COP9 — Arabidopsis thaliana

Summary

AT4G14110 (COP9) encodes the COP9 signalosome complex subunit 8 (CSN8), a PCI-domain protein with metalloendopeptidase, ubiquitin-protein transferase, and DNA-binding transcription factor activities, and is associated with protein binding and translation initiation factor activity. In Arabidopsis, COP9 is linked to photomorphogenic development, hypocotyl elongation, G2 phase progression, and cell cycle control, as well as protein deneddylation and regulation of protein stability. It localizes to the COP9 signalosome, cullin-RING ligase complex, nucleus, and cytosol. The gene is associated with numerous traits including yield, flowering time, seed development, inflorescence height, floral organ number and identity, embryo development, anthocyanin content, auxin content and sensitivity, UV light sensitivity, osmotic response, and high temperature stress response. Studies of related genes in other species link the family to spikelet number.