title: The UmGcn5 gene encoding histone acetyltransferase from Ustilago maydis is involved in dimorphism and virulence.
abstract: We isolated a gene encoding a histone acetyltransferase from Ustilago maydis (DC.) Cda., which is orthologous to the Saccharomyces cerevisiae GCN5 gene. The gene was isolated from genomic clones identified by their specific hybridization to a gene fragment obtained by the polymerase chain reaction (PCR). This gene (Umgcn5; um05168) contains an open reading frame (ORF) of 1421bp that encodes a putative protein of 473 amino acids with a Mr. of 52.6kDa. The protein exhibits a high degree of homology with histone acetyltransferases from different organisms. Null a2b2 ΔUmgcn5 mutants were constructed by substitution of the region encoding the catalytic site with a hygromycin B resistance cassette. Null a1b1 ΔUmgcn5 mutants were isolated from genetic crosses of a2b2 ΔUmgcn5 and a1b1 wild-type strains in maize. Mutants displayed a slight reduction in growth rate under different conditions, and were more sensitive than the wild type to stress conditions, but more important, they grew as long mycelial cells, and formed fuzz-like colonies under all conditions where wild-type strains grew in the yeast-like morphology and formed smooth colonies. This phenotype was not reverted by cAMP addition. Mutants were not virulent to maize plants, and were unable to form teliospores. These phenotypic alterations of the mutants were reverted by their transformation with the wild-type gene.
authors.affiliation: Biotecnología Vegetal, Centro de Biotecnología Genómica, Instituto Politécnico Nacional, Reynosa, Tam. 88710, Mexico; Departamento de Ingeniería Genética, Centro de Investigación y de Estudios Avanzados del I.P.N, Unidad Irapuato, Irapuato, Gto. 36500, Mexico.
authors.forename: Juan Manuel
authors.initials: JM
authors.lastname: González-Prieto
authors.affiliation: Biotecnología Vegetal, Centro de Biotecnología Genómica, Instituto Politécnico Nacional, Reynosa, Tam. 88710, Mexico; Departamento de Ingeniería Genética, Centro de Investigación y de Estudios Avanzados del I.P.N, Unidad Irapuato, Irapuato, Gto. 36500, Mexico.
authors.forename: Raymundo
authors.initials: R
authors.lastname: Rosas-Quijano
authors.affiliation: Departamento de Microbiología y Genética, CIETUS, IBSAL, Universidad de Salamanca, 37007 Salamanca, Spain.
authors.forename: Angel
authors.initials: A
authors.lastname: Domínguez
authors.affiliation: Departamento de Ingeniería Genética, Centro de Investigación y de Estudios Avanzados del I.P.N, Unidad Irapuato, Irapuato, Gto. 36500, Mexico. Electronic address: jruiz@ira.cinvestav.mx.
authors.forename: José
authors.initials: J
authors.lastname: Ruiz-Herrera
mesh_terms: D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D017353:Gene Deletion; D051548:Histone Acetyltransferases / Q000235:genetics* / Q000378:metabolism; D009154:Mutation; D017421:Sequence Analysis; D013312:Stress, Physiological; D014588:Ustilago / Q000472:pathogenicity* / Q000502:physiology*; D014774:Virulence; D003313:Zea mays / Q000382:microbiology
chemical_list: D005656:Fungal Proteins; D051548:Histone Acetyltransferases
keywords: Corn smut; Histone acetylation; Umgcn5; Ustilago maydis; Virulence factors