RNase Mitochondrial RNA Processing Cleaves RNA from the Rat Mitochondrial Displacement Loop at the Origin of Heavy‐Strand DNA Replication

Abstract

Ribonuclease mitochondrial RNA processing cleaves RNAs from the mammalian mitochondrial main non‐coding regulatory region, called the displacement loop. Our data demonstrate that rat cells contain a site‐specific ribonuclease mitochondrial RNA processing activity. We found that this enzyme processes the rat mitochondrial displacement‐loop RNA substrate at the level of the conserved sequence block 1, a result which is different from that for mouse. This finding correlates with the in‐vivo transcriptional analysis of the rat displacement‐loop region. Processing by homologous and heterologous ribonuclease mitochondrial RNA enzymes occurs in the same manner, suggesting a conserved mode of substrate recognition. Copyright © 1995, Wiley Blackwell. All rights reserved