Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P56851 (epididymal)
 11,273 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Monoclonal antibody 4E9, which was raised against a partially purified detergent extract of rat caudal epididymal sperm, recognizes the tail of sperm from the cauda, but not from caput epididymidis, as well as epithelial cells in a restricted region of the distal caput/corpus epididymidis and proteins in epididymal fluid from corpus and cauda epididymidis. The antigen is apparently a glycoprotein, since it is retained on a Ricinus communis agglutinin I lectin column. Epididymal fluid antigens have apparent M(rs) of 38-26 kD, whereas the membrane-associated form of the molecule has an M(r) of 26 kD. Immunocytochemical data and Western immunoblot data suggest that the membrane antigen is derived from the fluid antigen, which, in turn, is secreted by the epididymal epithelium. Characterization of the membrane antigen indicates that it is tightly associated with the sperm surface, behaving as though it is an integral membrane protein. The antigen persists on ejaculated sperm.
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PMID:Rat epididymis-specific sperm maturation antigens. I. Evidence that the 26 kD 4E9 antigen found on rat caudal epididymal sperm tail is derived from a protein secreted by the epididymis. 817 1

We examine here the biochemical properties and epididymal localization of a maturation dependent ram sperm surface antigen. A monoclonal antibody, ESA152, identifies an antigen that is present on the surface of ejaculated sperm, but is absent from testicular sperm. Crosslinking of the ESA152 antigen with bivalent antibodies induces the acrosome reaction, redistributing the antigen into the anterior region of the sperm head where it associates with the fusion product of the plasma membrane and the outer acrosomal membrane. The ESA152 antigen appears as a polypeptide of 18 kDa on immunoblots of SDS-polyacrylamide gels. The ESA152 epitope includes the sialic acid termini of N-linked oligosaccharides, as shown by its sensitivity to neuraminidase and endoglycosidase F. The ESA152 antigen is a highly hydrophobic integral membrane protein that resists aqueous extraction, partitions into the detergent phase of Triton-X-114, and solubilizes in chloroform-methanol mixtures. The anchoring of ESA152 is unaffected by phosphtidylinositol specific phospholipase C. The antigen is absent from extracts of caput and corpus epididymidis but appears abruptly in the first segment of the cauda. Immunofluorescence reveals that the ESA152 epitope first appears in clusters of cells in the luminal epithelium of the proximal cauda, prior to or concurrent with its appearance on sperm.
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PMID:Biochemical characterization and epididymal localization of the maturation-dependent ram sperm surface antigen ESA152. 835 35

Cellular junctions in the testis and epididymis play crucial roles for the development and maturation of spermatozoa. In the testis, tight junctions between Sertoli cells form a functional blood testis barrier between 10 and 16 days of age, whereas the tight junctional blood epididymal barrier between adjacent epithelial cells is formed between days 18 and 21. In the present study, occludin, a constituent integral membrane protein of tight junctions, was localized by immunofluorescent confocal microscopy in embryonic (days 13.5-18.5), postnatal (days 5-23) and adult (day 70) mouse testes and epididymides to correlate its expression with the onset of tight junctions and eventual formation of these barriers. At embryonic days 13.5 and 16.5, low diffuse cytoplasmic levels of occludin were observed in cells of the testicular cords. By embryonic day 18.5, the level of occludin was still low but appeared as a filiform-like network streaming toward the center of the cord. At postnatal days 5 and 7 immunostaining became more intense and appeared to outline the periphery of Sertoli cells of seminiferous tubules. Postnatal day 14 marked the appearance of an intense, focal band-like localization of occludin at the base of the tubules, correlating with the appearance of a functional blood-testis barrier. By day 23 and in adults, expression of occludin was noted at the base of the tubule appearing as intense, wavy, discontinuous bands similar in appearance irrespective of the stage of the seminiferous epithelium cycle. In the developing epididymis, intense cytoplasmic immunostaining was present in epithelial cells of many epididymal tubules at embryonic day 13.5. By embryonic day 16.5, intense occludin immunostaining appeared along the lateral plasma membranes of epithelial cells, whereas at embryonic day 18.5, immunostaining was punctate and apically located, suggesting the presence of tight junctions by this age; similar immunostaining was noted at postnatal days 5 and 7. In the adult epididymis, distinct punctate apical staining was observed between adjacent principal cells of all epididymal regions except the proximal initial segment, where occludin was found only in association with narrow cells. These results indicate that in the epididymis, the appearance of occludin at apical sites between adjacent epithelial cells occurs during embryonic development suggesting that tight junctions form earlier than in the testis. While occludin was expressed in a similar pattern between Sertoli cells at all stages of the cycle in the adult testis, its expression in the adult epididymis was cell- and region-specific. Taken together these data suggest that different factors regulate occludin expression in the testis and epididymis.
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PMID:Cellular immunolocalization of occludin during embryonic and postnatal development of the mouse testis and epididymis. 1043 43