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)

To dissect the process of mammalian sperm interaction with the egg at a molecular level, we have generated monoclonal antibodies (mAbs) to mature mouse sperm using syngeneic mouse testis as the immunogen. In this paper, we report upon three members of a mAb family, all of which displayed identical immunofluorescence patterns on cauda epididymal mouse sperm. Each of these mAbs, termed M42, M5, and M41, localized to a restricted region of plasma membrane overlying the acrosome. When tested for an effect on the fertilization process in vitro, two of the mAbs, M42 and M5, demonstrated significant inhibition. The inhibitory capacity was dependent upon the presence of the zona pellucida; neither M42 nor M5 was capable of blocking fertilization when zona pellucida-free mouse eggs were used. Identification of the antigens recognized by this group of mAbs was achieved by immunologic detection of sodium dodecyl sulfate-extracted sperm components separated via electrophoresis on 12% sodium dodecyl sulfate-polyacrylamide gels followed by transfer to nitrocellulose. M42, which blocked fertilization, recognized a high molecular weight cluster of bands with Mr of approximately 220,000 to 240,000. M5, which also prevented fertilization, specifically recognized a sperm component with subunit molecular weight of approximately 54,000. M41, which did not interfere with fertilization, did not interact with any high molecular weight components, but recognized components with Mr of approximately 60,000, 35,000, and 21,000. Taken together with the work presented in a companion paper (Saling, Irons, and Waibel, this issue), we have demonstrated that it is possible to describe particular cellular regions of mammalian sperm with respect not only to location and function, but also to the molecules that are candidates for a role in that function.
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PMID:Mouse sperm antigens that participate in fertilization. II. Inhibition of sperm penetration through the zona pellucida using monoclonal antibodies. 404 34

Young beef bulls (n = 27) were used in a trial to study the effect of dihydrostreptomycin sulfate (DHS) or oxytetracycline (OTC) hydrochloride on spermatogenesis, epididymal sperm maturation, and freezability of sperm. Nine of the bulls were given a 22 mg/kg dose of DHS twice, 12 hours between doses. Nine other bulls were treated with OTC--1 dose of 26.4 mg/kg of body weight, and then 6 more doses each of 17.6 mg/kg, ca 12 hours between doses. The remaining 9 bulls were nontreated controls. The treatment regimens with the 2 antibiotics were without effect on spermatogenesis. These treatments also were without effect on seminal pH, ejaculate volume, percentage of motile spermatozoa, rate of spermatozoal motility, or concentration of spermatozoa in ejaculates harvested on day 3 or 7 of the study (day 0 = 1st day of treatment). There was a treatment-by-day effect on spermatozoal concentration; the number of sperm per milliliter was markedly increased on day 3 for OTC-treated bulls. The increased spermatozoal concentration in the OTC-treated group was associated with an influence of the antibiotic on ejaculation. All bulls given this antibiotic ejaculated without palpable penile engorgement or erection on day 3. On day 7 the rate of spermatozoal motility was increased in the 2 treatment groups compared with the rate in the control bulls. Also on day 7, the percentage of motile spermatozoa was greater in the OTC-treated bulls than in the control or DHS-treated bulls.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effect of dihydrostreptomycin or oxytetracycline on reproductive capacity of bulls. 608 31

