The Genomic Basis and Molecular Mechanisms of Speciation

物种形成的基因组基础和分子机制

• 批准号: 10706528
• 负责人: Yasir Ahmed
• 金额: $ 37.5万
• 依托单位: SYRACUSE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-19 至 2027-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10706528
• 关键词: Affect; Biological Models; Biology; Cell physiology; Complex; Coupled; Creativeness; Data; Drosophila genus; F Factor; Functional disorder; Genes; Genetic; Genetic Drift; Genetic Techniques; Genetic Variation; Genome; Genomics; Goals; Hybrids; Male Sterility; Male Sterilizations; Molecular; Molecular Genetics; Mutation; Partner in relationship; Pathway interactions; Population; Process; Proteomics; Research; Sterility; Subgroup; X Chromosome; Y Chromosome; human disease; improved; innovation; male fertility; member; reproductive; tool; trait; transcriptomics

PROJECT SUMMARY One of the fundamental problems in evolutionary biology is to understand the molecular genetic basis of speciation. Recent advances in speciation research have improved our understanding of interspecific divergence, but we still lack a comprehensive understanding of the molecular processes that diverge among incipient species. In the handful of cases where the genetic mechanisms of reproductive isolation have been elucidated, these invariably tackle late-evolving and/or hybrid dysfunction. This means that we still lack a general understanding of the molecular processes that govern pre-zygotic reproductive barriers, even though these are often important early in the speciation process. My lab will tackle this problem by identifying the molecular genetic basis of pre-zygotic and post-zygotic re- productive isolation between members of the Drosophila virilis species sub-group. This species group provides an especially unique opportunity to dissect the genetic and molecular mechanisms of pre-zygotic barriers, as members of this group are prone to evolve these types of barriers quickly between species and even among populations of the same species. Our overall approach integrates several strategies to answer the following questions: What are the genetic mechanisms that cause reproductive isolation between species? Which molec- ular and cellular processes are affected by divergence of these genetic mechanisms? What are the evolutionary forces that drive divergence of the relevant genes between species? What is the landscape of natural genetic variation within and between species that facilitates evolutionary divergence of these genes? The first project within this proposal will focus on post-mating pre-zygotic barriers (i.e., gametic incompatibil- ities). I have previously shown that gametic incompatibilities are rampant in the D. virilis sub-group, and that the genetic basis is moderately complex but highly tractable using a combination of molecular genetics techniques coupled with transcriptomic and proteomic analyses of reproductive traits. The second project will tackle the mechanisms of hybrid male sterility that are caused by incompatibilities between the Y and X chromosomes. The Drosophila Y chromosome carries several male fertility factors, but it has seldom been directly implicated in interspecific hybrid sterility between closely related species. Our preliminary data show that the Y chromosome is necessary and sufficient to cause sterility in hybrids. The research in this proposal will be innovative because we will deploy cutting edge tools in creative ways that will allow us to dissect complex genetic mechanisms in a newly established model system.

项目概要 进化生物学的基本问题之一是了解生物的分子遗传基础 物种形成研究的最新进展提高了我们对种间差异的理解， 但我们仍然缺乏对早期物种之间差异的分子过程的全面了解。 在生殖隔离的遗传机制已被阐明的少数案例中，这些 总是要解决晚期进化和/或混合功能障碍，这意味着我们仍然缺乏总体理解。 控制合子前生殖障碍的分子过程，尽管这些通常很重要 在物种形成过程的早期。 我的实验室将通过确定合子前和合子后重组的分子遗传基础来解决这个问题。 该物种组提供了果蝇物种亚群成员之间的有效隔离。 这是一个特别独特的机会来剖析合子前障碍的遗传和分子机制，例如 该群体的成员很容易在物种之间甚至物种之间迅速形成这些类型的障碍 我们的总体方法整合了多种策略来回答以下问题。 问题：导致物种间生殖隔离的遗传机制是什么？ 细胞和细胞过程受到这些遗传机制差异的影响？ 推动物种间相关基因分化的力量是什么？ 物种内部和物种之间的变异促进了这些基因的进化分歧？ 该提案中的第一个项目将重点关注交配后合子前障碍（即配子不相容性） 我之前已经表明，配子不亲和性在 D. virilis 亚群中非常普遍，并且 遗传基础相当复杂，但结合分子遗传学技术非常容易处理 结合生殖特征的转录组学和蛋白质组学分析。 由 Y 和 X 染色体不相容引起的杂种雄性不育机制。 果蝇 Y 染色体携带多种雄性生育因子，但很少与雄性生育力直接相关。 我们的初步数据表明，Y 染色体在密切相关的物种之间存在种间杂交不育性。 对于导致杂种不育是必要且充分的。 本提案中的研究将具有创新性，因为我们将以创造性的方式部署尖端工具， 将使我们能够在新建立的模型系统中剖析复杂的遗传机制。