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)

In the dasyurid marsupial, Sminthopsis crassicaudata, the mature spermatozoon has an inner homogeneous (C1) and a peripheral indented (C2) region. Using DNase-gold conjugates, and biotinylated genomic DNA probes, DNA was found to occur in both C1 and C2 regions. The morphogenesis of the spermatozoon nucleus was investigated using ultrastructural and cytochemical studies. Spermiogenesis was divided into 15 steps. By step 10, condensation of the C1 region was complete, and at the caudal extremity of the spermatid nucleus, the nuclear envelope enclosed an electron-lucent space. This space and the surrounding nuclear envelope became very enlarged at step 11. At this stage, a plate of approximately 70 nm in thickness was present along the caudal segment of the C1 region; this "nuclear mantle" did not bind DNase-gold conjugates but stained for lysine-rich proteins using alcoholic phosphotungstic acid. Chromatin condensation resumed at step 12 with the appearance of spherical chromatin structures peripheral to the C1 chromatin. These structures then partially coalesced and the indentations of the C2 region were observed. The expanded nuclear envelope at the caudal extremity persisted in caput epididymal spermatozoa. Spherical inclusions within it did not bind to DNase-gold conjugates but stained for lysine-rich proteins. As the sperm traveled down the epididymis, these inclusions amassed near the nuclear pores and were then removed from the nucleus. In addition, the nuclear mantle was found to have disappeared by the time the spermatozoa reached the corpus epididymidis.
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PMID:Ultrastructure of nuclear condensation and localization of DNA and proteins in spermatozoa of a dasyurid marsupial, Sminthopsis crassicaudata. 882 20

A protein designated as BE-20 was purified from cauda epididymal fluid of the rabbit by preparative polyacrylamide gel electrophoresis and HPLC on a mono Q HR5/5 anion exchange column. The purified protein migrated with an estimated Mt of 20,000 when analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The amino acid sequence of the N-terminus of the BE-20 protein was determined. The initial eight amino acid residues were His-Gly-Ala-Asp-Lys-Pro-Gly-Val. The corresponding 23 mer oligonucleotide (5'-CATGGCGCTGACAAGCCTGGGGT-3') was synthesized and used as sense primer with rabbit epididymal mRNA as template in the RT-PCR system. The purified BE-20 cDNA consisted of 499 bp with an open reading frame of 285 bp encoding a deduced polypeptide composed of 95 amino acids. The BE-20 cDNA had 78.5% identity in 479 bp overlap with human epididymis-specific HE4 cDNA. The amino acid sequences of the initial 30 amino acid residues of the N-terminus of the purified protein and the deduced polypeptides were as follows: N-His-Gly-Ala-Asp-Lys-Pro-Gly-Val-Cys-Pro-Gln-Leu-Ser-Ala-Asp-Leu-Asn-Cy s- Thr-Gln-Asp-Cys-Arg-Ala-Asp-Gln-Asp-Cys-Ala-Glu. The deduced polypeptide contained 16 cysteine residues and had partial sequence homology with proteins belonging to the four-disulfide core family of extracellular proteinase inhibitors. The BE-20 protein may play a role in sperm maturation and/or capacitation.
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PMID:Identification of a rabbit epididymal protein gene. 888 63

