E3 ubiquitin-protein ligase COP1

UniProtKB accession:  P43254

Grouped By:  Matching UniProtKB accession

UniProtKB description:  E3 ubiquitin-protein ligase that acts as a repressor of photomorphogenesis and as an activator of etiolation in darkness. E3 ubiquitin ligases accept ubiquitin from an E2 ubiquitin-conjugating enzyme in the form of a thioester and then directly transfers the ubiquitin to targeted substrates. Represses photomorphogenesis in darkness by mediating ubiquitination and subsequent proteasomal degradation of light-induced transcription factors such as HY5, HYH and LAF1. Down-regulates MYB21, probably via ubiquitination process. Light stimuli abrogate the repression of photomorphogenesis, possibly due to its localization to the cytoplasm. Could play a role in switching between skotomorphogenetic and photomorphogenetic pathways. Mediates the ubiquitination-dependent degradation of HY5 in the darkness during seedling development (e.g. hypocotyl growth) (PubMed:26474641). Represses CIP7 in darkness (PubMed:9668129). Triggers ubiquitination and subsequent protein degradation of UNE10/PIF8, PCH1 and PCHL in the dark (PubMed:31732705).