ACROSOME BIOGENESIS BEGINS DURING MEIOSIS - EVIDENCE FROM THE SYNTHESIS AND DISTRIBUTION OF AN ACROSOMAL GLYCOPROTEIN, ACROGRANIN, DURING GUINEA-PIG SPERMATOGENESIS
ACROSOME BIOGENESIS BEGINS DURING MEIOSIS - EVIDENCE FROM THE SYNTHESIS AND DISTRIBUTION OF AN ACROSOMAL GLYCOPROTEIN, ACROGRANIN, DURING GUINEA-PIG SPERMATOGENESIS
复制标题
DOI：
10.1095/biolreprod42.2.317
复制
发表时间：
1990-02-01
影响因子：
3.6
通讯作者：
GERTON, GL
中科院分区：
文献类型：
--
作者：
ANAKWE, OO;GERTON, GL
使用顶体糖蛋白作为发育标志物研究了精子特异性细胞器顶体的生物发生。我们将这种成分命名为 acrogranin，是通过标准色谱程序从豚鼠睾丸的酸提取物中纯化出来的。通过分析十二烷基硫酸钠-聚丙烯酰胺凝胶电泳测定还原的顶峰素的分子量为67,000。用纯化的顶粒素免疫雌性兔子，产生的抗血清可识别豚鼠睾丸酸提取物中 Mr = 67,000 的单一蛋白质。通过间接免疫荧光法，仅在成熟精子的顶体中发现了顶粒素。在单倍体精细胞中，顶粒蛋白定位于正在发育的顶体中，并且微弱地定位于细胞质中。在减数分裂细胞（粗线期精母细胞）推定的顶体原颗粒的细胞质和核旁区域也检测到了顶粒素。来自不同纯化生殖细胞群的洗涤剂提取物仅含有 Mr = 67,000 形式的顶粒素，但精子提取物具有睾丸提取物中不存在的四种较低的 Mr 免疫反应形式。通过二维凝胶电泳，发现acrogranin是一种酸性糖蛋白。对糖基化和三氟甲磺酸去糖基化的 acrogranin 的分析表明该抗体识别多肽决定簇。将高度富集的生殖细胞群用 [35S] 蛋氨酸标记过夜并用去污剂提取后，抗顶峰蛋白免疫沉淀出 Mr = 67,000 的单一蛋白。粗线期精母细胞和圆形精子细胞合成顶峰素的情况相似，但浓缩精细胞合成糖蛋白的量明显减少。这些研究表明，顶体生物发生（由特定顶体成分的合成决定）在减数分裂期间开始，并持续到精子发生的早期阶段。
The biogenesis of the sperm-specific organelle, the acrosome, was investigated using an acrosomal glycoprotein as a marker of development. This component, which we have named acrogranin, was purified from an acid extract of guinea pig testes by standard chromatographic procedures. The molecular weight of reduced acrogranin was determined to be 67,000 by analytical sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Immunization of female rabbits with purified acrogranin produced an antiserum that recognized a single protein with Mr = 67,000 in an acid extract of guinea pig testes. By indirect immunofluorescence, acrogranin was found only in the acrosome of mature sperm. In haploid spermatids, acrogranin was localized in the developing acrosome and, weakly, in the cytoplasm. Acrogranin was also detected in the cytoplasm and juxtanuclear region in putative proacrosomal granules of meiotic cells (pachytene spermatocytes). Detergent extracts from different purified germ cell populations contained only the Mr = 67,000 form of acrogranin, but sperm extracts had four lower Mr immunoreactive forms not present in the testicular extracts. By two-dimensional gel electrophoresis, acrogranin was found to be an acidic glycoprotein. Analysis of glycosylated and trifluoromethanesulfonic acid-deglycosylated acrogranin indicated that the antibody recognized polypeptide determinants. After highly enriched germ cell populations were labeled overnight with [35S]methionine and extracted with detergent, antiacrogranin immunoprecipitated a single protein of Mr = 67,000. The synthesis of acrogranin by pachytene spermatocytes and round spermatids was similar, but the synthesis of the glycoprotein by condensing spermatids was markedly reduced. These studies demonstrate that acrosome biogenesis, as determined by the synthesis of a specific acrosomal component, begins during meiosis and continues through the early stages of spermiogenesis.