A MADS-box homologue in Ustilago maydis regulates the expression of pheromone-inducible genes but is nonessential.
Mating and pathogenic development in the smut fungus Ustilago maydis are controlled by a pheromone/receptor system and two homeodomain proteins, bEp and bWp, which form heterodimers in nonallelic combinations. We describe the isolation of a gene, umc1, encoding a MADS-box protein, which displays significant similarity to the Saccharomyces cerevisiae MCM1 gene. umc1 complemented the viability defect of yeast mcm1 mutants. In U. maydis, umc1 deletion mutants were viable and pathogenic development was unaffected. Nevertheless, the basal expression levels of several pheromone-inducible genes were significantly reduced leading to an attenuated mating reaction. In contrast to S. cerevisiae, where Mcm1p plays a crucial role in the cell-type specific expression of a- and alpha-specific genes, the U. maydis umc1 gene appears to have only a modulatory effect on the expression of mating type-specific genes.
Krüger
J
J
Institut für Genetik und Mikrobiologie der Universität München, Germany.
Aichinger
C
C
Kahmann
R
R
Bölker
M
M
D000595:Amino Acid Sequence; D001483:Base Sequence; D001665:Binding Sites; D003001:Cloning, Molecular; D016384:Consensus Sequence; D004271:DNA, Fungal; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics; D005656:Fungal Proteins / Q000235:genetics / Q000502:physiology*; D017353:Gene Deletion; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D049770:Genes, Mating Type, Fungal; D026341:Minichromosome Maintenance 1 Protein; D008969:Molecular Sequence Data; D010641:Phenotype; D010675:Pheromones / Q000502:physiology; D011498:Protein Precursors / Q000235:genetics; D051964:Receptors, Mating Factor; D018000:Receptors, Peptide / Q000502:physiology; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics; D014588:Ustilago / Q000187:drug effects / Q000235:genetics*
D004271:DNA, Fungal; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D026341:Minichromosome Maintenance 1 Protein; D010675:Pheromones; D011498:Protein Precursors; D051964:Receptors, Mating Factor; D018000:Receptors, Peptide; D014157:Transcription Factors; C110282:UMC1 protein, Ustilago maydis