The COP9 signalosome.
The COP9 signalosome (CSN) is composed of eight distinct subunits and is highly homologous to the lid sub-complex of the 26S proteasome. CSN was initially defined as a repressor of photomorphogenesis in Arabidopsis, and it has now been found to participate in diverse cellular and developmental processes in various eukaryotic organisms. Recently, CSN was revealed to have a metalloprotease activity centered in the CSN5/Jab1 subunit, which removes the post-translational modification of a ubiquitin-like protein, Nedd8/Rub1, from the cullin component of SCF ubiquitin E3 ligase (i.e., de-neddylation). In addition, CSN is associated with de-ubiquitination activity and protein kinase activities capable of phosphorylating important signaling regulators. The involvement of CSN in a number of cellular and developmental processes has been attributed to its control over ubiquitin-proteasome-mediated protein degradation.
Wei
Ning
N
Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, Connecticut 06520-8104, USA. ning.wei@yale.edu
Deng
Xing Wang
XW
D000818:Animals; D029681:Arabidopsis Proteins; D000075686:COP9 Signalosome Complex; D006801:Humans; D008666:Metalloendopeptidases / Q000378:metabolism; D046912:Multiprotein Complexes; D000075687:NEDD8 Protein; D010447:Peptide Hydrolases; D010766:Phosphorylation; D021122:Protein Subunits / Q000378:metabolism*; D021381:Protein Transport / Q000502:physiology; D011506:Proteins / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*; D043743:Ubiquitin-Protein Ligase Complexes / Q000378:metabolism*; D014452:Ubiquitins / Q000378:metabolism*
D029681:Arabidopsis Proteins; D046912:Multiprotein Complexes; D000075687:NEDD8 Protein; C082860:NEDD8 protein, human; D021122:Protein Subunits; D011506:Proteins; C513170:RUB1 protein, Arabidopsis; D029701:Saccharomyces cerevisiae Proteins; D014452:Ubiquitins; D043743:Ubiquitin-Protein Ligase Complexes; D010447:Peptide Hydrolases; D000075686:COP9 Signalosome Complex; D008666:Metalloendopeptidases; C468276:Rri1 protein, S cerevisiae