Direct Targeting of Light Signals to a Promoter Element-Bound Transcription Factor

作者：Jaime F. Martínez‐García, Enamul Huq, Peter H. Quail · 发表于：Science · 年份：2000 · DOI：10.1126/science.288.5467.859 · 被引用次数：701 · 研究领域：Light effects on plants、Plant Molecular Biology Research、Photosynthetic Processes and Mechanisms

Light signals perceived by the phytochrome family of sensory photoreceptors are transduced to photoresponsive genes by an unknown mechanism. Here, we show that the basic helix-loop-helix transcription factor PIF3 binds specifically to a G-box DNA-sequence motif present in various light-regulated gene promoters, and that phytochrome B binds reversibly to G-box-bound PIF3 specifically upon light-triggered conversion of the photoreceptor to its biologically active conformer. We suggest that the phytochromes may function as integral light-switchable components of transcriptional regulator complexes, permitting continuous and immediate sensing of changes in this environmental signal directly at target gene promoters.