title: Beyond asexual development: modifications in the gene expression profile caused by the absence of the Aspergillus nidulans transcription factor FlbB.
abstract: In the model fungus Aspergillus nidulans, asexual development is induced from vegetative hyphae by a set of early regulators including the bZIP-type transcription factor FlbB. To determine the range of genes under the influence of the transcriptional activity of FlbB and to characterize their role in fungal development, we sequenced and compared the transcriptomes of a ΔflbB mutant and its isogenic wild-type strain at different developmental stages. Results confirmed the activating role of FlbB on downstream regulators of conidiation such as flbD and brlA. However, FlbB has additional functions beyond the induction of asexual development. Among the changes observed, absence of a functional FlbB caused induction of the dba cluster and synthesis of a secondary metabolite with bactericidal properties. In addition, a new transcriptional target of FlbB was unveiled, urdA, that codes for a putative transcription factor that represses premature sexual development. Taken together, our results indicate that the activators of asexual development simultaneously exert a role on other cellular functions, including an inhibitory effect on the sexual cycle, and reinforce the hypothesis that mutually exclusive metabolic and cellular patterns are associated with different morphogenetic programs.
authors.affiliation: Department of Applied Chemistry, Faculty of Chemistry, University of The Basque Country, Manuel de Lardizabal, 3, 20018, San Sebastian, Spain.
authors.forename: Elixabet
authors.initials: E
authors.lastname: Oiartzabal-Arano
authors.affiliation: Department of Applied Chemistry, Faculty of Chemistry, University of The Basque Country, Manuel de Lardizabal, 3, 20018, San Sebastian, Spain.
authors.forename: Aitor
authors.initials: A
authors.lastname: Garzia
authors.affiliation: Biodonostia Research Institute, Genomic Platform, Doctor Begiristain, s/n, 20014, San Sebastian, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Gorostidi
authors.affiliation: Department of Applied Chemistry, Faculty of Chemistry, University of The Basque Country, Manuel de Lardizabal, 3, 20018, San Sebastian, Spain.
authors.forename: Unai
authors.initials: U
authors.lastname: Ugalde
authors.affiliation: Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas (CSIC), Ramiro de Maeztu, 9, 28040, Madrid,Spain.
authors.forename: Eduardo A
authors.initials: EA
authors.lastname: Espeso
authors.affiliation: Department of Applied Chemistry, Faculty of Chemistry, University of The Basque Country, Manuel de Lardizabal, 3, 20018, San Sebastian, Spain oier.echeveste@ehu.es.
authors.forename: Oier
authors.initials: O
authors.lastname: Etxebeste
mesh_terms: D001233:Aspergillus nidulans / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism / Q000502:physiology; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D017353:Gene Deletion; D018507:Gene Expression Regulation, Developmental; D015966:Gene Expression Regulation, Fungal; D012100:Reproduction, Asexual / Q000235:genetics*; D064210:Secondary Metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D059467:Transcriptome
chemical_list: D005656:Fungal Proteins; D014157:Transcription Factors
keywords: Aspergillus nidulans; development; mRNA sequencing; secondary metabolite cluster; transcriptional regulation