Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.1.26.3 (
RNase III
)
1,015
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The size of
lysozyme
mRNA from T7-infected E. coli RNase III+ and
RNase III
- strains was analyzed by sucrose gradient sedimentation, dimethylsulfoxide (Me2SO) sucorse gradient sedimentation, and preparative gel electrophoresis. Each technique revealed a similar size distribution of multiple
lysozyme
mRNA's. Analysis by preparative gel electrophoresis of RNA extracted after infection of Escherichia coli Bst (RNase III+) separated
lysozyme
mRNA into six peaks of activity ranging in size from 0.2 x 10(6) to 1.9 x 10(6) daltons. Four well-resolved major peaks of activity were detected, having apparent molecular weights of approximately 0.61 x 10(6), 0.76 x 10(6), 0.92 x 10(6), and 1.3 x 10(6). A broad band of activity, with a molecular weight range from 0.2 x 10(6) to 0.37 x 10(6), was also present, and a sixth peak of activity was sometimes observed that migrates with a mobility corresponding to a molecular weight of 1.9 x 10(6). Judging from their molecular weight as estimated by electrophoresis, most, if not all, of the
lysozyme
mRNA's were polycistronic. The RNA extracted after infection of an
RNase III
- host contained a more heterogeneous collection of
lysozyme
mRNA's. In addition to
lysozyme
mRNA activity on RNAs with molecular weights between 0.2 x 10(6) and 1.9 x 10(6), RNA species with molecular weights estimated at 4 x 10(6) to 5 x 10(6) were also detected. The data indicate that
RNase III
processes at least some of the primary
lysozyme
transcripts. The multiple
lysozyme
mRNA's represent discrete RNA species rather than aggregates because analysis of the size of
lysozyme
mRNA under completely denaturing conditions, in Me2SO, produced a similar size distribution of
lysozyme
mRNAs. Also, treatment of RNA with 90% Me2SO, which separates the strands of a completely double-stranded RNA, did not significantly alter the electrophoretic mobility of the
lysozyme
mRNA.
...
PMID:Effect of RNase III on the size of bacteriophage T7 lysozyme mRNA. 35 3
RNase III
had no positive effect on the translation of bacteriophage T7
lysozyme
mRNA in vivo or in vitro. The time of appearance and quanity of
lysozyme
in T7-infected E. coli BL107, an
RNase III
- strain, and T7-infected E. coli BL15, a nearly isogenic RNase III+ strain, were indistinguishable. Nearly identical patterns of
lysozyme
mRNA activity were obtained when RNA extracted at different times after infection of RNase III+ and
RNase III
- hosts was translated in cell-free extracts of E. coli containing or lacking
RNase III
. Exposure of RNA extracted from T7-infected E. coli BL107 (
RNase III
-) to purified
RNase III
did not increase the
lysozyme
mRNA activity of this RNA. The only result that implied that
RNase III
has a differential effect on the translatability of the
lysozyme
mRNA was the translation of fractionaed RNA from T7-infected E. coli BL107. Translation of the smallest and largest
lysozyme
messages, 0.33 x 10(6) and 4 x 10(6) to 5 x 10(6) daltons, was the most inefficient in
RNase III
- cell-free extracts as compared to RNase III+ cell-free translation. The translation of the most abundant, medium-sized
lysozyme
mRNA between 0.9 x 10(6) and 1.5 x 10(6) daltons was the least affected by the absence of
RNase III
. The existence of a lag between the appearance of
lysozyme
mRNA and the appearance of
lysozyme
in T7 infection was confirmed. In these studies a very rapid method of RNA extraction was used, eliminating the possibility of continued RNA transcription during cell collection and RNA extraction. With this method of analysis, the length of the lag period was established at about 3 min. The possibility that
RNase III
is the controlling element of the lag period was eliminated by these investigations.
...
PMID:Effect of RNase III on efficiency of translation of bacteriophage T7 lysozyme mRNA. 35 4
The Corynebacterium glutamicum R grtA (cgR_2936), grtB (cgR_2934) and grtC (cgR_2933) genes were identified as paralogs encoding glutamine-rich toxic proteins. We also identified a new antisense small RNA AsgR (antisense sRNA for grtA) that overlaps the 3' end of the grtA gene. Single over-expressions of grtA, grtB and grtC resulted in complete inhibition of Escherichia coli cell growth. This growth was rescued by co-expression of AsgR. Similar effects were observed in C. glutamicum, although the toxicities of these proteins were moderate. Inhibition of AsgR transcription resulted in increased levels and prolonged half-lives of grtA, grtB and grtC mRNAs. We also found that the expression levels of grtA, grtB and grtC were increased in an
RNase III
deletion mutant. Primer extension analysis revealed the
RNase III
cleavage site to be in the 3' untranslated region (3'-UTR) of the grtA mRNA. The expression levels of grtA, grtB and grtC were increased after exposure to several stresses, including heat shock, treatment with penicillin G,
lysozyme
or H
2
O
2
. The deletions of grtABC and asgR genes resulted in decreased survival rate under several stresses. These results indicate that GrtABC and AsgR constitute a type I toxin-antitoxin-like system in C. glutamicum.
...
PMID:Glutamine-rich toxic proteins GrtA, GrtB and GrtC together with the antisense RNA AsgR constitute a toxin-antitoxin-like system in Corynebacterium glutamicum. 2953 26