Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.2.1.36 (hyaluronidase)
4,606 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hyaluronic acid, a major component of the extracellular matrix, plays an important role in the regulation of different cellular processes, e.g., locomotion, cell-cell interaction during morphogenesis, and differentiation. Distribution of hyaluronic acid with respect to the role of sperm hyaluronidase in sperm penetration and gamete interaction is well established. In order to elucidate this mechanism, in our current study we have identified and demonstrated, for the first time, the presence of a 68-kDa cell surface hyaluronic acid binding glycoprotein (HABP) in spermatozoa of different species (rat, mice, bull, and human) by immunoblot analysis and indirect immunofluorescence using the polyclonal antibodies raised against purified HABP. Furthermore, we were able to demonstrate a differential distribution of 68-kDa HA binding protein on the sperm head, midpiece, and tail of different species. To identify its role in sperm function, we observed its declining pattern during epididymal maturation and also the inhibition of sperm-oolemmal adherence by pretreatment of the sperms with anti-HABP antibodies. We have further observed its in vivo phosphorylation in motile spermatozoa. All our data clearly indicate that sperm hyaluronan binding protein may have a specific role in sperm maturation, motility, and fertilization processes.
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PMID:Evidence for presence of hyaluronan binding protein on spermatozoa and its possible involvement in sperm function. 751 32

The effects of ingestion of sodium fluoride (NaF), 10 mg/kg body weight for 50 days, on the structure and metabolism of sperm of albino rats (Rattus norvegicus), were investigated. In different groups of rats, the reversible effects upon withdrawal of NaF treatment and by administering some therapeutic agents, viz., ascorbic acid and calcium alone and in combination with NaF (50 and 70 days), on sperm structure and metabolism were also studied. The results revealed that the sperm acrosomal hyaluronidase and acrosin were reduced after 50 days of NaF treatment. Sperm stained with acidic alcoholic silver nitrate revealed acrosomal damage and deflagellation, which might be causative factors for the reduced activity of the enzymes. These alterations also resulted in a decline in sperm motility. The cauda epididymal sperm count was decreased, perhaps because of spermatogenic arrest. Thus, the low sperm motility and count ultimately contributed toward reduction in fertility by NaF treatment. However, withdrawal of NaF treatment for 70 days produced incomplete recovery, while administration of ascorbic acid and calcium, individually and in combination, brought about significant recovery of fluoride-induced effects. Thus, the effects of fluoride on sperm structure and metabolism of rats are transient and reversible.
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PMID:Reversible effects of sodium fluoride ingestion on spermatozoa of the rat. 788 87

Enhancer caltrin permeabilizes the plasma membrane of bovine epididymal spermatozoa as indicated by the release of hyaluronidase from the acrosome and lactate dehydrogenase (LDH) from the sperm cytosol. A previously reported increased calcium uptake by the sperm in the presence of enhancer caltrin was apparently due, in part, to calcium entry into the mitochondria, which had become accessible to external calcium. At 37 microM (200 micrograms/ml), enhancer caltrin released about 30% of the total hyaluronidase in the acrosome and 50% of the cytosolic LDH from epididymal sperm (4 x 10(7)/ml). This event was prevented by phosphatidylserine (PS), presumably through caltrin-phospholipid complex formation, whereas phosphatidylcholine (PC) was ineffective. Cardiolipin induced the release of LDH and this too was prevented by enhancer caltrin. Lysophosphatidylserine (LPS), on the other hand, potentiated the lysogenic activity of enhancer caltrin, promoting the release of the full complement of hyaluronidase and LDH even at a molar ratio of only 1:1 with caltrin. The effect of mixtures of LPS and PS on the lysogenic property of enhancer caltrin was investigated, and it was found that PS suppressed the potentiating effect of LPS. Release of hyaluronidase and LDH took place only when the LPS/PS molar ratio was greater than 2. The implications of these findings for the role of caltrin in mammalian fertilization are discussed.
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PMID:Lysogenic activity of enhancer caltrin and the influence of phospholipids on its expression. 821 34

