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)

By using a suckling mouse assay, heat-stable enterotoxin (ST) was purified from the culture filtrate of Yersinia enterocolitica isolated from a diarrheal patient. The purification procedures involve ultrafiltration with an Amicon HIP-10 hollow fiber, ethanol fractionation, protamine sulfate treatment, diethylaminoethyl-Sephacel and hydroxylapatite column chromatographies, and Sephacryl S-200 superfine gel filtration. About 408-fold purification was achieved, with a yield of 12.0%. The minimal effective dose of purified ST was about 110 ng in the suckling mouse assay. The molecular weight of purified ST was 9,000 by Sephadex G-100 superfine gel filtration. The purified ST was stable to heating (100 degrees C for 20 min, 121 degrees C for 20 min) and did not lose its toxicity after treatment with protease, trypsin, lipase, phospholipase C, ribonuclease, deoxyribonuclease, beta-glucosidase, and neuraminidase. The purified ST was separated by isoelectric focusing into two active fractions, with pI's of 3.29 (ST-1) and 3.00 (ST-2), respectively. Antiserum from guinea pigs immunized with the purified ST neutralized the activity of both Y. enterocolitica ST and Escherichia coli ST.
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PMID:Partial purification and characterization of heat-stable enterotoxin produced by Yersinia enterocolitica. 721 60

The recently developed protein A-gold technique for the detection of intracellular antigenic sites on thin sections was utilized to localize nine different secretory proteins in the rat exocrine pancreas. Amylase, chymotrypsinogen, trypsinogen, lipase, elastase, carboxypeptidases A and B, RNase and DNase, were detected at the level of the rough endoplasmic reticulum, the Golgi area, and the zymogen granules of the acinar cells, as well as in the acinar lumen. A quantitative evaluation of the labeling showed that its intensity was not identical for all enzymes studied nor in all cellular compartments analyzed. An increasing gradient of the labeling from the rough endoplasmic reticulum to the Golgi and to the zymogen granules was found for amylase, carboxypeptidases A and B, chymotrypsinogen, trypsinogen, and RNase, while a comparable low degree of labeling in the Golgi apparatus and in the zymogen granules was observed for DNase, lipase, and elastase. These results suggest that the nine enzymes are processed through the same intracellular compartments, but that they may be concentrated to different degrees in the zymogen granules before being released in the acinar lumen.
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PMID:Quantitative immunocytochemical localization of pancreatic secretory proteins in subcellular compartments of the rat acinar cell. 735 12

Although human milk generally contains higher levels of enzymes than bovine milk, little definitive information is available concerning their role or significance. The enzyme levels in human milk as compared to bovine milk and levels in human colostrum versus normal milk are summarized. The few most widely studied human milk enzymes are discussed in more detail. Evidence is presented to support the views that 1) lipoprotein lipase and ribonuclease are probably spilled into the milk from the blood; 2) lysozyme is spilled from the secretory epithelial cells; 3) lactate and malate dehydrogenases, glucose-6-phosphate dehydrogenase, and lactose synthetase are synthesized in the mammary gland in response to hormonal stimuli; and 4) bile salt stimulated lipase, diastase, protease, and lysozyme are present in sufficient quantities to aid infants in growth and nutrition. Consideration must be given to standardizing the various enzyme assay procedures and activity units so that meaningful comparisons between various studies could be made.
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PMID:Role and significance of enzymes in human milk. 740 88

