REGULATION OF MEIOSIS IN SPERMATOGENESIS

本研究的长期重点是男性生殖细胞的细胞分裂调控以及细胞周期与精母细胞发育和分化的协调。在果蝇中，分子遗传学分析已经确定boule基因是雄性减数分裂的关键调控基因。在boule突变体的精子发生是正常的减数分裂，但减数分裂I的G2/M转换未能发生，男性不育。分子生物学研究表明，boule属于一个保守的生育因子家族，该家族包括Daz（无精子症中的一个基因）基因，该基因是人类无精子因子（AZF）的候选位点。尽管其脊椎动物同源物在精子发生中的分子作用尚未确定，但已显示Boule对于cdc 25磷酸酶Twine的翻译是必不可少的，这是细胞周期机制的关键组成部分。这一建议的四个具体目标是针对确定的目标，功能域，配对的合作伙伴，和监管机构的Boule蛋白。转基因的方法将被用来分析的功能的Boule，RNA结合蛋白，在缠绕调节。缺失衍生物和定点突变体将被用来分析Boule结构和功能在体外和体内。将进行酵母双杂交筛选以鉴定与Boule蛋白直接相互作用的蛋白质。最后，雄性不育突变体的集合将被筛选用于Boule表达和活性的调节剂。这些研究应提供深入了解配子发生中细胞分裂的基本调控机制，以及与男性不育症的重要遗传原因的调查和治疗具有实质性相关性。

The long term focus of this research is the regulation of cell division in the male germline and the coordination of the cell cycle with spermatocyte development and differentiation. In Drosophila, molecular genetic analyses have identified the boule gene as a key regulatory of meiosis in males. Spermatogenesis in boule mutants is normal up to meiosis, but the G2/M transition of meiosis I fails to occur and males are sterile. Molecular studies have revealed that boule belongs to a conserved family of fertility factors that includes the Daz (Deleted in Azoospermia) gene, a candidate locus for the human Azoospermia Factor (AZF). Whereas the molecular role of its vertebrate homologs in spermatogenesis has not been defined, Boule has been shown to be essential for translation of the cdc25 phosphatase Twine, a key component of the cell cycle machinery. The four specific aims of this proposal are directed at identifying the targets, functional domains, pairing partners, and regulators of the Boule protein. A transgenic approach will be used to analyze the function of Boule, an RNA-binding protein, in Twine regulation. Deletion derivatives and site-directed points mutants will be employed to analyze Boule structure and function both in vitro and in vivo. A yeast two-hybrid screen will be carried out to identify proteins that interact directly with the Boule protein. Lastly, a collection of male-sterile mutants will be screened for regulators for Boule expression and activity. These studies should provide insight into the basic regulatory mechanisms governing cell division in gametogenesis, as well as be of substantial relevance to the investigation and treatment of a significant genetic cause of infertility in men.