Antibodies to rat sperm tail polypeptides recognize Sertoli cell secretory proteins

Abstract

We have previously reported that (a) polyclonal antisera raised against rat Sertoli cell secretory protein S70 and S45-S35 heterodimeric protein recognize outer dense fiber polypeptides from rat sperm tail, and (b) protein S70 is antigenically related to polypeptides S45 and S35, the disulfide-linked components of the heterodimeric protein. We now report that polyclonal antisera generated against three different outer dense fiber polypeptides recognize (a) the putative antigen of the sperm tail and (b) Sertoli cell secretory protein S70 and its antigenically-related polypeptides. Immunogold electron microscopy shows that outer dense fibers of epididymal sperm crossreact with anti-S70 serum as well as with an antiserum raised against the polypeptide D complex of extracted outer dense fibers. Electron microscopy demonstrates that outer dense fibers consist of filamentous, coil-coiled units aligned side-by-side with each other. Results of this study strengthen the antigenic homology between Sertoli cell secretory proteins and outer dense fiber polypeptides of the sperm tail.

Immunogold electron microscopic localization of antigenic sites in the outer dense fiber region of rat sperm tail obtained by using antisera to two Sertoli cell secretory proteins

“…Immunogold electron microscopic studies show the localization of antigenic sites on mitochondrial capsules and the outer dense fiber region of sperm tail detected by antisera raised against Sertoli cell secretory glycoproteins. In addition, antisera raised against three different outer dense fiber polypeptides recognized protein S70 and S45-S35 heterodimeric protein in immunoblotting, immunoprecipitation and immunocytochemical experiments (Kierszenbaum et al, 1989).…”

“…Our electron microscopic study of negatively stained outer dense fibers demonstrates their side-by-side alignment tendency. It is possible that both alignment and assembly of outer dense @-helical fibers in a coil-coiled configuration (Kierszenbaum et al, 1989) may require the participation of polypeptides chemically unrelated to the keratin-like outer dense fibers but present in the outer dense fiber region. ACKNOWLEDGMENTS Dr. Hiroshi Ueda was a recipient of a Fogarty International Fellowship (1F05 TW0381).…”

“…Antisera raised against these two proteins have detected antigenic sites in the acrosome and in polypeptides extracted from sperm tail Kierszenbaum et al, 1988). Conversely, antisera raised against several outer dense fiber polypeptides extracted from sperm tail recognize the two Sertoli cell secretory glycoproteins (Kierszenbaum et al, 1989). This antigenic homology between two Sertoli cell secretory proteins and sperm tail polypeptides, detected by immunoblotting and immunocytochemistry, suggests a structural relationship.…”

Active cell death in hormone-dependent tissues

“…TRPM-2 has been implicated in numerous processes in addition to its proposed involvement in ACD, including a role in chromaffin granule secretion [131], in spermatogenesis [124,125,152,153], in immune regulation [129,151,[154][155][156][157][158], in regulation of lipid transport [127,159], and in morphological transformation [132]. In all but one of these systems there is no definitive biochemical evidence to support a specific function for TRPM-2.…”

“…Thus the induction of TRPM-2 in the course of ACD may protect both the apoptotic cell and its vital neighbors from complement attack. The association of SGP-2 with the membrane of developing sperm [146,152,153] in the male reproductive tract may also be essential for maintaining sperm integrity and the survival of the sperm in both the male and female reproductive tracts.…”