Eukaryotic RNase P RNA mediates cleavage in the absence of protein.

ABSTRACT: The universally conserved ribonucleoprotein RNase P is involved in the processing of tRNA precursor transcripts. RNase P consists of one RNA and, depending on its origin, a variable number of protein subunits. Catalytic activity of the RNA moiety so far has been demonstrated only for bacterial and some archaeal RNase P RNAs but not for their eukaryotic counterparts. Here, we show that RNase P RNAs from humans and the lower eukaryote Giardia lamblia mediate cleavage of four tRNA precursors and a model RNA hairpin loop substrate in the absence of protein. Compared with bacterial RNase P RNA, the rate of cleavage (k(obs)) was five to six orders of magnitude lower, whereas the affinity for the substrate (appK(d)) was reduced approximately 20- to 50-fold. We conclude that the RNA-based catalyti

SUBMITTER: Kikovska E 

PROVIDER: S-EPMC1892975 | biostudies-literature | 2007 Feb

REPOSITORIES: biostudies-literature