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)

A rabbit antibody to mouse 3T3 cell fibronectin was used in conjunction with a fluorescein-tagged second antibody to detect fibronectin-like activity on the surface of rabbit spermatozoa. Only ejaculated sperm displayed an intense and highly localized fluorescence over the acrosomal region. Cauda epididymal sperm of the rabbit as well as several other species did not exhibit any reaction. The fluorescent activity could be eliminated by trypsin treatment but was re-established by incubation in cell-free seminal fluid. Sperm recovered from females 10-12 h after mating showed a reduction or absence of antifibronectin fluorescence, suggesting that this component's loss could be a factor in sperm capacitation. Because fibronectins show strong binding to collagen, mixtures of ejaculated sperm and collagen were examined in the light and electron microscope. Living sperm appear to have a strong affinity for collagen and quickly adhere to the filaments by their heads, while continuing vigorous flagellations. Surface labeling of sperm with the galactose-oxidase-NaB[3H]4 technique, extraction with urea-detergent mixtures and affinity chromatography of extracts on gelatin-Sepharose revealed a single radioactive band of mot wt approximately 40,000 after SDS polyacrylamide gel electrophoresis and fluorography.
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PMID:A collagen-binding protein on the surface of ejaculated rabbit spermatozoa. 699 66

Autoantibodies raised in guinea pigs (GP) by hyperimmunization with epididymal sperm recognize antigens present on the plasma membrane of intact sperm and antigens associated with acrosome-reacted sperm. Plasma membrane autoantigens were characterized by SDS-PAGE analysis of immune precipitates from detergent extracts of radiolabeled epididymal sperm. Three major protein bands with approximate molecular weights (MW) of 69,000, 62,000 and 40,000 daltons were exhibited. Galactose oxidase and periodate oxidation followed by tritiation revealed two major plasma membrane glycoprotein autoantigens with MWs of 35,000 and 32,000 daltons and one sialoglycoprotein of 34,000 daltons. Antigenic molecules of similar MW were also detected by autoantisera to guinea pig testicular homogenates. Immune precipitates of radiolabeled detergent extracts of acrosome-reacted sperm analyzed by SDS-PAGE exhibited two major carbohydrate-containing peaks, one with a MW of approximately 42,000 daltons and one of 6,000 daltons. Since the 6,000 dalton peak was immunoprecipitated from the organic phase of both chloroform:methanol 2:1 and n-butanol extracts, the antigen may be a glycolipid. The possible existence of glycolipid autoantigen in GP sperm was further supported by the reaction in a solid phase radioimmunoassay of autoantibodies to GP sperm with glycolipid extracts from GP testis. This study demonstrates the presence of multiple autoantigenic specificities in the sperm-plasma membrane, acrosome-reacted sperm and testis of guinea pigs. It also demonstrates for the first time glycolipid autoantigens in testis and sperm.
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PMID:Immunochemical analysis of guinea pig sperm autoantigens. 703 3

Non-motile spermatozoa freshly extruded from the rat caudal epididymis can be initiated to full motility immediately after diluting with 0.9% NaCl. The motility initiation was dependent on the pH, viscosity and osmolality of diluent. Diluent with pH 4 to 8 could optimally initiate the motility. Osmolality of most diluents suitable for the initiation was between 130 to 600 mOsm/kg. The motility initiation was inhibited by Hg2+ greater than Cu2+ greater than Cd2+, chlorpromazine, Triton X-100 and SDS. The following compounds showed essentially no inhibitory effect: EGTA, chlortetracycline, calcein, ruthenium red, phloridzin, myo-inositol and carnitine. The findings suggested that spermatozoa were kept in quiescence in the cauda epididymis not by the pH, osmolality, viscosity, myo-inositol, carnitine, Ca2+ or K+ of the caudal epididymal fluid. It was also suggested that motility initiation did not involve Ca2+, calmodulin and transport of Ca2+ or glucose across sperm membrane.
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PMID:Motility initiation of quiescent spermatozoa from rat caudal epididymis: effects of pH, viscosity, osmolality and inhibitors. 714 26

