Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.26.9 (ribonuclease)
 6,589 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The activity of 5'-nucleotidase (EC 1.3.5), cyclic nucleotide phosphodiesterase (EC 2.1.4.17), non-specific phosphodiesterase (EC 3.1.4.1) and ribonuclease (EC 1.7.7.16)has been investigated in the seminal plasma of whole semen and in the secretions of the seminal vesicle, prostate and epididymis of the bull, boar, ram, stallion, jackass, rabbit and man. Bull seminal plasma showed the highest activity for 5'-nucleotidase, cyclic nucleotide phosphodiesterase and ribonuclease; in contrast, stallion and jackass semen were very poor in these enzymes. Ram, rabbit and boar seminal plasma showed intermediate levels for all enzymes studied. In the bull and ram, nucleolytic enzymes were found to be secreted by the seminal vesicles but in the boar, rabbit and stallion they originate mostly from the epididymis. In human seminal plasma all of the enzymes studied exhibited activity but the levels were generally lower than those recorded for the other species.
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PMID:The activity of some nucleolytic enzymes in semen and in the secretion of the male reproductive tract. 19 15

The pattern of proteins in the soluble fraction of the cytoplasm of the rat epididymis was studied by acrylamide gel electrophoresis. The components of five distinct bands, labelled A, B, C, D and E, were found to be sensitive to changes in androgen in the blood. Castration for 14 days produced a sharp decrease in the colour intensity of bands B-E when stained with Amido black. After 21 days of castration, bands D and E were undetectable, bands B and C were severely diminished and band A was more intense. Seven days of replacement with testosterone (1 mg/day) induced a return towards a normal pattern. The degree of restoration was inversely proportional to the duration of castration. Quantitation by densitometry showed that the relative contributions of bands B-E to the region A-E were 61% in the control rat, only 27% after 21 days of castration and 35% when testosterone was given between days 14 and 21 of castration. The components of bands A-E are presumed to be proteins since the electrophoretic pattern was altered by digestion with pronase but not by ribonuclease, phospholipase C or neuraminidase. Epididymides from castrated and androgen-treated castrated rats were incubated with 14C- and 3H-labelled mixed amino acids respectively. After co-electrophoresis the ratio 3H: 14C rose from a baseline of 2-5 in band B, 32 in band C and 7 in bands D and E. Molecular weights were estimated as 27900 for B, 23100 for C and 34400 for D. Band A had the same electrophoretic mobility as serum albumin. Bands B and C were also present in testicular cytosol. Bands D and E were only found in the epididymis, localized mainly within the lumen of the tubules. Bands B-E increased with age during sexual maturation, bands D and E became detectable in the 20-day-old rats. Preliminary evidence indicates that the proteins in bands C, D and E can be removed from caput spermatozoa by washing.
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PMID:Androgen-controlled specific proteins in rat epididymis. 127 Sep 59

Spermatozoa from the cauda of the epididymis of the hamster and rat were incubated with [5-(3)H]uridine and glucose. By using a procedure avoiding bacterial and other cellular contamination, sonic extracts were prepared and digested with deoxyribonuclease and Pronase. Radioactive RNA of high molecular weight was isolated by two methods: (a) gel filtration on Sephadex G-75 columns and (b) polyacrylamide-gel electrophoresis in which it migrated in the region of 28S and 23S RNA markers. The macromolecules were alkali-labile and hydrolysed by ribonuclease. From (3)H radioactivity and E(260) of the isolated RNA the rate of incorporation of uridine into RNA of spermatozoa was calculated to be 0.1-0.5nmol/h per mg of RNA.
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PMID:Ribonucleic acid synthesis by spermatozoa from the rat and hamster. 474 26

