Of P and Z: Mitochondrial tRNA processing enzymes

► A great diversity of RNase P enzymes is found in mitochondria of different organisms. ► The RNase P of many fungi contains a highly degenerated RNA. ► Most mitochondrial RNase P enzymes, however, are composed of protein only. ► Mitochondrial 3′-end processing seems to rely exclusively on the long, eukaryal form of RNase Z.