Apoptotic dysregulation in male infertility

项目摘要/摘要 在不同物种之间，性发育和生育能力取决于细胞死亡事件。正在开发中 在哺乳动物的卵巢和睾丸中，生殖细胞(精子和卵子的前体)的大量死亡发生在 胎儿磨损事件，被认为是为了防止过度增殖和选择最高质量的细胞。细胞死亡是 在形成雌性生殖道的结构的胚胎退化过程中，也可以在雄性身上观察到，以及 脑下垂体的形态发生，它调节性腺性激素的产生。令人惊讶的是，抑制 导致小鼠雄性不育，但尚不清楚为什么会发生这种情况，也不知道细胞如何死亡 在整个男性性发育过程中都受到监管。我这项研究的目的是要了解 沿着下丘脑-垂体-性腺轴(HPG)的细胞凋亡贯穿整个男性性发育过程，以及为什么 细胞凋亡的破坏会导致不孕。具体地说，这项建议旨在描绘正常人群中细胞凋亡的敏感性。 睾丸生殖细胞，并寻找不育男性生殖组织中细胞凋亡失调的证据。在……里面 目的1.生殖细胞在发育和分化的不同阶段的易凋亡性 使用功能细胞死亡预测分析和睾丸照射诱导生殖细胞死亡。在……里面 目的通过对胚胎的分析，探讨细胞凋亡在男性性别分化中的要求。 生殖道发育和成年HPG轴信号在细胞凋亡不足遗传模型中的作用。 睾丸生殖细胞移植将被用来确定生殖系与体细胞的贡献。 细胞凋亡失调对男性不育的影响。这些发现将支持确定有针对性的治疗 影响发育中儿童的性发育障碍或细胞毒性暴露，导致贫困 成年后的生殖结果。 拟议研究金的培训计划将进一步发展分子和 发展生物学方法，并解决在概念和技术上缺乏经验的其他学科 生殖科学，包括内分泌学和流行病学。它还将提供机会，从 斑马鱼以小鼠作为疾病和发育的模型。这将通过持续教育来实现。 生物统计学，与共同赞助者一起培训，并利用跨学科科学咨询委员会监督 实验设计和数据分析。年内还将进行负责任的研究培训。 1.哈佛大学公共卫生学院，致力于多方面研究生殖健康和 不孕症，将大力支持这项研究和培训计划的成像和分析设施以及 监督该领域的老牌教员。Kristopher Sarosiek的实验室，擅长于功能 对细胞凋亡的分析，将使一项独特而严谨的研究计划得以发展，将性别 细胞死亡的发展和分子生物学，以揭示导致男性不育的机制。

Project Summary/Abstract Across species, sexual development and fertility are dependent on cell death events. In developing ovaries and testes in mammals, massive death of germ cells (precursors of sperm and eggs) occurs during a fetal attrition event that is presumed to prevent overproliferation and select for highest quality cells. Cell death is also observed in males during embryonic regression of structures that form the female reproductive tract, and morphogenesis of the pituitary gland, which regulates gonadal sex hormone production. Surprisingly, inhibition of apoptosis results in male-specific infertility in mice, but it is not understood why this occurs or how cell death is regulated throughout male sexual development. The goal of my research is to understand regulation of apoptosis along the hypothalamic-pituitary-gonadal (HPG) axis throughout male sexual development, and why disruption of apoptosis causes infertility. Specifically, this proposal aims to map apoptotic sensitivity in normal testicular germ cells, and to find evidence of apoptotic misregulation in reproductive tissues in infertile males. In Aim 1, the apoptotic vulnerability of germ cells at different stages of development and differentiation will be determined using functional cell death-predictive assays and testicular irradiation to induce germ cell death. In Aim 2, the requirement of apoptosis in male sex differentiation will be investigated by analyzing embryonic reproductive tract development and adult HPG axis signaling in genetic models of apoptosis insufficiency. Testicular germ cell transplantation will be used to establish contribution of germline vs. somatic testicular cell apoptosis dysregulation to male infertility. These findings will support identification of targeted treatments for disorders of sexual development or cytotoxic exposures affecting developing children, which lead to poor reproductive outcomes as adults. The training plan for the proposed fellowship will further develop expertise in molecular and developmental biology approaches, and address conceptual and technical inexperience in other disciplines of reproductive science, including endocrinology and epidemiology. It will also provide the opportunity to move from zebrafish to mice as a model of disease and development. This will be achieved by continuing education in biostatistics, training with a co-sponsor, and utilizing an interdisciplinary scientific advisory committee to oversee experimental design and data analysis. Responsible conduct of research training will also be undertaken in Year 1. The Harvard School of Public Health, which is committed to the multi-faceted study of reproductive health and infertility, will strongly support this research and training plan with imaging and analytical facilities as well as oversight of established faculty in the field. The laboratory of Kristopher Sarosiek, which excels at functional assays of apoptosis, will enable development of a unique and rigorous research program that bridges sexual development and the molecular biology of cell death in order to uncover mechanisms driving male infertility.