A biochemical study was made on the effects of low doses of alpha-chlorohydrin on the protein and nucleic acid metabolism of the rat testis and epididymis. RNA and protein levels were decreased both in the testis and epididymis. The DNA content of the testis and epididymis did not change after exposure of the animals to the drug. The reduced concentrations of RNA and protein were closely paralleled by the increased activity of proteinase (protein hydrolyzing enzyme) and ribonuclease (RNA degrading enzyme) in the testis and epididymis. The gamma-glutamyl transpeptidase activity of both the testis and epididymis was also reduced indicating the slow transfer of amino acids across the cell membranes of testis and epididymis and thus low protein synthesis. The DNAase levels of rat testis and epididymis did not show any appreciable change in response to the alpha-chlorohydrin treatment. These studies indicate that although there may not be any histological damage in the tissue the metabolic pathways may become defective much earlier before any visible morphological change is discernible.
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PMID:Biochemical observations on the protein and nucleic acid metabolism of the rat testis and epididymis after treatment with low doses of alpha-chlorohydrin. 616 92

Wistar male rats received an intratesticular injection (at 114 and 265 days of age) of 3 mg of partially purified bull seminal ribonuclease (AS RNase) or saline. It was found that sexual behaviour (initiation of copulation as well as copulatory behavioural pattern) of experimental males was not changed, but the ability of these males to fertilize females was evidently suppressed. In addition to significantly lower weights of testes and epididymis, inhibition of seminiferous epithelium development (aspermatogenesis) associated with the absence of spermatozoa was determined in cauda epididymidis in experimental animals. However, Leydig cells remained without changes. Plasma testosterone levels of AS RNase treated males were not altered in comparison with the controls. Thus AS RNase specifically impaired spermatogenesis but did not influence androgen action and sexual behaviour.
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PMID:The effect of bull seminal ribonuclease on reproductive organs and sexual behaviour in male rats. 645 96

Multiple gamma-glutamyl transpeptidase (GGT) messenger RNAs (mRNAsII-IV) are expressed in a region-specific manner in the rat epididymis. In the present study, we examined the role(s) of plasma testosterone (T) and testicular factors in regulating the region-specific pattern and quantity of GGT mRNAs expressed along the epididymal duct. Northern blot and ribonuclease protection analyses showed that bilateral orchiectomy for 1, 5, and 15 days dramatically reduced the expression of GGT mRNAsII-IV in the initial segment. Expression of GGT mRNAII and mRNAIII was maintained in the initial segment of orchiectomized animals receiving T implants that maintain normal serum T concentrations, but GGT mRNAIV expression remained low relative to sham-operated control values. Unilateral efferent duct ligation decreased GGT mRNAIV expression only in the initial segment. Hence, expression of GGT mRNAIV in the initial segment was not maintained by circulating T and required a factor(s) of testicular origin. In caput epididymidis, expression of GGT mRNAII and mRNAIII declined after orchiectomy and was not completely restored to control values in orchiectomized animals by plasma T alone, but also required a testicular factor(s). In contrast to the initial segment, expression of GGT mRNAIV in the corpus and cauda epididymidis did not require T and/or a testicular factor(s), as expression of this transcript remained unchanged in these regions after 1, 5, and 15 days of orchiectomy, orchiectomy and T replacement, and after unilateral efferent duct ligation. In the cauda epididymidis, expression of GGT mRNAII required circulating androgens and was unaffected by unilateral efferent duct ligation, whereas GGT mRNAIII expression was repressed by T. These data demonstrate that circulating T and a factor(s) of testicular origin differentially regulate the expression of each GGT mRNA in a region-specific manner.
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PMID:Expression of multiple gamma-glutamyl transpeptidase messenger ribonucleic acid transcripts in the adult rat epididymis is differentially regulated by androgens and testicular factors in a region-specific manner. 791 28

Expression of the activated neu oncogene in transgenic mice has been associated with both the synchronous (single-step) and the stochastic (multistep) transformation of the mammary epithelium. To determine the basis for these conflicting observations, additional strains of transgenic mice carrying the activated neu oncogene under the transcriptional control of the mouse mammary tumor virus promoter/enhancer were produced. Activated neu transgene expression, as measured by in situ hybridization and ribonuclease protection assays, resulted in rapid conversion of the normal mammary epithelium to malignant phenotype in three independent strains of mice. Expression of the transgene in male mice led to epithelial hyperplasia of the epididymis and male infertility but not malignancy. These results indicate that tissue context is an important parameter in malignant progression and that expression of appropriate levels of activated neu is sufficient for rapid production of mammary tumors in transgenic mice.
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PMID:Activated neu induces rapid tumor progression. 863 5

