Exploring the Role of Altered Hybrid Recombination in Contributing to Speciation

探索改变的杂交重组在促进物种形成中的作用

• 批准号: 8455657
• 负责人: Laurie Sherie Stevison
• 金额: $ 4.92万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-02-01 至 2015-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8455657
• 关键词: Accounting; Address; Alleles; Area; Automobile Driving; Biodiversity; Biological; Biology; Categories; Chromosome Mapping; Chromosome inversion; Consensus; Data; Data Analyses; Disease; Drosophila genus; Educational workshop; Event; Gene Exchanges; Genes; Genetic; Genetic Recombination; Genome; Genomic Segment; Genomics; Goals; Human; Hybrids; Individual; Learning; Link; Maps; Methods; Metric; Nucleotides; Organism; Pattern; Play; Process; Public Health; Publications; Relative (related person); Reproduction; Research; Research Personnel; Role; Sample Size; Source; Structure; Surveys; System; Taxon; Testing; Variant; Work; base; biological systems; computerized tools; density; experience; genetic element; genetic variant; genome sequencing; insight; literature survey; novel; prevent; programs; public health relevance; reproductive; skills; statistics; structural genomics; systems research; trend

DESCRIPTION (provided by applicant): A major question in evolutionary biology, determining the genetic source of biodiversity, is best answered by examining species at the interface of speciation - closely related species that are known to hybridize. Recent genetic advances have highlighted the pervasiveness of hybridization in these species. Further, dense marker analysis shows that genetic exchange between species is not uniformly distributed across the genome. This proposal aims to understand which factors contribute to this regional variation in gene flow across the genetic landscape. Much work in speciation has been focused on understanding those factors that produce barriers to reproduction, focusing particularly on regions where divergence between species is high. These regions may correspond to speciation genes that are selected against in different genetic backgrounds, or structural variants such as chromosomal inversions that limit interspecies gene exchange. Beyond inversions, no structural features have been identified which commonly differentiate recently diverged species. Our research proposes to survey many hybridizing taxa and understand what contributes to variation in genetic exchange between species. Specifically, we propose to computationally predict recombination rate differences in hybrids relative to within species linkage maps. We will then determine if changes in hybrid recombination rates (as compared to within-species recombination rates) are associated with changes in between species nucleotide divergence. We predict that this correlation will highlight regions of the genome important in speciation. These changes could be due to genetic variants that act like inversions to prevent hybrid alleles from being incorporated into the genome. Therefore, we plan to dissect these regions in our survey of taxa and examine if these feature any common genetic elements that distinguish recently diverged species could contribute to the pattern. Recent research in humans has revealed extensive evidence of genomic structural variation within and between individuals. Some of these variants have been connected to disease; however, our overall understanding of the role of these variants in contributing to the structure of our genome is still limited. Our stuy aims to understand if these variants play a role in facilitating speciation by disrupting genetic exchange, which has also been linked to disease. By making use of existing data in a variety of biological systems, the results of our research have the potential to make predictions about which regions of the genome are likely to be important in speciation in other research systems.

描述（由申请人提供）：进化生物学中的一个主要问题，即确定生物多样性的遗传来源，最好的回答是通过检查物种形成界面的物种——已知会杂交的密切相关的物种。最近的遗传学进展凸显了这些物种中杂交的普遍性。此外，密集标记分析表明，物种之间的遗传交换在整个基因组中分布并不均匀。该提案旨在了解哪些因素导致了整个遗传景观中基因流的区域差异。 物种形成方面的许多工作都集中在了解那些对繁殖产生障碍的因素，特别是物种间差异较大的地区。这些区域可能对应于在不同遗传背景中选择的物种形成基因，或结构变异，例如限制种间基因交换的染色体倒位。除了倒置之外，还没有发现通常可以区分最近分化的物种的结构特征。 我们的研究计划调查许多杂交类群，并了解是什么导致了物种间遗传交换的变异。具体来说，我们建议通过计算预测杂种相对于物种内连锁图的重组率差异。然后我们将确定杂种重组率的变化（与种内重组率相比）是否与物种间核苷酸分歧的变化相关。我们预测这种相关性将突出基因组中对物种形成重要的区域。这些变化可能是由于遗传变异造成的，这些变异的作用类似于倒位，以阻止杂交等位基因被纳入基因组中。因此，我们计划在分类群调查中剖析这些区域，并检查这些区域是否有任何区分最近分化物种的共同遗传元件可能有助于这种模式。 最近对人类的研究揭示了个体内部和个体之间基因组结构变异的广泛证据。其中一些变异与疾病有关；另一些则与疾病有关。然而，我们对这些变异对基因组结构的作用的总体了解仍然有限。我们的研究旨在了解这些变异是否通过破坏基因交换来促进物种形成，而基因交换也与疾病有关。通过利用各种生物系统中的现有数据，我们的研究结果有可能预测基因组的哪些区域可能对其他研究系统的物种形成很重要。