COP1

Constitutively Photomorphogenic 1 (COP1), also known as RFWD2, is an E3 ubiquitin ligase mediating protein ubiquitination and proteasomal degradation. Initially characterized in plant photomorphogenesis, mammalian COP1 regulates cell proliferation, apoptosis, and DNA repair by targeting substrates like p53, c-Jun, and p27 for degradation.
Dysregulated COP1 is linked to breast, lung, and colorectal cancers, acting as an oncogene via suppressing tumor suppressors. It interacts with pathways including p53, NF-κB, and MAPK. Preclinical studies explore small-molecule inhibitors of COP1’s ligase activity, which stabilize p53 and inhibit tumor growth, showing potential as anticancer therapeutics.