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)

Glycoprotein dynamism in the mouse epididymis was studied by means ofhistoautoradiography after injection of L-fucose-1-3H. The label was detected, at thirty minutes p.i., in the area occupied by Golgi apparatus in the epithelial cells. At 4 h p.i. the label was already present inthe lumen of ductus epididymidis. At this time interval, the luminal labelling was highest in the initial segment of the epididymis and decreased against the more distal segments considerably. At ten days p.i. very high labelling was detected in the luminal contents in the terminal segment of the ductus epididymidis and in ductus deferens, the labelling in the proximal segments of the epididymis being much lower. These observations suggested a wave of labelled glycoprotein in epididymal plasma passing through the epididymis after a fucose pulse. Higher labelling was detected in so-called "clrial was seen in epididymal and uterine spermatozoa, mostly in sperm tail region.
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PMID:An autoradiographic study of macromolecular syntheses in the epithelium of the ductus epididymidis in the mouse. II. Incorporation of L-fucose-1-3H. 83 11

A 80 kDa human sperm antigen has been identified using the serum of an infertile woman having circulating antisperm antibodies. The antigen was then purified to homogeneity by gel permeation chromatography using HPLC (protein PAK-125 column) system and on FPLC (superose-12 column) system. The antigen was found to be a glycoprotein. The antigen was mainly localized in the postacrosomal region of the human sperm, while it was localized in the head region of the rat sperm as demonstrated by immunofluorescent staining. The presence of this antigen was also demonstrated in the human prostate and endometrium and in the rat testis; epididymis and the prostate by immunocytochemical staining. The purified protein upon active immunization in female rats caused infertility in 100 percent animals. While in male rats it caused infertility in 90 percent animals. On morphometric analysis of testicular tissue it was observed that there was no significant change in spermatogonia and spermatocytes, but significant decrease in spermatids and sperm number as well as daily sperm production in the immunized male rats. The epididymal spermatozoa were markedly reduced in number and were largely found to be agglutinated. The results suggest that 80 kDa human sperm antigen appears to be a suitable candidate for immunocontraception both in male and female.
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PMID:Antifertility effects in rats actively immunized with 80 kDa human semen glycoprotein. 129 24

The maturing goat epididymal spermatozoa were isolated from different segments of epididymis and these cells dispersed in a modified Ringer's solution, were incubated at 37 degrees C for 60 min to evaluate their autoagglutination efficacy. Distal corpus-epididymal spermatozoa specifically showed high order of head-to-head autoagglutination property whereas all other sperm cells did not show any detectable aggregation. The goat epididymal plasma has been shown to possess an anti-agglutinin that markedly inhibits sperm agglutination phenomenon and also dissociates the cells from the sperm clusters. Epididymal plasma is the most potent source of the anti-agglutinin which is a heat-stable specific glycoprotein. Like the autoagglutination phenomenon, the initiation of sperm forward progression also starts in the distal-corpus epididymis. The temporal correlation of these two events suggests that sperm autoagglutination may be a prerequisite for the induction of flagellar motility during the epididymal maturity of male gametes.
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PMID:Maturation-dependent goat epididymal sperm autoagglutination and its inhibition by a glycoprotein factor. 129 30

Impact of altered serum prolactin status on enzymes involved in glycoprotein metabolism in epididymal tissue of matured monkeys was studied. Hyperprolactinemia (ovine prolactin-250 micrograms/kg body weight/day for 30 days) significantly inhibited the specific activities of dolichylphosphate mannosyl transferase, dolichylphosphate glucosyl transferase and galactosyl transferase, in the epididymal tissues. However, it had an enhanced effect on epididymal glycosidases such as beta-galactosidase, beta-N-acetyl glucosaminidase, beta-N-acetyl galactosaminidase, alpha-mannosidase and alpha-L-fucosidase. Hypoprolactinemia (bromocriptine mesylate-1-mg/kg body weight/day for 30 days) on other hand had no significant effect on the specific activities of both, glycosyltransferases and glycosidases, in the epididymal tissues. The results suggest that hyperprolactinemia inhibits epididymal glycoprotein metabolism by impairing the incorporation of oligosaccharide units into proteins with enhanced degradation. This may have adverse effect on events leading to sperm maturation in epididymal environment.
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PMID:Role of prolactin on epididymal glycoprotein metabolism in matured monkeys, Macaca radiata: specific activities of glycosyltransferases and glycosidases. 129 32

