Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.26.5 (RNase P)
 1,348 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The gene coding for H1 RNA, the RNA component of human RNase P, has been isolated and characterized from a human genomic DNA library. The sequence corresponding to the mature H1 RNA is almost identical to that previously identified using H1 RNA and a cDNA clone corresponding to it. The nucleotide sequence of the genomic clone contains an array of potential transcriptional control elements, some characteristic of transcription by RNA polymerase III and some characteristic of RNA polymerase II, as is also the case for U6 and certain other small stable RNAs. The transcription in vitro of the genomic clone shows that the gene is functional and is transcribed by RNA polymerase III. Southern hybridization analysis indicates that there is very likely only one copy of the gene for H1 RNA in the human genome.
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PMID:Structure and transcription of a human gene for H1 RNA, the RNA component of human RNase P. 230 39

Modified bases were introduced into pre-tRNAs during in vitro RNA synthesis or by chemical modification. These RNAs were used as substrates for the catalytic M1 RNA and the RNase P holoenzyme from Schizosaccharomyces pombe. The synthetic approach permitted the insertion of 100% m7GTP into pre-tRNAs and this resulted in complete inhibition of the specific 5' processing reactions. Partially modified RNAs were obtained by chemical modifications of purines and uridines in the pre-tRNAs. This allowed detailed analyses of specific bases excluded in the products. With pre-tRNA(Ser) and initiator pre-tRNA(Met), strong effects were observed in the T arm and weaker effects in the anticodon stem. Only minor base exclusions were detected in the acceptor stem of pre-tRNA(Ser) and in the D arm of pre-tRNA(Met).
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PMID:Substrate recognition by RNase P and by the catalytic M1 RNA: identification of possible contact points in pre-tRNAs. 234 11

A bank of temperature sensitive (ts-) mutants of Schizosaccharomyces pombe was screened for snRNA expression mutants using an oligodeoxynucleotide that recognizes U2 RNA. One mutant with a novel phenotype was identified that has reduced steady-state levels of the spliceosomal snRNAs U1, U2, U4, U5 and U6. In addition, the mutant exhibits a temperature-dependent accumulation of aberrant U2 and U4 transcripts elongated at their 3' end. The steady-state concentration of the RNA component of RNase P is also reduced in the mutant, whereas the amount of U3 RNA, 7SL RNA, tRNA, rRNA and mRNA are the same as wild-type. Pre-mRNA, pre-tRNA and U6 RNA precursor processing are impaired in the mutant. Genetic analysis demonstrates that the snRNA defects are tightly linked to the ts- growth defect and are recessive. We have named this mutant snm1 to indicate a defect in snRNA maintenance. The data on snm1 suggest that a single trans-acting factor is essential for the maintenance of steady-state levels of several snRNAs and for proper 3' end formation of U2 and U4 RNAs.
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PMID:A mutation in a single gene of Schizosaccharomyces pombe affects the expression of several snRNAs and causes defects in RNA processing. 240 30

The gene for the RNA subunit (M1 RNA) of ribonuclease P from Salmonella typhimurium directs the synthesis of an RNA that can cleave transfer RNA precursor molecules. The mature M1 RNA coded for by Salmonella typhimurium is 375 nucleotides long and has six nucleotide changes in comparison to M1 RNA from Escherichia coli. The regions for promotion and termination of transcription are closely conserved, but adjacent regions of nucleotide sequences show considerable drift.
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PMID:A catalytic RNA and its gene from Salmonella typhimurium. 240 35

The rnpA gene, coding for the protein component of ribonuclease P (RNase P), was allocated to the dnaA region at 83 min of the E. coli K-12 map. This was accomplished through analysis of recombinant pBR322 plasmids, some of which complemented the temperature sensitivity of a strain carrying the rnpA 49 allele and restored the RNA processing activity. Although the temperature sensitivity of a strain carrying the rnp-241 allele could not be complemented by the rnpA+ plasmid, the RNA-processing activity was restored, suggesting that the rnp-241 mutation is allelic with rnpA 49. In this analysis we also found two genes coding for proteins (60 and 50 kDal) of unknown function. The order of the genes located in this region is in the clockwise orientation: rpmH (5.4 kDal; ribosomal protein L34), rnpA (14 kDal; protein component of RNase P), a gene for a 60-kDal protein (inner membrane protein), a gene for a 50-kDal protein, and tnaA. All these genes are expressed in the clockwise orientation. From the DNA sequence of the rnpA gene region a very basic polypeptide with an Mr of 13773 could be deduced. We conclude that this polypeptide is the rnpA gene product, and is the protein component of RNase P. Comparison with previously published data on the transcription of rpmH suggests that the rnpA gene is the second gene in the rpmH operon.
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PMID:Physical mapping and nucleotide sequence of the rnpA gene that encodes the protein component of ribonuclease P in Escherichia coli. 241 31