cAMP is important for the initiation of mammalian sperm motility. Previously we established that a type II cAMP-dependent protein kinase is tightly associated with the fibrous sheath of rat sperm. This unique cytoskeletal structure surrounds the 9+2 axonemal network in the principal piece of the flagellum. Association of the kinase to the fibrous sheath is mediated via its regulatory subunit, RII. An RII-binding overlay procedure was used to document that RII could specifically associate with fibrous sheath polypeptides of 120 and 80 kDa. In this study, we report the cloning of a rat testis-specific, developmentally regulated, RII-binding protein (TAKAP-80). A 1.2-kb cDNA clone, isolated by screening a rat testis expression library with 32P-labeled RII, hybridized to a 1.8-kb mRNA transcript present exclusively in testis. This transcript appeared at detectable levels at 30 days after birth. Over the next 10 days the mRNA levels increased greatly. This time interval corresponds to the initiation of spermiogenesis. The complete nucleotide sequence of TAKAP-80 cDNA was obtained by polymerase chain reaction and contained a continuous open reading frame of 502 amino acids. The deduced amino acid sequence showed a clear demarcation of charged and hydrophobic amino acid residues. Amino acids 1-147 of the protein contained 45% charged residues, with lysine and arginine predominating. Similarly, amino acids 268-502 also contained a high percentage of charged amino acids (35%). In contrast, amino acids 148-267 were mostly hydrophobic and contained clusters of a repeating PXXP motif where X was predominantly valine and alanine or sometimes proline. The 1.2-kb cDNA clone was inserted into the pRSET vector and expressed as a His6 tag fusion protein in Escherichia coli. The recombinant protein was soluble and bound RIIalpha, RIIbeta and type IIalpha holoenzyme by the RII-binding overlay procedure. Deletion analysis revealed that the high-affinity interaction site for RII was contained within amino acids 258-378 of TAKAP-80. Antibodies prepared against the fusion protein recognized an 80-kDa protein present in the urea-insoluble particulate fraction of rat testis and in purified fibrous sheath preparations isolated from rat epididymal sperm. Levels of the 80-kDa immunoreactive protein were significantly higher in mature (60 days old) compared with immature (30 days old) rat testis, correlating with the mRNA levels.
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PMID:Cloning and characterization of a testis-specific, developmentally regulated A-kinase-anchoring protein (TAKAP-80) present on the fibrous sheath of rat sperm. 920 34

Using mechanical and chemical dissection methods, fibrous sheath was isolated both from normal ejaculated human spermatozoa and from rabbit cauda epididymal spermatozoa. The same techniques did not produce a pure preparation of fibrous sheath from ejaculated rabbit spermatozoa, suggesting that further cross-linking and stabilization of sperm structures occurs in response to components of the seminal plasma. The isolation procedures were monitored by phase contrast microscopy and the purity of the fibrous sheath was verified by electron microscopy. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of isolated human fibrous sheath revealed at least 14 protein bands of which the most intensely stained were of molecular weight 84, 72, 66.2, 57, 32 and 28.5 kDa. The rabbit fibrous sheath revealed at least 10 protein bands, of which the most intensely stained were 35.2, 32.7 and 28.5 kDa. The amino acid composition of the purified fibrous sheath from human and rabbit spermatozoa was similar, being high in aspartic acid and/or asparagine and glutamic acid and/or glutamine, serine, alanine, leucine, lysine and glycine, but low in histidine, tyrosine and isoleucine. This composition is similar to that reported for the rat and suggests that mammalian sperm tail fibrous sheaths are composed of similar types of proteins, although there are apparent differences in protein components between species.
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PMID:Isolation and characterization of human and rabbit sperm tail fibrous sheath. 923 58

To identify a novel candidate(s) for acrosomal proteins that act on the sperm/egg interaction, a DNA fragment was PCR-amplified from a cDNA library of acrosin-deficient mouse testis and then used as a probe to screen a mouse testis cDNA library. Complementary DNA clones encoding each of two similar but different serine proteases, TESP1 and TESP2, have been identified. The nucleotide sequences of these clones indicate that mouse TESP1 and TESP2 are initially synthesized as preproproteins of 367 and 366 amino acids, respectively. Comparison of the two TESP sequences with those of typical serine proteases suggests that each TESP zymogen is probably converted into a two-chain mature enzyme consisting of light and heavy chains covalently linked by a single pre-existing disulfide bond. The conversion may be accomplished by another protease(s) with a trypsin-like cleavage specificity, since it is unlikely that the mature TESP1 and TESP2 are capable of splitting the Lys-Ile bond between the light and heavy chains. Northern blot analysis of total cellular RNA demonstrates that the TESP1 and TESP2 genes are expressed only in the testis, and the transcripts are abundantly present in the haploid round spermatids. Moreover, immunocytochemical analysis of mouse cauda epididymal sperm using affinity-purified antibodies reveals that these two TESPs are both localized in the sperm acrosome and are released during the acrosome reaction induced by calcium ionophore A23187. These findings provide additional clues for elucidating the mechanisms involved in the sperm/egg interactions, including penetration of the zona pellucida by sperm.
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PMID:Two novel testicular serine proteases, TESP1 and TESP2, are present in the mouse sperm acrosome. 958 71