During their period of activity, epithelial cells of the lizard epididymis produce secretory granules containing highly insoluble central cores of protein nature (protein H). After centrifugation of the epididymal fluid at 15 000 X g, major soluble proteins were separated in the supernatant by polyacrylamide gel electrophoresis. These proteins were labelled by repeated injections of [3H]leucine into animals. In cylindrical gel electrophoreses, labelled proteins migrated as a single band towards the anode in the presence of SDS, and as two separate bands without SDS. The fastest component obtained in non-denaturing conditions was designated protein L. In two-dimensional gel electrophoreses, the two bands separated in the first dimension both migrated to the same position in the second dimension with SDS. Consequently it may be assumed that protein L is a monomer (molecular weight about 16 000-20 000) able to aggregate into polymers which can be dissociated with SDS. It was proved by hemicastration experiments that these soluble proteins did not originate from the testis. In addition, they were detected after short incubation of epididymal tissues in the presence of [3H]leucine. It is concluded that these proteins are elaborated by epithelial cells of the epididymis and discharged into the lumen. A possible role in the physiology of spermatozoa is briefly discussed.
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PMID:Major proteins secreted by the epididymis of Lacerta vivipara. Identification by electrophoresis of soluble proteins. 721 5

The surface proteins of bull spermatozoa from caput and cauda epididymis were labelled by lactoperoxidase-catalyzed radioiodination and solubilized and analyzed by SDS-PAG-electrophoresis. The surface protein patterns of caput and cauda epididymal spermatozoa resembled each other but some distinct differences could be found. Caput epididymal spermatozoa revealed a protein peak with molecular weight of 15 000 - 18 000 daltons but this peak was not found on cauda epididymal spermatozoa. On caput epididymal spermatozoa the most intensely labelled protein peak was located between 90 000 and 100 000 daltons but on cauda epididymal spermatozoa the corresponding peak was only weakly labelled and had a molecular weight of 80 000 - 90 000 daltons. Surface protein with molecular weight of 42 000 - 47 000 daltons was dominating on cauda epididymal spermatozoa. The surface protein structure of cytoplasmic droplets did not drastically differ from that of epididymal spermatozoa.
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PMID:Changes in surface protein structure of bull spermatozoa during epididymal maturation. 726 88

Lizard epididymis produces large secretory granules (6 micrometer) which are discharged and mix with the spermatozoa. They consist of a dense central core and a peripheral vacuole. Central cores were prepared by two means: (1) homogenization of epididymal cells than isolation of a granular fraction by centrifugation on a discontinuous sucrose density gradient as a final step, and (2) collection of epididymal fluid containing both granules and spermatozoa, and separation of these elements by several steps of low speed centrifugations and washings. Purity of the different fractions was checked by microscopy. After complete dissolution in Triton X-100 (2.5%), the fractions containing central cores were submitted to SDS-polyacrylamide gel electrophoresis (15% acrylamide bisacrylamide). When apparently free from surrounding material, the dissolved central cores analyzed by electrophoresis showed only a main band representing a single protein (or a small group of proteins) of relative low mobility (molecular weight about 70 000). Other more mobile proteins have been identified in less purified fractions. They probably originate from the peripheral vacuole but this point is still under investigation. These two types of proteins do not originate from plasma or testis. Their androgen dependence is discussed.
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PMID:Major proteins secreted by the epididymis of Lacerta vivipara. Isolation and characterization by electrophoresis of the central core. 735 25

A method has been developed to study the mechanism of epididymal secretion in the anesthetized rat in vivo. Secretion of the cauda epididymidis was affected by altering the intraluminal calcium ion concentration. Removal of calcium caused a rise and high calcium (10 X normal) caused a fall in the rate of secretion. Exocytosis did not seem to be operative in the epididymidis. The perfusate collected from the cauda epididymidis stimulated the forward motility of the washed caudal epididymal spermatozoa. This effect was concentration-dependent. At low concentration the perfusate stimulated the forward motility and at high concentration it caused a fall. A similar relationship between concentration and effect was noted for the epididymal plasma. When the diluted perfusate was used as the stimulant, there was a time lag of 15 min before any stimulation of forward motility was observed. However, the effect of the diluted epididymal plasma was immediate. The effect of the perfusate but not the plasma was inhibited by pretreatment of the sperm with cyclohexamide (10(-4) M). This difference in the action of the two fluids was discussed in relation to the proteins present in the fluids as revealed by SDS polyacrylamide gel electrophoresis.
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PMID:Secretion of the rat cauda epididymidis. 744 34

