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

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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)

Two forms of the yeast 5.8S rRNA are generated from a large precursor by distinct processing pathways. Cleavage at site A3 is required for synthesis of the major, short form, designated 5.8S(S), but not for synthesis of the long form, 5.8S(L). To identify components required for A3 cleavage, a bank of temperature-sensitive lethal mutants was screened for those with a reduced ratio of 5.8S(S):5.8S(L). The pop1-1 mutation (for processing of precursor RNAs) shows this phenotype and also inhibits A3 cleavage. The pre-rRNA processing defect of pop1-1 strains is similar to that reported for mutations in the RNA component of RNase MRP; we show that a mutation in the RNase MRP RNA also inhibits cleavage at site A3. This is the first site shown to require RNase MRP for cleavage in vivo. The pop1-1 mutation also leads to a block in the processing of pre-tRNA that is identical to that reported for mutations in the RNA component of RNase P. The RNA components of both RNase MRP and RNase P are underaccumulated in pop1-1 strains at the nonpermissive temperature, and immunoprecipitation demonstrates that POP1p is a component of both ribonucleoproteins. The POP1 gene encodes a protein with a predicted molecular mass of 100.5 kD and is essential for viability. POP1p is the first protein component of the nuclear RNase P or RNase MRP for which the gene has been cloned.
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PMID:The POP1 gene encodes a protein component common to the RNase MRP and RNase P ribonucleoproteins. 792 42

RNase MRP is a ribonucleoprotein endoribonuclease that has been shown to cleave mitochondrial primer RNA sequences from a variety of sources. Most of the RNase MRP activity is found in the nucleus where it plays a role in the processing of 5.8S rRNA. A temperature-conditional point mutation in the yeast RNA component of the enzyme has been identified. This mutation results in a loss of normal rRNA processing at the nonpermissive temperature while cellular levels of the RNA component of RNase MRP remain stable. High-copy suppressor analysis of this point mutation was employed to identify interacting proteins. A unique suppressor, termed SNM1 (suppressor of nuclear mitochondrial endoribonuclease 1), was identified repeatedly. The SNM1 gene was localized to the right arm of chromosome IV, directly adjacent to the SNF1 gene, and it contains an open reading frame encoding a protein of 198 amino acids. The protein contains a leucine zipper motif, a zinc-cluster motif, and a serine/lysine-rich tail. The gene was found to be essential for viability in a yeast cell, consistent with it being a protein component of the RNase MRP ribonucleoprotein complex. Recombinant SNM1 protein binds RNA in both gel retardation and Northwestern assays. Antibodies raised against bacterially expressed proteins identified four separate species in yeast whole cell extracts. Antibodies directed against the SNM1 protein immunoprecipitated RNase MRP RNA from whole-cell extracts without precipitating the structurally and functionally related RNase P RNA. We propose that the SNM1 protein is an essential and specific component of the RNase MRP ribonucleoprotein complex, the first unique protein of this complex to be identified.
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PMID:Characterization of a unique protein component of yeast RNase MRP: an RNA-binding protein with a zinc-cluster domain. 795 20

Several enzymatic and chemical reagents were used to probe the secondary structure of Saccharomyces cerevisiae nuclear RNase P RNA in the presence and absence of its protein components. Double-stranded regions were detected with RNase V1 and single-stranded regions with RNase ONE (Escherichia coli RNase I). Nucleotides not paired at Watson-Crick positions were monitored with dimethyl sulfate, kethoxal, and 1-cyclohexyl-3-[2-(N-methylmorpholinio)ethyl]carbodiimide p-toluenesulfonate. The results supported most aspects of the previously proposed, phylogenetically-derived RNA secondary structure, although minor refinements allowed incorporation of both the biochemical and phylogenetic data. Digestion of the RNase P protein(s) with proteinase K gave enhanced reactivities to structure probes at selected positions, indicating regions of the RNA made inaccessible by the presence of the protein subunit(s). The regions of RNA protected in the yeast nuclear holoenzyme were considerably more extensive than that seen in the Escherichia coli holoenzyme, consistent with the observation that the protein moiety generally comprises a larger percentage of the RNase P holoenzyme in eukaryotes than in eubacteria.
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PMID:Structure-sensitive RNA footprinting of yeast nuclear ribonuclease P. 811 Jul 80

We show that the Th/To ribonucleoprotein is defined by (i) the co-immunoprecipitation of two RNAs, (ii) the co-immunoprecipitation of four major polypeptides and (iii) the quantitative immune recognition of both RNase P and RNase MRP. No serum was found that recognizes either one of these two enzymes exclusively. The specific co-immunoprecipitation of RNase MRP and RNase P by all Th/To ribonucleoprotein autoantibodies indicates that the anti-Th/To autoimmune response is directed against both enzymes in a quantitatively indistinguishable manner. Thus the Th/To ribonucleoprotein is defined by RNase P and RNase MRP.
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PMID:Definition of the Th/To ribonucleoprotein by RNase P and RNase MRP. 823 91

