The transcription of NAM7/UPF1 is enhanced in the absence of Cyp1p/Hap1p concomitant with the appearance of an ISF1-NAM7 cotranscript in Saccharomyces cerevisiae.
The two adjacent nuclear genes ISF1 and NAM7 cooperatively participate in mitochondrial functions. It is well known that Cyp1p(Hap1p) activates a number of genes involved in these same functions. We show in this paper that Cyp1p influences the transcriptional regulation of NAM7. In addition, a significant amount of ISF1-NAM7 cotranscript is observed in a cyp1 mutant context. An extensive analysis of the intergenic region which separates the two genes revealed 5' starts of the NAM7 transcripts, additional to those previously mapped. These new 5' starts overlap the 3' ends of ISF1. We propose that NAM7 is under the control of a negative Cyp1p-dependent regulator and that its absence favours a transcriptional read-through which results in the ISF1-NAM7 cotranscript we have identified.
Altamura
N
N
Centro di Studio sui Mitocondri e Metabolismo Energetico, CNR, presso Università di Bari, Italy. N.Altamura@area.ba.cnr.it
de Pinto
B
B
Castaldo
R
R
Verdiére
J
J
D000595:Amino Acid Sequence; D001483:Base Sequence; D004268:DNA-Binding Proteins; D005656:Fungal Proteins / Q000235:genetics* / Q000502:physiology; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D008969:Molecular Sequence Data; D020365:RNA Helicases; D012331:RNA, Fungal / Q000235:genetics; D012097:Repressor Proteins / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D015534:Trans-Activators / Q000235:genetics* / Q000502:physiology; D014157:Transcription Factors; D014158:Transcription, Genetic
D004268:DNA-Binding Proteins; D005656:Fungal Proteins; C058452:HAP1 protein, S cerevisiae; D012331:RNA, Fungal; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D015534:Trans-Activators; D014157:Transcription Factors; C074151:NAM7 protein, S cerevisiae; D020365:RNA Helicases