Tanii Ichiro, Yagura Tetsuya, Inagaki Naoyuki, Nakayama Tatsuo, Imaizumi Kazunori, Yoshinaga Kazuya
Division of Molecular and Cellular Biology, Department of Anatomy, Faculty of Medicine, University of Miyazaki, Miyazaki 889-1692, Japan.
Acta Histochem Cytochem. 2007 Feb 27;40(1):19-26. doi: 10.1267/ahc.06020. Epub 2007 Feb 5.
The proper assembly of sperm flagellar proteins is fundamental for sperm motility. The sperm- and spermatid-specific isoform of glyceraldehyde 3-phosphate dehydrogenase, GAPDS, is a flagellar protein indispensable for sperm flagellar movement. To obtain information on the assembly of the glycolytic enzyme into the flagellum, the precise localization of rat GAPDS in the flagellum and the stage of incorporation into the flagellum were examined using a monoclonal antibody. Immunolocalization of rat GAPDS was restricted to the fibrous sheath (FS) in the sperm flagellum, and was predominant in the circumferential ribs rather than the longitudinal columns. Immunoreactivity was first detected in the cytoplasm and flagella of the step-16 spermatids during the final step of FS formation. Together with the expression of other FS proteins, the present results indicate the sequential assembly of FS components, suggesting that the expression and transport of GAPDS is regulated in a coordinated manner during sperm flagellar formation.
精子鞭毛蛋白的正确组装对于精子运动至关重要。甘油醛-3-磷酸脱氢酶的精子和精子细胞特异性同工型GAPDS是一种鞭毛蛋白，对于精子鞭毛运动不可或缺。为了获取有关糖酵解酶组装到鞭毛中的信息，使用单克隆抗体检测了大鼠GAPDS在鞭毛中的精确定位以及整合到鞭毛中的阶段。大鼠GAPDS的免疫定位仅限于精子鞭毛中的纤维鞘（FS），并且在圆周肋而非纵向柱中占主导地位。在FS形成的最后阶段，首次在第16步精子细胞的细胞质和鞭毛中检测到免疫反应性。与其他FS蛋白的表达一起，目前的结果表明FS成分的顺序组装，表明在精子鞭毛形成过程中GAPDS的表达和运输以协调的方式受到调节。
