Reaction in vitro of some mutants of RNase P with wild-type and temperature-sensitive substrates
1989 (English)In: Journal of Molecular Biology, ISSN 0022-2836, E-ISSN 1089-8638, Vol. 207, no 4, 837-840 p.Article in journal (Other academic) Published
The reaction of wild-type and two mutant derivatives of RNase P have been examined with wild-type and mutant substrates. We show that a mutant derivative of tRNA(Tyr)Su3, tRNA(Tyr)Su3A15, in which the G15.C48(57) base-pair essential for folding of the tRNA moiety is altered, is a temperature-sensitive suppressor in vivo. The precursor to tRNA(Tyr)Su3A15 is cleaved in a temperature-sensitive manner in vitro by RNase P and with a higher Km compared to the precursor to tRNA(Tyr)Su3. The precursor to tRNA(Tyr)Su3A2, another temperature-sensitive suppressor in vivo in which the G2.C71(80) base-pair in the acceptor stem is changed to A2.C71(80), behaves like the precursor to tRNA(Tyr)Su3 in vitro; that is, it is not cleaved in a temperature-sensitive manner. Therefore, there are at least two ways in which a suppressor tRNA can acquire a temperature-sensitive phenotype in vivo. One of the mutant derivatives of RNase P we have tested, rnpA49, which affects the protein cofactor of the enzyme, has a decreased kcat compared to wild-type, which can explain its phenotype in vivo.
Place, publisher, year, edition, pages
1989. Vol. 207, no 4, 837-840 p.
IdentifiersURN: urn:nbn:se:uu:diva-147817DOI: 10.1016/0022-2836(89)90250-7ISI: A1989AD06200017PubMedID: 2474662OAI: oai:DiVA.org:uu-147817DiVA: diva2:400892