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The pheromone response factor coordinates filamentous growth and pathogenicity in Ustilago maydis.

ABSTRACT: In Ustilago maydis, the a and b mating type loci regulate cell fusion, filamentous growth and pathogenicity. The a locus encodes a pheromone-based cell recognition system, and the b locus specifies two homeodomain proteins. The expression of all genes in the a and b loci is induced by pheromone. We have identified a HMG protein (Prf1) that binds sequence specifically to pheromone response elements present in the a and b loci. prf1 mutants do not express the a and b genes and are sterile. The disruption of prf1 in pathogenic haploid strains results in a loss of pathogenicity. The constitutive expression of the b genes restores pathogenicity and induces filamentous growth in the absence of the pheromone signal. These results provide evidence that pheromone signalling, filamentous growth and pathogenic development are linked through Prf1.

SUBMITTER: Hartmann HA

PROVIDER: S-EPMC450074 | biostudies-other | 1996 Apr

REPOSITORIES: biostudies-other

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The pheromone response factor coordinates filamentous growth and pathogenicity in Ustilago maydis.

Hartmann H A HA Kahmann R R Bölker M M

The EMBO journal 19960401 7

In Ustilago maydis, the a and b mating type loci regulate cell fusion, filamentous growth and pathogenicity. The a locus encodes a pheromone-based cell recognition system, and the b locus specifies two homeodomain proteins. The expression of all genes in the a and b loci is induced by pheromone. We have identified a HMG protein (Prf1) that binds sequence specifically to pheromone response elements present in the a and b loci. prf1 mutants do not express the a and b genes and are sterile. The dis ...[more]

PMID: 8612587

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