Disease relevance of rncS

• Escherichia coli ribonuclease III cleavage sites [1].
• Processing of mRNA by ribonuclease III regulates expression of gene 1.2 of bacteriophage T7 [2].
• Cleavage by RNase III abolishes the capability of adenovirus messenger RNA to direct cell-free synthesis of virus polypeptides [3].
• Bacillus subtilis RNase III cleaves both 5'- and 3'-sites of the small cytoplasmic RNA precursor [4].
• The absB locus of Streptomyces coelicolor encodes a homolog of bacterial RNase III [5].

Psychiatry related information on rncS

• However, low level activity is observed at extended reaction times and high enzyme concentrations, with an estimated catalytic efficiency approximately 15 000-fold lower than that of RNase III [6].

High impact information on rncS

• Extracts prepared from mutants of Escherichia coli deficient in ribonuclease III do not replicate RSF1030 or Col E1 plasmids in vitro [7].
• Role of plasmid-coded RNA and ribonuclease III in plasmid DNA replication [7].
• OOP RNA, produced from multicopy plasmids, inhibits lambda cII gene expression through an RNase III-dependent mechanism [8].
• Thirty-three years later, a glimpse at the ribonuclease III active site [9].
• RNase III endonucleases cleave double-stranded RNA, transforming precursor RNAs into mature RNAs that act in pre-mRNA splicing, RNA modification, translation, gene silencing, and the regulation of developmental timing [9].

Chemical compound and disease context of rncS

• Ethylation interference and hydroxyl radical footprinting were used to identify substrate ribose-phosphate backbone sites that interact with the Escherichia coli RNA processing enzyme, ribonuclease III [10].
• Escherichia coli RNase III cleaves these three high molecular weight T3 RNA polymerase transcripts to discrete RNAs that comigrate in polyacrylamide gel electrophoresis with some of the late T3 RNAs [11].
• A ColE1 plasmid from the Clarke and Carbon collection [Clarke, L. & Carbon, J. (1976) Cell 9, 91-99] that contains a 14.4-kilobase Escherichia coli DNA insert complements the rnc-105 mutation, which destroys the activity of the RNA-processing enzyme RNase III [12].
• The 30 S ribosomal precursor RNA has been prepared from Escherichia coli AB301/105 (RNase III-) labeled with 32-PO4 in the presence of chloramphenicol [13].
• Accurate in vitro cleavage by RNase III of phosphorothioate-substituted RNA processing signals in bacteriophage T7 early mRNA [14].

Biological context of rncS

• The RNase III protein consists of two modules, a approximately 150 residue N-terminal catalytic domain and a approximately 70 residue C-terminal recognition module, homologous with other dsRBDs [15].
• In fact, by preventing N autoregulation, RNase III activates N gene translation at least 200-fold [16].
• Most of these mRNA fragments are destabilized upon polyadenylation with the exception of the RNA species generated by RNase III [17].
• The double-stranded RNA binding domain (dsRBD) is an approximately 65 amino acid motif that is found in a variety of proteins that interact with double-stranded (ds) RNA, such as Escherichia coli RNase III and the dsRNA-dependent kinase, PKR [18].
• A nucleotide sequence from a ribonuclease III processing site in bacteriophage T7 RNA [19].

Anatomical context of rncS

• These observations establish the presence of a RNase III homolog in eukaryotic cells [20].
• We find that these methods, stepwise chromatography on Whatman CF11-cellulose; digestion with Escherichia coli RNase III; and specific inhibition of globin synthesis in vitro in rabbit reticulocyte lysates, are able to distinguish between stable double-stranded RNA and single-stranded RNA in the expected manner [21].
• As observed in an RNase III-deficient strain, processing of the IVS was not required for the production of functional ribosomes [22].
• In an RNase III-deficient strain of E. coli 23S pre-rRNA accumulates unprocessed in 50S ribosomes and in polysomes [23].
• Transient rescue experiments in HeLa cells demonstrated that the cleavage function of the rnc+ gene was necessary for full rescue of vp1080 [24].

Associations of rncS with chemical compounds

• Defining the enzyme binding domain of a ribonuclease III processing signal. Ethylation interference and hydroxyl radical footprinting using catalytically inactive RNase III mutants [10].
• Furthermore, RNase III cleaved the phosphorothioate internucleotide bond with 5' polarity [14].
• Species C3 is also one of the 5' termini of 23S rRNA generated in vitro from larger precursors by the action of purified RNase III [25].
• Specific overexpression and phosphorylation was used to locate the RNase III polypeptide in the standard two-dimensional gel pattern, and to confirm that serine is the phosphate-accepting amino acid [26].
• For RNase III, a Mn(2+) concentration of 1 mM provides optimal activity, while concentrations >5 mM are inhibitory [6].

Physical interactions of rncS

• Multicopy expression of rnc70 could suppress a lethal phenotype of the wild-type rnc allele in a certain genetic background; it could also inhibit the RNase III-mediated activation of lambdaN gene translation by competing for the RNA-binding site of the wild-type endonuclease [27].

Regulatory relationships of rncS

• Polynucleotide phosphorylase of Escherichia coli induces the degradation of its RNase III processed messenger by preventing its translation [28].

Other interactions of rncS

• These results suggest that polynucleotide phosphorylase requires RNase III cleavages to autoregulate the translation of its message [29].
• Some of these 3' extremities result from endonucleolytic cleavages by RNase E and RNase III and from exonucleolytic degradation [17].
• A 240-nucleotide segment encompassing the 16S 3' end contains another RNase III site and the point of presumed RNase P scission at the 5' end of tRNA1Ile, the first tRNA appearing in the 16-23S spacer region of rrnD and rrnX [30].
• RNase III, a double-stranded RNA-specific endonuclease, is proposed to be one of Escherichia coli's global regulators because of its ability to affect the expression of a large number of unrelated genes by influencing post-transcriptional control of mRNA stability or mRNA translational efficiency [27].
• Statistical models, hidden Markov models (HMMs), were created for the RNase HII, III, II and PH and D families as well as a double-stranded RNA binding domain present in RNase III [31].

Analytical, diagnostic and therapeutic context of rncS

• Northern blot, primer extension and S1 analyses indicated that S-CopA did not form a complete duplex with CopT in vivo since bands corresponding to RNase III cleavage products were missing [32].
• Direct deproteinization of the particle yielded 30S RNA, while deproteinization after treatment with a crude RNase III preparation yielded products similar to 23S and 16S RNA [33].
• Molecular cloning of the gene for the RNA-processing enzyme RNase III of Escherichia coli [12].
• In an RNase III-deficient mutant of Escherichia coli, all 23 S ribosomal RNA in ribosomes is present in an unprocessed form with a double-stranded stem at the base of the molecule stable enough to be detected by electron microscopy under conditions where all other secondary structure is denatured [34].
• The RNA processing functions, T4 RNA ligase, T4 polynucleotide kinase, and the host prr gene product appear not to be essential for exon ligation; neither are the host endoribonucleases RNase III, RNase P and RNase E required for intron excision [35].

References