title: Transcriptomic analysis of the GCN5 gene reveals mechanisms of the epigenetic regulation of virulence and morphogenesis in Ustilago maydis.
abstract: Chromatin in the eukaryotic nucleus is highly organized in the form of nucleosomes where histones wrap DNA. This structure may be altered by some chemical modifications of histones, one of them, acetylation by histone acetyltransferases (HATs) that originates relaxation of the nucleosome structure, providing access to different transcription factors and other effectors. In this way, HATs regulate cellular processes including DNA replication, and gene transcription. Previously, we isolated Ustilago maydis mutants deficient in the GCN5 HAT that are avirulent, and grow constitutively as mycelium. In this work, we proceeded to identify the genes differentially regulated by GCN5, comparing the transcriptomes of the mutant and the wild type using microarrays, to analyse the epigenetic control of virulence and morphogenesis. We identified 1203 genes, 574 positively and 629 negatively regulated in the wild type. We found that genes belonging to different categories involved in pathogenesis were downregulated in the mutant, and that genes involved in mycelial growth were negatively regulated in the wild type, offering a working hypothesis on the epigenetic control of virulence and morphogenesis of U. maydis. Interestingly, several differentially regulated genes appeared in clusters, suggesting a common regulation. Some of these belonged to pathogenesis or secondary metabolism.
authors.affiliation: Departamento de Ingeniería Genética, Unidad Irapuato, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, 36500 Irapuato, Gto., México.
authors.forename: Domingo
authors.initials: D
authors.lastname: Martínez-Soto
authors.affiliation: Biotecnología Vegetal, Centro de Biotecnologia Genómica, Instituto Politécnico Nacional, 88710 Reynosa, Tam., México.
authors.forename: Juan Manuel
authors.initials: JM
authors.lastname: González-Prieto
authors.affiliation: Departamento de Ingeniería Genética, Unidad Irapuato, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, 36500 Irapuato, Gto., México jruiz@ira.cinvestav.mx.
authors.forename: José
authors.initials: J
authors.lastname: Ruiz-Herrera
mesh_terms: D044127:Epigenesis, Genetic; D017353:Gene Deletion; D020869:Gene Expression Profiling; D015966:Gene Expression Regulation, Fungal; D051548:Histone Acetyltransferases / Q000096:biosynthesis* / Q000235:genetics; D025301:Hyphae / Q000166:cytology / Q000254:growth & development; D046228:Microarray Analysis; D014588:Ustilago / Q000166:cytology / Q000235:genetics* / Q000254:growth & development; D014774:Virulence
chemical_list: D051548:Histone Acetyltransferases
keywords: dimorphism; epigenetics; histone acetyltransferases; pathogenesis; transcriptomes