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: 6301876
• 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/6301876
• 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穿过 曲细精管近腔室的基膜 上皮细胞，在那里完全发育的精子细胞（精子）可以 释放到管状腔中。 它们之间的特殊连接 支持细胞以及支持细胞和生殖细胞之间必须 不断地被破坏、再生和/或替换。 因此，在本发明中， 蛋白酶、蛋白酶抑制剂和连接复合物（JC）组分 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 周期未知。在过去的两个月里， 实验室已经证明了支持和生殖细胞背后的血液- 睾丸屏障释放多种蛋白质， 在生殖细胞迁移中。 更重要的是，生殖细胞已经被证明 释放出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。其中一 分子，命名为germease，一种41 kDa的睾丸蛋白， 独特的部分N-末端氨基酸序列，已从 生殖细胞条件培养液（GCCM）。 Germease可能在生殖细胞迁移中起关键作用， 具有两种独特的生物学功能。 一是 一种通过抑制睾丸素产生的Sertoki细胞调节剂， 连接复合物组分;和丛生蛋白，一种可以 诱导细胞聚集。因此，这两种分子都参与了细胞内 睾丸内的结合。 其次，germease是一种蛋白酶，能够 水解细胞外基质的组分，例如胶原蛋白。 的 Germease的主要作用是浓度依赖性的。 在这个新的补助金期间，P.I.将检查 生殖酶在睾丸中的作用，也将表征其生物学特性 行动上 此外，PI。建议使用germease，并选择 蛋白酶，蛋白酶抑制剂，和JC组分中确定的， 和其他实验室作为标记， 在生精周期的不同阶段， 原位杂交结合北方印迹迁移 分析. 这样一幅合成图涉及这些分子 生殖细胞迁移将有助于鉴定生殖细胞迁移的靶点。 干预破坏精子发生，这可能成为一个新的 发展男性避孕方法。