Acidic epididymal glycoprotein (AEG) is an androgen-regulated, epididymal secretory protein assumed to be involved in sperm maturation. In the present study, we show that the mouse submandibular gland (SMG) expresses two genes designated Aeg-1 and Aeg-2. The nucleotide sequence of Aeg-1 cDNA clones was identical to that of epididymis-expressed Aeg cDNA clones, indicating that Aeg-1 is expressed in both epididymides and SMGs. The second, more abundant transcript, Aeg-2, had a sequence similar to, but distinct from, that of Aeg-1, and was not detectable in the epididymis. The level of Aeg-1 and Aeg-2 transcripts in the SMG was androgen-regulated and showed sexual dimorphism. In situ hybridization of SMG sections showed that Aeg-1 and Aeg-2 transcripts are produced by the cells of granular convoluted tubules. The C-terminal cysteine-rich region of the mouse AEG-2 molecule appears to have diverged faster than that of the mouse AEG-1 molecule, consistent with the idea that this region may play a role unique to the protein of the male reproductive system.
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PMID:Mouse submandibular glands express an androgen-regulated transcript encoding an acidic epididymal glycoprotein-like molecule. 130 83

A highly purified 15 kDa glycoprotein isolated from ejaculated spermatozoa was used to raise antisera in female rabbits. An indirect immunofluorescence technique was used to detect the antigen in the seminal vesicle tissue and on the acrosomes of ejaculated, native and capacitated, boar spermatozoa. No immunoreactivity was detected on cells of the seminiferous tubules (spermatogonia, spermatocytes, and spermatids), on spermatozoa in the ductus epididymis and in cells of the epididymal and testicular tissues. These observations support the view that the 15 kDa protein is produced in the seminal vesicle secretory epithelium, and is attached to the sperm plasma membrane during the exposure of spermatozoa to seminal vesicle compounds. The observations that the antigen remained on the acrosome of ejaculated spermatozoa after capacitation and blocked sperm-oocyte binding in vitro suggest that the antigen plays a role in sperm-egg interactions. The strong immunoreactivity exhibited by cumulus cells after incubation of antisera with the porcine egg surrounded by cumulus cells shows the possible importance of the 15 kDa glycoprotein for contact of spermatozoa with cells of the cumulus oophorus surrounding the egg.
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PMID:Binding of a 15 kDa glycoprotein from spermatozoa of boars to surface of zona pellucida and cumulus oophorus cells. 133 39

Several glycosidases, purified and characterized from mammalian tissues, have been shown to be optimally active under acidic conditions when p-nitrophenyl (PNP) or 4-methylumbelliferyl glycosides are used as substrates. Although high levels of the glycosidases are present in the epididymal lumen, their physiological role remains uncertain. To be functional, the glycosidases are expected to be enzymatically active at or near the physiological pH of luminal fluid. In this report, we demonstrate that the rat epididymal luminal fluid beta-D-galactosidase, optimally active toward PNP beta-D-galactoside at pH 3.5, shows maximum activity towards a glycoprotein substrate ([Gal-3H]fetuin) at neutral pH. Several lines of evidence, including immunoprecipitation studies using antibody to the acid beta-D-galactosidase, and substrate competition studies, indicate that PNP galactosidase and [3H]Gal galactosidase activities are caused by a single enzyme, and that the two substrates are probably cleaved by the same catalytic site(s). Competition studies with various disaccharides indicate that this enzyme is capable of cleaving a variety of galactose linkages found in both O- and N-linked oligosaccharides. Molecular-sieve column chromatography of the beta-D-galactosidase of luminal fluid under several conditions of buffer and pH show that, whereas the enzyme eluted as a tetramer (apparent M(r) 320,000) under acidic conditions (pH 3.5-4.3), only dimers and monomers (apparent M(r) 180,000 and 92,000 respectively) were observed in neutral conditions (pH 6.8). This aggregation/dissociation phenomenon is reversible. These studies indicate that beta-D-galactosidase is present in the luminal fluid in dissociated forms, and is therefore optimally active towards glycoprotein substrates at physiological pH. The potential role of the enzyme in modification of sperm surface glycoproteins is discussed.
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PMID:Rat epididymal luminal fluid acid beta-D-galactosidase optimally hydrolyses glycoprotein substrate at neutral pH. 141 50

