Different expression time of the 105‐kDa protein and 90‐kDa heat‐shock protein in rat testis

Abstract
To understand the physiological functions of the 105-kDa protein which is testis-specific and HSP90 (90-kDa heat-shock protein) related protein. the appearance of it in the testis has been followed during the development of rat. On immunoblotting analysis. the 105-kDa protein did not appear until after the age of five weeks, while HSP90 could be detected at three weeks. In the spermatozoa. the 105-kDa protein was much abundant but not in the LC-540 cells (a cell line from Leydig cell tumor in rat testis) cytosol. This finding has attracted much attention to the relationship between this protein and sperm functions.