PIF4 — Brachypodium distachyon

Summary

Brachypodium distachyon gene BRADI_1G58230V3 (BdPIF4) encodes a basic helix-loop-helix (bHLH) transcription factor with phytochrome-binding, photoreceptor, and transcription coactivator activities. It is associated with the positive and negative regulation of phytochrome signaling, thermomorphogenesis, auxin biosynthesis, anthocyanin metabolism, and responses to red and far-red light, water-immersion stress, and superoxide. The gene has been linked to traits including leaf rolling, leaf width, shoot elongation under submergence, flower diameter, fruit set, seedling cotyledon size, vegetative vigor, photoperiod sensitivity, brassinosteroid content, total soluble sugar content, panicle number, seed set, and peduncle length. It is also connected to phenotypes such as height, biomass, yield, stress tolerance, drought response, and disease susceptibility. Studies of related genes in other species link the family to shade avoidance, thermosensing, and circadian regulation.