EXPRESSION OF PREPROENKEPHALIN-LIKE MRNA IN THE TESTIS

旁分泌相互作用在细胞通讯中起着重要的作用 在睾丸内。阿片肽及其受体的存在， 睾丸表明，这种肽家族至少可以发挥作用， 部分作为睾丸功能的局部调节器。PI成功了 在鉴定多种睾丸细胞类型中， 阿片肽前体，前脑啡肽：生精细胞， 支持细胞。因此，脑啡肽原衍生肽可介导 体细胞和雄性生殖细胞的睾丸内活动， 对调节精子发生很重要。此外，大鼠和 小鼠生精细胞含有一种独特的1700个核苷酸的形式， 脑啡肽原RNA，在体细胞中未发现， 监管.因此，前脑啡肽原基因可以作为一个模型， 生殖细胞基因表达的调控。 本研究的目的是：（1）确定顺式作用的分子结构， 脑啡肽原基因内负责其表达的元件， 生精细胞发育阶段特异性调节：和（2） 表征脑啡肽原RNA衍生的翻译产物 在不同的睾丸细胞中存在。后者 实验对于最终阐明 睾丸前脑啡肽衍生肽的功能。

Paracrine interactions play an important role in cellular communication within the testis. The presence of opioid peptides and their receptors in the testis has suggested that this peptide family may function, at least in part, as local regulators of testicular function. The PI has succeeded in identifying multiple testicular cell types that express the gene for the opioid peptide precursor, proenkephalin: spermatogenic cells and Sertoli cells. Proenkephalin-derived peptides therefore may mediate intratesticular actions of somatic as well as male germ cells that are important for the regulation of spermatogenesis. In addition, rat and mouse spermatogenic cells contain a unique 1700-nucleotide form of proenkephalin RNA, not found in somatic cells, that is developmentally regulated. The proenkephalin gene thus serves as a model for the regulation of germ-cell gene expression. The aims of this proposal are: (1) to characterize the cis-acting elements within the proenkephalin gene responsible for its expression and developmental stage-specific regulation in spermatogenic cells: and (2) to characterize the translation products derived from proenkephalin RNA in the different testicular cells in which it is present. The latter experiments will be important for the ultimate elucidation of the functions of testicular proenkephalin-derived peptides.