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)

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 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

RNase P, the enzyme response for 5'-end processing of tRNAs and 4.5S RNA, has been extensively characterized from E. coli. The RNA component of E. coli RNase P, without the protein, has the enzymatic activity and is the first true RNA enzyme to be characterized. RNase P and MRP are two distinct nuclear ribonucleoprotein (RNP) particles characterized in many eukaryotic cells including human, yeast and plant cells. There are many similarities between RNase P and MRP. These include: (1) sequence specific endonuclease activity; (2) homology at the primary and secondary structure levels; and (3) common proteins in both the RNPs. It is likely that RNase P and MRP originated from a common ancestor.
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PMID:Structural and functional similarities between MRP and RNase P. 890 92

Ribonuclease P (RNase P) is a ribonucleoprotein responsible for the endonucleolytic cleavage of the 5'-termini of tRNAs. Ribonuclease MRP (RNase MRP) is a ribonucleoprotein that has the ability to cleave both mitochondrial RNA primers presumed to be involved in mitochondrial DNA replication and rRNA precursors for the production of mature rRNAs. Several lines of evidence suggest that these two ribonucleoproteins are related to each other, both functionally and evolutionarily. Both of these enzymes have activity in the nucleus and mitochondria. Each cleave their RNA substrates in a divalent cation dependent manner to generate 5'-phosphate and 3'-OH termini. In addition, the RNA subunits of both complexes can be folded into a similar secondary structure. Each can be immunoprecipitated from mammalian cells with Th antibodies. In yeast, both have been found to share at least one common protein. This review will discuss some of the recent advances in our understanding of the structure, function and evolutionary relationship of these two enzymes in the yeast, Saccharomyces cerevisiae.
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PMID:The yeast, Saccharomyces cerevisiae, RNase P/MRP ribonucleoprotein endoribonuclease family. 890 93

The eukaryotic endonucleases RNase P and RNase MRP require both RNA and protein subunits for function. Even though the human RNase P and MRP RNAs were previously characterized, the protein composition of the particles remains unknown. We have identified a human a Caenorhabditis elegans sequence showing homology to yPop1, a protein subunit of the yeast RNase P and MRP particles. A cDNA containing the complete coding sequence for the human protein, hPop1, was cloned. Sequence analysis identifies three novel sequence motifs, conserved between the human, C. elegans and yeast proteins. Affinity-purified anti-hPop1 antibodies recognize a single 115 kDa protein in HeLa cell nuclear extracts. Immunoprecipitations with different anti-hPop1 antibodies demonstrate an association of hPop1 with the vast majority of the RNase P and MRP RNAs in HeLa cell nuclear extracts. Additionally, anti-hPop1 immunoprecipitates possess RNase P enzymatic activity. These results establish hPop1 as the first identified RNase P and MRP protein subunit from humans. Anti-hPop1 antibodies generate a strong nucleolar and a weaker homogeneous nuclear staining in HeLa cells. A certain class of autoimmune patient serum precipitates in vitro-translated hPop1. hPop1 is therefore an autoantigen in patients suffering from connective tissue diseases.
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PMID:hPop1: an autoantigenic protein subunit shared by the human RNase P and RNase MRP ribonucleoproteins. 891 71

RNase MRP is a ribonucleoprotein (RNP) particle which is involved in the processing of pre-rRNA at site A3 in internal transcribed spacer 1. Although RNase MRP has been analysed functionally, the structure and composition of the particle are not well characterized. A genetic screen for mutants which are synthetically lethal (sl) with a temperature-sensitive (ts) mutation in the RNA component of RNase MRP (rrp2-1) identified an essential gene, POP3, which encodes a basic protein of 22.6 kDa predicted molecular weight. Over-expression of Pop3p fully suppresses the ts growth phenotype of the rrp2-1 allele at 34 degrees C and gives partial suppression at 37 degrees C. Depletion of Pop3p in vivo results in a phenotype characteristic of the loss of RNase MRP activity; A3 cleavage is inhibited, leading to under-accumulation of the short form of the 5.8S rRNA (5.8S(S)) and formation of an aberrant 5.8S rRNA precursor which is 5'-extended to site A2. Pop3p depletion also inhibits pre-tRNA processing; tRNA primary transcripts accumulate, as well as spliced but 5'- and 3'-unprocessed pre-tRNAs. The Pop3p depletion phenotype resembles those previously described for mutations in components of RNase MRP and RNase P (rrp2-1, rpr1-1 and pop1-1). Immunoprecipitation of epitope-tagged Pop3p co-precipitates the RNA components of both RNase MRP and RNase P. Pop3p is, therefore, a common component of both RNPs and is required for their enzymatic functions in vivo. The ubiquitous RNase P RNP, which has a single protein component in Bacteria and Archaea, requires at least two protein subunits for its function in eukaryotic cells.
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PMID:Pop3p is essential for the activity of the RNase MRP and RNase P ribonucleoproteins in vivo. 902 60


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