5′ Flanking sequences of human MRP/7-2 RNA gene are required and sufficient for the transcription by RNA polymerase III

Abstract

Human mitochondrial RNA processing (MRP) RNA is a 270 nucleotide-long small RNA found as ribonucleoprotein particles. In this study, we isolated four human genomic clones with homology to human MRP RNA. Two of these clones contained one copy each of the real gene coding for human MRP RNA; the other two clones represented a processed pseudogene. The Southern blot with the genomic DNA showed that the haploid human genome contains one copy of real gene and a few pseudogenes for MRP/7-2 RNA. The human MRP RNA is synthesized by RNA polymerase III and the 5′ flanking sequences −84 to 1 of MRP RNA gene, containing TATA and PSE-like elements, are required and sufficient for transcription in vitro.