Recent studies reported from our laboratory have established that the sustained delivery of danazol in combination with androgens resulted in the remarkable reduction of epididymal mass. In addition, previous studies have recommended that ultrastructural of epididymal tubules have to be elucidated. The specific objective of this investigation was to evaluate the cytological characteristics of epididymal tissues exposed to sustained delivery of dihydrotestosterone (DHT), dehydroepiandrsterone (DHEA) and a combination of Estrogen (E), DHEA plus DHT by means of tricalcium phosphate lysine (TCPL) delivery system. Adult male rats (BW 300-350 gm) were randomly divided into four equal groups: Group I animals were implanted i.p. with TCPL loaded with DHEA (100 mg). Animals in group II were implanted with TCPL capsules loaded with DHEA (100 mg) + DHT (500 mg). Group III animals were implanted with TCPL capsules loaded with E (200 mg) + DHEA (100 mg) + DHT (500 mg). Group IV animals served as the intact unimplanted controls. Surgical aseptic techniques were performed according to standard laboratory procedures. The animals were maintained at the University of Mississippi Medical Center Animal Facilities following the rules and regulations established by NIH on the Care and Use of Laboratory animals. At the end of 6 weeks post implantation, all animals were sacrificed and the epididymal tissues were collected, weighed, and embedded for histopathological evaluations. Statistical analysis was conducted by using standard computer programs (STATVIEW, ANOVA at 95% CI). The data obtained in this investigation demonstrated the following: (1) remarkable reduction in sperm counts and motility obtained from epididymal tubules in all experimental (hormonally treated) groups, (2) the lumen of the epididymal tubules were devoid of sperm in animals treated with DHT in comparison to the control, (3) a decrease in the diameter of tubules with occasional hypertrophic epithelium in all experimental animals, (4) disorganization of nuclear material was observed in animals treated with DHEA and DHEA + E + DHT in comparison to the control group. The overall observation of this study suggests that sustained delivery of DHEA, DHEA + DHT, and DHEA + DHT + E can be used to regulate the structural and functional architecture of the site of extramaturation of spermatozoa.
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PMID:TCPL delivery system: the role of DHT, DHEA, and E on the epididymal tubules of adult male rats. 960 9

The present study explores the mechanism underlying the action of L-arginine on the metabolic activity of spermatozoa. Goat epididymal spermatozoa were incubated with different concentrations of L-arginine to determine its effect on the utilization of glucose, fructose, and pyruvate. NMR techniques have been applied to elucidate the effect of L-arginine, L-lysine, and L-ornithine on the glycolysis of epididymal goat spermatozoa. Whereas 31P NMR has been used to estimate the change of pH in the presence of different concentrations of L-arginine, 13C NMR has been used to estimate the substrate consumption and lactate production. At optimal concentration of L-arginine, the forward metabolic rates have been found to increase by two to three times over control experiments. Arginine is not consumed in these reactions, but acts as an activator. Longitudinal relaxation time (T1) measurements indicate that the guanidino group of L-arginine plays an active role in binding to cells. The amino acid L-lysine is less effective, and L-ornithine is ineffective.
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PMID:Arginine activates glycolysis of goat epididymal spermatozoa: an NMR study. 972 54

