title: Light-dependent gene activation in Aspergillus nidulans is strictly dependent on phytochrome and involves the interplay of phytochrome and white collar-regulated histone H3 acetylation.
abstract: The ability for light sensing is found from bacteria to humans but relies only on a small number of evolutionarily conserved photoreceptors. A large number of fungi react to light, mostly to blue light. Aspergillus nidulans also responds to red light using a phytochrome light sensor, FphA, for the control of hundreds of light-regulated genes. Here, we show that photoinduction of one light-induced gene, ccgA, occurs mainly through red light. Induction strictly depends on phytochrome and its histidine-kinase activity. Full light activation also depends on the Velvet protein, VeA. This putative transcription factor binds to the ccgA promoter in an fphA-dependent manner but independent of light. In addition, the blue light receptor LreA binds to the ccgA promoter in the dark but is released after blue or red light illumination and together with FphA modulates gene expression through histone H3 modification. LreA interacts with the acetyltransferase GcnE and with the histone deacetylase HdaA. ccgA induction is correlated to an increase of the acetylation level of lysine 9 in histone H3. Our results suggest regulation of red light-induced genes at the transcriptional level involving transcription factor(s) and epigenetic control through modulation of the acetylation level of histone H3.
authors.affiliation: Department of Microbiology, Karlsruhe Institute of Technology, Institute for Applied Biosciences, Hertzstrasse 16, D-76187, Karlsruhe, Germany.
authors.forename: Maren
authors.initials: M
authors.lastname: Hedtke
authors.affiliation: Department of Microbiology, Karlsruhe Institute of Technology, Institute for Applied Biosciences, Hertzstrasse 16, D-76187, Karlsruhe, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Rauscher
authors.affiliation: Department of Microbiology, Karlsruhe Institute of Technology, Institute for Applied Biosciences, Hertzstrasse 16, D-76187, Karlsruhe, Germany.
authors.forename: Julian
authors.initials: J
authors.lastname: Röhrig
authors.affiliation: Centre for Plant Biotechnology and Genomics (CBGP) U.P.M. - I.N.I.A., Campus de Montegancedo, Autopista M-40 (Km 38), 28223, Pozuelo de Alarcón, Madrid, Spain.
authors.forename: Julio
authors.initials: J
authors.lastname: Rodríguez-Romero
authors.affiliation: Department of Microbiology, Karlsruhe Institute of Technology, Institute for Applied Biosciences, Hertzstrasse 16, D-76187, Karlsruhe, Germany.
authors.forename: Zhenzhong
authors.initials: Z
authors.lastname: Yu
authors.affiliation: Department of Microbiology, Karlsruhe Institute of Technology, Institute for Applied Biosciences, Hertzstrasse 16, D-76187, Karlsruhe, Germany.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Fischer
mesh_terms: D000107:Acetylation; D001233:Aspergillus nidulans / Q000235:genetics* / Q000378:metabolism / Q000528:radiation effects*; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal / Q000528:radiation effects*; D006657:Histones / Q000235:genetics / Q000378:metabolism*; D008027:Light; D020283:Photoreceptors, Microbial / Q000235:genetics / Q000378:metabolism; D010834:Phytochrome / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D005656:Fungal Proteins; D006657:Histones; D020283:Photoreceptors, Microbial; D014157:Transcription Factors; D010834:Phytochrome