Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.27.1 (RNase)
 16,360 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Five ribonuclease activities, separable by polyacrylamide gel electrophoresis, have been detected in erythroid bone marrow cells from anaemic rabbits. Their intracellular distribution has been investigated and compared with that of the ribonucleases in reticulocytes. Both the acid and alkaline ribonuclease activities of reticulocytes are much lower (30--50 fold) than those of bone marrow erythroid cells. The most marked decrease in enzyme activity occurs in the fractions containing ribosomes and mitochondria plus lysosomes. In these subcellular organelles there was also a qualitative change in the ribonuclease electrophoretic pattern, whereas the cytosol enzymes of marrow erythroid cells and reticulocytes remained largely unchanged. Several ribonucleases released from reticulocyte membranes with urea were similar to those present in the lysosomal plus mitochondrial fraction, as shown by detection of enzyme activity after polyacrylamide gel electrophoresis. The decline in ribonuclease activity was found to begin in the orthochromatic cells, which have a highly condensed nucleus and are no longer active in DNA and RNA synthesis, and to coincide with a decrease in acid phosphatase activity and loss of lysosomes.
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PMID:Intracellular distribution of ribonuclease activity during erythroid cell development. 1 51

The differentiation of rat liver lysosomal acid phosphatase, acid ATPase, acid phosphodiesterase, acid ribonuclease, and acid deoxyribonuclease was studied by isoelectric focusing. To prevent autolytic digestion, inhibitors of cathepsins and neuraminidase were used. The proportion of acidic forms of acid phosphatase, acid ATPase and acid phosphodiesterase was increased by the use of extraction medium containing 0.05% Triton X-100. To investigate the identity of acid ATPase and acid phosphodiesterase, the relative activities among the multiple forms of these enzymes, the acid phosphodiesterase/acid ATPase ratio at each activity peak, and the degree of enzyme inhibition by p-chloromercuriphenyl sulfonic acid were estimated. The results suggest that acid ATPase is not identical with acid phosphodiesterase. With extraction medium free of Triton X-100, acid ribonuclease appeared in two forms. However, in addition to these forms, a new form of this enzyme with a more acidic pI (4.22) emerged when extraction medium containing 0.05% Triton X-100 was used. The major peak of acid deoxyribonuclease with pI=8.40-9.39 was obtained regardless of the extracting method.
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PMID:An isoelectric focusing study of acid phosphohydrolases in rat liver lysosomes. 2 87

In an effort to develop a sensitive and specific method for detecting human prostatic cancer at early stages, we have studied the isoenzyme patterns of acid phosphatase in patients' sera as well as in benign hypertrophic and cancerous prostatic tissues using isoelectric focusing techniques. At least eight acid phosphatase isoenzymes at pI 4.1-5.5 could be observed. The sera with highly elevated acid phosphatase activity generally contained more isoenzymes with pI values of 4.5-5.0. The purified acid phosphatase isolated from benign hypertrophic and malignant prostatic tissues showed no qualitative difference in isoenzyme patterns although quantitative variations were observed. Malignant tissue contained more isoenzymes with pI values of 4.5-4.8. Patients' sera were found to contain isoenzymes of prostate origin. We have also investigated serum ribonuclease (RNase) activity in patients with prostatic cancer. The serum RNase activity of patients was significantly elevated. No significant correlation was observed between serum acid phosphatase and RNase activity. In some instances, where acid phosphatase activity was in the normal range, RNase activity was elevated. These data suggest that simultaneous measurements of RNase and acid phosphatase activities may be of value in the diagnosis of prostatic cancer. The purified RNase has been isolated from human prostatic tissue and its immunologic properties are being studied.
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PMID:Enzyme markers in human prostatic carcinoma. 6 22

The activity and sedimentation of acid phosphatase (APase), acid deoxyribonuclease (DNase), and acid ribonuclease (RNase) were investigated throughout growth and encystment in Acanthamoeba castellanii. The activities/mg protein of all 3 hydrolases are high in young cultures and decrease to constant levels in postlog cells. The RNase activity/ameba decreases 50% during growth, whereas the activity/cell of both APase and DNase remains constant. The percent sedimentation at 20,000 g of all 3 enzymes gradually increases from about 40% in midlog to a plateau of 80% in postlog cells. During encystment, the sedimentation behavior of RNase differs from that of APase and DNase. Encystment is characterized by a differential decrease in the activity/cell of the 3 hydrolases, with RNase decreasing most rapidly and APase least rapidly. APase is unique in that a transient increase of its specific activity is noted during encystment, even though its activity/cell is decreasing.
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PMID:Acid hydrolase activity during growth and encystment in Acanthamoeba castellanii. 18 46

The activity of certain enzymes of energy metabolism (cytochrome c oxidase, citrate synthase, malate dehydrogenase, and lactate dehydrogenase) and of lysosomes (beta-glucuronidase, beta-N-acetylglucosamindase, arylsuphatase, ribonuclease, deoxyribonuclease, acid phosphatase, and cathepsin D) was assayed from m. rectus femoris of mice trained 5 days per week, 1 hr per day for 4 weeks according to 4 different programmes: I. running speed 20 m/min, horizontal track, II. 25 m/min, horizontal track, III. 20 m/min 8 degrees uphill inclination, and IV. 25 m/min 8 degrees uphill inclination. Oxidative capacity increased and anaerobic capacity decreased without distinction between the different traning programmes. Of acid hydrolases assayed the activities of beta-glucuronidase and cathepsin D were increased independently of training intensity. Simultaneous histochemical observations on beta-glucuronidase and arylsulphatase activities in the contralateral m. rectus femoris showed more intense staining in red as compared to white muscle fibres. It is suggested that training affected the red fibres and that the applied level of loading was probably too low to cause major involvement of white fibres.
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PMID:Oxidative and lysosomal capacity in skeletal muscle of mice after endurance training of different intensities. 21 99

