PIF4 — Brachypodium distachyon

Summary

BdPIF4 (BRADI_1G06670V3) on Brachypodium distachyon chromosome 1 encodes a basic helix-loop-helix (bHLH) transcription factor of the PIF3-like family, with annotated transcription regulator activator activity, phytochrome binding, and red/far-red light photoreceptor activity. The gene is associated with positive and negative regulation of the phytochrome signaling pathway, positive regulation of thermomorphogenesis, regulation of auxin biosynthetic process, and regulation of photosynthesis light reaction. It is linked to numerous traits including leaf area, vegetative vigor, relative shoot elongation under submergence, photoperiod sensitivity, panicle number, seed set percent, and brassinosteroid content. Localization evidence connects the product to chromatin, nuclear speck, chloroplast nucleoid, and plastid-encoded RNA polymerase complex. Studies of related genes in other species link the PIF4 family to shade avoidance, circadian regulation, auxin signaling, and drought stress response.