title: The White Collar protein WcoA of Fusarium fujikuroi is not essential for photocarotenogenesis, but is involved in the regulation of secondary metabolism and conidiation.
abstract: The fungal proteins of the White Collar photoreceptor family, represented by WC-1 from Neurospora crassa, mediate the control by light of different biochemical and developmental processes, such as carotenogenesis or sporulation. Carotenoid biosynthesis is induced by light in the gibberellin-producing fungus Fusarium fujikuroi. In an attempt to identify the photoreceptor for this response, we cloned the only WC-1-like gene present in the available Fusarium genomes, that we called wcoA. The predicted WcoA polypeptide is highly similar to WC-1 and contains the relevant functional domains of this protein. In contrast to the Neurospora counterpart, wcoA expression is not affected by light. Unexpectedly, targeted wcoA disruptant strains maintain the light-induced carotenogenesis. Furthermore, the wcoA mutants show a drastic reduction of fusarin production in the light, and produce less gibberellins and more bikaverins than the parental strain under nitrogen-limiting conditions. The changes in the production of the different products indicate a key regulatory role for WcoA in secondary metabolism of this fungus. Additionally, the mutants are severely affected in conidiation rates under different culture conditions, indicating a more general regulatory role for this protein.
authors.affiliation: Department of Genetics, Faculty of Biology, University of Seville, Av. Reina Mercedes 6, E-41012 Seville, Spain.
authors.forename: Alejandro F
authors.initials: AF
authors.lastname: Estrada
authors.forename: Javier
authors.initials: J
authors.lastname: Avalos
mesh_terms: D002338:Carotenoids / Q000096:biosynthesis* / Q000235:genetics; D003001:Cloning, Molecular; D005656:Fungal Proteins / Q000235:genetics / Q000502:physiology*; D005670:Fusarium / Q000235:genetics / Q000502:physiology*; D017353:Gene Deletion; D020869:Gene Expression Profiling; D005875:Gibberellins / Q000096:biosynthesis; D008027:Light; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D009492:Neurospora crassa / Q000235:genetics; D009584:Nitrogen / Q000378:metabolism; D020283:Photoreceptors, Microbial / Q000235:genetics / Q000502:physiology*; D010802:Phylogeny; D017434:Protein Structure, Tertiary; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013172:Spores, Fungal / Q000235:genetics / Q000254:growth & development*; D013605:T-2 Toxin / Q000096:biosynthesis; D024363:Transcription Initiation Site; D044004:Xanthones / Q000378:metabolism
chemical_list: D005656:Fungal Proteins; D005875:Gibberellins; D020283:Photoreceptors, Microbial; D044004:Xanthones; C000269:bikaverin; D002338:Carotenoids; D013605:T-2 Toxin; D009584:Nitrogen