Factors controlling the appearance in the epididymis of basal cells and their expression of macrophage antigens were examined by ligating the efferent ducts to prevent the entry of spermatozoa in adult and juvenile mice. Fixation and antigen retrieval techniques were developed to preserve tissue morphology and expression of two macrophage antigens in paraffin-embedded epididymal tissue. A combination of periodate-lysine-phosphate fixation, low-temperature embedding and enzyme predigestion of sections permitted immunohistochemical detection of the mature macrophage antigen Mac-1, whereas the panmacrophage marker F4/80 required fixation in neutral-buffered formalin. Epididymal basal cells were immunostained for F4/80 and quantified with avidin-biotin-peroxidase. In the adult mouse, the total number of basal cells per millimeter length of tubule cross section perimeter and the percentage expressing the F4/80-antigen were significantly higher in the initial segment and caput region than in all other epididymal regions. In the initial segment, immunostained basal cells surrounded the tubule in a network, and some extended towards the lumen. Ligation of the efferent ducts to prevent inflow of testicular secretions significantly reduced the number of basal cells per cross section in the initial segment of the adult and juvenile; the percentage of basal cells expressing macrophage antigens in the initial segment and the caput epididymidis was also reduced. Since basal cells still appeared in the ligated postpubertal epididymis, it is concluded that testicular exocrine secretions entering the epididymal lumen around puberty are not the major influence on basal cell appearance in the murine epididymis, but they may modulate their expression of macrophage antigens.
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PMID:Regional variation in macrophage antigen expression by murine epididymal basal cells and their regulation by testicular factors. 1059 13

Alpha1-microglobulin (alpha1m) is an electrophoretically heterogeneous plasma protein. It belongs to the lipocalin superfamily, a group of proteins with a three-dimensional (3D) structure that forms an internal hydrophobic ligand-binding pocket. Alpha1m carries a covalently linked unidentified chromophore that gives the protein a characteristic brown color and extremely heterogeneous optical properties. Twenty-one different colored tryptic peptides corresponding to residues 88-94, 118-121, and 122-134 of human alpha1m were purified. In these peptides, the side chains of Lys92, Lys118, and Lys130 carried size heterogeneous, covalently attached, unidentified chromophores with molecular masses between 122 and 282 atomic mass units (amu). In addition, a previously unknown uncolored lipophilic 282 amu compound was found strongly, but noncovalently associated with the colored peptides. Uncolored tryptic peptides containing the same Lys residues were also purified. These peptides did not carry any additional mass (i.e., chromophore) suggesting that only a fraction of the Lys92, Lys118, and Lys130 are modified. The results can explain the size, charge, and optical heterogeneity of alpha1m. A 3D model of alpha1m, based on the structure of rat epididymal retinoic acid-binding protein (ERABP), suggests that Lys92, Lys118, and Lys130 are semiburied near the entrance of the lipocalin pocket. This was supported by the fluorescence spectra of alpha1m under native and denatured conditions, which indicated that the chromophores are buried, or semiburied, in the interior of the protein. In human plasma, approximately 50% of alpha1m is complex bound to IgA. Only the free alpha1m carried colored groups, whereas alpha1m linked to IgA was uncolored.
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PMID:Alpha1-microglobulin chromophores are located to three lysine residues semiburied in the lipocalin pocket and associated with a novel lipophilic compound. 1063 76

Microencapsulation of islets of Langerhans within semipermeable membranes has been proposed to prevent their immune destruction after transplantation. However, the successful application of this method is impaired by a pericapsular reaction, which eventually induces graft failure. Our goal is to study the role of cytokines in the pathogenesis of this reaction, using the model of alginate-poly-L-lysine microcapsule implantation into Wistar rat epididymal fat pads (EFP). The specific objective of this study was to determine the time course of transforming growth factor (TGF)-beta(1) mRNA expression by semi-quantitative reverse transcriptase-polymerase chain reaction. Microcapsules induced an increase of TGF-beta(1) mRNA expression that reached a maximum 14 days after implantation. Seven, 14, 30, and 60 days after microcapsule implantation, the expression of TGF-beta(1) mRNA was significantly higher in pericapsular infiltrate cells than in nonimplanted EFP cells (p<0.05, p<0.0001, p<0.005, and p<0.01, respectively). Injection of physiological saline induced a small and gradual augmentation of TGF-beta(1) mRNA expression with a maximum 30 days after injection (p<0.01 vs. nonimplanted EFP cells). These results demonstrated that microcapsule implantation, in comparison with saline injection, induce an early, extended, and amplified TGF-beta(1) mRNA expression. This suggests that TGF-beta(1) plays a role in the pathogenesis of the pericapsular host reaction.
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PMID:Time course of transforming growth factor-beta(1) (TGF-beta(1)) mRNA expression in the host reaction to alginate-poly-L-lysine microcapsules following implantations into rat epididymal fat pads. 1090 70


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