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)

The 600-MHz proton spectrum of dethiobiotin (prepared from d-biotin with Raney nickel) was measured in order to gain information pertaining to its stereochemical homogeneity. The spectrum demonstrated clearly that the material is a 6:1 mixture of two stereoisomers. The cis compound, corresponding to the stereochemistry of d-biotin, is the major isomer. Two biotinyl- and two dethiobiotinylinsulins were prepared in which the distance between the biotins and insulin was varied by interposition of spacer arms. The synthesis of these compounds involved repeated N-hydroxysuccinimido ester condensations. Biotin N-hydroxysuccinimido ester, dethiobiotin N-hydroxysuccinimido ester, 6-aminohexanoic acid, and N-[3-[(3-aminopropyl)carboxyamino]-propyl]succinamic acid N-tert-butyl ester served as the building blocks for the spacers. The latter compound was prepared from N-[3-[(3-aminopropyl)amino]propyl]succinamic acid sulfate by the use of a selective amino-protecting method based on the differential stability toward acid of citraconyl and tert-butoxycarbonyl amino-protecting groups. The structure of N-[3-[(3-aminopropyl)amino]propyl]succinamic acid sulfate was established unequivocally by X-ray diffraction. The attachment of the biotinylated spacers to the insulin was exclusively at the N alpha, B1 position. Homogeneity of the final products as well as of the intermediates used in their synthesis was established by thin-layer chromatography, by high-pressure liquid chromatography, and in most instances by elemental analysis. The ratio of 6-aminohexanoic acid to lysine in hydrolysates of the insulin derivatives was in agreement with theory. The insulin derivatives were required for a study on the effect of avidin on their ability to interact with insulin receptors on rat epididymal adipocytes, which is described in the accompanying paper.
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PMID:Syntheses of biotinylated and dethiobiotinylated insulins. 638 May 70

One protein in canine seminal plasma accounts for over 90% of the total protein and is present at the high concentration of approximately 10 mg/ml. We demonstrate that this predominant protein is a proteolytic enzyme. The enzyme has been purified and migrates as a single symmetrical peak of apparent molecular mass of 29,000 daltons on a column of Sephadex G-75 and as a single band of approximately 30,000 daltons when analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under nonreducing conditions. Under reducing conditions, the enzyme dissociates into subunits of 15,000 and 12,000-14,000 daltons. The 15,000-dalton subunit contains the enzyme active site as determined by labeling with [3H]diisopropyl fluorophosphate. The enzyme hydrolyzed the synthetic ester substrates N alpha-benzoyl-L-arginine ethyl ester and N alpha-tosyl-L-arginine methyl ester with maximum specific activities at 25 degrees C of 105 mumol/min/mg and 33 mumol/min/mg, and Km values of 7.4 and 9.1 mM, respectively. The enzyme exhibited a pH optimum of 8.0. The metal ions, Cu2+, Zn2+, Cd2+, and Co2+ were reversible inhibitors and diisopropyl fluorophosphate and phenylmethanesulfonyl fluoride irreversible inhibitors of enzymatic activity. By immunofluorescence, the enzyme can be detected on the tail and postacrosomal regions of washed ejaculated canine sperm, but it is absent from epididymal sperm.
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PMID:The predominant protein of canine seminal plasma is an enzyme. 638

Bovine epididymal spermatozoa were incubated for 22 h in a modified Tyrode's medium. The percentages of sperm exhibiting an acrosome reaction were determined morphologically after fixing and staining specimens. The addition of chondroitin sulfate A (CS-A) significantly increased the incidence of acrosome reaction. When observed by electron microscopy, acrosome-reacted sperm had undergone vesiculation of the plasma and outer acrosomal membranes. Sperm incubated in the presence of CS-A demonstrated a significantly higher incidence of vesiculation when compared to the controls. Additionally, rates of in vitro fertilization of bovine oocytes were significantly elevated when sperm and ova were exposed to CS-A. These results suggest that glycosaminoglycans in the female reproductive tract may be responsible for some of the biochemical changes associated with fertilization, and a light microscope procedure can be used to assess occurrence of the acrosome reaction.
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PMID:Chondroitin sulfate facilitates an acrosome reaction in bovine spermatozoa as evidenced by light microscopy, electron microscopy and in vitro fertilization. 640 17

