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)

Effect of starvation on tissue radioactivity of 14C-DDT was examined in mice 8 days after its single injection. Animals were completely fasted and given barium sulfate by gastric intubation for the last 3 days. The findings obtained from starved mice were as follows: 1) loss of body weight, 2) decrease in organ weight of epedidymal fat and liver, 3) reduction in lipid content of whole body as well as of epididymal fat, 4) a marked elevation of DDT levels in tissues except muscle, and 5) occasional neurotoxidc signs characterized by tremors and convulsions. Excretion of DDT-related metabolites was not changed by starvation. Analysis of metabolic producets of 14C-DDT using thin-layer radiochromatography revealed that there was little or no significant difference between control and starved mice in the metabolic pattern of DDT-related compounds in the tissues and excreta. It was assumed the DDT-ingested animals with dietary energy restriction had a subsequent risk of toxicity resulted from redistribution of DDT, but not from alteration in excretion or metabolism.
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PMID:Effect of starvation on excretion, distribution and metabolism of DDT in mice. 88 38

An androgen affinity column was synthesized by covalently linking 3-oxo-17beta-hydroxy-5alpha-androstan-17alpha-(6-hexanoic acid) to cyanogen bromide activated Sepharose through a dipropyldiamine side arm. This column was designed to recover androphilic proteins from homogenates rich in nonspecific esterases. An extract of rat epididymis was adsorbed on the affinity column after partial purification by ammonium sulfate precipitation. The column was washed with 1 M KCl and the androgen binding protein eluted with 17beta-hydroxy-5alpha-androstan-3-one resulting in a 1,100-fold increase in specific activity. This protein had the same mobility on polyacrylamide gels and the same estimated molecular weight (135,000 daltons by gel filtration) as androgen binding protein in the original extract. By contrast, electrophoresis on sodium dodecyl sulfate containing gels yielded 2 bands with estimated molecular weights of 42,000 and 47,000 daltons. These observations are consistent with a subunit structure for rat epididymal androgen binding protein.
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PMID:A novel affinity column for isolation of androgen binding protein from rat epididymis. 89 61

Swelling of the spermatozoan nucleus and decondensation of the chromatim occur soon after penetration of spermatozoa into the egg cytoplasm. This decondensation was duplicated in vitro by incubating pre-ejaculatory ram, rabbit and bovine spermatozoa and also stored post-ejaculatory bovine spermatozoa in 1% sodium dodecyl sulfate and 2.0 mM dithiothreitol. Spermatozoa obtained from the testis and epididymal caput, corpus and cauda showed a progressive resistance to nuclear decondensation, while no change was evident in the decondensation time of spermatozoa obtained from the epididymal cauda, vas deferens and ejaculated semen. There was also a significant increase in decondensation time after the spermatozoa had been stored in vitro at 25 degrees C. This increased resistance to nuclear decondensation in the in vitro stored spermatozoa, reflecting an increase in cross-linking within the spermatozoan histones by formation of disulfide bonds, may account for part of the increased embryonic mortality observed when spermatozoa are stored in vitro prior to insemination.
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PMID:Nuclear decondensation of mammalian spermatozoa: changes during maturation and in vitro storage. 92 69

The ability to form androgen conjugates and the hormone dependency of the conjugating enzymes have been studied in the rat epididymis. Following the in vitro incubation of 3H-testosterone with epididymal slices from intact and castrated rats, the radioactivity recovered was partitioned between water and ether. Examination of the water soluble radioactivity demonstrated the presence of glucuronides and sulfates. The total radioactivity in the conjugate fraction was the same for both intact and castrated animals. However, castrated rats showed a 3-fold increase in the glucuronide fraction with a corresponding decrease in the formation of sulfates. Characterization of the ether soluble radioactivity after solvolysis of the conjugate fraction from castrated animals, showed DHT (17beta-hydroxy-5alpha-androstan-3-one) and 3alpha-diol (5alpha-andro-stane-3alpha, 17beta-diol) to be the main metabolites. After beta-glucuronidase hydrolysis of the same, only 3alpha-diol could be demonstrated at a significant level, although traces of DHT and delta16 compounds were present. Corresponding hydrolysis of the water phase from incubation of epididymis from intact rats, demonstrated a marked quantitative difference. Here approximately 40% of the conjugated aglycones consisted of delta16 compounds, whilst only about 12% was comprised of 3alpha-diol. The preferential conjugation of DHT and 3alpha-diol to a sulfate radical was demonstrated in both intact and castrated rats. Since the conjugated delta16 compounds were detected only in the epididymis from intact animals, it is possible that these are formed by the spermatozoa.
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PMID:Androgen metabolism by rat epididymis. 4. The formation of conjugates. 94 Nov 82

