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)

The gametes of an insectivore, the white-toothed shrew, Crocidura russula monacha, present certain idiosyncratic features not seen in most other eutherian mammals. The spermatozoa display an acrosome of giant proportions, and are produced in relatively small numbers. In trans-illuminated oviducts examined with DIC optics, spermatozoa were first sequestered in languid clutches within the isthmus in deep narrow crypts, with some eventually ingested by the crypt epithelium. Then, at ovulation (ca. 15 hr after hCG), many ascended to occupy "bubble-like" ciliated crypts distributed randomly within the ampulla, as active groups of acrosome-intact spermatozoa. However, eggs (3.95; range 2-6) were first retained for several hours and were fertilized in an upper crypt-free infundibulum before moving down to the ampulla. At fertilization, individual spermatozoa penetrate an unusually compact matrix-free cumulus oophorus which is stabilized by intercellular junctions, is insensitive to hyaluronidase, and persists for approximately 13 hr around fertilized and for approximately 24 hr around unfertilized eggs. In contrast to the free ampullary spermatozoa, active spermatozoa accumulating within the cumulus all had shed the acrosome, an observation consistent with evidence from other shrews suggesting that the cumulus may necessarily induce the acrosome reaction in this ancient line. Hypertrophy of the acrosome, isthmic sperm storage crypts, and stable cumulus oophorus that develops a peri-zona space, all may prove to be typically crocidurine characteristics of use where the classification of a shrew is in doubt.
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PMID:Novel sperm crypts and behavior of gametes in the fallopian tube of the white-toothed shrew, Crocidura russula monacha. 906

PH-20, a testis-specific protein first expressed in haploid germ cells, is present on the posterior head plasma membrane and inner acrosomal membrane of mature guinea pig sperm. PH-20 is bifunctional, having a hyaluronidase activity that allows sperm to penetrate the cumulus layer and a separate activity required for binding of acrosome-reacted sperm to the zona pellucida. The immunization of male guinea pigs with PH-20 reproducibly results in infertility with a duration of 6-12 mo or longer. In this study, we analyzed the immunopathology in the reproductive tract of PH-20-immunized males to probe the mechanism(s) responsible for the induced infertility and found two separate effects. Remarkably, in almost all infertile, PH-20-immunized males, the caudae epididymides were empty (contained no sperm) or contained only abnormal sperm. The complete loss of normal sperm in the epididymis apparently results in infertility. A second effect was the induction of experimental autoimmune orchitis (EAO), representing the first report of EAO induced by a purified testis/sperm molecule of known functions. PH-20-induced EAO differed from EAO induced by crude testis antigens in two respects: 1) an absence of epididymitis with abscess and granuloma and 2) the presence of antibody on germ cells within seminiferous tubules and inside the cauda epididymidis. The former suggests that crude testis antigens other than PH-20 are responsible for epididymitis, and the latter suggests a possible role of antibody in EAO pathogenesis and infertility induction. Return to fertility, after 6-12 mo, was accompanied by regression of EAO and reappearance of spermatozoa in the caudae epididymides.
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PMID:Mechanism of infertility in male guinea pigs immunized with sperm PH-20. 916 Jul 11

