active phytochrome binding domain
Protein DomainThe active phytochrome binding (APB) domain is a protein interaction module present in most phytochrome-interacting factors (PIFs) that mediates binding to light-activated phytochrome B (phyB). In Arabidopsis PIF4 and PIF5, this domain is required for phyB-associated, phosphorylation-preceded, proteasome-sensitive degradation in a light-regulated shade-avoidance pathway.