Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.26.3 (RNase III)
 1,015 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Plasmid vectors are described that allow cloning of target DNAs at sites where they will be minimally transcribed by Escherichia coli RNA polymerase but selectively and actively transcribed by T7 RNA polymerase, in vitro or in E. coli cells. Transcription is controlled by the strong phi 10 promoter for T7 RNA polymerase, and in some cases by the T phi transcription terminator. The RNA produced can have as few as two foreign nucleotides ahead of the target sequence or can be cut by RNase III at the end of the target sequence. Target mRNAs can be translated from their own start signals or can be placed under control of start signals for the major capsid protein of T7, with the target coding sequence fused at the start codon or after the 2nd, 11th or 260th codon for the T7 protein. The controlling elements are contained on small DNA fragments that can easily be removed and used to create new expression vectors.
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PMID:Vectors for selective expression of cloned DNAs by T7 RNA polymerase. 331 56

Since the speF-potE operon (pPT71 clone) encoding inducible ornithine decarboxylase (iODC) and polyamine transport potE protein is inducible at acidic pH, a gene encoding a protein involved in the enhancement of expression of the operon was searched for. Using the fused gene containing the upstream sequence of the speF-potE operon and the open reading frame of beta-galactosidase as a reporter gene, a clone (pPTS23) which causes the increase of beta-galactosidase activity at acidic pH was isolated. The clone also increased iODC activity at acidic pH and was identified as a gene encoding RNase III. This is the first example that RNase III increases the translational efficiency of mRNA derived from Escherichia coli gene by cutting the 5'-untranslated region of mRNA.
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PMID:Involvement of ribonuclease III in the enhancement of expression of the speF-potE operon encoding inducible ornithine decarboxylase and polyamine transport protein. 816 35

The double-stranded RNA-specific endoribonuclease III (RNase III) of bacteria consists of an N-terminal nuclease domain and a double-stranded RNA binding domain (dsRBD) at the C-terminus. Analysis of two hybrid proteins consisting of the N-terminal half of Escherichia coli RNase III fused to the dsRBD of the Rhodobacter capsulatus enzyme and vice versa reveals that both domains in combination with the particular substrate determine substrate specificity and cleavage site selection. Extension of the spacer between the two domains of the E. coli enzyme from nine to 20 amino acids did not affect cleavage site selection.
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PMID:Both N-terminal catalytic and C-terminal RNA binding domain contribute to substrate specificity and cleavage site selection of RNase III. 1173 5

Three distinct editosomes, typified by mutually exclusive KREN1, KREN2, or KREN3 endonucleases, are essential for mitochondrial RNA editing in Trypanosoma brucei. The three editosomes differ in substrate endoribonucleolytic cleavage specificity, which may reflect the vast number of editing sites that need insertion or deletion of uridine nucleotides (Us). Each editosome requires the single RNase III domain in each endonuclease for catalysis. Studies reported here show that the editing endonucleases do not form homodimeric domains, and may therefore function as intermolecular heterodimers, perhaps with KREPB4 and/or KREPB5. Editosomes isolated via TAP tag fused to KREPB6, KREPB7, or KREPB8 have a common set of 12 proteins. In addition, KREN3 is only found in KREPB6 editosomes, KREN2 is only found in KREPB7 editosomes, and KREN1 is only found in KREPB8 editosomes. These are the same associations previously found in editosomes isolated via the TAP-tagged endonucleases KREN1, KREN2, or KREN3. Furthermore, TAP-tagged KREPB6, KREPB7, and KREPB8 complexes isolated from cells in which expression of their respective endonuclease were knocked down were disrupted and lacked the heterotrimeric insertion subcomplex (KRET2, KREPA1, and KREL2). These results and published data suggest that KREPB6, KREPB7, and KREPB8 associate with the deletion subcomplex, whereas the KREN1, KREN2, and KREN3 endonucleases associate with the insertion subcomplex.
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PMID:Endonuclease associations with three distinct editosomes in Trypanosoma brucei. 2147 42