In mammals, glutamine synthetase (GS) is expressed in a large number of organs, but the precise regulation of its expression is still obscure. Therefore a detailed analysis of the activity of the upstream regulatory element of the GS gene in the transcriptional regulation of its expression was carried out in transgenic mice carrying the chloramphenicol acetyltransferase (CAT) gene under the control of the upstream regulatory region of the GS gene. CAT and GS mRNA expression were compared in liver, epididymis, lung, adipocytes, testis, kidney, skeletal muscle and gastrointestinal tract, both quantitatively by ribonuclease-protection analysis and topographically by in situ hybridization. It was found that the upstream regulatory region is active with respect both to the level and to the topography of GS gene expression in liver, epididymis, gastrointestinal tract (stomach, small intestine and colon) and skeletal muscle. On the other hand, in the kidney, brain, adipocytes, spleen, lung and testis, GS gene expression is not or only partly regulated by the 5' enhancer. A second enhancer, identified within the first intron, may regulate GS expression in the latter organs. Furthermore, CAT expression in the brain did not co-localize with that of GS, showing that the 5' regulatory region of the GS gene does not direct its expression to the astrocytes.
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PMID:Role of the 5' enhancer of the glutamine synthetase gene in its organ-specific expression. 916 92

Glutamine synthetase (GS) converts ammonia and glutamate into glutamine. We assessed the activity of the 5' regulatory region of the GS gene in developing transgenic mice carrying the chloramphenicol acetyltransferase (CAT) gene under the control of 3150 bp of the upstream sequence of the rat GS gene to obtain insight into the spatiotemporal regulation of its pattern of expression. To determine the organ-specific activity of the 5' regulatory region CAT and GS mRNA expression were compared by ribonuclease-protection and semi-quantitative in situ hybridization analyses. Three patterns were observed: the 5' region is active and involved in the regulation of GS expression throughout development (pericentral hepatocytes, intestines and epididymis); the 5' region shows no activity at any of the ages investigated (periportal hepatocytes and white adipose tissue); and the activity of the 5' region becomes repressed during development (stomach, muscle, brown adipose tissue, kidney, lung and testis). In the second group, an additional element must be responsible for the activation of GS expression. The last group included organs in which the 5' regulatory region is active, but not in the cells that express GS. In these organs, the activity of the 5' regulatory region must be repressed by other regulatory regions of the GS gene that are missing from the transgenic construct. These findings indicate that in addition to the 5' regulatory region, at least two unidentified elements are involved in the spatiotemporal pattern of expression of GS.
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PMID:Organ-specific activity of the 5' regulatory region of the glutamine synthetase gene in developing mice. 934 14

The expression of the androgen receptor in the human epididymis was analysed by ribonuclease protection, in-situ hybridization and immunohistochemistry. Androgen receptor mRNA and protein could be detected throughout the entire organ, albeit in different quantities, in the caput, corpus and cauda regions, respectively. Also positive, though only weakly, was the ductus deferens, while the efferent ducts were devoid of specific signals. In-situ transcript hybridization and immunocytochemistry localized androgen receptor mRNA and protein primarily to the epithelium of the epididymal duct. In the ductal epithelial cells androgen receptor immunoreactivity showed a distinct nuclear distribution. While peritubular cells occasionally displayed weak signals, interstitial cells as well as blood vessels were consistently negative throughout the entire organ. The observed pattern of androgen receptor expression in the human epididymis supports the notion that the structure and function of the epididymis is differentially controlled by androgens in a region-specific manner, whereas it would not seem compatible with a direct role for androgens in the regulation of epididymal blood flow.
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PMID:Region-specific expression of the androgen receptor in the human epididymis. 943 17


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