ACROSOMAL ENZYME BIOSYNTHESIS BY MAMMALIAN SPERMATIDS

精子顶体酶的生物合成 将研究细胞以确定这些酶是否 以类似于用于输送酸的方式处理 水解酶转化为溶酶体。 将制备豚鼠精子， 诱导与离子载体发生顶体反应 A23187。 可溶性顶体成分从顶体中释放出来， 将收集精子并用作两个顶体的来源 酶：顶体酶原/顶体酶和β-半乳糖苷酶。 单克隆 将制备针对这些酶的抗体， 通过纯化的豚鼠群体研究它们的合成 粗线期精母细胞、圆形精子细胞和浓缩 精子细胞。 使用细胞提取物的免疫印迹， 免疫荧光和免疫沉淀法 代谢标记的生精细胞， 抗体将用于确定哪些细胞类型能够 合成顶体酶原和β-半乳糖苷酶。 使用脉冲- chase标记，然后免疫沉淀， 顶体酶原和β-半乳糖苷酶的前体形式将 在生精细胞培养中检查。 实验也将 以确定甘露糖-6-磷酸基团 与新合成的顶体蛋白原和β- 半乳糖苷酶。 将测定每个生精细胞群 对于甘露糖-6-磷酸受体， 免疫荧光和受体活性测定。 生精细胞也将被测试其能力， 内化牛睾丸β-半乳糖苷酶（模型 溶酶体酶）、豚鼠顶体酶原和豚鼠精子 甘露糖-6-磷酸受体介导的β-半乳糖苷酶 内吞作用 该项目期间进行的实验将 提供有关综合报告的重要新信息， 顶体酶的加工和运输。 增加 关于顶体发育的信息 促进我们对男性生育力调节的理解。

The biosynthesis of acrosomal enzymes by isolated spermatogenic cells will be investigated to determine whether these enzymes are processed in a manner similar to that used to deliver acid hydrolases to lysosomes. Guinea pig sperm will be prepared and induced to undergo the acrosome reaction with the ionophore A23187. The soluble acrosomal components released from the sperm will be collected and used as the source for two acrosomal enzymes: proacrosin/acrosin and beta-galactosidase. Monoclonal antibodies will be prepared against these enzymes and used to study their synthesis by purified populations of guinea pig pachytene spermatocytes, round spermatids, and condensing spermatids. Using immunoblotting of cell extracts, immunofluorescence, and immunoprecipitation of extracts from metabolically labeled spermatogenic cells, the monoclonal antibodies will be used to determine what cell types are capable of synthesizing proacrosin and beta-galactosidase. Using pulse- chase labeling followed by immunoprecipitation, the processing of precursor forms of proacrosin and beta-galactosidase will be examined in spermatogenic cell cultures. Experiments will also be performed to determine whether mannose-6-phosphate groups are attached to the newly-synthesized proacrosin and beta- galactosidase. Each spermatogenic cell population will be assayed for mannose-6-phosphate receptor by immunoblotting, immunofluorescence, and as receptor activity assay. Spermatogenic cells will also be tested for their ability to internalize bovine testicular beta-galactosidase (a model lysosomal enzyme), guinea pig proacrosin, and guinea pig sperm beta-galactosidase via mannose-6-phosphate receptor-mediated endocytosis. The experiments performed during this project will provide important new information concerning the synthesis, processing and transport of acrosomal enzymes. Increased information concerning the development of the acrosome will advance our understanding of the regulation of male fertility.