nmt2 of fission yeast: a second thiamine-repressible gene co-ordinately regulated with nmt1.
We previously described a screen for thiamine-repressible genes in Schizosaccharomyces pombe and reported on one such gene, nmt1, required for thiamine biosynthesis. Here we describe a second gene, nmt2, recovered in the same screen. Disruption of nmt2 also resulted in thiamine auxotrophy, indicating a role for the nmt2 gene product in thiamine biosynthesis. Both genes are highly transcribed in minimal medium and repressed in medium containing thiamine, and nuclear 'run-on' experiments confirm that expression in both cases is controlled by the rate of transcription initiation. The virtually identical kinetics of induction and repression suggest that the two genes are co-ordinately regulated. Sequence comparison of the two promoters reveals a canonical TATA box, downstream of which is a perfectly conserved 11 bp element. Transcript mapping experiments show that transcription initiation of both genes is centred on this element.
Manetti
A G
AG
Department of Evolutionary Biology, University of Siena, Italy.
Rosetto
M
M
Maundrell
K G
KG
D000595:Amino Acid Sequence; D001483:Base Sequence; D005656:Fungal Proteins / Q000235:genetics*; D015966:Gene Expression Regulation, Fungal / Q000187:drug effects*; D005800:Genes, Fungal / Q000235:genetics*; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000235:genetics; D015183:Restriction Mapping; D012568:Schizosaccharomyces / Q000187:drug effects / Q000235:genetics*; D029702:Schizosaccharomyces pombe Proteins; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D013831:Thiamine / Q000494:pharmacology*; D014158:Transcription, Genetic
D005656:Fungal Proteins; D029702:Schizosaccharomyces pombe Proteins; C090868:THI2 protein, S pombe; D013831:Thiamine