Collaborative Proposal: Testing mechanisms and consequences of W chromosome turnover in a dynamic plant system

这项研究将检验基因和染色体的进化理论，这些理论决定了个体是男性还是女性。该项目将确定导致栽培草莓野生祖先性别决定基因染色体位置变化的过程。这项工作将推进我们对这些变化如何影响基因功能和整个植物生长和繁殖的认识。了解基因如何排列在染色体上将扩大我们对不同基因位置对花和果实发育影响的认识，并将为确保粮食安全的农业实践提供信息。教育和推广活动将把本研究所得的知识带给大众，并有助于初高中学生的课程发展。性别的遗传决定在真核生物中广泛存在，进化动力学可以超越广泛的分类界限。决定性别的染色体对或性别决定基因位置的变化都可能是表型二态性、适应性变异和物种形成的重要驱动因素。该研究将测试四种主要的假设机制，以及W染色体更替的表型后果。这项工作将利用八倍体野生草莓（Fragaria），在那里已经观察到基于易位的更替，从而能够测试每种更替机制特征的基因组指纹（连锁不平衡和功能多态性的变化）的预测模式。这项工作将结合高通量测序、分子进化分析、遗传连锁作图、转录组学和表型评估。该研究将为染色体进化的关键动态提供见解，并阐明基因组重组机制，该机制也是影响复杂表型，适应和物种形成的其他超基因进化的基础。这项工作将通过扩大对栽培草莓重要野生近缘染色体重排对生态耐受性影响的认识，为社会做出贡献。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This research will test theories of the evolution of the genes and chromosomes that determine whether individuals are male or female. The project will identify processes that lead to changes in the chromosomal location of sex-determining genes in wild ancestors of the cultivated strawberry. The work will advance our knowledge of how these changes affect gene function and whole-plant growth and reproduction. Understanding how genes are arranged on chromosomes will expanding our knowledge of the effects of varied gene location on flower and fruit development, and will inform agricultural practices that ensure food security. Educational and outreach activities will bring knowledge gained by this research to the general public, and contribute to curriculum development for middle school and high school students.Genetic determination of sex is widespread across eukaryotes and the evolutionary dynamics can transcend wide taxonomic boundaries. Changes in either the chromosome pair that determines sex or the location of the sex-determining genes can be an important driver of phenotypic dimorphism, adaptive variation, and speciation. The research will test four leading hypothesized mechanisms for, and phenotypic consequences of, turnover in the W chromosome. The work will leverage the octoploid wild strawberry (Fragaria) where translocation-based turnover has been observed, enabling tests of predicted patterns of genomic fingerprints (changes in linkage disequilibrium and function polymorphisms) characteristic of each turnover mechanism. The work will use a combination of high-throughput sequencing, molecular evolutionary analysis, genetic linkage mapping, transcriptomics, and phenotypic assessment. The research will provide insight into a key dynamic of chromosomal evolution and shed light on a genomic restructuring mechanism that also underlies the evolution of other supergenes affecting complex phenotypes, adaptation, and speciation. The work will contribute to society by expanding knowledge of the effects of chromosomal rearrangement on ecological tolerances in important wild relatives of the cultivated strawberry.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.