{"title":"同源交叉具有远端偏向性,是拟南芥第一代新全多倍体基因组不稳定的基础。","authors":"Candida Nibau, Aled Evans, Holly King, Dylan Wyn Phillips, Andrew Lloyd","doi":"10.1111/nph.20095","DOIUrl":null,"url":null,"abstract":"<p><p>First-generation polyploids often suffer from more meiotic errors and lower fertility than established wild polyploid populations. One such example is the allopolyploid model species Arabidopsis suecica which originated c. 16 000 generations ago. We present here a comparison of meiosis and its outcomes in naturally evolved and first-generation 'synthetic' A. suecica using a combination of cytological and genomic approaches. We show that while meiosis in natural lines is largely diploid-like, synthetic lines have high levels of meiotic errors including incomplete synapsis and nonhomologous crossover formation. Whole-genome re-sequencing of progeny revealed 20-fold higher levels of homoeologous exchange and eightfold higher aneuploidy originating from synthetic parents. Homoeologous exchanges showed a strong distal bias and occurred predominantly in genes, regularly generating novel protein variants. We also observed that homoeologous exchanges can generate megabase scale INDELs when occurring in regions of inverted synteny. Finally, we observed evidence of sex-specific differences in adaptation to polyploidy with higher success in reciprocal crosses to natural lines when synthetic plants were used as the female parent. Our results directly link cytological phenotypes in A. suecica with their genomic outcomes, demonstrating that homoeologous crossovers underlie genomic instability in neo-allopolyploids and are more distally biased than homologous crossovers.</p>","PeriodicalId":48887,"journal":{"name":"New Phytologist","volume":null,"pages":null},"PeriodicalIF":9.4000,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Homoeologous crossovers are distally biased and underlie genomic instability in first-generation neo-allopolyploid Arabidopsis suecica.\",\"authors\":\"Candida Nibau, Aled Evans, Holly King, Dylan Wyn Phillips, Andrew Lloyd\",\"doi\":\"10.1111/nph.20095\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>First-generation polyploids often suffer from more meiotic errors and lower fertility than established wild polyploid populations. One such example is the allopolyploid model species Arabidopsis suecica which originated c. 16 000 generations ago. We present here a comparison of meiosis and its outcomes in naturally evolved and first-generation 'synthetic' A. suecica using a combination of cytological and genomic approaches. We show that while meiosis in natural lines is largely diploid-like, synthetic lines have high levels of meiotic errors including incomplete synapsis and nonhomologous crossover formation. Whole-genome re-sequencing of progeny revealed 20-fold higher levels of homoeologous exchange and eightfold higher aneuploidy originating from synthetic parents. Homoeologous exchanges showed a strong distal bias and occurred predominantly in genes, regularly generating novel protein variants. We also observed that homoeologous exchanges can generate megabase scale INDELs when occurring in regions of inverted synteny. Finally, we observed evidence of sex-specific differences in adaptation to polyploidy with higher success in reciprocal crosses to natural lines when synthetic plants were used as the female parent. Our results directly link cytological phenotypes in A. suecica with their genomic outcomes, demonstrating that homoeologous crossovers underlie genomic instability in neo-allopolyploids and are more distally biased than homologous crossovers.</p>\",\"PeriodicalId\":48887,\"journal\":{\"name\":\"New Phytologist\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":9.4000,\"publicationDate\":\"2024-09-06\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"New Phytologist\",\"FirstCategoryId\":\"99\",\"ListUrlMain\":\"https://doi.org/10.1111/nph.20095\",\"RegionNum\":1,\"RegionCategory\":\"生物学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"Agricultural and Biological Sciences\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"New Phytologist","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1111/nph.20095","RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"Agricultural and Biological Sciences","Score":null,"Total":0}
Homoeologous crossovers are distally biased and underlie genomic instability in first-generation neo-allopolyploid Arabidopsis suecica.
First-generation polyploids often suffer from more meiotic errors and lower fertility than established wild polyploid populations. One such example is the allopolyploid model species Arabidopsis suecica which originated c. 16 000 generations ago. We present here a comparison of meiosis and its outcomes in naturally evolved and first-generation 'synthetic' A. suecica using a combination of cytological and genomic approaches. We show that while meiosis in natural lines is largely diploid-like, synthetic lines have high levels of meiotic errors including incomplete synapsis and nonhomologous crossover formation. Whole-genome re-sequencing of progeny revealed 20-fold higher levels of homoeologous exchange and eightfold higher aneuploidy originating from synthetic parents. Homoeologous exchanges showed a strong distal bias and occurred predominantly in genes, regularly generating novel protein variants. We also observed that homoeologous exchanges can generate megabase scale INDELs when occurring in regions of inverted synteny. Finally, we observed evidence of sex-specific differences in adaptation to polyploidy with higher success in reciprocal crosses to natural lines when synthetic plants were used as the female parent. Our results directly link cytological phenotypes in A. suecica with their genomic outcomes, demonstrating that homoeologous crossovers underlie genomic instability in neo-allopolyploids and are more distally biased than homologous crossovers.
期刊介绍:
New Phytologist is a leading publication that showcases exceptional and groundbreaking research in plant science and its practical applications. With a focus on five distinct sections - Physiology & Development, Environment, Interaction, Evolution, and Transformative Plant Biotechnology - the journal covers a wide array of topics ranging from cellular processes to the impact of global environmental changes. We encourage the use of interdisciplinary approaches, and our content is structured to reflect this. Our journal acknowledges the diverse techniques employed in plant science, including molecular and cell biology, functional genomics, modeling, and system-based approaches, across various subfields.