Role of nuclear receptors in origin and differentiation of spermatozoa

描述（由申请人提供）：精子发生是一个复杂的发育过程，未分化的精原细胞分化为成熟的精子，然后能够使卵母细胞受精。在哺乳动物中，这个过程涉及数百个基因，这些基因在精子分化的特定阶段在生精组织中受到差异调节。通过比较基因表达和功能研究，利用具有保守发育过程的简单动物模型，可以显著了解控制精子发生的关键调控基因。我提出的研究将表征基因表达、蛋白-蛋白相互作用和基因沉默，并结合转录谱分析，以阐明三种孤儿核受体（睾丸孤儿受体和生殖细胞核因子）在精子发育和分化中的整体作用，利用新兴的模型Nematostella vectensis（小海葵）。这些受体中的每一种都在哺乳动物睾丸中精子分化的不同阶段高度表达；因此，所提出的研究结果将描述与人类男性生育能力相关的核受体功能的新作用。拟议的研究通过确定人类生殖健康的遗传机制，支持了尤尼斯肯尼迪施莱佛国家儿童健康和人类发展研究所生殖科学分部的使命。此外，这三种转录因子与核受体超家族中的其他基因一样，由于在各种胚胎癌细胞系中的表达，在胚胎发生中具有多效性作用，包括在神经和心血管系统的发育以及癌症中发挥作用。我将利用已经为线虫菌开发的实验易感性和工具来探索这些受体在胚胎发育和异常细胞调节中的其他作用。确定和描述在人类生育中起根本作用的基因是推进人类生殖诊断和治疗的关键一步。利用形态学简单和实验易于处理的动物模型来测试特定的分子过程可以在理解机制方面取得快速进展。Nematostella是一个新兴的模型系统，将研究三个在男性精子发生中高度表达和功能重要的基因的作用，以了解它们在成熟精子从未分化干细胞分化中的作用。

DESCRIPTION (provided by applicant): Spermatogenesis is a complex developmental process where undifferentiated spermatogonia are differentiated into mature spermatozoa that are then able to fertilize oocytes. In mammals, this process involves hundreds of genes that are differentially regulated in spermatogenic tissue at particular stages of sperm differentiation. Identifying critical, regulatory genes controlling spermatogenesis can be significantly Informed through comparative gene expression and functional studies utilizing simpler animal models that have conserved developmental processes. My proposed research will characterize gene expression, protein-protein interactions, and gene silencing coupled with transcriptional profiling to elucidate the integral role of three orphan nuclear receptors (testicular orphan receptors and germ cell nuclear factor) in sperm development and differentiation utilizing the emerging model Nematostella vectensis (starlet sea anemone). Each of these receptors has been shown to be highly expressed in mammal testes at discrete stages of sperm differentiation; thus results from the proposed research will characterize novel roles for nuclear receptor function related to human male fertility. The proposed research supports the mission of the Reproductive Sciences Branch of The Eunice Kennedy Shriver National Institute of Child Health and Human Development by identifying genetic mechanisms that underlie reproductive health in humans. In addition, these three transcription factors, like other genes in the nuclear receptor superfamily, have pleiotropic roles in embryogenesis including roles in development of the nervous and cardiovascular system and in cancer due to expression in various embryonal carcinoma cell lines. I will take advantage of the experimental tractability and tools already developed for Nematostella to explore the additional roles of these receptors in embryo development and abnormal cell regulation. Relevance to Public Health Identifying and characterizing genes that play a fundamental role in human fertility is a critical step towards advancing diagnosis and treatment in human reproduction. Utilizing morphologically simple and experimentally tractable animal models to test specific molecular processes can result in rapid progress in understanding mechanisms. Nematostella, an emerging model system, will be used to study the role of three genes highly expressed and functionally important in male spermatogenesis to understand their role in differentiation of mature sperm from undifferentiated stem cells.