HY3 (OS03G0309200) — Oryza sativa Japonica

Summary

Os03g0309200 (HY3/PHYB) on rice chromosome 3 encodes a phytochrome photoreceptor, a member of the phytochrome A–E family with PAS, GAF, and histidine kinase domains, and exhibits photoreceptor activity and tetrapyrrole binding. The gene is associated with detection of light, positive regulation of the phytochrome signaling pathway, and downregulation of chlorophyll anabolism. It has been linked to a wide range of agronomic traits including tiller formation, heading date, photoperiod sensitivity, sheath blight disease response, vegetative vigor, leaf area, root system morphology, plant dry weight, and far-red light sensitivity. Additional associations include responses to drought, ethylene, gibberellin, saline-alkaline stress, and reactive oxygen species, as well as regulation of plant organ formation and chromatin organization. Studies of related genes in other species link the family to shade avoidance, photoperiod sensitivity, and stress tolerance.