ROLE OF PROTEIN-TYROSINE KINASES IN SPERMATOGENESIS

这项研究的长期目标是达到一个 了解控制哺乳动物精子的分子机制 发展 这些研究将确定人类疾病的潜在原因。 不孕症，并可能提出治疗这一问题的方法。 新方法 男性避孕是另一个可能的好处， 区 生殖细胞和支持细胞在子宫内膜中的相互作用 曲细精管对精子发育至关重要， 到目前为止，我们已经了解到这些相互作用是如何在一个 分子水平。 在发育中表达的蛋白酪氨酸激酶 精母细胞和精子细胞是本申请的焦点。 成员 通过它们在信号转导中的作用， 被认为是发展中的关键调节分子， 多种动物组织和蛋白酪氨酸激酶在雄性中表达 因此，生殖细胞是作为调节因子的强有力的候选者。 精子发生 通过使用基于同源性的cDNA克隆策略， 蛋白酪氨酸激酶家族的新成员，命名为 “PTK-T126”，被鉴定为似乎在发育中表达。 精母细胞和/或精子细胞。 本文中描述的具体研究 应用程序旨在确定导致 PTK-T126的生产并表征其细胞分布， 结构和生化特性。 具体而言：结构特征 PTK-T126的氨基酸序列分析将确定PTK-T126的氨基酸序列。 序列，其将从cDNA的核苷酸序列推导出 克隆;睾丸特异性转录本与 编码PTK-T126和相关的更广泛表达的转录物， 将通过检查cDNA序列并通过引物 延伸分析;将产生针对PTK-T126的抗体试剂， 将用于检测睾丸细胞中的蛋白质， 免疫纯化蛋白质以测定酪氨酸激酶活性; 以及在细胞周期中调节PTK-T126表达的可能性。 翻译水平将通过多核糖体分析来研究。 的 在发育中表达的其它蛋白酪氨酸激酶的鉴定 男性细胞也将被追踪。

The long range objective of this research is to reach an understanding of molecular mechanisms that control mammalian sperm development. These studies will identify potential causes of human infertility and may suggest means to treat this problem. New approaches to male contraception are another possible benefit from research in this area. Interactions between germ cells and Sertoli cells in the seminiferous tubules are crucial for sperm development, but little has been learned to date about how these interactions are achieved at a molecular level. Protein-tyrosine kinases expressed in developing spermatocytes and spermatids are the focus of this application. Members of this enzyme family, through their roles in signal transduction, have been recognized as key regulatory molecules in the development of a variety of animal tissues and proteintyrosine kinases expressed in male germ cells are therefore strong candidates for roles as regulators of spermatogenesis. Through the use of a homology-based cDNA cloning strategy, a novel member of the protein-tyrosine kinase family, designated "PTK-Tl26", was identified that appears to be expressed in developing spermatocytes and/or spermatids. The specific research described in this application is designed to determine the mechanism that leads to the production of PTK-T126 and to characterize its cellular distribution and structural and biochemical properties. Specifically: structural features of PTK-Tl26 will be determined from an analysis of the amino acid sequence, which will be deduced from the nucleotide sequences of cDNA clones; the relationship between the testis-specific transcript that encodes PTK-Tl26 and a related, more widely expressed, transcript also will be determined through an inspection of cDNA sequences and by primer extension analysis; antibody reagents will be raised against PTK-Tl26 and will be used to detect the protein in testicular cells and to immunopurify the protein in order to assay for tyrosine kinase activity; and the potential for regulation of PTK-T126 expression at the translational level will be investigated by polysome analysis. The identification of other protein-tyrosine kinases expressed in developing male cells will also be pursued.