Liu H W, Shang S T, Chao C F, Muller C
Department of Biology and Anatomy, National Defense Medical Center, Taiwan, Republic of China.
Cell Tissue Res. 1991 Sep;265(3):409-14. doi: 10.1007/BF00340863.
A well-developed Golgi apparatus and rough and smooth endoplasmic reticulum in the principal cells of the mouse epididymis indicate active protein synthesis. Studies have shown that epididymal secretions are essential for sperm maturation. In a previous study, two wheat-germ agglutinin (WGA)-binding glycoproteins, GP-49 and GP-83, were identified on the surface of mature mouse sperm. In this study, synthesis and secretion of these two glycoproteins were investigated. Apparent WGA-binding was found on the stereocilia and in the apical region of principal cells in the corpus and cauda of epididymis. Post-fixation and pre-embedding cytochemical localization revealed that WGA-binding sites were situated in the Golgi apparatus, multivesicular bodies and stereocilia of principal cells. GP-49 and GP-83 were identified in the Nonidet P-40 homogenates of corpus and cauda epididymidis. In the epididymides of which ductuli efferentes had been ligated for more than 4 weeks, no sperm were found in the lumina of epididymal tubules. WGA-binding sites were present in the corpus and cauda; GP-49 and GP-83 were identified in tissue homogenates of the corpus and cauda as well. These findings suggest that GP-49 and GP-83 of mature sperm may be secreted by the principal cells of the corpus and cauda. These two molecules apparently conjugate to sperm whilst sperm transit through the epididymis.
小鼠附睾主细胞中发育良好的高尔基体以及粗面和滑面内质网表明其存在活跃的蛋白质合成。研究表明，附睾分泌物对精子成熟至关重要。在先前的一项研究中，在成熟小鼠精子表面鉴定出两种麦胚凝集素（WGA）结合糖蛋白，即GP-49和GP-83。在本研究中，对这两种糖蛋白的合成和分泌进行了研究。在附睾体和尾部主细胞的静纤毛以及顶端区域发现了明显的WGA结合。固定后和包埋前的细胞化学定位显示，WGA结合位点位于主细胞的高尔基体、多囊泡体和静纤毛中。在附睾体和尾部的Nonidet P-40匀浆中鉴定出了GP-49和GP-83。在输出小管结扎超过4周的附睾中，在附睾管腔中未发现精子。WGA结合位点存在于附睾体和尾部；在附睾体和尾部的组织匀浆中也鉴定出了GP-49和GP-83。这些发现表明，成熟精子的GP-49和GP-83可能由附睾体和尾部的主细胞分泌。这两种分子显然在精子通过附睾的过程中与精子结合。