A comparison of results obtained from studies of the intracellular fractions of the tissues of liver, brain and heart of "young" (1-2 months), "old" (24-27 months) and "senile" (34-37 months) rats showed that the ratios of three enzymes, acid phosphatase, beta-N-acetylglucosaminidase and acid RNase of the liver and heart were very similar and their activities decreased with age. On the other hand, the protein content is the supernatant of the liver, and acid DNase activities in the supernatant of the brain increased significantly with age. When the 24-27 month and 34-37 month old rats were compared, the ratios of the total activities of liver beta-N-glucosaminidase and brain acid DNase in the supernatant and the specific activities of brain beta-N-glucosaminidase in the microsomal fraction increased significantly.
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PMID:Changes in intracellular activities of lysosomal enzymes in tissues of rats during aging. 22 57

Studies were undertaken on the turnover of ribosomal RNA and on ribonuclease activity in the liver of the pregnant rat in an attempt to explain the accumulation of liver RNA which occurs during the latter half of pregnancy. Between the 15th and 20th day of gestation the rate constant of degradation, biological half-life and daily rate of synthesis of ribosomal RNA were calculated to be 0.0887, 7.81 days and 6.21 mg per liver per 100g body weight respectively. Corresponding values in non-pregnant rats were 0.123, 5.68 days and 3.47 mg per liver per 100g body weight. The increase in RNA was therefore associated with an increase in its rate of synthesis and a decrease in its rate of breakdown. From the 14th day of pregnancy there was a decrease in alkaline ribonuclease activity and a marked increase in the level of alkaline ribonuclease inhibitor. The activity of acid ribonuclease was found to increase and that of acid phosphatase to decrease during this period.
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PMID:Ribosomal RNA turnover and the level of ribonuclease activity in the liver of the pregnant rat. 23 89

Oral administration of one dose of 6.0 and 12.0 mg retinol for one day significantly increased percentage free activities of protease (cathepsins), cathepsin B1 and acid ribonuclease, whereas feeding of one dose of 1.5 mg retinol for one day did not release the above enzymes in younger rats. However, feeding of 1.5, 6.0 and 12.0 mg retinol daily for two days did not significantly increased the percentage free activities of these lysosomal enzymes except that of acid ribonuclease which was still increased in young rats fed 12.0 mg retinol. Retinol feeding either for one day or two days did not affect the release of acid phosphatase and aryl sulphatase in young rats. Retinol inhibited in vitro the activities of protease (cathepsins) and cathepsin B1.
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PMID:Hepatic lysosomal enzymes in young rats fed retinol. 44 49

Cytochemical methods are used to examine the distribution and localization of acid phosphatase, non-specific esterase, ribonuclease and peroxidase activity in the walls of the spores of the heterosporous Marsileaceae before and during germination. In the quiescent spore, the principal activity is associated with the perine layer of the wall and the intine, with some activity in the outer, gelatinous wall layer, but none in the exine. The microspores of Marsilea and Pilularia have non-specific esterase activity concentrated in the intine inthe immediate vicinity of the germinal site; that is, above the position of the future male gametangia. The enzymes are not leached from the wall during hydration of the spores, although ribonuclease is redistributed during imbibition with a high concentration of activity remaining in or around the germinal site. The wall enzymes occur together with PAS-reactive and acidic carbohydrates, lipids, and in the microspore perine, beta-lectins. Following the enzyme pattern, the beta-lectins are found to be concentrated in the region of the germinal site. beta-Lectin activity is absent from the megaspore wall. Acidic carbohydrates are confined to the gelatinous wall layer and this layer also binds concanavalin A. In contrast to what has been found for other plant cells, the spore-wall beta-lectins are not water-labile; the activity is not significantly diminished after hydration. This surprising stability suggests that these molecules, together with the enzymes, may be retained in position in the wall by the waterproof overlay of lipid. From the evidence of preliminary developmental studies, it appears that the enzymes associated with the perine layer of the wall originate in the sporophytic tapetal periplasmodium and inclusion of the activity is concurrent with wall differentiation, while the activity associated with the intine is derived from the gametophyte. It is possible, however, in the megaspore at least, that the distribution of the activity may to some extent be influenced by a system of exine channels which communicates between the two domains of the wall during sporogenesis. No definite information is obtained concerning the utility of the enzymes and associated molecules in the life of the spore. Acting separately or in co-operation, their role could conceivably be connected with one or more of four processes; wall differentiation, gametophyte nutrition, gametophyte protection or reproduction. Each of these possibilities is discussed.
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PMID:Developmental mechanisms in heterospory: cytochemical demonstration of spore-wall enzymes associated with beta-lectins, polysaccharides and lipids in water ferns. 52 75

A comparative study was made of the total lysosomal enzyme activity found in homogenates of normal ectocervical squamous epithelium and squamous carcinoma of this epithelium. The activities of acid phosphatase, beta-glucuronidase, cathepsin D and acid ribonuclease were higher in carcinoma tissue than in normal tissue. The most important observation made was with regard to the distribution of enzyme activity in homogenates. In carcinoma homogenates most of the enzyme activity was detected in the lysosomal fractions, whereas in controls the activity was predominantly found in the cytosol fractions. No histochemical and electron microscopical techniques were used in this study. Because it was possible to sediment the enzyme activity and to demonstrate latency, these can be referred to as lysosomal enzymes with certainty.
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PMID:[A comparism between lysosomal enzyme activity in normal ectocervical squamous epithelium and squamous carcinoma of the ectocervix]. 56 9


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