The synthesis and secretion of proteins during development of the pancreas was analyzed using two-dimensional gel electrophoresis. The pattern of synthesis of the total proteins of the pancreas was found to change very little from 14 to 18 d gestation. In addition, the protein synthetic pattern of the embryonic pancreas was very similar to the protein patterns of several other embryonic tissues (gut, lung, and mesenchyme). Between 18 d gestation and the adult stage, the synthesis of the majority of protein species fades as the synthesis of the secretory (pro)enzymes becomes dominant. Thus, the terminal differentiation of the pancreas appears to involve the dominant expression of a limited set of genes (coding, in part, for the digestive [pro]enzymes) while the pattern of expression of the remaining domain remains relatively unchanged. Many of the secretory (pro)enzymes were identified and their synthesis during development was monitored. The synthesis of several secretory proteins was detected between 15 and 18 d gestation (e.g., amylase and chymotrypsinogen), whereas the synthesis of others was not detected until after 18 d gestation (i.e., trypsinogen, ribonuclease, proelastase, and lipase). Between 18 d gestation and the adult stage, the synthesis of the digestive (pro)enzymes increases to > 90% of pancreatic protein synthesis. The secretion of digestive (pro)enzymes was detected as early as 15 d gestation. The selective release of a second set of proteins was detected in the early embryo. These proteins are not detected in the adult pancreas or in zymogen granules but are also released by several other embryonic tissues. The function of this set of proteins is unknown.
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PMID:Proteins synthesized and secreted during rat pancreatic development. 741 Apr 79

Changes in serum and intrapancreatic enzyme content and protein synthesis in pancreas were studied in acute oedematous pancreatitis (AOP). Male Wistar rats (n = 111) were divided into 2 groups, controls with a sham operation and those with AOP. Serum amylase levels rose immediately after the procedure causing AOP and then fell gradually, while serum lipase and ribonuclease levels remained higher than control values over 48 h. (p < 0.05, 0.01). Serum deoxyribonuclease (DNase) II levels were unchanged. Intrapancreatic enzyme levels were scarcely affected by AOP. 3H-leucine uptake into pancreatic tissue of rats with AOP was decreased throughout the study (p < 0.001), but some protein synthesis continued. Intrapancreatic enzyme contents are maintained despite diffusion into the blood because the pancreas retain its ability to synthesize enzymes.
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PMID:Pancreatic exocrine enzymes and intrapancreatic protein synthesis in acute oedematous pancreatitis. 752 55

The growth of group A human, bovine, equine and porcine rotaviruses were enhanced by pretreatment of virus with pancreatin, trypsin, protease, alkaline phosphatase or pepsin and incorporation of these enzymes in maintenance medium. In contrast, alpha-amylase or lipase inhibited the growth of equine and porcine rotaviruses. The other enzymes, adenosine deaminase, lactase, lysozyme, ribonuclease or triose-phosphate isomerase gave little or no change in the growth of all four rotaviruses.
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PMID:Effect of enzymes on the growth of human and animal rotaviruses. 754 24

The effect of prolactin on the digestive potency of the acinar pancreas was examined in pituitary-grafted hyperprolactinemic mice, because our previous experiment showed that a marked proliferation of pancreatic acinar cells was induced by pituitary grafting in mice. To know whether the digestive function is modified, the tissue contents of pancreatic digestive enzymes, such as chymotrypsin, lipase alpha-amylase and ribonuclease, were measured in the hyperprolactinemic mice. Pituitary grafting significantly increased the contents of chymotrypsin and lipase in the pancreas on day 12 after the operation without affecting intake of food, when compared to those in the sham-operated controls. On day 30, however, the differences between pituitary-grafted and control mice were no more discernible. Thus, the digestive enzyme activities are easily modified soon after the increase of circulating prolactin level. This effect of prolactin on the function of the pancreas may be responsible for "homeorhetic" control of nutrients during lactation. In another set of experiments in adrenalectomized-castrated or castrated mice, pituitary grafting induced an increase in the weight of the pancreas. In addition, adrenalectomy in combination with castration did not alter the pancreatic contents of chymotrypsin and lipase but decreased the amylase content. These results taken together seem to indicate that the effect of prolactin on the exocrine pancreas is not mediated by gonadal and adrenal steroid hormones.
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PMID:Modification of pancreatic digestive function by pituitary grafting in mice. 765 48

