title: An eight-subunit COP9 signalosome with an intact JAMM motif is required for fungal fruit body formation.
abstract: Fruit body formation in filamentous fungi is a complex and yet hardly understood process. We show here that protein turnover control is crucial for Aspergillus nidulans development. Deletion of genes encoding COP9 signalosome (CSN) subunits 1, 2, 4, or 5 resulted in identical blocks in fruit body formation. The CSN multiprotein complex controls ubiquitin-dependent protein degradation in eukaryotes. Six CSN subunits interacted in a yeast two-hybrid analysis, and the complete eight-subunit CSN was recruited by a functional tandem affinity purification tag fusion of subunit 5 (CsnE). The tagged CsnE was unable to recruit any CSN subunit in a strain deleted for subunit 1 or subunit 4. Mutations in the JAMM metalloprotease core of CsnE resulted in mutant phenotypes identical to those of csn deletion strains. We propose that a correctly assembled CSN including a functional JAMM links protein turnover to fungal sexual development.
authors.affiliation: Institut für Mikrobiologie und Genetik, Georg-August-Universität, Grisebachstrasse 8, D-37077 Göttingen, Germany.
authors.forename: Silke
authors.initials: S
authors.lastname: Busch
authors.forename: Elke U
authors.initials: EU
authors.lastname: Schwier
authors.forename: Krystyna
authors.initials: K
authors.lastname: Nahlik
authors.forename: Ozür
authors.initials: O
authors.lastname: Bayram
authors.forename: Kerstin
authors.initials: K
authors.lastname: Helmstaedt
authors.forename: Oliver W
authors.initials: OW
authors.lastname: Draht
authors.forename: Sven
authors.initials: S
authors.lastname: Krappmann
authors.forename: Oliver
authors.initials: O
authors.lastname: Valerius
authors.forename: William N
authors.initials: WN
authors.lastname: Lipscomb
authors.forename: Gerhard H
authors.initials: GH
authors.lastname: Braus
mesh_terms: D020816:Amino Acid Motifs; D001233:Aspergillus nidulans / Q000235:genetics / Q000254:growth & development*; D000075686:COP9 Signalosome Complex; D016681:Genome, Fungal; D046912:Multiprotein Complexes / Q000737:chemistry* / Q000502:physiology; D010447:Peptide Hydrolases / Q000737:chemistry* / Q000502:physiology; D010641:Phenotype; D021122:Protein Subunits
chemical_list: D046912:Multiprotein Complexes; D021122:Protein Subunits; D010447:Peptide Hydrolases; D000075686:COP9 Signalosome Complex