Expression of the DAL80 gene, whose product is homologous to the GATA factors and is a negative regulator of multiple nitrogen catabolic genes in Saccharomyces cerevisiae, is sensitive to nitrogen catabolite repression.
We have cloned the negative regulatory gene (DAL80) of the allantoin catabolic pathway, characterized its structure, and determined the physiological conditions that control DAL80 expression and its influence on the expression of nitrogen catabolic genes. Disruption of the DAL80 gene demonstrated that it regulates multiple nitrogen catabolic pathways. Inducer-independent expression was observed for the allantoin pathway genes DAL7 and DUR1,2, as well as the UGA1 gene required for gamma-aminobutyrate catabolism in the disruption mutant. DAL80 transcription was itself highly sensitive to nitrogen catabolite repression (NCR), and its promoter contained 12 sequences homologous to the NCR-sensitive UASNTR. The deduced DAL80 protein structure contains zinc finger and coiled-coil motifs. The DAL80 zinc finger motif possessed high homology to the transcriptional activator proteins required for expression of NCR-sensitive genes in fungi and the yeast GLN3 gene product required for functioning of the NCR-sensitive DAL UASNTR. It was also homologous to the three GATAA-binding proteins reported to be transcriptional activators in avian and mammalian tissues. The latter correlations raise the possibility that both positive and negative regulators of allantoin pathway transcription may bind to similar sequences.
Cunningham
T S
TS
Department of Microbiology and Immunology, University of Tennessee, Memphis 38163.
Cooper
T G
TG
D000481:Allantoin / Q000378:metabolism; D000595:Amino Acid Sequence; D001483:Base Sequence; D015152:Blotting, Northern; D019731:Carbon-Nitrogen Ligases; D003001:Cloning, Molecular; D004271:DNA, Fungal; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D050980:GATA Transcription Factors; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D005809:Genes, Regulator; D007700:Kinetics; D008025:Ligases / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D009584:Nitrogen / Q000378:metabolism*; D010641:Phenotype; D012097:Repressor Proteins; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D012689:Sequence Homology, Nucleic Acid; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics; D016335:Zinc Fingers
C071662:DAL80 protein, S cerevisiae; D004271:DNA, Fungal; D005656:Fungal Proteins; D050980:GATA Transcription Factors; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D000481:Allantoin; D008025:Ligases; D019731:Carbon-Nitrogen Ligases; C023270:urea carboxylase (hydrolyzing); D009584:Nitrogen