e and f. Microscopic images of 5 DAG old roots expressing (e) PIN2::PIN2S439D-GFP and (f) PIN2::PIN2S439A-GFP 12 HAT to ammonium or nitrate amended media. "e" denotes epidermis and "c" cortex, respectively. White arrows point to PIN2-GFP protein localization on the lateral membranes. 