Reaction: Endonucleolytic cleavage of RNA, removing 5'-extranucleotides from tRNA precursor
Other name(s): RNase P
Comments: The enzyme, which is found in archaea, bacteria and eukaryotes, is essential for tRNA processing. It generates 5'-termini or mature tRNA molecules. The enzyme from most sources has been shown to have an RNA chain and a one or more polypeptide chains, but since the RNA chain can act alone as a catalyst in vitro the enzyme should be considered to be a ribozyme [1,2]. Human mitochondrial RNase P has been shown to be a protein that does not require RNA for activity [3]. Spinach chloroplast RNase P has also been shown to function without an RNA component [4].
Links to : BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:
References:
1. Kikovska, E., Svard, S.G. and Kirsebom, L.A. Eukaryotic RNase P RNA mediates cleavage in the absence of protein. Proc. Natl. Acad. Sci. USA 104 (2007) 2062-2067. [PMID: 17284611]
2. Guerrier-Takada, C., Gardiner, K., Marsh, T., Pace, N. and Altman, S. The RNA moiety of ribonuclease P is the catalytic subunit of the enzyme. Cell 35 (1983) 849-857. [PMID: 6197186]
3. Holzmann, J., Frank, P., Loffler, E., Bennett, K.L., Gerner, C. and Rossmanith, W. RNase P without RNA: identification and functional reconstitution of the human mitochondrial tRNA processing enzyme. Cell 135 (2008) 462-474. [PMID: 18984158]
4. Thomas, B.C., Li, X. and Gegenheimer, P. Chloroplast ribonuclease P does not utilize the ribozyme-type pre-tRNA cleavage mechanism. RNA 6 (2000) 545-553. [PMID: 10786845]