Fig. 5

GFP diffusion in the root meristem of Arabidopsis thaliana is restricted in 3% PEG and 75 mM sodium chloride. a Seeds expressing pSUC2::GFP were grown on ATS control media, ATS supplemented with 3% polyethylene glycol (PEG) or with 75 mM NaCl. Roots were collected at 4 days post-germination (4 dpg) and counterstained with propidium iodide (PI). Images were sequentially collected at 561 nm (PI shown in grey) and 488 nm (green: GFP). