FUNCTIONAL ROLE OF MDAZ IN INFERTILITY

描述：（改编自申请人的描述）：约10% 全世界的夫妇都受到生育率下降的影响， 这些病例中约有一半是由于缺乏精子生产造成的。 男性（无精子症）。无精子症患者的细胞学分析 在很大一部分病例中发现了Y染色体的缺失 这意味着表型的遗传成分。该区域被提议 含有无精子因子（AZF）。随后对这一地区的分析 确定了三个不同的基因作为AZF候选者，其中一个被称为 无精子症（DAZ）。有趣的是，DAZ的小鼠同源物（mDAZ） 是常染色体的小鼠中mDAZ基因的纯合破坏导致 没有超过精原细胞阶段的生殖细胞，表明 DAZ/mDAZ在精子发生中意义DAZ基因编码一种生殖细胞- 限制性细胞质RNA结合蛋白。虽然DAZ的功能是 未知，它似乎调节靶mRNA的细胞质代谢 在精子发生中必不可少。尽管DAZ基因已经被发现， 研究其基因产物的功能以及它如何有助于 无精子症是有限的，没有识别的同源mRNA底物， 它所约束和调节的。我们最近设计了一种新的策略， 鉴定与RNA结合蛋白结合天然同源mRNA。这种技术 能够快速鉴定和克隆特异性细胞mRNA， RNA结合蛋白这项建议的目的是确定自然的 与mDAZ蛋白（AIM 1）结合并表征 mDAZ调节这些靶基因的机制以及它如何有助于 精子发生（AIM 2）。这将提供对函数的有价值的深入了解 DAZ在无精子症发病机制中的作用，最终导致了 受影响个体的治疗策略。了解这些 在精子生产中正常发挥作用的蛋白质也将提供新的 男性避孕策略。

DESCRIPTION: (Adapted from applicant's description): Approximately 10% of couples world-wide are affected by reduced rates of fertility and approximately half of these cases result from the absence of sperm production (azoospermia) in males. Cytological analysis of patients with azoospermia identified a deletion on the Y chromosome in a significant proportion of cases implying a genetic component to the phenotype. This region was proposed to contain an Azoospermia Factor (AZF). Subsequent analysis of this region identified three distinct genes as AZF candidates one of which was termed Deleted in Azoospermia (DAZ). Interestingly, the mouse homologue of DAZ (mDAZ) is autosomal. Homozygous disruption of the mDAZ gene in mice results in the absence of germ cells beyond the spermatogonial stage demonstrating the significance of DAZ/mDAZ in spermatogenesis. The DAZ gene encodes a germ cell- restricted cytoplasmic RNA-binding protein. Although the function of DAZ is unknown, it appears to regulate the cytoplasmic metabolism of a target mRNA(s) essential in spermatogenesis. Despite the identification of the DAZ gene, progress into the function of its gene product and how it contributes to azoospermia is limited without identification of the cognate mRNA substrate that it binds to and regulates. We have recently devised a novel strategy to identify natural cognate mRNA bound by RNA-binding proteins. This technique enables rapid identification and cloning of specific cellular mRNA bound by an RNA-binding protein. The objective of this proposal is to identify the natural mRNA(s) which are bound by the mDAZ protein (AIM 1) and characterize the mechanism by which mDAZ regulates these target genes and how it contributes to spermatogenesis (AIM 2). This will provide valuable insight into the function of DAZ in the pathogenesis of azoospermia, eventually leading to the design of therapeutic strategies in affected individuals. Understanding how these proteins normally function in sperm production will also provide novel strategies in male contraception.