Present address: Department of Biosciences, University of Kent at Canterbury, Canterbury, Kent CT2 7NJ, UK.
The COP9 signalosome is an essential regulator of development in the filamentous fungus Aspergillus nidulans
Article first published online: 28 JAN 2004
Volume 49, Issue 3, pages 717–730, August 2003
How to Cite
Busch, S., Eckert, S. E., Krappmann, S. and Braus, G. H. (2003), The COP9 signalosome is an essential regulator of development in the filamentous fungus Aspergillus nidulans. Molecular Microbiology, 49: 717–730. doi: 10.1046/j.1365-2958.2003.03612.x
- Issue published online: 28 JAN 2004
- Article first published online: 28 JAN 2004
- Accepted 6 May, 2003.
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 Δcsn 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.