Developmental expression of G protein alpha subunits in mouse spermatogenic cells: evidence that G alpha i is associated with the developing acrosome.
Developmental expression of G protein alpha subunits in mouse spermatogenic cells: evidence that G alpha i is associated with the developing acrosome.
复制标题
小鼠生精细胞中 G 蛋白 α 亚基的发育表达：G α i 与顶体发育相关的证据。
DOI：
10.1016/0012-1606(92)90146-8
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发表时间：
1992
影响因子：
2.7
通讯作者：
Gerton,GL
中科院分区：
文献类型：
--
作者：
Karnik,NS;Newman,S;Kopf,GS;Gerton,GL
鸟嘌呤核苷酸结合蛋白（G蛋白）是存在于所有细胞中的重要信号转导分子。G蛋白与顶体完整精子的质膜/顶体外膜区域相关，并且至少一种G蛋白参与透明质酸诱导的顶体反应。为了阐明这些蛋白在精子发生过程中的功能，我们研究了生精细胞中G蛋白的类型以及它们何时与发育中的顶体相关联。使用细菌毒素催化的[32 P] ADP-核糖基化结合免疫沉淀和免疫荧光，利用针对各种G蛋白同种型的特定区域的抗体，在小鼠精母细胞和精子细胞中检测到Gi 1，Gi 2，Gi 3和Gowere的α亚基。一种识别位于精母细胞前顶体颗粒和精子细胞发育中顶体的Gα i亚型保守序列的抗血清。随着精母细胞向精子细胞的发育，Gα水平逐渐降低，附睾尾精子中未检测到Gα o。使用Gα o特异性抗血清的免疫反应性在任何生精细胞类型中均未显示出明显的区域化。在生精细胞和精子中未检测到Gα s。Gα i与发育中的顶体的关联表明G蛋白可能在顶体生物发生中起作用，并且是随后导致顶体胞吐的信号转导所需的复合物的一部分。
Guanine nucleotide-binding proteins (G proteins) are important signal transducing molecules found in all cells. G proteins are associated with the plasma membrane/outer acrosomal membrane region of acrosome-intact sperm and at least one G protein is involved in the zona pellucida-induced acrosome reaction. With the goal of elucidating the functions of these proteins during spermatogenesis, we investigated the types of G proteins present in spermatogenic cells and when they first become associated with the developing acrosome. Using bacterial toxin-catalyzed [32P]ADP-ribosylation in conjunction with immunoprecipitation and immunofluorescence utilizing antibodies directed against specific regions of various G protein isotypes, the α subunits of Gi1, Gi2, Gi3, and Gowere detected in mouse spermatocytes and spermatids. An antiserum recognizing a conserved sequence of Gαisubtypes localized to the proacrosomal granules of spermatocytes and the developing acrosome of spermatids. Levels of Gαodiminished as spermatocytes developed into spermatids such that Gαowas not detected in cauda epididymal sperm. Immunoreactivity using Gαo-specific antisera did not display a distinct regionalization within any of the spermatogenic cell types. Gαswas not detected in the developing spermatogenic cells or sperm. The association of Gαiwith the developing acrosome suggests a role for G proteins may have a role in acrosome biogenesis as well as being part of a complex required later for signal transduction leading to acrosomal exocytosis.