Substrate and enzyme determinants for recognition by human mitochondrial RNase P.

ABSTRACT: RNase P enzymes of widely varying architectures recognize the 5'-leader/acceptor-stem junction and the D/T loop-interaction region of precursor tRNAs to direct cleavage to the 5' end of tRNAs. In contrast, human mitochondrial RNase P (mtRNase P) encases the entire tRNA with the aid of the methyltransferase subcomplex TRMT10C-SDR5C1. Here, we performed a kinetic analysis of substrate recognition by mtRNase P using substrate and protein variants. Surprisingly, processing by mtRNase P was found to be more efficient for tRNA precursors with longer 5' extensions and decreased sharply at a leader length of 1 nt. MtRNase P also employs a more rigid "measuring mechanism" for cleavage-site selection than the related single-subunit enzymes, so that even substrates with a G:C base-pair extension of t

SUBMITTER: Hazisllari E 

PROVIDER: S-EPMC12630138 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature