morphology. Our integrative data provide novel insights into convergent evolution at a high-taxonomic level,aiding in a deep understanding of genetic adaptation to complex environments.展开更多
基金supported by the Second Tibetan Plateau Scientific Expedition and Research program (2019QZKK0502)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA20050203)+3 种基金the Key Projects of the Joint Fund of the National Natural Science Foundation of China (U1802232)the Youth Innovation Promotion Association of Chinese Academy of Sciences (2019382)the Yunnan Young & Elite Talents Project (YNWR-QNBJ-2019-033)the Ten Thousand Talents Program of Yunnan Province (202005AB160005)。
文摘Evolutionary convergence is one of the most striking examples of adaptation driven by natural selection.However, genomic evidence for convergent adaptation to extreme environments remains scarce.Here, we assembled reference genomes of two alpine plants, Saussurea obvallata(Asteraceae)and Rheum alexandrae(Polygonaceae), with 37,938 and 61,463 annotated protein-coding genes. By integrating an additional five alpine genomes,we elucidated genomic convergence underlying high-altitude adaptation in alpine plants. Our results detected convergent contractions of diseaseresistance genes in alpine genomes, which might be an energy-saving strategy for surviving in hostile environments with only a few pathogens present.We identified signatures of positive selection on a set of genes involved in reproduction and respiration(e.g., MMD1, NBS1, and HPR), and revealed signatures of molecular convergence on genes involved in self-incompatibility, cell wall modification,DNA repair and stress resistance, which may underlie adaptation to extreme cold, high ultraviolet radiation and hypoxia environments. Incorporating transcriptomic data, we further demonstrated that genes associated with cuticular wax and flavonoid biosynthetic pathways exhibit higher expression levels in leafy bracts, shedding light on the genetic mechanisms of the adaptive “greenhouse” morphology. Our integrative data provide novel insights into convergent evolution at a high-taxonomic level,aiding in a deep understanding of genetic adaptation to complex environments.