The gametes of the least shrew, Cryptotis parva, were studied in regard to their maturation and structure, and with particular emphasis on their behavior in the fallopian tube, from the time of ovulation until the appearance of two-cell embryos beginning some 9 h after ovulation. Cryptotis spermatozoa are organized according to the conventional eutherian mold, with the exception of a barbed perforatorium and an unusual plasma membrane density lent by a bristly coat where it overlies the acrosome rim. In the epididymis they undergo a maturation of the capacity for motility and an -S-S-related stabilization of the nucleus and tail organelles, with the cauda housing only approximately 4-5 million spermatozoa. Mating involves penile locking and also the deposition of a modest vaginal plug that covers the cervix. The short (4-5 mm) fallopian tube has three regions-a simple isthmus, a relatively narrow ampulla populated throughout by ciliated crypts, and a crypt-free terminal infundibulum-the fertilization site. Unlike the situation in most mammals, the tubal isthmus was devoid of spermatozoa in mated females before and after ovulation, which occurred approximately 13 h post-hCG and produced a mean of 5.7 ova. However, the ampulla then housed approximately 1500 active cells in groups within the ciliated crypts, sometimes together with leukocytes but with few spermatozoa above in the infundibulum. Within about 1 h after their ovulation from approximately 400-microm follicles, eggs were penetrated while in the infundibulum despite the nonexpanded hyaluronidase-resistant state of the cumulus oophorus. However, on moving down to the ampulla by 2-4 h after ovulation, the dense cumulus around fertilized eggs appeared to proliferate and began to disperse coincidentally with secretion of a hyaluronidase-sensitive matrix in which hundreds of motile spermatozoa often became enmeshed. This cumulus change also occurred around unfertilized eggs, though more slowly, but not around fertilized or unfertilized eggs cultured in vitro. Thus, cumulus matrix production appeared to be stimulated to an important degree by factors in the oviduct, not by preovulatory gonadotropins as in many mammals. Although cumulus-invested eggs were fertilized readily in vitro, cumulus-free eggs of the same age were never fertilized, and spermatozoa bound to the zona pellucida had intact acrosomes. This and related evidence from other shrews makes it seem likely that the soricid cumulus has an essential role in fertilization and may induce the acrosome reaction.
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PMID:Unusual ampullary sperm crypts, and behavior and role of the cumulus oophorus, in the oviduct of the least shrew, Cryptotis parva. 916 Jul 26

In the musk shrew, Suncus murinus, the behaviour of the cumulus-egg complex and its interaction with spermatozoa were unusual in several respects. The cumulus oophorus was ovulated about 15.5 h after mating or treatment with hCG as a hyaluronidase-insensitive matrix-free ball of cells which remained for relatively long periods of about 14 h around fertilized, and for about 24 h around unfertilized eggs. As a probable function of the small number of up to about 10 or 20 spermatozoa that generally reached the oviduct ampulla from isthmic crypts, there was often a delay of up to 10 h after ovulation before most eggs were penetrated. Soon after ovulation, however, the corona radiata retreated progressively from the zona pellucida, creating a closed perizonal space within the cumulus oophorus. Usually, most spermatozoa that did reach the ampulla were found within a cumulus and generally within that perizonal space. However, whereas the acrosome was intact among the few free ampullary spermatozoa, and in those adhering to the zona of cumulus-free eggs after delayed mating, all spermatozoa seen moving within the cumulus or adhering to the zona of unfertilized eggs had shed the giant acrosome. In accord with current observations in other shrews, the cumulus in Suncus may therefore function not only to sequester spermatozoa, but also as an essential mediator of fertilization-probably by inducing the acrosome reaction. In the absence of the acrosomal carapace that expresses the zona receptors in most mammals, fertilizing Suncus spermatozoa could use an unusual array of barbs on the exposed perforatorium to attach to the zona pellucida.
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PMID:The unusual state of the cumulus oophorus and of sperm behaviour within it, in the musk shrew, Suncus murinus. 922 66

Cysteamine (beta-mercaptoethylamine, or MEA) is a thiol-reducing agent and has anti-HIV activity. Because of these properties, cysteamine was evaluated as a vaginal contraceptive and tested for its effects on sperm function and on other sexually transmitted microbes. Cysteamine was contraceptive in the rabbit. Conception was inhibited completely when sperm were pretreated with 500 microg/ml cysteamine and was inhibited by more than 60% when 7.5 mg cysteamine was applied vaginally as a suspension in 50% K-Y Jelly. Cysteamine had multiple effects on spermatozoa. Both acrosin (EC 3.4.21.10) and hyaluronidase (EC 3.2.1.35) were reversibly inhibited by cysteamine. Calculated IC50 values were 370 microg/ml and 150 microg/ml for acrosin and hyaluronidase, respectively. Cysteamine behaved as a poor spermicide when activity was measured by the 30-second Sander-Cramer test. However, sperm motility was inhibited completely when cysteamine was preincubated for 10 minutes prior to motility evaluation, at concentrations as low as 50 microg/ml. The calcium ionophore A23187-induced human acrosome reaction was inhibited by cysteamine (IC50 = 0.5 microg/ml). Neither herpes simplex virus nor Neisseria gonorrhoeae was affected by cysteamine at concentrations as high as 500 microg/ml and 100 microg/ml, respectively. Cysteamine appears to have no effect on normal vaginal flora (i.e., lactobacillus). These results, together with published data, strongly support the further development of cysteamine as a topical contraceptive anti-HIV agent.
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PMID:Characterization of cysteamine as a potential contraceptive anti-HIV agent. 953 90

