Detection of novel transcripts in the human mitochondrial DNA region coding for ATPase8—ATPase6 subunits

Abstract

We have analyzed the tRNA Lys , ATPase8, ATPase6, COIII region of mitochondrial DNA in several human tissues. Beside the mature tRNA Lys , ATPase8 and ATPase6 common mRNA, and COIII mRNA, we have characterized two new transcripts, called RNA 20 and RNA 21. The RNA 20 is a precursor species which contains the tRNA Lys plus the ATPase8 and ATPase6 common mRNA; the RNA 21 is an RNA species shorter than the ATPase8 and ATPase6 common mRNA. The relative concentration of the mature with respect to that of the new species proved different in the various tissues. These findings provide new insights into the mitochondrial transcription mechanism opening the question of a possibly regulatory role of the processing on the expression of the mitochondrial genome.