Plasma membranes from bovine epididymal spermatozoa possess both cAMP-independent and cAMP-dependent protein kinase activity. With the synthetic peptide, Leu-Arg-Arg-Ala-Ser-Leu-Gly as substrate, the basal activity of the membrane-associated protein kinase(s) was 0.1 nmol phosphate incorporated X min X mg protein. In the presence of 5 microM cAMP, the apparent activity was increased about twofold. The addition of Nonidet P-40 (0.05%) to the assay mixture increased protein kinase activity to 0.4 and 4.0 nmol phosphate incorporated X min X mg protein in the absence or presence of 5 microM cAMP, respectively. Both isozymes of the cAMP-dependent protein kinase were detected in detergent-solubilized membranes but 95% of the activity appeared as a Type II form based on DEAE-Sephacel chromatography. Several polypeptide components of the plasma membrane served as substrates for membrane-associated cAMP-dependent protein kinases, in vitro. In the absence of detergent, two cAMP-dependent phosphoproteins of 41,000 Mr and 60,000 Mr were detected by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. When 0.05% Nonidet P-40 was included in the assay mixture, a cAMP-dependent phosphoprotein of 43,000 Mr appeared. Two-dimensional polyacrylamide gel electrophoresis of membranes phosphorylated in the presence of 5 microM and 0.05% Nonidet P-40 revealed phosphoproteins of the following molecular weights/isoelectric points: 56,000/6.7, 56,000/6.9, 51,000/6.2, 42,000/5.9, 42,000/6.0, 38,000/6.1, 38,000/6.4, 14,000/7.2, 12,000/7.4 and a train of five polypeptides appearing at 14,000/5.4-6.0.
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PMID:Protein phosphorylation of plasma membranes from bovine epididymal spermatozoa. 608 45

Arylsulfatase A was extracted and purified from boar epididymal sperm acrosomes. Acrosomes were extracted by sonication in 50 mM Tris-maleate buffer containing 50 mM MgCl2, pH 6.1, followed by treatment with 50 mM Tris-maleate plus 0.2% Brij-35, pH 6.1. Purification of arylsulfatase A was performed with a three-step procedure consisting of centrifugation (85,000 X g), affinity chromatography with p-aminobenzamidine-Sepharose followed by chromatography on diethyaminoethyl (DEAE) Sephadex. The specific activity of the purified enzyme was 54 mumol/h per mg protein. The purified arylsulfatase did not contain any detectable acrosin or hyaluronidase activities. Sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis revealed a major band with an estimated molecular weight of 65,000 daltons. Properties of arylsulfatase A, determined by hydrolysis of p-nitrocatechol sulfate, indicated that the enzyme was inhibited 46% by 3.1 microM Ag+ and had a pH optimum of 4.2. Boar acrosomal arylsulfatase A dispersed the cumulus cells of ovulated hamster and rabbit eggs as well as those of follicular pig eggs. No effect of the enzyme on the zona pellucida or the oolemma was observed.
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PMID:Purification of boar acrosomal arylsulfatase A and possible role in the penetration of cumulus cells. 614 55

Steroid sulfotransferase activity has been assayed in cytosol extracts obtained from the male hamster reproductive tract. Dehydroisoandrosterone and desmosterol were used as substrates in the presence of phosphoadenosine phosphosulfate-35S as sulfate donor. No significant sulfotransferase activity was found in the testis. In the epididymis, a severalfold increase in activity was found in the tissue from the caput to the caudal regions. A lower but significant activity was detected in the vas deferens. The enzyme appears to be secreted into the luminal fluid while little activity is associated with the spermatozoa. This increase in activity along the epididymis is undoubtedly responsible for the accumulation of sterol sulfates reported previously. In view of the fact that sterol sulfates are potent and specific inhibitors of acrosin, as reported for the porcine and confirmed herein for hamster acrosin, the epididymal production of steroid and sterol sulfates may represent a protective mechanism against the premature release of proteolytic activity within the male reproductive tract.
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PMID:Distribution of steroid sulfotransferase in the male hamster reproductive tract. 624 Feb 84