Ejaculated spermatozoa from infertile men presenting to our laboratory for semen analysis were processed with a new molecular method which reveals simultaneously, in the same sperm cell, the status of the acrosome, by testing the hyaluronidase content, the texture of the nucleus, by checking the DNA strands breaks, and the structure of the axoneme, revealing the tubulin content. The presence of hyaluronidase and tubulin is essential for the sperm function, and the analysis of the DNA status reveals the eventual apoptotic process. Using this method in normal spermatozoa, the staining of the acrosomal hyaluronidase reveals, by yellow-green fluorescence, the shape of the acrosomal complex and its texture. At the same time, in the same sperm cell, the staining of the axonemal tubulin demonstrates, by a red labeling, the presence of the protein and therefore the consistence of the axonemal structure. Simultaneously, at the head level, the absence of red labeling from nuclear DNA indicates that the apoptotic process is not present. This protocol allows quantification of the frequency of the presence of normal or abnormal spermatozoa, by an easy scoring and calculation of the apoptotic sperm or of the sperm with generic defects at acrosomal or flagellar level. The percentage of normal spermatozoa evaluated by the triple staining method has been compared with the results of the PAP staining and of the ultrastructural analysis, statistically elaborated. Triple staining results more severe than the PAP method, but TEM analysis is the finest technique to detect sperm abnormality because it considers the entire panel of sperm defects.
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PMID:A quick molecular method for the simultaneous detection in spermatozoa of nuclear, acrosomal and axonemal structure by fluorescent microscopy. 1068 96

Since moles are closely related to shrews, the gametes and reproductive tracts of the star-nose mole (Condylura cristata) and the eastern mole (Scalopus aquaticus) were examined to gain further insight into unusual reproductive traits of the Soricidae. Moles display many of these soricid traits, but with some important differences. The cumulus oophorus of Scalopus, ovulated about 16 h after hCG injection, was largely dispersed by hyaluronidase and, though quite dense, was nevertheless more similar to that of higher mammals than to the compact 'ball of the soricid cumulus. Within the female tract in these moles, approximately 85% of the length of the oviduct comprises a narrow ampulla with numerous differentiated crypts that, in shrews, house spermatozoa. However, in contrast to shrews, moles produce considerably larger numbers of spermatozoa, which challenges the proposal that, in shrews, oviductal sperm crypts specifically permit lower sperm production by the males. In the sperm head of these two moles, the acrosome displays the long rostrum that is typical of other Insectivora, and the perforatorium has the barbs by which soricid spermatozoa probably bind to the zona pellucida. Perhaps allied to this, immunoblots indicated that the immunoreactive acrosomal matrix of Scalopus spermatozoa is simpler than the polypeptide complex of the bovine and hamster acrosomal matrix.
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PMID:Reproductive features of the eastern mole (Scalopus aquaticus) and star-nose mole (Condylura cristata). 1069 Feb 3