Protease and basic amidase activity was found in the seminal plasma of the domestic turkey. Amidase activity, measured through use of N-alpha-benzoyl-DL-arginine-p-nitroanilide-HCL (BAPNA), was 23-28 times greater for turkey than for guinea fowl or chicken. Within the reproductive tract, seminal plasma from the vas deferens had much greater activity than testicular or epididymal fluids. Turkey seminal plasma enzyme (TSPE) purified by chromatography or isoelectric focusing showed three protein bands by PAGE, each resolving on SDS-PAGE into two subunits with molecular weights of approximately 28,000-32,000 and 38,000-44,000. One of the three proteins also contained a larger subunit (M(r) 76,000-81,000) thought to be transferrin. Turkey acrosin consisted of three subunits with molecular weights below 20,500. Acrosin, but not TSPE, was visualized in native gels with N-alpha-benzoyl-DL-arginine-beta-naphthylamide (BANA)/Fast Garnet stain. Michaelis constants (BAPNA) for TSPE, acrosin, and trypsin were 2.41 +/- 0.12 x 10(-4) M (n = 5), 4.96-6.03 x 10(-4) M (n = 2), and 6.76 +/- 0.95 x 10(-4) M (n = 6), respectively. TSPE, like acrosin and trypsin, was inhibited by benzamidine but not iodoacetamide. While all natural trypsin inhibitors tested inhibited acrosin, TSPE was not inhibited by ovomucoid from chicken or turkey egg white.
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PMID:Proteolytic enzymes in seminal plasma of domestic turkey (Meleagris gallopavo). 767 33

Plasma membrane proteins were extracted either from epididymal sperm after incubation with ampullary gland secretion or from uterine sperm derived from surgically treated males belonging to the following groups: TX, excision of all accessory sex glands (ASG); AGX, bilateral excision of ampullary glands; AG, excision of all ASG except ampullary glands; and SH, sham-operated. Total membrane protein, glycoprotein, and SDS-PAGE of individual polypeptide subunits were quantified. After incubation with ampullary gland secretion, both protein and glycoprotein concentrations of epididymal sperm membrane were increased. The protein profile was also significantly altered, with the removal of the 43- and 71-kD subunits and the addition of the 36- and 50-kD subunits. The in vitro results confirmed this proteolytic effect of ampullary gland and other ASG on the 43- and 71-kD subunits, despite a reduction in membrane protein concentration. Modification of the 17-, 20-, 25-, 28-, 56-, and 66-kD proteins were also observed. This report is the first demonstration that the ampullary gland is capable of modifying proteins on the sperm surface.
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PMID:Quantitative electrophoretic study of the modification of sperm plasma membrane by the ampullary gland in the golden hamster. 778 88

Previous studies from this laboratory have identified rat epididymal luminal fluid acid beta-D-galactosidase activity which also optimally hydrolyses a glycoprotein substrate at neutral pH [Skudlarek, Tulsiani and Orgebin-Crist (1992) Biochem. J. 286, 907-914]. We have now separated the luminal fluid beta-D-galactosidase into two molecular forms by ion-exchange chromatography on a column of DE-52. The separated enzyme activities were purified to an apparent homogeneity by molecular-sieve chromatography followed by affinity chromatography on a column of immobilized p-nitrophenyl beta-D-thiogalactopyranoside. The purified forms, when resolved by SDS/PAGE under reducing conditions, showed apparent molecular masses of 84 and 97 kDa. Kinetic studies, including a pH-dependent substrate preference and pH-dependent association/dissociation, disclosed no differences between these two forms. The two forms had identical N-terminal amino acid sequences. However, the 97 kDa form contained much more total carbohydrate and sialic acid than the 84 kDa form. The carbohydrate moieties in the two forms were assessed by comparing their size on SDS/PAGE before and after treatment with endo-enzymes. The removal of N-linked glycans by treatment with N-glycanase or endoglycosidase F generated de-N-glycosylated polypeptides of an apparent molecular mass of 70 kDa, and indicated that the two forms contained varying amounts of asparagine (N)-linked high mannose/hybrid-type and biantennary complex-type oligosaccharides. This result and the fact that the two molecular forms had identical N-terminal amino acid sequences indicated that the two forms probably have identical or very similar polypeptides. The potential role of the enzyme in modification of sperm plasma membrane (PM) glycoproteins was examined by resolving caput sperm PM proteins (before and after treatment in vitro of the membranes with the purified beta-D-galactosidase) on SDS/PAGE, followed by staining with peanut agglutinin (PNA), a lectin which preferentially binds to Gal beta 1,3GalNAc-linkages found in O-linked glycoproteins. The evidence presented in this report has indicated that a PNA-positive glycoprotein of an apparent molecular mass of 135-150 kDa present on the caput (but not cauda) sperm PM is degalactosylated by the digestion in vitro of the membranes with purified luminal fluid beta-D-galactosidase. This result suggests a possible role for the epididymal luminal fluid beta-D-galactosidases.
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PMID:Purification and characterization of two forms of beta-D-galactosidase from rat epididymal luminal fluid: evidence for their role in the modification of sperm plasma membrane glycoprotein(s). 782 52


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