BIOLOGY OF GERM CELL MIGRATION IN SPERMATOGENESIS

精子发生过程中生殖细胞迁移的生物学

• 批准号: 6108354
• 负责人: C Y CHENG
• 金额: $ 23.88万
• 依托单位: POPULATION COUNCIL
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-04-01 至 2000-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6108354
• 关键词: Sertoli cells; cell cycle; cell migration; complementary DNA; endopeptidases; enzyme activity; enzyme induction /repression; germ cells; immunocytochemistry; immunoprecipitation; in situ hybridization; laboratory rabbit; laboratory rat; messenger RNA; northern blottings; nucleic acid sequence; protease inhibitor; secretion; spermatogenesis; testis; tissue /cell culture

During spermatogenesis, developing germ cells must traverse from the basal lamina to the adluminal compartment of the seminiferous epithelium where fully developed spermatids (spermatozoa) can be released into the tubular lumen. The specialized junctions between Sertoli cells as well as between Sertoli and germ cells must be continuously disrupted, regenerated and/or replaced. Thus, proteases, protease inhibitors, and junctional complex (JC) components are involved in these events. However, the likely sequence of events involving these molecules at different stages of the spermatogenic cycle is not known. During the past two grant periods, this laboratory has demonstrated Sertoli and germ cells behind the blood- testis barrier release multiple proteins that are likely to be involved in germ cell migration. More important, germ cells have been shown to release several molecules having multiple biological activities suggesting they play an active role in their migration. One of these molecules, designated germease, a 41 kDa testicular protein with a unique partial N-terminal amino acid sequence, has been purified from germ cell-conditioned medium (GCCM) during the past grant period. Germease is likely to play a critical role in germ cell migration since was shown to possess two distinctive biological functions. First, it is a Sertoki cell modulator by inhibiting the production of testin, a junctional complex component; and clusterin, a molecule that can induce cell aggregation. Thus, both molecules are involved in cellular association tin the testis. Second, germease is a protease capable of hydrolyzing components of extracellular matrix such as collagen. The primary action of germease was shown to be concentration dependent. During this new grant period, the P.I. will examine the physiological role of germease in the testis and will also characterize its biological action. In addition, the P.I. proposes to use germease and selected proteases, protease inhibitors, and JC components identified in this and other laboratories as markers to construct the cascade of events at different sages of the spermatogenic cycle leading to germ cell migration by in situ hybridization in conjunction with Northern blot analysis. Such a composite picture involving these molecules leading to germ cell migration will be useful in identifying target(s) of intervention to disrupt spermatogenesis which may become a new approach for male contraceptive development.

在精子发生过程中，发育中的生殖细胞必须从 基板至输精管的侧脑室 发育完全的精子细胞(精子)所在的上皮 释放到管腔内。它们之间的特殊交汇点 支持细胞以及支持细胞和生殖细胞之间必须 持续中断、再生和/或更换。因此， 蛋白水解酶、蛋白水解酶抑制剂和连接复合体(JC)成分 都参与了这些事件。然而，事件的可能顺序 在精子发生的不同阶段涉及这些分子 周期尚不清楚。在过去的两个资助期内，这 实验室已经证明了血液背后的Sertoli和生殖细胞- 睾丸屏障释放多种可能参与其中的蛋白质 在生殖细胞迁移中。更重要的是，生殖细胞已经被证明 释放几个具有多种生物活性的分子 这表明它们在迁徙过程中发挥了积极作用。这其中的一个 分子，命名为Germease，是一种41 kDa的睾丸蛋白，具有 唯一的部分N-末端氨基酸序列，已从 过去赠款期间的生殖细胞条件培养液(GCCM)。 Germease可能在生殖细胞迁移中发挥关键作用，因为 被证明具有两种独特的生物学功能。首先，它是 一种Sertoki细胞调节剂，通过抑制的产生，a 以及簇蛋白，一种可以 诱导细胞聚集。因此，这两个分子都参与了细胞 睾丸内的联系。其次，胚胎酶是一种能够 分解细胞外基质的成分，如胶原蛋白。这个 Germease的初级作用具有浓度依赖性。 在新的授权期内，私家侦探将检查 生殖酶在睾丸中的作用，也将表征其生物学特性 行动。此外，私家侦探建议使用Germease和选定的 在本研究中确定的蛋白水解酶、蛋白水解酶抑制剂和JC组分 和其他实验室作为构建事件级联的标记 在生精周期的不同阶段通向生殖细胞 原位杂交结合Northern印迹的迁移性 分析。这样一幅涉及这些分子主导的合成图片 对生殖细胞的迁移将有助于识别靶细胞(S) 干扰精子发生的干预措施可能成为一种新的 开发男性避孕药具的方法。