We have previously reported the occurrence and partial characterisation of an alpha-D-mannosidase activity on plasma membranes of rat, mouse, hamster and human spermatozoa. A soluble isoform of the rat sperm surface mannosidase was purified and polyclonal antibody raised. Since several reports have suggested that mannosyl residues on the rat, mouse and human zona pellucida may be involved in sperm-zona binding, studies were undertaken to examine the receptor-like role of mannose-binding molecules on rat spermatozoa. Sprague-Dawley rats (25-30-days old) were superovulated and eggs collected from the oviduct were treated with 0.3% hyaluronidase to remove the cumulus cells. Spermatozoa, collected from the cauda epididymis were capacitated for 5 h at 37 degrees C in 5% CO2 in air. The sperm-zona binding assay was performed in the presence of increasing concentrations of several sugars as well as preimmune and immune (anti-mannosidase or anti-mannose binding protein) IgG. Data from these studies show that: (1) significantly fewer sperm bound per egg in the presence of competitive inhibitors of mannosidase; (2) among the sugars examined, D-mannose was the most potent inhibitor causing 70% reduction in the number of sperm bound per egg; (3) anti-mannosidase or anti-mannose binding protein (but not preimmune) IgG showed a dose-dependent reduction in the number of sperm bound per egg; (4) anti-mannosidase IgG (but not anti-mannose binding protein IgG) showed a dose-dependent inhibition of sperm surface mannosidase activity; (5) the competitive inhibitors of mannosidase or the immune IgG had no effect on sperm motility or the sperm acrosome reaction. These result suggest that mannose-binding molecule(s) such as alpha-D-mannosidase or mannose-binding protein on the spermatozoa may recognise mannosyl residues on zona pellucida, and play a receptor-like role in sperm-egg interaction in the rat.
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PMID:Mannose-binding molecules of rat spermatozoa and sperm-egg interaction. 1071 52

Rat sperm 2B1 antigen (the orthologue of guinea pig sperm PH20) is a plasma membrane-bound glycoprotein that is endoproteolytically cleaved during passage through the epididymis and subsequently migrates from the tail to the acrosomal domain during capacitation. Unlike guinea pig PH20, however, sperm surface 2B1 is insensitive to phosphatidylinositol phospholipase C, nor is it known how endoproteolytic cleavage affects its hyaluronidase activity. In this investigation we have expressed 2B1 cDNA in Chinese hamster ovary cells; we have shown that it contains an internal sequence motif for attachment of a glycosyl phosphatidylinositol (GPI) anchor and that cleavage from a single- into a two-chain molecule causes a significant shift in the optimum pH for hyaluronidase activity. Functionally, these results suggest that 1) 2B1 glycoprotein on rat spermatozoa is attached to the plasma membrane via a GPI anchor and that this is an important factor in its ability to migrate from the tail to the acrosomal domain during capacitation; and 2) endoproteolytic cleavage of 2B1 serves to optimize its hyaluronidase activity immediately before fertilization, thereby facilitating penetration of spermatozoa through the cumulus oophorus.
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PMID:Rat sperm 2B1 glycoprotein (PH20) contains a C-terminal sequence motif for attachment of a glycosyl phosphatidylinositol anchor. Effects of endoproteolytic cleavage on hyaluronidase activity. 1081 70

To obtain further perspective on reproduction and particularly gamete function among so-called primitive mammals presently grouped in the Order Insectivora, we have examined the African hedgehog, Atelerix albiventris, in light of unusual features reported in shrews and moles. Atelerix proves to share many but not all of the characteristics seen in these other insectivores. The penis of Atelerix has a 'snail-like' form, but lacks the surface spines common in insectivores and a number of other mammals. Hedgehog spermatozoa display an eccentric insertion of the tail on the sperm head, and they manifest the barbs on the perforatorium that, in shrews, probably effect the initial binding of the sperm head to the zona pellucida. As a possible correlate, the structural matrix of the hedgehog acrosome comprises only two main components, as judged by immunoblotting, rather than the complex of peptides seen in the matrix of some higher mammals. The Fallopian tube of Atelerix is relatively simple; it displays only minor differences in width and in the arborized epithelium between the isthmus and ampulla, and shows no evidence of the unusual sperm crypts that characterize the isthmus or ampulla, depending on the species, in shrews and moles. In common with other insectivores, Atelerix appears to be an induced ovulator, as judged by the ovulation of some 6-8 eggs by about 23 h after injection of hCG. The dense cumulus oophorus appeared to have little matrix, in keeping with the modest dimensions of the tubal ampulla and, while it was not quite as discrete as that of soricids, it did show the same insensitivity to 0.5% (w/v) ovine or bovine hyaluronidase.
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PMID:Reproductive characteristics of the african pygmy hedgehog, atelerix albiventris. 1100 56


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