Hormone-sensitive lipase expression was studied in the human colon adenocarcinoma cell line, HT29. Diacylglycerol lipase and cholesterol esterase [corrected] activities in HT29 cells were inhibited by known inhibitors of hormone-sensitive lipase (diethyl-p-nitrophenyl phosphate, NaF and HgCl2) to the same extent as in human adipocytes. A polyclonal antiserum directed against rat hormone-sensitive lipase inhibited 89% of HT29 cell lipase activity. HT29 hormone-sensitive lipase was the same size as the adipocyte enzyme as was its mRNA. Complete homology between mRNA sequences in HT29 and adipocyte was demonstrated using ribonuclease protection assay. These data are consistent with the expression of a protein closely related, if not identical, to the enzyme expressed in human adipose tissue. HT29 is the first human cell line where hormone-sensitive lipase expression has been shown.
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PMID:Expression of hormone-sensitive lipase in the human colon adenocarcinoma cell line HT29. 769 73

The genetic defect causing cholesteryl ester storage disease (CESD) has been investigated in an 11 year old patient. Lysosomal acid lipase (LAL) activity in cultured skin fibroblasts and peripheral lymphocytes was reduced to approximately 3% and approximately 4% of controls, respectively. The parents had low acid lipase activity in white blood cells. Using the polymerase chain reaction followed by ribonuclease protection assay, we examined the LAL mRNA from the liver of the affected patient to identify small deletion, abnormal splicing or missense mutation. Using this technique we identified a LAL mRNA cytosine to thymidine transition in position 923, predicting a missense substitution of tyrosine for histidine in codon 274. By differential oligonucleotide hybridization on an amplified white blood cell mRNA, the cytosine to thymidine transition was investigated in the family members and in the population. No normal mRNA coding for cytosine in position 923 was detectable in the propositus and mRNA from the phenotypically normal parents coded for both cytosine and thymidine. This can only be accounted for by assuming that the propositus is homozygote for the mutation. The mutation, segregated in the family with levels of acid lipase activity in white blood cells, was not detected in mRNA from 60 normal subjects. These data provide evidence that the cytosine to thymidine transition in position 923 in LAL mRNA causes the clinical expression of CESD in this patient. The predicted substitution of tyrosine for histidine in codon 274 suggests that this amino acid is involved in the structure-function of the lysosomal acid lipase enzyme.
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PMID:A histidine to tyrosine replacement in lysosomal acid lipase causes cholesteryl ester storage disease. 783 18

The in vitro effects of GH on human adipose tissue lipoprotein lipase (LPL) activity and messenger ribonucleic acid (mRNA) levels were studied using a tissue incubation technique. After preincubation for 3 days, abdominal sc adipose tissue pieces were exposed to cortisol (1000 nmol/L) for 3 days to induce LPL activity. Addition of GH (50 micrograms/L) to the cortisol-containing medium during the last 24 h (day 6) caused a decrease by 84 +/- 4% (P < 0.01) in heparin-releasable LPL activity and by 65 +/- 4% (P < 0.01) in total LPL activity. Moreover, the heparin-releasable fraction was reduced from 42% of the total LPL activity with cortisol alone to 17% when both GH and cortisol were present in the incubation medium during the last 24 h (P < 0.01). The reduction in LPL activity in response to GH was not accompanied by a decrease in the level of LPL mRNA measured by a solution hybridization ribonuclease protection assay. In adipose tissue incubated in the control medium for 6 days, the addition of GH alone during the last 24 h caused an insignificant decrease in heparin-releasable LPL activity. Low control activities limited the scope for further decrease. It is concluded that GH counteracts the potent stimulatory effect of glucocorticoids on LPL activity without affecting LPL mRNA levels. Therefore, the inhibition of LPL activity by GH probably occurs during translation and/or posttranslational processing of the enzyme, and the mechanism may involve a decreased channeling of the lipase to the cell surface.
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PMID:Growth hormone inhibits lipoprotein lipase activity in human adipose tissue. 788 53


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