Yeast Mitochondrial RNase P RNA Synthesis Is Altered in an RNase P Protein Subunit Mutant: Insights into the Biogenesis of a Mitochondrial RNA-Processing Enzyme

• DOI: 10.1128/mcb.16.7.3429
• Publication Date: 2015-10-09T00:24:48Z
• Authors: Vilius Stribinskis; Guo-Jian Gao; Pavol Sulo; Yan Li Dang; Nancy C. Martin
• Keywords: RNase MRP; RNase H; RNase PH

Rpm2p is a protein subunit of Saccharomyces cerevisiae yeast mitochondrial RNase P, an enzyme which removes 5' leader sequences from tRNA precursors. Precursor tRNAs accumulate in strains carrying disrupted allele RPM2. The resulting defect synthesis causes petite mutants to form. We report here that alteration the biogenesis Rpm1r, P RNA subunit, another consequence disrupting High-molecular-weight transcripts accumulate, and no mature Rpm1r produced. Transcript mapping reveals smallest accumulated extended on both 3' ends relative Rpm1r. This intermediate other longer are also found as low-abundance RNAs wild-type cells, allowing identification processing events necessary for conversion primary transcript final products. Our data demonstrate directly transcribed with its substrates, met f tRNAPro, promoter located upstream gene suggest portion originates second promoter, between RPM1. tested possibility precursors because deficiency prevents removal downstream tRNAPro. Large RPM1 still missing this tRNA. Thus, inability process cotranscribed does not explain precursor accumulation phenotype. Furthermore, mutant genes suggesting mutations either can lead similar defects. Several models presented.