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)

A cell-free system was developed and characterized, which supported RNA release from isolated rat liver cell nuclei. The RNA release in the system seemed to be dependent on the presence of ATP as an evergy source and of dialized cytosol as far as on the temperature level in the incubation mixture. In vitro effects of a number of RNase affectors from cytoplasm and of related exogenous compounds on the RNA release were studied. It was shown that RNase inhibitors such as heparin, PVS and rat liver cytoplasmic RNA were capable to stimulate the RNA release, while the natural inhibitor from liver cytosol failed to influence the RNA relase. Spermidine and PCMB lowered the rate of RNA release from nuclei. The results are discussed in connection with possible role of nuclear RNases and cytoplasmic factors in nucleocytoplasmic transport of RNA.
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PMID:[RNA transport from rat liver cell nuclei in vitro. Release of rapidly labeled RNA from isolated nuclei in a cell-free system in the presence of RNAse affectors]. 74 5

Low concentrations of HgCl(2) were found to induce extensive degradation of ribonucleic acid (RNA) in exponentially growing Escherichia coli cells but not in stationary-phase cells. Whereas 80% of cellular RNA was degraded during 90 min of incubation with 10(-5)m HgCl(2) at 37 C, HgCl(2) caused only slight degradation in stationary cells, even when present at concentrations higher than 5 x 10(-5)m. Inhibition of RNA synthesis occurred at almost the same concentration of HgCl(2) as degradation, and the ability of stationary-phase cells to synthesize RNA was also resistant to HgCl(2). The transition of cells from complete sensitivity to HgCl(2) to a fully insensitive state took place simultaneously with the cessation of growth. p-Chloromercuribenzoate was also found to induce remarkable degradation of RNA. In E. coli Q13, a mutant deficient for ribonuclease I, no degradation of RNA was evident, even in the exponential growth phase. 3'-Mononucleotides but not 5'-mononucleotides were found among the degradation products of cellular RNA. 2',3'-Cyclic mononucleotides were produced when RNA was degraded by the cell-free extracts of the Hg treated cells. Almost complete unmasking of the latent ribonuclease occurred in the particle fraction containing subribosomal particles of the Hg-treated cells. These data suggest that the incubation of exponentially growing E. coli cells with HgCl(2) led to the unmasking of ribonuclease I, which resulted in the extensive degradation of cellular RNA. The activation of ribonuclease by HgCl(2) in the isolated particulate fraction of E. coli K-12 which occurred in vitro suggested the presence of an Hg-sensitive inhibitor for ribonuclease I.
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PMID:Induction by mercuric ion of extensive degradation of cellular ribonucleic acid in Escherichia coli. 489 83