In molecular biology, nuclear ribonuclease P (RNase P) is a ubiquitous endoribonuclease, found in archaea, bacteria and eukarya as well as chloroplasts and mitochondria. Its best characterised enzyme activity is the generation of mature 5′-ends of tRNAs by cleaving the 5′-leader elements of precursor-tRNAs. Cellular RNase Ps are ribonucleoproteins. The RNA from bacterial RNase P retains its catalytic activity in the absence of the protein subunit, i.e. it is a ribozyme. Similarly, archaeal RNase P RNA has been shown to be weakly catalytically active in the absence of its respective protein cofactors.[1] Isolated eukaryotic RNase P RNA has not been shown to retain its catalytic function, but is still essential for the catalytic activity of the holoenzyme. Although the archaeal and eukaryotic holoenzymes have a much greater protein content than the bacterial ones, the RNA cores from all three lineages are homologous—the helices corresponding to P1, P2, P3, P4, and P10/11 are common to all cellular RNase P RNAs. Yet there is considerable sequence variation, particularly among the eukaryotic RNAs.

Nuclear RNase P
Predicted secondary structure and sequence conservation of RNaseP_nuc
Identifiers
SymbolRNaseP_nuc
RfamRF00009
Other data
RNA typeGene; ribozyme
Domain(s)Eukaryota; Bacteria; Archaea
GOGO:0008033 GO:0004526 GO:0030677
SOSO:0000386
PDB structuresPDBe

References

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  1. ^ Tsai, H.Y.; Pulukkunat, D.K.; Woznick, W.K.; Gopalan, V. (2006). "Functional reconstitution and characterization of Pyrococcus furiosus RNase P". PNAS. 103 (44): 16147–16152. Bibcode:2006PNAS..10316147T. doi:10.1073/pnas.0608000103. PMC 1637551. PMID 17053064.

Further reading

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