Figure 1.

Domain structure of Arabidopsis phyB. The photosensory domain consists of a PAS domain, a GAF domain, and a PHY domain. The output module is composed of a PAS-related domain and a HKRD. The C-terminal output module features properties for nuclear localization, dimerization and photobody formation, while the N-terminal photosensory module binds phytochromobilin via a conserved cysteine residue (Cys) and possesses the N-terminal extension (NTE) that is required for photobody formation of the full-length phyB protein. The depicted domain structure is based on (Burgie and Vierstra 2014).