Investigating Conserved Function of Male and Female Developmental Genes in a Model Bivalve

双壳类，如贻贝、牡蛎和蛤，属于第二个最多样化的动物门。它们在沿海生态系统中发挥着关键作用，有助于保持水质，并广泛用于水产养殖。尽管它们的重要性，许多发育过程并没有很好地了解双壳类。一些基因已被确定为与男性和女性的规格和发展;然而，他们的确切作用还不清楚。该项目的目标是描述这些基因在双壳类发育中的特征，并确定它们在区分雄性和雌性生殖器官的过程中的作用。我们的方法包括记录不同组织中的基因表达水平，并通过实验降低其表达水平以观察发育中的变化。该项目将提供关键的洞察男性和女性的生殖器官的规格和分化的过程。我们的项目还将有助于增加那些在课堂外有义务的学生的机会，这些义务阻碍了他们攻读STEM学位的能力。研究表明，在线实验室课程，特别是那些包括“自己动手”（DIY）套件和手册的课程，可以与现场实验室一样有效，并为难以投入时间参加现场实验室课程的学生减少障碍。该项目旨在创建一个完全在线的海洋生物学和生理学DIY实验室，作为增加STEM实验室可访问性和扩大参与的典范。 虽然已经提出了一些假设模型的机制，男性和女性特定的性腺发育的软体动物，有很少的实验测试的基因功能在这个过程中。利用转录组学，我们已经确定了几个假定的性腺发育基因的双壳类，包括软体动物特有的DMRT基因：DMRT 1 L。我们提出的项目的主要目标是在一个模型，雌雄异株，成年双壳类，蓝贻贝M的性腺发育基因的作用的特点。（1）利用RT-qPCR和原位杂交技术，研究雄性和雌性性腺发育相关基因的时间特异性和组织特异性表达模式。(2)使用RNAi（SoxH、DMRT 1 L、FoxL 2、β-连环蛋白）敲低关键性腺发育基因后，评价雄性和雌性性腺发育的变化。这些基因已经在双壳贝类中进行了研究;然而，这项工作依赖于雄性和雌性之间基因表达的相关性以及从远亲物种中获得的知识。这项工作将验证这些假定的雄性和雌性发育基因的作用，并将使我们能够开发一个基于转录本的双壳类性腺发育途径。这项拟议的工作将是变革性的，以了解男性和女性之间的关系，发展途径之间的关系，在远亲后生动物物种，以及他们是如何演变的。这个奖项反映了NSF的法定使命，并已被认为是值得的支持，通过评估使用基金会的智力价值和更广泛的影响审查标准。

Bivalves, such as mussels, oysters, and clams, belong to the second most diverse animal phylum. They play a critical role in coastal ecosystems, help maintain water quality, and are widely used in aquaculture. Despite their importance, many developmental processes are not well understood in bivalves. Several genes have been identified to be correlated with male and female specification and development; however, their exact role is not yet known. The goal of this project is to characterize these genes in bivalve development and identify their roles in the process of differentiating male and female reproductive organs. Our methods involve documenting levels of in gene expression in different tissues and experimentally lowering their expression level to observe changes in development. This project will provide critical insight into the process of male and female specification and differentiation of reproductive organs. Our project will also help to increase opportunities for students that have obligations outside of the classroom that hinder their ability to pursue a STEM degrees. Research shows that online laboratory courses, especially those that include “Do it yourself” (DIY) kits and manuals, can be as effective as in person labs and decrease barriers for students that have difficulty devoting time to in person laboratory courses. This project aims to create a completely online DIY laboratory in marine biology and physiology that will act as a model for increasing accessibility to STEM labs and broaden participation. Although some hypothetical models have been proposed for mechanisms underlying male and female specific gonadal development in mollusks, there have been very few experimental tests of gene function in this process. Using phylotranscriptomics, we have identified several putative gonadal development genes in bivalves, including a mollusk specific DMRT gene: DMRT1L. The primary objective of our proposed project is to characterize the role of putative gonadal development genes in a model, gonochoristic, adult bivalve, the blue mussel M. edulis through two specific aims: (1) Determine the temporal and tissue-specific expression patterns of male and female gonadal development genes using RT-qPCR and in situ hybridization in relation to gametogenesis. (2) Evaluate changes in gonadal development in males and females following knockdown of key gonadal development genes using RNAi (SoxH, DMRT1L, FoxL2, β-catenin). These genes have been studied in bivalves; however, this work has relied on correlations in gene expression between males and females and knowledge gained from distantly related species. The proposed work will verify the roles of these putative male and female developmental genes and will enable us to develop a transcript-based gonadal development pathway for bivalves. This proposed work will be transformative to understanding the relationships between male and female development pathways across distantly related metazoan species and how they evolved.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.