After purification from extracts of whole cells, M1 RNA, the catalytic subunit of ribonuclease P from Escherichia coli, apparently must undergo a change in conformation before it can function catalytically. The rate of this conformational change is dependent upon the duration of incubation at various temperatures and pH. delta E of the transition at pH 7.5 is approximately 36 kcal/mol. The change in conformation is not sensitive to Mg2+ concentration between 10 and 100 mM. A decrease in A260 of M1 RNA in solution has been observed during the incubation period that potentiates the conformational change at 30 degrees C, but no direct correlation can yet be made to specific structural rearrangements.
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PMID:M1 RNA, the RNA subunit of Escherichia coli ribonuclease P, can undergo a pH-sensitive conformational change. 242 64

The splice junction sequence of td mRNA from T4-infected cells has been determined (5'....GGU-CUA....3') and shown to be identical to that of the RNA ligation product encoded by the cloned gene [Belfort et al. Cell 41 (1985) 375-382]. 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. While these results are consistent with the autocatalytic splicing mechanism demonstrated in vitro [Chu et al. J. Biol. Chem. 260 (1985) 10680-10688], they leave unanswered the question of which protein(s), if any, might stimulate the in vivo reaction. Analysis of the products of the cloned td gene has led to identification of two td-encoded polypeptides, namely a polypeptide corresponding to the exon-I-coding sequence (NH2-TS), and the catalytically active thymidylate synthase (TS). Kinetic and nucleotide sequence data provide evidence that NH2-TS is the product of the primary transcript and that TS is encoded by spliced mRNA. These results suggest that splicing may provide a switch controlling the relative expression of NH2-TS and TS, two proteins with markedly different temporal appearances despite their identical transcriptional and translational start sites.
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PMID:RNA splicing and in vivo expression of the intron-containing td gene of bacteriophage T4. 242 90

M1 RNA, the RNA subunit of ribonuclease P from Escherichia coli, can under certain conditions catalytically cleave precursors to tRNA in the absence of C5, the protein moiety of RNase P. M1 RNA itself is not cleaved during the reaction, nor does it form any covalent bonds with its substrate. Only magnesium and, to a lesser extent, manganese ions can function at the catalytic center of M1 RNA. Several other ions either inhibit the binding of magnesium ion at the active site or function as structural counterions. The reaction rate of cleavage of precursors to tRNAs by M1 RNA is enhanced in the presence of poly-(ethylene glycol) or 2-methyl-2,4-pentanediol. Many aspects of the reaction catalyzed by M1 RNA are compatible with a mechanism in which phosphodiester bond cleavage is mediated by metal ion.
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PMID:Metal ion requirements and other aspects of the reaction catalyzed by M1 RNA, the RNA subunit of ribonuclease P from Escherichia coli. 242 12

The gene defining the catalytic RNA component of RNase P in Bacillus subtilis 168 was cloned into bacteriophage lambda and plasmid vectors. The nucleotide sequence of the gene and its surroundings was determined from the cloned DNA and by directly sequencing or reverse transcribing the RNase P RNA. The B. subtilis RNase P RNA sequence (400-401 nucleotides) is remarkably different from that of Escherichia coli (377 nucleotides) (Reed, R. E., Baer, M. F., Guerrier-Takada, C., Donis-Keller, H., and Altman, S. (1982) Cell 30, 627-636; Sakamoto, H., Kimura, N., Nagawa, F., and Shimura, Y. (1983) Nucleic Acids Res. 11, 8237-8251). At best the two are less than 50% similar in sequence. To verify that the RNase P RNA gene was analyzed, a modified, putative gene was cloned adjacent to a bacteriophage T7 promoter and various transcripts were tested for RNase P activity. The intact gene transcript, but not fragments, showed full activity. Full catalytic activity was restored upon mixing the fragments. The extensive differences between the B. subtilis and E. coli RNase P RNAs precluded full covariance analysis of secondary structure, but phylogenetically consistent foldings for portions of both molecules could be derived.
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PMID:The RNA component of the Bacillus subtilis RNase P. Sequence, activity, and partial secondary structure. 242 26

Until the discovery of catalytic RNAs, first the self-splicing intron in Tetrahymena and then the bacterial RNAse P, cellular enzymes had always seemed to be protein in nature. The recognition that RNA can catalytically make and break phosphodiester bonds simplifies some of the assumptions required of a rudimentary self-replicating entity. Available information on the chemistry of RNA-catalyzed reactions is reviewed, with particular attention to self-splicing introns and tRNA processing by RNase P. An explicit model for a self-replicating RNA is described. The model postulates a nucleotide binding/polymerization site in the RNA, and takes advantage of intrinsic fluidity in RNA higher order structure to dissociate parent and progeny complementary strands.
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PMID:RNA catalysis and the origin of life. 242 41


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