Characterization of the mtTFA gene and identification of a processed pseudogene in rat.
Mitochondrial DNA replication and transcription are regulated from essential nucleus-encoded components that interact with the mitochondrial (mt) D-loop region. Among these there is the mitochondrial transcription factor A (mtTFA or Tfam). We have determined the sequence of the cDNA mtTFA in rat and have demonstrated that the gene has a mosaic organization with six introns whose sizes we have calculated. A differential splicing transcript lacking exon 5 has been detected in all assayed tissues and represents 9.85% of the full length transcript. Beside the gene which is homologous to the one found in man and mouse, rat nuclear genome contains at least 12 copies of this gene or genome fragments with high similarity to mtTFA. We have determined the sequence of one of these copies. This resulted to have 76.26% similarity to the active gene but to lack introns, suggesting it might be a processed pseudogene. RT-PCR experiments have demonstrated that this pseudogene (psi mtTFA) is transcribed in liver tissue.
Mezzina
Maria
M
Dipartimento di Biochimica e Biologia Molecolare, Università di Bari, Via Orabona 4, 70125 Bari, Italy.
Reyes
Aurelio
A
D'Errico
Ilenia
I
Gadaleta
Gemma
G
D017398:Alternative Splicing; D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D004247:DNA / Q000235:genetics; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics*; D005091:Exons; D015870:Gene Expression; D005796:Genes / Q000235:genetics; D007438:Introns; D008297:Male; D024101:Mitochondrial Proteins; D008969:Molecular Sequence Data; D009687:Nuclear Proteins; D011544:Pseudogenes / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D014157:Transcription Factors / Q000235:genetics*; D014158:Transcription, Genetic
D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D024101:Mitochondrial Proteins; D009687:Nuclear Proteins; D012333:RNA, Messenger; C489030:Tfam protein, rat; D014157:Transcription Factors; C422562:mitochondrial transcription factor A; D004247:DNA