RNase MRP and RNase P ribonucleoproteins are structurally and functionally similar across a large evolutionary distance. To better characterize possible complex interrelationships between these two enzymes, we have employed the fission yeast Schizosaccharomyces pombe. Unlike Saccharomyces cerevisiae, S. pombe is believed to harbour only one genetic locus for the RNA component of RNase P and does not contain a known mitochondrially encoded RNase P RNA. We have identified the single nuclear gene for the RNA component of RNase MRP in S. pombe, mrp-1, by homology to vertebrate RNase MRP RNAs. The mrp-1 gene encodes an RNA of maximum mature length 400 nucleotides that shares a high degree of identity, in evolutionarily conserved regions, to both vertebrate RNase MRP RNAs and S. pombe RNase P RNA. Disruption of mrp-1 in the diploid strain SP826 and sporulation of tetrads resulted in a 2 dead:2 viable segregation, consistent with the gene being essential. Lethality is rescued by a plasmid-borne copy of mrp-1. Partially purified ribonucleoprotein RNase MRP activity correctly and efficiently processed all previously characterized heterologous mitochondrial RNA substrates. The compact mitochondrial genome of S. pombe contains sequence elements with > 50% identity to mammalian D-loop CSBI and CSBII elements. The identification of mrp-1 in S. pombe should facilitate not only comparisons between the related ribonucleoproteins RNase MRP and RNase P, but should also provide an opportunity for genetic elucidation of RNase MRP function in a situation reflective of the animal kingdom.
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PMID:Schizosaccharomyces pombe RNase MRP RNA is homologous to metazoan RNase MRP RNAs and may provide clues to interrelationships between RNase MRP and RNase P. 855 96

We report a detailed evolutionary study of the RNase P- and RNase MRP- associated RNAs. The analyses were performed on all the available complete sequences of RNase MRP (vertebrates, yeast, plant), nuclear RNase P (vertebrates, yeast), and mitochondrial RNase P (yeast) RNAs. For the first time the phylogenetic distance between these sequences and the nucleotide substitution rates have been quantitatively measured.The analyses were performed by considering the optimal multiple alignments obtained mostly by maximizing similarity between primary sequences. RNase P RNA and MRP RNA display evolutionary dynamics following the molecular clock. Both have similar rates and evolve about one order of magnitude faster than the corresponding small rRNA sequences which have been, so far, the most common gene markers used for phylogeny. However, small rRNAs evolve too slowly to solve close phylogenetic relationships such as those between mammals. The quicker rate of RNase P and MRP RNA allowed us to assess phylogenetic relationships between mammals and other vertebrate species and yeast strains. The phylogenetic data obtained with yeasts perfectly agree with those obtained by functional assays, thus demonstrating the potential offered by this approach for laboratory experiments.
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PMID:The evolution of the RNase P- and RNase MRP-associated RNAs: phylogenetic analysis and nucleotide substitution rate. 866 Apr 29

RNase P is a ribonucleoprotein endoribonuclease responsible for the 5' maturation of precursor tRNAs in all organisms. While analyzing mutations in conserved positions of the yeast nuclear RNase P RNA subunit, significant accumulation of an aberrant RNA of approximately 193 nucleotides was observed. This abundant RNA was identified as a 3'extended form of the 5.8S rRNA. This strain also displays a slightly elevated level of other rRNA processing intermediates with 5-ends at processing site A2 in the internal transcribed spacer 1 (ITS1) region of the rRNA primary transcript. To test whether pre-rRNA in the region of ITS1/5.8S/ITS2 is a substrate for RNase P in vitro, nuclear RNase P was partially purified to remove contaminating nucleases. Cleavage assays were performed using an rRNA substrate transcribed in vitro which includes the 5.8S region and its surrounding processing sites in ITS1 and ITS2. Discrete cleavages of this rRNA substrate were coincident with the peak fractions of nuclear RNase P, but not with fractions corresponding to mitochondrial RNase P or ribonuclease MRP RNA. The cleavage activity is sensitive to treatment with micrococcal nuclease, also consistent with an activity attributable to RNase R The strong RNase P cleavage sites were mapped and their possible relationships to steps in the rRNA processing pathway are considered. These observations suggest an intimate relationship between the processes of tRNA and rRNA maturation in the eukaryotic nucleus.
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PMID:An RNase P RNA subunit mutation affects ribosomal RNA processing. 877 95

RNase mitochondrial RNA processing enzyme (MRP) is a nucleolar ribonucleoprotein particle that participates in 5.8S ribosomal RNA maturation in eukaryotes. This enzyme shares a polypeptide and an RNA structural motif with ribonuclease P (RNase P), a nuclear endoribonuclease originally described in the nucleus that processes RNA transcripts to generate their mature 5' termini. Both enzymes are also located in mitochondria. This report further characterizes the relationship between RNase MRP and RNase P. Antisense affinity selection with biotinylated 2'-O-methyl oligoribonucleotides and glycerol gradient fractionation experiments demonstrated that small subpopulations of RNase MRP and RNase P associate with each other in vivo in macromolecular complex, possibly 60-80S preribosomes. This latter notion was supported by fluorescence in situ hybridization experiments with antisense oligonucleotides that localized that RNA components of RNase MRP and RNase P to the nucleolus and to discrete cytoplasmic structures. These findings suggest that small subpopulations of RNase MRP and RNase P are physically associated, and that both may function in ribosomal RNA maturation or ribosome assembly.
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PMID:Association of RNase mitochondrial RNA processing enzyme with ribonuclease P in higher ordered structures in the nucleolus: a possible coordinate role in ribosome biogenesis. 887 59

RNase MRP is a ribonucleoprotein enzyme with a structure similar to RNase P. It is required for normal processing of precursor rRNA, cleaving it in the Internal Transcribed Spacer 1.
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PMID:RNase MRP and rRNA processing. 890 90

RNase MRP cleaves the yeast pre-rRNA at a site in internal transcribed spacer 1 (ITS1) and this cleavage can be reproduced in vitro by the highly purified enzyme. Two protein components (Pop1p and Pop2p) have been identified which are common to yeast RNase MRP and RNase P. Moreover, purified RNase P can also cleave the pre-rRNA substrate in vitro, underlining the similarities between these particles. Genetic evidence suggests that RNase MRP functionally interacts with the snoRNPs which are required for other pre-RNA processing reactions.
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PMID:Genetic and biochemical analyses of yeast RNase MRP. 890 91


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