The complete and symmetric transcription of the main non coding region of rat mitochondrial genome : in vivo mapping of heavy and light transcripts

• Published in: Current genetics Vol. 17; no. 3; pp. 247 - 253
• Main Authors: SBISA, E, NARDELLI, M, TANZARELLIO, F, TULLO, A, SACCONE, C
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01-03-1990; Berlin
• Subjects: Amino Acid Sequence; Animals; Base Sequence; Biological and medical sciences; DNA, Mitochondrial - genetics; Fundamental and applied biological sciences. Psychology; Introns; Male; Molecular and cellular biology; Molecular genetics; Molecular Sequence Data; Nucleic Acid Conformation; Nucleic Acid Hybridization; Nucleotide Mapping; Rats; Rats, Inbred Strains; RNA - genetics; Transcription, Genetic; Transcription. Transcription factor. Splicing. Rna processing; Genetic mapping; Molecular processing; Rat; Nucleotide sequence; Transcription; Transcription promoter; Rodentia; Antisense RNA; D-Loop; Mitochondrial DNA; In vivo; Vertebrata; Regulation(control); Mammalia; Polyadenylation; Mitochondrial RNA
• ISSN: 0172-8083; 1432-0983
• DOI: 10.1007/BF00312616

The experiments here reported demonstrate that the main non-coding region of rat mitochondrial DNA is symmetrically transcribed. We have identified stable heavy and light transcripts, whose pattern is rather complex, in the D-loop region of rat mitochondrial DNA. Their relative concentrations have been determined. We detected heavy transcripts which encompass the whole D-loop and more abundant heavy RNA species which we interpreted as transcripts terminating downstream of the 3' end of the last coded gene (Thr-tRNA). The processed heavy RNA species contain polyA, suggesting a strict association between cleavage and polyadenylation. The pattern of light transcripts shows a long RNA, which, starting from the light strand promoter, covers the whole segment, and shorter RNA species which seems to be actively processed at the level of the conserved sequence boxes, probably acting as primers. The symmetric transcription of the D-loop containing region of rat mitochondrial DNA, and in particular the presence of stable transcripts complementary to the putative RNA primers, suggest that mechanisms mediated by interaction between complementary transcripts (antisense RNAs) might play a role in the regulation of mitochondrial DNA replication and expression.