Washed ejaculated boar sperm and sperm from the cauda epididymis bind to the zona pellucida of fixed porcine eggs in large numbers. Sperm incubated in the presence of dextran sulfate (8 K daltons or 500 K daltons) or fucoidan and then washed no longer bind to eggs. Other acid carbohydrates (heparin, chondroitin sulfates, inositol hexasulfate, carboxymethylcellulose) fail to block sperm-egg binding even when added directly to sperm-egg suspensions. Seminal plasma and the seminal vesicle secretion contain basic proteins which bind tightly to sperm and bind reversibly to eggs preventing sperm from binding to eggs. When dextran sulfate or fucoidan are mixed with the vesicular secretion, from which seminal plasma basic proteins originate (Hunt et al., '83), the secretion loses the capacity to prevent sperm from binding to eggs; this suggests that seminal vesicle proteins can bind to the same site on zonae as do sperm and thus seminal plasma may modify sperm-egg interactions. Corpus and cauda epididymal sperm also bind in large numbers to the zona pellucida of isolated eggs but high concentrations of caput sperm, which exhibit high motility in the presence of caffeine, bind only in few numbers. Thus a component that enhances sperm-zona binding is apparently formed on the plasma membranes of uncapacitated sperm during passage through the epididymis. This finding, and an earlier observation that antibodies raised against uncapacitated sperm plasma membranes block sperm-egg binding in vivo (Peterson et al., '83) suggest that this component may be involved in sperm zona interaction in vivo.
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PMID:Evidence for specific binding of uncapacitated boar spermatozoa to porcine zonae pellucidae in vitro. 647 Jun 46

Three radiolabeling procedures were applied to ram spermatozoa obtained at three different stages of posttesticular development: on leaving the testis (testicular sperm); after epididymal transit (cauda epididymal sperm); and after exposure to accessory sex gland secretions (ejaculated sperm). The washed spermatozoa were subjected to three radiolabeling treatments: 1) galactose oxidase and sodium boro [3H]hydride (galactosyl and galactosaminyl residues); 2) sodium metaperiodate and NaBH4 (sialyl residues); and 3) chloroglycoluril and Na125 I (tyrosyl residues). High resolution sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoretic analysis of the surface radiolabeling patterns confirms earlier studies in demonstrating an overall shift in the predominant labeled glycoproteins from the zone 78-115 kd in testicular spermatozoa to relatively low molecular weights of between 15 and 95 kd in cauda epididymal or ejaculated spermatozoa. Labeling procedures specific for glycoproteins and sialoglycoproteins revealed additional complexities in the surface transformation patterns of ram spermatozoa and suggest that cauda epididymal spermatozoa exposed to accessory sex gland secretions adsorb or produce a component of high molecular weight (approx. 350 kd).
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PMID:Surface glycoprotein changes in ram spermatozoa during epididymal maturation. 662 54

Whether diminished or augmented behavioral effects are observed after repeated amphetamine administration may reflect the relative balance between tolerance and drug cumulation. To investigate this, we measured the distribution of d-amphetamine in various tissues and its effects on performance of a conditioned behavior after acute or chronic treatment. Rats trained to lever press under a fixed ratio 5 schedule for food-reinforcement were tested daily for 4 min epochs in each of 6 consecutive hours. After responding was stable, animals were injected for 16 days with saline or 1.0, 2.5 or 5.0 mg 3H-d-amphetamine sulfate/kg IP 15 min before the second daily behavioral epoch. On the 17th day, animals which had been receiving 3H-d-amphetamine were given their usual dose and those which had been receiving saline were given one of the doses of 3H-d-amphetamine; all animals were decapitated approximately 2 1/4 hours after this final injection, immediately after the 4th behavioral epoch. Brain, heart, muscle, epididymal fat, and kidney were removed for subsequent analysis of unchanged 3H-d-amphetamine. The experiment was carried out in two phases, 3 1/2 months apart, which inadvertently resulted in shipment of rats from different buildings on the supplier's campus. Acute treatment produced dose-related effects on operant responding, the lowest dose increasing responding and the highest dose suppressing it. Chronic injection of the highest dose of d-amphetamine resulted in significant attenuation of its acute suppressant effect. Additionally, chronic treatment suppressed responding of rats 23 1/4 hours after injection (i.e., before the subsequent daily injection). Tissue levels of d-amphetamine were dose related and d-amphetamine cumulated after chronic treatment with the highest dose. When d-amphetamine was administered acutely, the behavioural effect immediately before decapitation was highly correlated with the concentration of d-amphetamine in brain and in heart. This was not the case after chronic treatment, since rats given the higher doses showed less behavioural effect than would have been predicted from the concentrations of d-amphetamine in their tissues. Besides evidence of tolerance and cumulation of drug in one or more tissues, a significant phase or colony difference emerged, which could have been due to seasonal or other factors. Additional, different experiments, performed concurrently on a new shipment of rats from each colony, allowed us to conclude that the original observations of phase differences were not due to seasonal differences or chance.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Amphetamine cumulation and tolerance development: concurrent and opposing phenomena. 670 76

