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

In order to facilitate studies of the assembly and transport of the site-specific RNase mitochondrial RNA processing (MRP) ribonucleoprotein, we have characterized it from Xenopus laevis cells. X. laevis RNase MRP displayed a similar spectrum of cleavage activity to that produced by previously isolated mammalian nuclear enzymes. A 277-nucleotide RNA component of the ribonucleoprotein was identified; the gene for the RNA was isolated, sequenced, and found to be 66 and 63% similar to mouse and human RNase MRP RNAs, respectively. Despite the evolutionary distance from its mammalian counterparts, X. laevis RNase MRP RNA contains five regions of homology to the mammalian RNase MRP RNA. Four of these regions correspond to those previously identified as conserved between RNase MRP and RNase P RNAs; the fifth encompasses nucleotides recently discovered to be sufficient for autoantigen binding. The expression and assembly of Xenopus RNase MRP RNA were examined in frog oocytes and developing embryos. RNase MRP RNA was expressed throughout oogenesis; it started to accumulate at stage I and reached a maximum in stage IV. During embryogenesis RNase MRP RNA expression began to elevate at approximately stage 22 and continued to rise through the swimming tadpole stage. When injected into the nucleus of mature oocytes, the X. laevis RNase MRP RNA gene was expressed accurately, and transcripts were packaged into immunoprecipitable particles.
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PMID:Characterization of a Xenopus laevis ribonucleoprotein endoribonuclease. Isolation of the RNA component and its expression during development. 138 27

We have investigated the subcellular organization of the four human Y RNAs. These RNAs, which are transcribed by RNA polymerase III, are usually found complexed with the Ro autoantigen, a 60-kD protein. We designed 2'-OMe oligoribonucleotides that were complementary to accessible single-stranded regions of Y RNAs within Ro RNPs and used them in fluorescence in situ hybridization. Although all four Y RNAs were primarily cytoplasmic, oligonucleotides directed against three of the RNAs hybridized to discrete structures near the nucleolar rim. We have termed these structures "perinucleolar compartments" (PNCs). Double labeling experiments with appropriate antisera revealed that PNCs are distinct from coiled bodies and fibrillar centers. Co-hybridization with a genomic DNA clone spanning the human Y1 and Y3 genes showed that PNCs are not stably associated with the transcription site for these Y RNAs. Although 5S rDNA was often located near the nucleolar periphery, PNCs are not associated with 5S gene loci. Two additional pol III transcripts, the RNA components of RNase P and RNase MRP, did colocalize within PNCs. Most interestingly, the polypyrimidine tract-binding protein hnRNP I/PTB was also concentrated in this compartment. Possible roles for this novel nuclear subdomain in macromolecular assembly and/or nucleocytoplasmic shuttling of these five pol III transcripts, along with hnRNP I/PTB, are discussed.
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PMID:A perinucleolar compartment contains several RNA polymerase III transcripts as well as the polypyrimidine tract-binding protein, hnRNP I. 753 9

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

Antinuclear antibodies (ANA) represent valuable biomarkers in the diagnosis of systemic sclerosis (SSc) being present in the vast majority of the patients. Besides anti-topoisomerase I, anti-centromere and anti-RNA polymerase III antibodies as the main specificities, several other autoantibodies can be present in SSc patients including autoantibodies targeting the PM/Scl complex (also known as the exosome), U3-RNP/fibrillarin and the Th/To autoantigens. Anti-Th/To antibodies are one of the specificities that reportedly show homogenous nucleolar staining in conventional indirect immunofluorescence (IIF) ANA tests. Almost all protein components of the mitochondrial RNA processing (MRP) and the evolutionarily related RNase P complex have been reported to be the target of anti-Th/To antibodies in systemic autoimmune rheumatic disease (SARD) patients. However, Rpp25, Rpp38 and hPop1 have been described as the main autoantigen.
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PMID:Autoantibodies to the mitochondrial RNA processing (MRP) complex also known as Th/To autoantigen. 2546 81