The incorporation of radioactivity into various cells in the sequence of spermatogenesis was measured by preparing highly purified spermatozoan nuclei from the cauda epididymidis of mice at daily intervals after injection of (3H)thymidine. The stages of differentiation of these sperm at the time of thymidine administration were calculated from the kinetics of spermatogenesis. The procedure for purification of sperm nuclei included sonication, mechanical shearing, and treatment with trypsin, DNase, Triton X-100, 2M NaC1, and sodium dodecyl sulfate. DNA was isolated from these nuclei by treatment with dithiothreitol and pronase, followed by phenol extraction and ethanol precipitation. The levels of radioactivity in the epididymal sperm head preparations were low (less than 13 dpm/mouse) for 27 days after injection, and then rose dramatically to over 4 times 104 dpm/mouse. Further experiments demonstrated that the 11 dpm of 3H radioactivity contained in sperm heads at 21 or 26 days after injection of (3H)TdR was significantly above background and contamination levels from other cells or other sources. Most of the radioactivity was in the sperm DNA and represented incorporation of tritium from (3H)TdR into the nuclear DNA of meiotic cells at 0.002 percent of the rate of incorporation into S-phase cells. Little, if any, (3H)TdR was incorporation into the DNA of spermatids. The levels of DNA synthesis during the meiotic prophase in the mouse appear to be much lower than those reported for other organisms.
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PMID:Meiotic DNA synthesis during mouse spermatogenesis. 110 31

1. In the present study, we isolated the two forms of proacrosin from acid extracts (pH 3.0) of cauda epididymal bovine spermatozoa by ammonium sulfate fractionation, gel filtration on Sephadex G-150 and affinity chromatography on Concanavalin A Sepharose 4B. The overall purification was 13-fold with respect to crude acid acrosomal extract. 2. The apparent molecular weight of the proacrosins determined by SDS-PAGE were 44,000 and 38,000. Both forms have proteinase activity on gelatin-SDS-polyacrylamide gel electrophoretic zymography. 3. The M(r) = 38,000 component was isolated by reverse phase HPLC. Thirty-nine amino acid residues at the N-terminus have about 72 and 77% sequence similarity with boar and human proacrosin, respectively. 4. The amino acid sequence of 14 amino acids at the N-terminus of the high molecular weight component (M(r) = 44,000) was determined after electroblotting on a polyvinylidene difluoride membrane. This portion of the molecule is identical with that of the low molecular weight component. 5. Proacrosin autoactivation followed the sigmoidal activation curve.
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PMID:Bovine proacrosin from cauda epididymal sperm: purification, characterization and partial sequencing at N-terminus. 147 7

A 25-kDa epididymal secretory protein (MEP 9), isolated from mouse epididymal fluid, has recently been characterized in our laboratory [Rankin et al., Biol Reprod 1992; 46:747-766]. The polyclonal antibody raised against this protein was found to recognize a 25-kDa component in epididymal fluid and testicular extract. The 25-kDa testicular antigen (MTP) was purified by means of ammonium sulfate precipitation, gel filtration, and anion-exchange chromatography; MTP was found to be similar to MEP 9 in several properties including molecular mass (25 kDa), isoelectric point (pI 6.0), and immunoreactivity when the proteins were resolved in the presence of SDS (one-dimensional and two-dimensional PAGE). However, when the proteins were resolved under non-denaturing conditions, MTP showed strong immunoreactivity while MEP 9 did not. This observation suggests that although the 25-kDa antigens from the epididymal fluid and testicular extract are quite similar, they may have different immunological conformations. When analyzed for amino acid composition and partial amino acid sequence, the testicular antigen showed substantial homology (> 80%) with a phosphatidylethanolamine-binding protein characterized from bovine brain. MTP also showed phosphatidylethanolamine-binding activity (Kd = 1.95 x 10(-5) M, Bmax = 1.86 nmol/micrograms MTP), suggesting that the mouse 25-kDa protein is a member of the phospholipid-binding protein family and may have a role in lipid metabolism during sperm maturation.
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PMID:Isolation and characterization of a 25-kilodalton protein from mouse testis: sequence homology with a phospholipid-binding protein. 147 9