In Vitro binding and some binding parameters of the glycosaminoglycan heparin to viable epididymal or ejaculated bull spermatozoa, ejaculated rabbit spermatozoa, and frozen-thawed rhesus monkey spermatozoa were investigated. Nonspecific binding was affected only by the concentration of 3H-heparin, whereas specific binding was saturable, reversible, and dependent on the pH, temperature, and calcium concentration of the incubation medium. Magnesium concentration dependence was observed in the presence of calcium but could not be detected in the absence of calcium. Bound 3H-heparin was displaced by several orders of magnitude greater concentrations of chondroitin sulfate. Scatchard plot analysis suggested multiple binding affinities for 3H-heparin to spermatozoa. 3H-heparin was shown to bind to sperm heads and flagella. Fluorescein-labeled heparin bound to acrosomal, postacrosomal, and flagellar membranes. It was concluded that the specific binding of heparin involved a proteinaceous component on, or intercalated with, spermatozoal membranes. Thus, glycosaminoglycans present in the female reproductive tract may contribute to sperm capacitation and enhance the likelihood of successful fertilization in mammals.
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PMID:Specific binding of the glycosaminoglycan 3H-heparin to bull, monkey, and rabbit spermatozoa in vitro. 671 57

Treatment of caput or cauda epididymal rat sperm with a low concentration (0.05%) of the cationic detergent cetyltrimethylammonium bromide and 30 mM 2-mercaptoethanol solubilized most of the sperm structures except for the sperm head and the outer dense fiber-connecting piece complex. The latter were purified, and about 10% of these complexes are formed by nine fibers attached to the connecting piece. Of these fibers, two are shorter than the other seven and presumably correspond to fibers 3 and 8 (Fawcett, D.W. (1975) Dev. Biol. 44, 394-436). Electron microscopy confirmed the purity of the isolated outer dense fibers and revealed their characteristic irregular cross-sectional shape. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate showed six major polypeptides (Mr = 87,000, 30,400, 26,000, 18,400, 13,000, and 11,500) with a high content of serine, aspartic and glutamic acids, proline, cysteine, leucine, and tyrosine. Furthermore, several lines of evidence indicate a close structural relationship between the components of 30,400 and 26,000 Da. The six major components of the fibers are phosphorylated at serine residues. These results indicate that the major components of rat sperm outer dense fibers are a unique family of phosphoproteins.
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PMID:Polypeptide composition of rat sperm outer dense fibers. A simple procedure to isolate the fibrillar complex. 671 81

Utilizing hybridoma technology and highly purified acrosome stabilizing factor (ASF), six monoclonal antibodies (mAbs) specific for ASF were produced and characterized. Specificity and binding properties of each clone were examined by immunoperoxidase labeling of electrophoretic blots of rabbit serum, seminal plasma, cauda epididymal fluid and vasectomized seminal plasma separated on native and sodium dodecyl sulfate (SDS)-polyacrylamide gels. All mAbs recognize ASF in seminal plasma and cauda epididymal fluid but do not bind components in serum or vasectomized seminal plasma. Purification of ASF by affinity chromatography utilizing the mAbs, has shortened the 6-day isolation procedure for ASF used previously to less than 2 h and has increased the yield from 2 micrograms to 300 micrograms of ASF obtained per ml of seminal plasma. Three mAbs were used in conjunction with Cleveland digest with Staphylococcus aureus V8 protease, SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoperoxidase labeling of Western Blots, to identify peptides containing specific determinants recognized by each mAb. At least five separate determinants were recognized by the six mAbs. The sensitivity of the Western blotting technique in conjunction with the specificity of the mAbs was exploited to detect polymeric forms of ASF in seminal plasma and cauda epididymal fluid. ASF is shown to be a 360-kd dimer consisting of two identical 180-kd monomers. Tools are now available to develop sensitive qualitative and quantitative assays for ASF, thus providing rapid, extremely sensitive methods for evaluating experiments designed to probe the molecular mechanism of capacitation.
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PMID:Production and characterization of monoclonal antibodies to the sperm acrosome stabilizing factor (ASF): utilization for purification and molecular analysis of ASF. 672 44

Sperm surface antigens were prepared by detergent extraction (Hyamine-Triton, Rohm and Haas Co., Philadelphia, PA) of spermatozoa from rhesus monkeys. Heterologous antisera against the extracts were produced in female New Zealand White (NZW) rabbits by hyperimmunization. The antiserum was absorbed initially with sperm-free monkey seminal plasma and then with lyophilized tissue homogenates of liver, kidney, spleen, and pancreas from male rhesus monkeys. The unabsorbed antiserum produced at least three precipitin lines against detergent extract in double immunodiffusion tests and possessed sperm immobilization and sperm agglutination antibody activity. The absorbed antiserum showed one precipitin line against the detergent extract and retained sperm agglutination antibody activity only. The sperm agglutination antibody in the absorbed antiserum was completely removed by either epididymal or washed ejaculated rhesus monkey spermatozoa. The same results were obtained with ammonium-sulfate-precipitated immunoglobulin preparations. Immunoelectrophoresis revealed only one precipitation line with the absorbed immunoglobulin preparation. It is concluded that Hyamine-Triton extract of rhesus monkey spermatozoa contains a component which can be characterized as sperm-specific by immunoabsorption techniques and is apparently associated with sperm agglutination but not with immobilization.
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PMID:Sperm specific antigen(s) in detergent extract of rhesus monkey spermatozoa. 680 78


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