Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P56851 (epididymal)
 11,273 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A major secretory protein of the human epididymis that is taken up by maturing spermatozoa is homologous to the leukocyte antigen CD52. The epididymis was shown to be the sole source of CD52 in seminal fluid, since CD52 could be detected in seminal plasma from sperm-containing ejaculates and not in ejaculates of vasectomized patients by Western blot analysis. The glycoprotein is not expressed in the testes. A fluorescence immunobinding assay was developed to quantify the amount of epididymal secretion of CD52 in the seminal plasma of various groups of fertile and infertile patients. Donor spermatozoa bearing CD52 were used as binding site tracers for free anti-CD52 antibody remaining after it had adsorbed CD52 from the seminal plasma to be assayed. The level of subsequent antibody binding to spermatozoa was measured by flow cytometry and the extent of binding inhibition was compared to a reference pool of seminal plasma to provide relative amounts of CD52 in test seminal plasma. There were no correlations between seminal plasma CD52 concentration and any semen parameter tested, including sperm concentration, percentage motility, normal sperm morphology or the concentration of seminal neutral alpha-glucosidase, fructose and zinc. There was a slight tendency towards an inverse relationship with the amount of CD52 on spermatozoa, but this was not significant. No differences were found among groups of patients classified by their semen parameters or fertility status. These findings indicate that the epididymal specific supply of CD52 is not a limiting factor for CD52 uptake onto spermatozoa.
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PMID:Epididymal secretion of CD52 as measured in human seminal plasma by a fluorescence immunoassay. 966 31

This article first examines the events occurring in male and female genital tracts, which prepare human sperm to encounter the egg. Central is a glycoprotein, gp20, homologous to the leukocyte antigen CD52. This protein is secreted in the epididymal cells, inserted in the sperm plasma membrane and exposed in the equatorial region of the head at the end of the capacitation process. The mechanisms and molecules of the first interaction event between gametes in the mollusk bivalve Unio elongatulus and the current state of our knowledge of the same interaction in other species is then considered. The egg of Unio is very peculiar because it is highly polarized. Similar to other well-known egg models, the ligand for recognition is located on the egg coat which is a sort of fibrous network made up of very few glycoproteins, while the receptor is on the sperm surface. The difference is that in this egg, the ligand molecules are not uniformly distributed but are restricted to an area of the egg coat at the vegetal pole, the crater area. The role of carbohydrates in ligand function and of a specific type of oligosaccharide chain in particular, is discussed in the wider context of glycans acting as recognition signals.
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PMID:Sperm-egg interaction at fertilization: glycans as recognition signals. 1106 24

Protein tyrosine phosphatases (PTPases) play an essential role in the regulation of steady-state phosphorylation of the insulin receptor and other proteins in the insulin signaling pathway. To determine the role of PTPases in adipose tissue in the development into an insulin-resistant state, we examined PTPase activities and protein levels of three major candidate PTPases in adipose tissues of 26-week-old male Otsuka Long-Evans Tokushima Fatty (OLETF) rats. Particulate PTPase activities in visceral and epididymal adipose tissues of OLETF rats were increased compared to those in Long-Evans Tokushima Otsuka (LETO) rats, non-insulin-resistant controls. Cytosolic PTPase activities in these tissues were conversely decreased in OLETF rats. In subcutaneous adipose tissues, those changes were not observed. Western blot analysis showed that the amounts of leukocyte antigen-related PTPase (LAR), PTPase 1B (PTP1B), and src homology 2-containing PTPase (SH-PTP2) were increased in particulate fractions of visceral and epididymal fat of OLETF rats. On the other hand, those in the cytosolic fractions were slightly decreased. Troglitazone was administered to OLETF rats to examine the effect of the drug on the changes in PTPase activity and distribution. Troglitazone treatment restored those alterations in PTPase activity in the particulate fraction and the amounts of LAR, PTP1B and SH-PTP2 in both fractions of visceral and epididymal adipose tissues of OLETF rats. Although it remains unknown whether such effects of troglitazone are mediated by peroxisome proliferator-activated receptor y, these data provide useful information for understanding the significance of PTPase in insulin-resistant rats and the molecular mechanism of troglitazone action.
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PMID:Troglitazone ameliorates abnormal activity of protein tyrosine phosphatase in adipose tissues of Otsuka Long-Evans Tokushima Fatty rats. 1236 58