Figure 2.

Involvement of reactive oxygen species (ROS) metabolism in root cell elongation and differentiation. The left‐hand side of the figure shows the how ROS metabolism is regulated and coordinated with other signals to promote root cell elongation, whereas the right‐side of the figure shows the involvement of these molecules in root cell differentiation. Arrows with cyan outer glow indicate a direct function of ROS in cell wall modification, whereas arrows with a magenta outer glow indicate their signalling role through oxidation of specific protein residues to modulate enzymatic functions. AQPs, Aquaporins; ARFs, Auxin response factors; HPCA1, Hydrogen‐peroxide‐induced Ca²⁺ Increases (a H₂O₂ plasma membrane receptor); POD, Peroxidases; R, Respiratory burst oxidase homologue; SOD, Superoxide dismutase. [Color figure can be viewed at wileyonlinelibrary.com]