The molecular basis of COP1 action during photomorphogenesis

J Exp Bot. 2024 Apr 29:erae181. doi: 10.1093/jxb/erae181. Online ahead of print.

Abstract

COP1 (CONSTITUTIVE PHOTOMORPHOGENIC1), a repressor of seedling photomorphogenesis, is tightly controlled by light. In Arabidopsis, COP1 primarily acts as a part of large E3 ligase complexes and targets key light-signaling factors for ubiquitination and degradation. Upon light perception, the action of COP1 is precisely modulated by active photoreceptors. During seedling development, light plays a predominant role in modulating seedling morphogenesis, including inhibition of hypocotyl elongation, cotyledon opening and expansion, and chloroplast development. These visible morphological changes evidently are resulted from networks of molecular action. In this review, we summarize the current knowledge about the molecular role of COP1 in mediating light-controlled seedling development.

Keywords: COP1; E3 ubiquitin ligase; light; molecular basis; photomorphogenesis; ubiquitination.