Study : Cryptochromes interact directly with PIFs to control plant growth in limiting blue light
Cryptochromes interact directly with PIFs to control plant growth in limiting blue light
Sun-loving plants have the ability to detect and avoid shading through sensing of both blue and red light wavelengths. Higher plant cryptochromes (CRYs) control how plants modulate growth in response to changes in blue light. For growth under a canopy, where blue light is diminished, CRY1 and CRY2 perceive this change and respond by directly contacting two bHLH transcription factors, PIF4 and PIF5. These factors are also known to be controlled by phytochromes, the red/far-red photoreceptors; however, transcriptome analyses indicate that the gene regulatory programs induced by the different light wavelengths are distinct. Our results indicate that CRYs signal by modulating PIF activity genome-wide, and that these factors integrate binding of different plant photoreceptors to facilitate growth changes under different light conditions. Overall design: We performed whole-genome transcriptome (mRNA-seq) analysis on 5-day-old Arabidopsis thaliana Columbia wild-type (WT) and pif4pif5 seedlings exposed to low blue-light (LBL) or mock-treated for 1, 6 and 24 hours. In addition we performed mRNA-seq on WT, 35S::PIF4-9xMyc-6x-His-3xFlag(Flash) and 35S::PIF5-9xMyc-6x-His-3xFlag (Flash) seedlings treated with LBL or mock-treated for 16 hours.