UBA domain found in Arabidopsis thaliana E3 ubiquitin-protein ligase UPL1 (atUPL1), UPL2 (atUPL2) and similar proteins
The family includes two highly similar 405-kDa HECT E3 ubiquitin-protein ligases (UPLs), UPL1 and UPL2, from Arabidopsis thaliana. The HECT E3 UPL family plays a prominent role in the ubiquitination of plant proteins. The biological functions of UPL1 and UPL2 remain unclear. Both of them contain a ubiquitin-associated (UBA) domain and a C-terminal HECT domain. UBA domain may be involved in ubiquitin metabolism. HECT domain is necessary and sufficient for their E3 catalytic activity, but requires ATP, E1 and an E2 of the Arabidopsis UBC8 family to ubiquitinate proteins.
Jiyao W et al.(2023). "The conserved domain database in 2023.",