A phosphoprotein phosphatase has been partially purified from rat epididymal fat pads by a procedure utilizing ammonium sulfate and ethanol precipitations and chromatography on DEAE-Sephadex A-50. The phosphatase was eluted from Sephadex G-75 columns with an apparent molecular weight of 28 000. The phosphoprotein phosphatase catalyzed the reversible deactivation of protein kinase activated chicken adipose tissue hormone-sensitive triglyceride lipase. Phosphatase activity measured with activated triglyceride lipase as substrate was completely dependent upon the presence of metal ions (Mg2+, Ca2+, or Mn2+) and was inhibited by inorganic phosphate and adenine nucleotides. The fat pad phosphatase increased the rate of activation of glycogen synthase in rat adipose tissue infranatant fractions from fed and 24-h fasted rats but had little or no effect on synthase activity in infranatant fractions from rats fasted for 48 h. Fasting had no effect on rat fat pad phosphatase activity measured with triglyceride lipase as substrate, but phosphatase activity was decreased in preparations from diabetic rats.
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PMID:Properties of a phosphoprotein phosphatase from rat epididymal fat pads: deactivation of hormone-sensitive triglyceride lipase and activation of glycogen synthase in adipose tissue. 624 77

Acetyl-CoA carboxylase phosphatase has been purified from the rat epididymal fat pad. The phosphatase occurs in a complex with the carboxylase. In the purification of the phosphatase, the high molecular weight complex was initially separated by sucrose gradient centrifugation, and the phosphatase was isolated from the complex by adjusting to 80% saturation with ethanol and by chromatography on Sephadex G-75. The molecular weight of the phosphatase is 71,000 as determined by sodium dodecyl sulfate gel electrophoresis and gel chromatography on Sephacryl-200 in the presence of 6 M urea. The Km for acetyl-CoA carboxylase and glycogen phosphorylase a are 1.5 microM and 37 microM, respectively. The phosphatase has a broad substrate specificity, being active toward glycogen synthase, 3-hydroxy-3-methylglutaryl-CoA reductase, phosphorylase a, phosphoprotamine, and p-nitrophenyl phosphate, in addition to acetyl-CoA carboxylase from fat tissue and liver. Acetyl-CoA carboxylase inhibits the dephosphorylation of phosphoprotamine, indicating that the same activity is responsible for dephosphorylating both substrates. The phosphatase requires no metal ion for activity and is not inhibited by the rat liver phosphorylase phosphatase inhibitor protein. The significance of these findings is discussed in relation to the regulation of acetyl-CoA carboxylase, and the phosphatase is compared to other phosphoprotein phosphatases.
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PMID:Purification and properties of acetyl-CoA carboxylase phosphatase. 625 18

A protein in rat liver cytosol whose phosphorylation was regulated by hydrocortisone administration in vivo was tentatively identified as the regulatory subunit of a cAMP-dependent protein kinase. Evidence that this protein, whose phosphorylation was regulated by steroid and cyclic AMP, is the regulatory subunit of type-II cAMP-dependent protein kinase included: (a) co-purification of the steroid/cAMP-regulated protein and the regulatory subunit during DEAE-cellulose, Sepharose 4B, and hydroxylapatite column chromatography, (b) co-migration of the two proteins on dodecyl sulfate/polyacrylamide slab gels during the various steps of purification, (c) specific adsorption of the two proteins onto 8(6-aminohexylamino)-cAMP--Sepharose 4B, and (d) a similar pattern of distribution of the two proteins in various subcellular fractions prepared from rat liver homogenate. By each of these criteria, it was found that the steroid/cAMP-regulated protein present in rat liver cytosol behaved identically with the regulatory subunit of type-II cAMP-dependent protein kinase in that tissue. Results qualitatively similar to those obtained in the study of the effect of hydrocortisone on rat liver were also obtained in studies of the effects of other steroid hormones on other target tissues in the rat, including uterus (17 beta-estradiol), ventral prostate and seminal vesicle (testosterone), and epididymal fat pad (hydrocortisone). The tentative identification of the steroid/cAMP-regulated protein as the regulatory subunit of the type-II cAMP-dependent protein kinase in the cytosol of several tissues indicates that autophosphorylation of the regulatory subunit of type-II protein kinase may be regulated by the steroid hormones. The fact that three different classes of steroid hormones appear to affect the phosphorylation of the regulatory subunit of type-II cAMP-dependent protein kinase in their target tissues raises the possibility that this common biochemical action may play an important role in the mechanism of steroid hormone action. It is also possible that this effect of the steroid hormones may provide a molecular basis for some of the known physiological interactions of the steroid hormones with those hormones that act through using cAMP as a second messenger.
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PMID:Steroid hormones may regulate autophosphorylation of adenosine-3',5'-monophosphate-dependent protein kinase in target tissues. 626 19