The rat sperm surface antigen, 2B1, that has been proposed to play a key role in sperm adhesion to the zona pellucida, has been cloned and its entire cDNA sequenced. Northern blot analysis indicates that 2B1 is encoded by a 2.2-kb RNA transcript that is abundantly expressed in the testis. The deduced protein sequence contains 512 amino-acid residues with a strong candidate signal sequence and C-terminal transmembrane domain. Data base searches reveal a high degree of sequence similarity to guinea pig, rabbit, monkey, and human PH20 sperm surface antigens, and a lower degree of similarity to honey bee and whiteface hornet venom hyaluronidases. Rat 2B1 antigen also possesses hyaluronidase activity, suggesting that it is a bifunctional protein with putative roles in the dispersion of cumulus oophorus cells as well as zona adhesion. However, while it would appear that 2B1 is the rat homologue of the guinea pig PH20 antigen, they differ in a number of important biochemical respects (including their mode of attachment to the sperm membrane and distribution between soluble and membrane-bound fractions), as well as in their localization on the sperm membrane. Expression of regions of the 2B1 protein in recombinant bacterial cells has allowed a preliminary mapping of the 2B1 epitope, and has provided more definitive information on the endoproteolytic processing of 2B1 during epididymal transit.
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PMID:Molecular cloning and characterization of rat sperm surface antigen 2B1, a glycoprotein implicated in sperm-zona binding. 891 77

Guanidinobenzoatase (GB), a serine proteinase with a molecular weight of 71,000, is found both free in the epididymal fluids of the mouse and bound to the sperm surface. Microgram quantities of the enzyme, purified from epididymal fluid, will completely disperse follicle cells from freshly ovulated oocytes after 15 min of incubation. Purified GB exhibits no hyaluronidase activity as determined by the acid albumin assay. The ability of GB to disperse follicle cells is blocked by a proteinase inhibitor endogenous to the male reproductive tract. The inhibitor has no effect on bovine testicular hyaluronidase. Although the function of GB has not been defined, the observations presented here indicate that it may play a role in cumulus matrix penetration during fertilization.
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PMID:Cumulus cell dispersal from murine oocytes by an epididymal guanidinobenzoatase. 929 43

Effects of a combination of medoxy-progesterone acetate (MPA) and dihydrotestosterone (DHT) at a dose of 10 mg + 2 mg/kg, injected, in weekly to rats of proven fertility were investigated with respect to their fertility, sperm and organ functions. This hormonal regimen had no effect in body and organ weights except in the testis. A depletion in sperm reserves in testis and epididymis was noted in addition to a loss of their motility in the later. Alterations in cauda epididymal sperm viability and morphology and reduced levels of superoxide dismutase indicated changes in their plasma membrane permeability. Sperm acrosomal enzymes such as acrosin and hyaluronidase were also affected leading to a loss of their function. Consequently the fertility potential of these rats also impaired after 60 days of hormonal regimen. Testicular biochemical machinery revealed its altered metabolism and regressed spermatogenic activity accounting for its loss of weight. Similarly epididymal physiology also exhibited changes leading to impaired sperm maturation. However, toxicity studies showed no significant variations in liver and blood biochemical profiles indicating non-toxic nature of this combination. All these effects seemed to be transient and reversible upon withdrawal of treatment for 60 and 90 days gradually. Thus, this combination with aromatizable androgen is useful for induction of functional sterility.
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PMID:Endocrine approach to male fertility control by steroid hormone combination in rat Rattus norvegicus L. 983 78

Indirect immunofluorescence of mouse caput and caudal sperm shows distinctly different distributions of Spaml protein, which is associated with structural and functional differences of the molecule. Spam1 is uniformly distributed over the surface of the head of caput sperm while in caudal sperm, light and confocal microscopy demonstrate that it is localized to the anterior and posterior regions. The hyaluronidase activity of Spaml in acrosome-intact caput sperm was significantly lower (4.3-fold; P < 0.0001) than that of caudal sperm. The increase in enzymatic activity in caudal sperm is accompanied by a reduction in the molecular weight (MW): in extracts from caput sperm there was a major band at approximately 74 kDa and a minor band at approximately 67 kDa; while for the cauda there was a major band at approximately 67 kDa and minor bands at approximately 70 and -56 kDa. Additionally, the bands from caput sperm were 4.9 to 7.7-fold less intense than those from caudal sperm. This decreased affinity for the polyclonal anti-Spaml suggests the presence of different surface characteristics of the molecule from the two epididymal regions. Computer analysis of the protein structure from Spam1 cDNA sequence reveals four putative N-linked glycosylation sites, and enzymatic deglycosylation suggests that all sites are functional. After endoglycosidase activity of extracts from caput and caudal sperm, both show a major band with a MW of approximately 56 kDa, the size of the membrane-anchored polypeptide backbone. Based on the difference in size and intensity of the Spaml bands and hyaluronidase activities from caput and caudal sperm, the data suggest that the activation of Spaml during epididymal maturation is regulated by deglycosylation.
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PMID:Biochemical maturation of Spam1 (PH-20) during epididymal transit of mouse sperm involves modifications of N-linked oligosaccharides. 989 Jul 51

