COP1
COP1 (E3 ubiquitin-protein ligase COP1, also known as RFWD2, RNF200, FAP78 and CFAP78) is a RING-type E3 ubiquitin ligase that mediates the ubiquitination and proteasomal degradation of target proteins, including the transcription factors JUN and p53. Browse Assay Genie's current range of COP1 research reagents below, or read on for the biology behind the target.
COP1 is an E3 ubiquitin ligase. E3 enzymes accept ubiquitin from an E2 ubiquitin-conjugating enzyme as a thioester and then transfer it directly to the targeted substrate, marking it for degradation by the proteasome. COP1 is involved in the ubiquitination and degradation of JUN, and it acts directly on p53 (TP53), abolishing p53-dependent transcription and apoptosis. It ubiquitinates p53 independently of MDM2 or RCHY1.
COP1 probably provides E3 activity by acting as the essential RING domain subunit of larger E3 complexes. The exception is the DCX DET1-COP1 complex, which negatively regulates JUN: here the ubiquitin ligase activity is mediated by RBX1 rather than by COP1. NCBI Gene also lists COP1 as part of the Cul4A-RING E3 ubiquitin ligase complex. Further substrates include 14-3-3 protein sigma (SFN), whose degradation leads to AKT activation and promotion of cell survival, and MTA1, which is also targeted for proteasomal degradation. When bound to TRIB1, COP1 ubiquitinates CEBPA, a substrate that lacks a canonical COP1-binding motif.
The COP1 gene belongs to the COP1 family, and the protein localises to nuclear speckles and the cytoplasm. HGNC classifies it among RING finger E3 ubiquitin protein ligases and WD repeat domain containing proteins, and it carries the previous name ring finger and WD repeat domain 2. Annotated biological processes include negative regulation of fatty acid biosynthesis, positive regulation of proteasomal ubiquitin-dependent protein catabolism and response to ionizing radiation. The mouse ortholog is Cop1.
COP1 ubiquitinates p53 independently of MDM2, abolishing p53-dependent transcription and apoptosis, which makes it a focus for studies of p53 turnover.
As a RING-type E3 ligase working within larger complexes such as DET1-COP1 and Cul4A-RING, COP1 is used to study substrate selection and proteasomal degradation.
COP1-mediated degradation of 14-3-3 sigma (SFN) leads to AKT activation and promotion of cell survival.
COP1 controls the degradation of JUN and, with TRIB1, CEBPA, offering a route into studies of transcription factor stability.
COP1 is an E3 ubiquitin ligase that mediates ubiquitination and proteasomal degradation of substrates. Reported targets include JUN, p53, 14-3-3 sigma (SFN), MTA1 and, when bound to TRIB1, CEBPA. It probably acts as the RING subunit of larger E3 complexes.
COP1 is also called RFWD2, RNF200, FAP78, CFAP78 and FLJ10416. Its previous HGNC name was ring finger and WD repeat domain 2, and its current HGNC name is COP1 E3 ubiquitin ligase. The enzyme is classified as EC 2.3.2.27.
The mouse ortholog is Cop1. COP1 directly ubiquitinates p53 and promotes its degradation, independently of MDM2 or RCHY1, and NCBI Gene links it to the response to ionizing radiation. Check the datasheet of any product for its validated reactivity.
Substrates, complex partners and other ubiquitin-pathway and COP9 signalosome targets related to COP1.
Gene and protein annotations from HGNC, NCBI Gene and UniProt Q8NHY2; product specifications from Assay Genie datasheets.