An inhibitor (inhibitor-1) of phosphorylase a phosphatase has been identified in rat epididymal fat pads. This heat-stable, acid-soluble protein only exhibits phosphatase inhibitory activity when it itself is phosphorylated. Inhibitor-1 in rat adipose tissue migrates at 32,000 Da on sodium dodecyl sulfate-polyacrylamide gels, and at 64,000 Da on gel filtration. Exposure of fat pads to insulin (1 milliunit/ml) resulted in a 50% decrease in inhibitor-1 activity, compared to control (p less than 0.001). Isoproterenol (10(-6) M) caused a 25% increase in inhibitor-1 activity (p less than 0.05). Electrophoresis of heat-stable proteins prepared from hormone-treated 32P-labeled fat cells showed that insulin caused a dephosphorylation of the 32,000 Da phosphoprotein by 30% (p less than 0.01), whereas isoproterenol stimulated 32P incorporation in this protein by 35% compared to control (p less than 0.05). Thus, insulin appears to dephosphorylate and inactivate inhibitor-1, and might thereby result in an increase of protein phosphatase activity. Insulin regulation of inhibitor-1 is a mechanism which may underlie other of insulin's effects in adipose tissue, such as the activation of glycogen synthase.
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PMID:Hormonal regulation of protein dephosphorylation. Identification and hormonal regulation of protein phosphatase inhibitor-1 in rat adipose tissue. 634 43

Sequential treatment of the chicken liver fatty acid synthetase by trypsin and subtilisin cleaved the Mr 267,000 subunit to 6-8 polypeptides, ranging in molecular weights from 15,000 to 94,000. Fractionation of the digest by ammonium sulfate and chromatography on a Procion Red HE3B affinity column permitted the isolation of a polypeptide (Mr = 94,000) containing the beta-ketoacyl reductase activity but no other partial activities normally associated with the synthetase. The specific activity of the beta-ketoacyl reductase increased 2 to 3 times in this fraction, an increase that is within the expected range based on relative molecular weight. The kinetic parameters of this fraction towards NADPH and N-acetyl-S-acetoacetyl cysteamine were essentially the same as the beta-ketoacyl reductase component of the intact synthetase. However, the purified fragment did not catalyze the reduction of acetoacetyl-S-CoA derivative, a substrate that is readily reduced by the intact synthetase. Fluorescence measurements with etheno-NADP+ indicate the binding of about 1 mol of NADP+/94,000 daltons, a value which is in agreement with the results obtained from fluorescence measurements with NADPH and the binding of a radiolabeled photoaffinity analog of NADP+. Phenylglyoxal inhibits the beta-ketoacyl reductase activity of either the intact synthetase or the isolated fragment, suggesting the involvement of an essential arginine at or near the active site. Another fragment (Mr 36,000) containing beta-ketoacyl reductase activity was isolated from the synthetase after kallikrein/subtilisin double digestion. Previous mapping studies had shown that this fragment lies adjacent to the COOH-terminal thioesterase domain and overlaps the tryptic Mr 94,000 peptide by approximately 21 daltons. This fragment, but not the Mr 94,000 fragment, was found to contain the phosphopantetheine prosthetic group, indicating that the acyl carrier protein moiety is located in the 15,000-dalton segment that separates the beta-ketoacyl reductase from the thioesterase domain.
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PMID:The architecture of the animal fatty acid synthetase. III. Isolation and characterization of beta-ketoacyl reductase. 636 Oct 31


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