title: Two components of a velvet-like complex control hyphal morphogenesis, conidiophore development, and penicillin biosynthesis in Penicillium chrysogenum.
abstract: Penicillium chrysogenum is the industrial producer of the antibiotic penicillin, whose biosynthetic regulation is barely understood. Here, we provide a functional analysis of two major homologues of the velvet complex in P. chrysogenum, which we have named P. chrysogenum velA (PcvelA) and PclaeA. Data from array analysis using a DeltaPcvelA deletion strain indicate a significant role of PcVelA on the expression of biosynthesis and developmental genes, including PclaeA. Northern hybridization and high-performance liquid chromatography quantifications of penicillin titers clearly show that both PcVelA and PcLaeA play a major role in penicillin biosynthesis in a producer strain that underwent several rounds of UV mutagenesis during a strain improvement program. Both regulators are further involved in different developmental processes. While PcvelA deletion leads to light-independent conidial formation, dichotomous branching of hyphae, and pellet formation in shaking cultures, a DeltaPclaeA strain shows a severe impairment in conidiophore formation under both light and dark conditions. Bimolecular fluorescence complementation assays provide evidence for a velvet-like complex in P. chrysogenum, with structurally conserved components that have distinct developmental roles, illustrating the functional plasticity of these regulators in genera other than Aspergillus.
authors.affiliation: Christian Doppler Laboratory for Fungal Biotechnology, Lehrstuhl für Allgemeine und Molekulare Botanik, Ruhr-Universität Bochum, Universitätsstrasse 150, 44780 Bochum, Germany.
authors.forename: Birgit
authors.initials: B
authors.lastname: Hoff
authors.forename: Jens
authors.initials: J
authors.lastname: Kamerewerd
authors.forename: Claudia
authors.initials: C
authors.lastname: Sigl
authors.forename: Rudolf
authors.initials: R
authors.lastname: Mitterbauer
authors.forename: Ivo
authors.initials: I
authors.lastname: Zadra
authors.forename: Hubert
authors.initials: H
authors.lastname: Kürnsteiner
authors.forename: Ulrich
authors.initials: U
authors.lastname: Kück
mesh_terms: D005453:Fluorescence; D005656:Fungal Proteins / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D055786:Gene Knockout Techniques; D005800:Genes, Fungal / Q000235:genetics; D005816:Genetic Complementation Test; D025301:Hyphae / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism / Q000648:ultrastructure; D009024:Morphogenesis; D020411:Oligonucleotide Array Sequence Analysis; D010406:Penicillins / Q000096:biosynthesis*; D010408:Penicillium chrysogenum / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism* / Q000648:ultrastructure; D011485:Protein Binding; D012100:Reproduction, Asexual; D017386:Sequence Homology, Amino Acid; D013172:Spores, Fungal / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D005656:Fungal Proteins; D010406:Penicillins