Transcriptional Regulation of Sunflower Heliotropism and Phototropism

Sunflowers are famous for their ability to track the sun throughout the day, and then reorient at night to face east the following morning. This process, termed heliotropism, is generally believed to be a specialized form of phototropism; however, the underlying mechanism is unknown. To better understand heliotropism we used RNA sequencing to compare the transcriptional profiles of sunflower stems during heliotropism, and blue light-induced phototropism. Comparative gene expression profiling analysis of RNA-seq data from stem tissue of sunflowers undergoing either phototropism or heliotropism.