The evolution of gametic compatibility within species and reproductive isolation across species

物种通常由个体之间能否成功交配来定义。如果个体可以，他们通常被认为是同一物种的一部分，如果他们不能，他们被认为是不同物种的成员。目前尚不确定的是生殖不亲和性是如何起源和演变的。该项目旨在调查决定生殖亲和性的蛋白质的变异是如何产生的，以及这种变异在海胆物种之间建立受精障碍方面的后果。更广泛的影响包括为高中教师设计和实施一个研讨会，以开发使用海胆受精作为模型来理解生殖隔离和物种形成的模块；这是佛罗里达州标准中的一个关键学习概念。拟议的工作将调查物种内的性别冲突如何导致配子识别蛋白质的种内变异，以及强化选择如何对这种蛋白质变异产生作用，从而影响四种海胆物种的生殖隔离进化；两种海胆共同出现在北美西海岸，两种海胆分布在极地。这些方法包括：(1)强势种生殖蛋白的基因组和基因表达；(2)种内和种间杂交，以确定从以前的工作中已知的和通过表达分析新鉴定的蛋白质变异如何影响种内和种间的繁殖亲和性；以及(3)西海岸和环极地物种之间亲和性和蛋白质变异的变化的证据。这项工作代表了理解配子识别蛋白和生殖隔离的表型和分子进化的生态背景。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Species are generally defined by whether individuals can mate successfully with each other. If individuals can, they are generally considered part of the same species, if they cannot they are considered to be members of different species. What remains uncertain is how reproductive incompatibilities originate and evolve. This project aims to investigate how variation in the proteins that determine reproductive compatibility is generated, and the consequences of this variation in establishing barriers to fertilization among species of sea urchins. The broader impacts include the design and implementation of a workshop for high school teachers to develop modules for using sea urchin fertilization as a model to understand reproductive isolation and speciation; a key learning concept in the Florida State Standards.The proposed work will investigate how within species sexual conflict might generate intraspecific variation in gamete recognition proteins and how reinforcement selection might act on this protein variation to influence the evolution of reproductive isolation among four strongylocentrotid sea urchin species; two that co-occur along the West Coast of North America and two that have a circumpolar distribution. The methods include generation of the (1) genomes and gene expression of reproductive proteins in strongylocentrotid species; (2) crosses within and among species to determine how the protein variants known from prior work, and newly identified by the expression assays, influence within and across species reproductive compatibility and (3) evidence for shifts in compatibility and protein variation in and out of sympatry between the West Coast and circumpolar species. This work represents an ecological context for understanding the phenotypic and molecular evolution of gamete recognition proteins and reproductive isolation.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.