A number of mammalian sperm plasma membrane antigens have been implicated as playing a functional role in sperm-egg interaction, by virtue of the fact that antibodies against these antigens interfere with fertilization. Two such mouse sperm plasma membrane antigens are M42, a 200/220 kD glycoprotein doublet, and M5, a 150-160 kD glycoprotein. We show that both of these antigens are concentrated on the posterior region of caudal epididymal and capacitated mouse sperm heads and are relatively diffusible, as determined by fluorescence recovery after photobleaching measurements (D = 3-8 x 10(-9) cm2/s with approximately 23% diffusing). Crosslinking of these antigens with bivalent antibodies causes them to redistribute into the anterior region (acrosomal crescent) of the sperm head. In contrast, we describe a third antigen, P220, which is also localized to the posterior region of the sperm head on caudal epididymal sperm but which exhibits very little diffusion and does not redistribute upon crosslinking. Bivalent anti-M42 blocks the ZP3-induced acrosome reaction. We have found that monovalent Fab fragments of anti-M42 do not block the ZP3-induced acrosome reaction, but that inhibition is restored by addition of a second antibody which crosslinks the Fabs. Thus, crosslinking is required for both inhibition of the acrosome reaction and redistribution. This suggests that redistribution of antigen away from the posterior region of the head may be part of the mechanism of inhibition of the ZP3-induced acrosome reaction.
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PMID:Protein dynamics in sperm membranes: implications for sperm function during gamete interaction. 141 94

Clusterin is a heterodimeric glycoprotein synthesized and secreted by rat Sertoli cells and epididymal epithelium. The goal of this study was to determine the presence of clusterin in the luminal fluid of the cauda epididymides and its association with the membranes of developing spermatozoa in the presence and absence of androgen. We have previously demonstrated by two-dimensional (2-D) Western blot probing for clusterin that in epididymal fluid the amounts of clusterin were: caput greater than corpus greater than cauda. Luminal fluid from cauda epididymides was collected from control and orchiectomized rats (6 and 12 days) and orchiectomized animals that received testosterone implants. Equal volumes of fluid were analyzed by 2-D Western blot probing for clusterin. Following orchiectomy, there was an increase in clusterin in the luminal fluid after 6 days and maximal amount after 12 days compared with control cauda fluid. Orchiectomized animals which received testosterone treatment showed levels of clusterin comparable to that of controls. Serum clusterin was detected in fluid of orchiectomized animals with and without testosterone. Western blots of cauda sperm membrane extracts of control animals and orchiectomized animals treated with testosterone had a very low level of epididymal clusterin, whereas extracts collected from orchiectomized animals revealed high levels of clusterin. We suggest that, in the normal animal, clusterin is secreted into the lumen of the proximal epididymis where it binds to the sperm membrane. In the distal epididymis, clusterin dissociates from sperm and is processed (proteolysis/endocytosis). We hypothesize that, in the absence of androgen, the processing and regulation of clusterin is disrupted.
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PMID:Clusterin (SGP-2) in epididymal luminal fluid and its association with epididymal spermatozoa in androgen-deprived rats. 151 50

A glycoprotein, designated SVS II, is secreted in an androgen-dependent manner from lateral prostate and seminal vesicles of the rat. The pI of the protein is 10.5 and it has a molecular mass of 49 kDa. F-actin isolated from skeletal and heart muscle is precipitated at a ratio of 2:1 by SVS II. Using a polyclonal rabbit antibody against SVS II, we found an immunoreaction at the head region of rat spermatozoa removed from the vas deferens. In addition, immunoreactive material was observed in the principal piece of the sperm tail in those spermatozoa. We have studied the distribution of SVS II-immunoreactive material in spermatozoa isolated from seminiferous tubules, proximal (efferent ductules), and distal (caudal epididymal duct) epididymis, both in sexually active and inactive rats and found a differential reactivity pattern. Immunoreactivity observed in the principal piece of the sperm tail develops only immediately before spermiation and does not change during the epididymal transit of the spermatozoa. Immunolabelling seen in the head portion is first observed in spermatozoa from proximal epididymis. Simultaneous with its appearance, rhodamine-labelled phalloidin, indicating the presence of F-actin, no longer binds to that region. While the immunoreaction of the sperm head is attributed to extrinsic SVS II, added to the sperm head in proximal epididymis, the immunoreactivity of the sperm tail seems to result from a cross reactive intrinsic sperm tail protein that achieves its final structure briefly prior to the onset of spermiation.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Localization of intrinsic and extrinsic SVS II immunoreactivity in rat spermatozoa. 151 73


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