DISSERTATION RESEARCH: A Next-generation Sequencing Approach to the Evolution of Male Reproductive Transcriptomes in Seahorses and Pipefishes

相对于大多数由动植物基因组编码的蛋白质，负责生殖过程的蛋白质随着进化时间的推移而迅速变化。更具体地说，在生殖组织中表达的蛋白质编码基因通常显示出快速进化的迹象。这一趋势目前被认为是交配后的性选择的结果，交配后的性选择发生在一种性别的配子争夺另一种性别的配子的时候。在海马和海豚中，雄性在一种类似胎盘的生殖组织中养育发育中的后代，这种生殖组织被称为育儿袋。在这种鱼类家族中，雌性之间争夺这种雄性生殖资源的竞争强度有很大的差异。利用最新的高通量DNA测序技术，研究人员将检验这一预测，即与交配后几乎没有性选择的物种相比，在交配后经历激烈性选择的物种中，雄性生殖蛋白进化得更快。这些数据还将揭示雄性生殖角色和雄性育儿袋特定基因表达模式的进化变化。除了解决中心假设外，这项工作还将为海马和海豚生物学产生前所未有的数量的DNA序列资源。这些信息在许多基本和应用背景下将是有用的，包括开发保护海马及其近亲的遗传学工具，其中许多由于过度捕捞和环境变化而受到威胁。该项目还将通过达拉斯世界水族馆促进与国际科学家的合作和公众宣传。

Relative to the majority of proteins encoded by animal and plant genomes, those responsible for reproductive processes change quickly over evolutionary time. More specifically, protein-coding genes expressed in reproductive tissues routinely show signatures of rapid evolution. This trend is currently thought to arise as a consequence of sexual selection after mating, which occurs when the gametes of one sex compete for access to the gametes of the other sex. In seahorses and pipefishes, males nurture developing offspring in a placenta-like reproductive tissue known as the brood pouch. There is great variation across this family of fishes in the strength of competition among females for access to this male reproductive resource. Using the latest in high-throughput DNA sequencing technologies, the investigators will test the prediction that male reproductive proteins evolve more rapidly in species subject to intense post-mating sexual selection compared to species with little post-mating sexual selection. The data will also shed light on evolutionary changes in patterns of gene expression specific to male reproductive roles and the male's brood pouch. In addition to addressing the central hypothesis, this work will generate an unprecedented number of DNA sequence resources for seahorse and pipefish biology. This information will be useful in many basic and applied contexts, including the development of genetics tools for the conservation of seahorses and their relatives, many of which are imperiled due to over-harvesting and environmental change. The project will also stimulate collaboration with international scientists and public outreach through the the Dallas World Aquarium.