| Primary Identifier | IPR037740 | Type | Family |
| Short Name | CSN5 |
| description | The COP9 signalosome (CSN) is a conserved protein complex that regulates the ubiquitin (Ubl) conjugation pathway by mediating the deneddylation of the cullin subunits of SCF-type E3 ligase complexes [], which leads to a decrease in Ubl ligase activity of SCF-type complexes such as SCF, CSA or DDB2 []. Protein kinases CK2 and D, which phosphorylate proteins such as cJun and p53 resulting in their degradation by the ubiquitin-26S proteasome system, also binds to CSN [, ]. The mammalian CSN typically consistis of eight subunits designated CSN1-CSN8. The fission yeast possesses a smaller version of the CSN, consisting only of six subunits, whereas a more distant CSN-like complex has been described in Saccharomyces cerevisiae [].COP9 signalosome complex subunit 5 (Rri1, CSN5 or JAB1) is a metallo-isopeptidase (MEROPS identifier M67.002) that releases the ubiquitin-like protein Nedd8 from the Cul1 subunit of SCF ubiquitin ligases []. Rri1 binds a zinc ion via the histidines in an HXH motif and an aspartic acid C-terminal to this motif []. This entry includes CSN5 homologues from yeast to human. |
