The COP9 signalosome is an essential regulator of development in the filamentous fungus Aspergillus nidulans.
The COP9 signalosome (CSN) is a conserved multiprotein complex involved in regulation of eukaryotic development. The deduced amino acid sequences of two Aspergillus nidulans genes, csnD and csnE, show high identities to the fourth and fifth CSN subunits of higher eukaryotes. The csnD transcript is abundant during vegetative growth as well as development and the corresponding protein accumulates in the nucleus. Strains deleted for either csn gene are viable and show identical mutant phenotypes at conditions that allow development: hyphae appear partly red and contain cells of reduced size. Additionally, light dependence of propagation onset is affected. The Delta csn mutants are capable of initiating the sexual cycle and develop primordia, but maturation to sexual fruit bodies is blocked. This developmental arrest could not be overcome by overexpression of the sexual activator velvet (VEA). We conclude that the COP9 signalosome in A. nidulans is a key regulator of sexual development, and its proposed structural and functional conservation to the CSN of higher eukaryotes enables studies on this regulatory complex in a genetically amenable organism.
Busch
Silke
S
Institut für Mikrobiologie und Genetik, Georg-August-Universität, Grisebachstrasse 8, D-37077 Göttingen, Germany.
Eckert
Sabine E
SE
Krappmann
Sven
S
Braus
Gerhard H
GH
D000595:Amino Acid Sequence; D001233:Aspergillus nidulans / Q000235:genetics / Q000254:growth & development* / Q000528:radiation effects / Q000648:ultrastructure; D018076:DNA, Complementary / Q000235:genetics; D004268:DNA-Binding Proteins / Q000737:chemistry; D005656:Fungal Proteins / Q000235:genetics / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental / Q000528:radiation effects; D015966:Gene Expression Regulation, Fungal / Q000528:radiation effects; D005800:Genes, Fungal; D008027:Light; D008969:Molecular Sequence Data; D009024:Morphogenesis; D009097:Multienzyme Complexes / Q000235:genetics / Q000502:physiology*; D016296:Mutagenesis; D010447:Peptide Hydrolases; D010641:Phenotype; D010860:Pigments, Biological / Q000378:metabolism; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000502:physiology; D012098:Reproduction; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D014157:Transcription Factors / Q000737:chemistry; D014158:Transcription, Genetic
D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D009097:Multienzyme Complexes; D010860:Pigments, Biological; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; D010447:Peptide Hydrolases