title: Expression of asexual developmental regulator gene abaA is affected in the double mutants of classes I and II chitin synthase genes, chsC and chsA, of Aspergillus nidulans.
abstract: The chsA and chsC encode classes II and I chitin synthases, respectively, of the filamentous fungus Aspergillus nidulans. The DeltachsA DeltachsC double mutants (DeltaAC mutants) show defects in asexual development: a striking reduction in the number of conidiophores and aberrant conidiophore morphology. Here, we examined the involvement of regulatory genes for asexual development (brlA, abaA, and medA) in the conidiation defects of the DeltaAC mutants. Spatial expression patterns of brlA, abaA, and medA in conidiophores of the wild-type strains and DeltaAC mutants were examined by in-situ staining using a reporter gene; expression of either gene was detected at abnormal sterigmata in the DeltaAC mutants as well as at normal ones in the wild-type strain. However, abaA expression was not prominent at a subset of conidiophores developing long chains of aberrant sterigmata, suggesting that induction of the abaA expression was retarded in the DeltaAC mutants. Based on these results and those previously presented, possible mechanisms involved in the conidiation defects are discussed.
authors.affiliation: Department of Biotechnology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, 113-8657 Tokyo, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Ichinomiya
authors.forename: Akinori
authors.initials: A
authors.lastname: Ohta
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Horiuchi
mesh_terms: D001233:Aspergillus nidulans / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D015152:Blotting, Northern; D002687:Chitin Synthase / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins / Q000235:genetics*; D005656:Fungal Proteins / Q000235:genetics*; D015971:Gene Expression Regulation, Enzymologic; D015966:Gene Expression Regulation, Fungal; D005809:Genes, Regulator; D009154:Mutation; D009994:Osmolar Concentration; D016133:Polymerase Chain Reaction; D013172:Spores, Fungal / Q000235:genetics / Q000254:growth & development; D014157:Transcription Factors / Q000235:genetics*; D001616:beta-Galactosidase / Q000378:metabolism
chemical_list: C419553:AbaA protein, Aspergillus nidulans; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D014157:Transcription Factors; D002687:Chitin Synthase; D001616:beta-Galactosidase