We identified a rat sperm flagellar surface antigen using an IgG1 monoclonal antibody (MC31) against rat epididymal sperm. Avidin-biotin-peroxidase immunohistochemistry demonstrated that the antigen was first expressed in the cytoplasm of early primary spermatocytes, then gradually became restricted to the principal piece of the sperm flagellum during spermatogenesis. However, when the sperm reached the corpus epididymidis, the antigen was expressed on the surface of both the principal piece and the midpiece of the flagellum. The epithelial cells of the epididymis were not stained with MC31. Immunogold electron microscopy showed that the antigen was present on the surface of the sperm flagellar plasma membrane. Immunoblotting of Triton X-100 extracts of epididymal sperm after one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) under nonreducing conditions demonstrated that MC31 detected a major antigen of 26,000-28,000 daltons (26-28K). Two-dimensional isoelectric focusing and SDS-PAGE indicated that the 26-28K antigen had an isoelectric focusing point (pl) of 5.8-5.3; minor antigens were also detected from 26K (pl 5.8) to 35K (pl 5.0). These results indicate that the antigen recognized by MC31 is an acidic 26-35K protein that originates in the testis, is integrated into the sperm flagellar plasma membrane of the principal piece during spermatogenesis, and then is expressed on the entire flagellar surface during epididymal transit.
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PMID:A rat sperm flagellar surface antigen that originates in the testis and is expressed on the flagellar surface during epididymal transit. 149 89

Ultraviolet (UV)-cross-linking and sodium dodecyl sulfate(SDS) polyacrylamide gel electrophoretic (PAGE) analysis were used to identify proteins of nuclear and cytosolic (S100) origin that specifically bind to an in vitro transcribed mRNA sequence for protein D. The coding region of the protein D cDNA was subcloned, in vitro transcribed to [32P]RNA, and incubated with nuclear and cytosolic extracts of enzymatically dispersed epididymal cells. As revealed by UV-cross-linking and SDS-PAGE analysis, two proteins exhibiting a molecular weight mass of approximately 2.5 and approximately 35 Kd that specifically recognize and bind to the in vitro transcribed mRNA sequence for protein D. Our findings suggest that the regulation of protein D gene expression in the rat epididymis may involve novel RNA-binding proteins.
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PMID:Identification of novel RNA-binding proteins that interact in the coding region of protein D sense RNA in vitro. 152 Mar 14

Anion transport inhibitors, such as SITS (4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid) and heparin, inhibit reversibly the bicarbonate-sensitive adenylylcyclase of porcine sperm plasma membrane. In the light of this, SITS- and heparin-affinity chromatographies were applied in order to purify sperm adenylylcyclase. SITS-Affi-Gel 102 binds proteins extracted from the porcine cauda epididymal sperm plasma membrane by Lubrol-PX, more selectively than heparin-agarose. However, recovery of adenylylcyclase activity is higher when heparin-agarose is used. The hormone-sensitive liver adenylylcyclase, which is less sensitive to bicarbonate than sperm enzyme, has less affinity for these affinity resins than sperm enzyme. Adenylylcyclase can be purified to apparent homogeneity on two-dimensional gel electrophoresis (isoelectric focusing/sodium dodecyl sulfate-polyacrylamide gel electrophoresis) from the Lubrol-PX extract of the purified sperm plasma membrane by using SITS-affinity chromatography at the first step of the purification followed by preparative isoelectric focusing and gel filtration. The molecular weight and pI of the purified enzyme are 46,300 and 6.9, respectively. The purified enzyme activity is highly dependent on Mn2+. Bicarbonate activates even the purified enzyme both by decreasing Km and by increasing Vmax.
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PMID:Purification of bicarbonate-sensitive sperm adenylylcyclase by 4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid-affinity chromatography. 165 24


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