Lead-ion-induced cleavage of RNase P RNA.
Pb(2+)-induced hydrolysis of RNase P RNAs from Escherichia coli and the thermophilic eubacterium Thermus thermophilus HB8 revealed one prominent site-specific cleavage in the two RNAs and several minor cleavage sites in structurally corresponding regions of both RNAs. Data presented here and in a previous study [Kazakov, S. & Altman, S. (1991) Proc. Natl Acad. Sci. USA 88, 9193-9197] provide evidence for several ubiquitous metal-ion-binding sites in eubacterial RNase P RNA subunits. With the T. thermophilus RNase P RNA, susceptibility to Pb(2+)-induced strand scission at the most prominent site was hypersensitive at the temperature of highest enzyme activity (55 degrees C). Pb2+ hydrolysis at this site was strongly reduced at a temperature of 37 degrees C, where processing is also inefficient. For E. coli RNase P RNA, specific changes in the lead hydrolysis pattern were observed due to the presence of excess tRNA. Thus, Pb(2+)-induced hydrolysis seems suitable to sense different conformations of RNase P RNAs. The T. thermophilus RNase P RNA, in particular, displayed significant processing activity after severe fragmentation by Pb2+, and therefore appears to be suited for reconstituting an active enzyme from RNA subfragments.
Ciesiolka
J
J
Institut für Biochemie, Freie Universität Berlin, Germany.
Hardt
W D
WD
Schlegl
J
J
Erdmann
V A
VA
Hartmann
R K
RK
D001483:Base Sequence; D001665:Binding Sites; D004722:Endoribonucleases / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism*; D004926:Escherichia coli / Q000378:metabolism*; D029968:Escherichia coli Proteins; D006868:Hydrolysis; D007700:Kinetics; D007854:Lead / Q000494:pharmacology*; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D016337:RNA, Catalytic / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism*; D043262:Ribonuclease P; D013816:Thermodynamics; D016963:Thermus thermophilus / Q000378:metabolism*; D014158:Transcription, Genetic
D029968:Escherichia coli Proteins; D016337:RNA, Catalytic; D007854:Lead; D004722:Endoribonucleases; D043262:Ribonuclease P; C470865:ribonuclease P, E coli