The gene for the sperm adhesion molecule 1 (PH-20), SPAM1, has been known to be testis-specific and exclusively haploid expressed. We show that in mice, the 2 common isoforms of the protein (Spam1) observed in sperm are also present in the caput, corpus, and cauda epididymides. Both qualitative and quantitative variation of expression of the protein were observed in epididymis with the highest expression detected in the corpus. The endogenous production of enzymatically active (via hyaluronidase) Spam1 by epididymal cells is supported by the detection of steady-state Spam1 epididymal messenger RNA in both wild type and germ cell-deficient mice. In situ transcript hybridization shows the transcript to be localized to the principal cells of the epithelium. The protein was similarly immunolocalized to these cells, predominantly in vesicles near the apical region. The results suggest a mechanism for transportation of Spam1 from the epididymal epithelium to sperm during their transit and storage in the cauda. None of the current categories of spermatogenic-expressed genes shows the dual transcription pattern (haploid testicular/diploid epididymal) observed for Spam1. The work also confirms and extends the finding that Spam1 is expressed in the kidney.
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PMID:Mouse Spam1 (PH-20): evidence for its expression in the epididymis and for a new category of spermatogenic-expressed genes. 1110 8

To elucidate the mechanism of sterility induced by gossypol, we studied the relationship between the activities of acrosomal enzymes and their fertilizing capacity in the hamster. The results showed that the ability of spermatozoa to penetrate into bovine cervical mucus, hyperactivated motility (HAM) and fertility in vivo were significantly inhibited when spermatozoa were exposed to gossypol (2.5 microg - 60 microg/mL) for 15 min in vitro. Also, following administration of gossypol (12.5 mg/kg/day) for 6 weeks, sperm motility, HAM and rate of fertilization in vitro by the hamster cauda epididymal spermatozoa were significantly decreased and the extracts of testis delayed dispersion of the cumulus oophorus cells, suggesting that hyaluronidase and other acrosomal enzymes might be inhibited by gossypol. In addition, acrosin and arylsulfatase activities were also markedly inhibited. These data show that the inhibition of acrosin and arylsulfatase activities is the main cause of gossypol-induced infertility. The inhibition was dependent upon gossypol dose and the duration of administration. Thus, the assay of acrosin and arylsulfatase activities may provide a useful tool for monitoring sterility induced by gossypol.
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PMID:Inhibition of hamster sperm acrosomal enzyme by gossypol is closely associated with the decrease in fertilization capacity. 1113 75

It is generally accepted that spermatozoa become functionally mature during epididymal transit. The objective of this study was to determine whether the cellular location of equine PH-20 is modified during epididymal transit and, if so, the mechanism for such modification. Sperm were isolated from caput and cauda epididymal regions from stallions undergoing castration (n = 7) and used as whole sperm cell or subjected to nitrogen cavitation for isolation of plasma membrane proteins. Both caput and cauda sperm and sperm protein extracts were subjected to N-deglycosylation, O-deglycosylation, or trypsinization. The SDS-PAGE and Western blot analysis using a polyclonal anti-equine PH-20 IgG were performed in sperm extracts, and indirect immunofluorescence on whole sperm was also performed to determine the cellular distribution of plasma membrane PH-20 following similar treatments (deglycosylation or trypsinization). Hyaluronan substrate gel electrophoresis was performed to detect hyaluronidase activity in SDS-PAGE proteins. Western blots revealed significant differences in electrophoretic migration of PH-20 proteins from caput and cauda epididymal sperm. No effect was seen from deglycosylation treatments on the Western blot pattern; caput protein extracts exposed to trypsin showed the same band pattern as extracts from the cauda epididymis. N-deglycosylation resulted in the loss of hyaluronidase activity of sperm from both epididymal regions, whereas O-deglycosylation or trypsinization did not affect hyaluronidase activity. In caput epididymal sperm, the PH-20 protein is distributed over the entire sperm head; in cauda epididymal sperm, it is restricted to the postacrosomal region. No effect from deglycosylation on the cellular distribution of PH-20 was observed; however, treatment with trypsin changed the cellular distribution of PH-20 in caput sperm similar to that of the distribution of cauda sperm. These results suggest that PH-20 distribution during epididymal maturation is dependent on proteolytic trypsin-like mechanisms and, possibly, on complementary membrane-associated factors.
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PMID:Posttranslational processing of PH-20 during epididymal sperm maturation in the horse. 1167 46


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