5kwn

Structural highlights

Function

COP1_ARATH 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.^{[1] [2]}

See Also

• Ubiquitin protein ligase 3D structures

References

1. ↑ Shin B, Choi G, Yi H, Yang S, Cho I, Kim J, Lee S, Paek NC, Kim JH, Song PS, Choi G. AtMYB21, a gene encoding a flower-specific transcription factor, is regulated by COP1. Plant J. 2002 Apr;30(1):23-32. PMID:11967090
2. ↑ Holm M, Ma LG, Qu LJ, Deng XW. Two interacting bZIP proteins are direct targets of COP1-mediated control of light-dependent gene expression in Arabidopsis. Genes Dev. 2002 May 15;16(10):1247-59. PMID:12023303 doi:http://dx.doi.org/10.1101/gad.969702