High Auxin and High Phosphate Impact on RSL2 Expression and ROS Homeostasis Linked to Root Hair Growth in Arabidopsis Thaliana

The study explored the effects of high auxin and phosphate (Pi) levels on root hair growth in Arabidopsis thaliana, focusing on the role of transcription factors RSL4 and RSL2 and reactive oxygen species (ROS) homeostasis. It was found that high Pi levels repress RSL4 and RSL2 expression and root hair growth, while high auxin levels promote growth by activating RSL2 expression and ROS production. The study also demonstrated that inhibiting ROS production blocked the growth-promoting effects of auxin, indicating the importance of ROS homeostasis in this process. Overexpression of RSL4 or ARF5 could partially counteract the growth repression caused by high Pi. The results suggest a complex interplay between auxin, Pi, and ROS homeostasis, with RSL2 playing a central role in mediating root hair growth under these conditions.