Acrosome Biogenesis in the Hamster: DISCUSSION(3)
Although the mature AM22 and AM29 polypeptides are assembled into a Triton X-100-insoluble acrosomal matrix assembly in epididymal spermatozoa, the 40-kDa putative precursor protein of the round spermatids is readily soluble in Triton X-100. It is possible that size processing of the precursor polypeptide is required for the assembly of the insoluble matrix elements, and this is under current investigation. It is also possible that processing of the precursor protein is required for the binding of the matrix to the outer acrosomal membrane; this possibility, too, is under investigation. flovent inhaler
In other species, including the baboon, human, and mouse, the testicular forms of the SP10 or SPlO-related polypeptides are high-molecular-weight precursors of the mature polypeptides found in epididymal spermatozoa . Although several high-molecular-weight precursor forms of mSPIO have been identified in the mouse testis , we found only a single immunologically reactive band of 40 kDa in hamster round spermatids. This may reflect species differences, but we may identify intermediate forms in the hamster as more mature spermatids are examined.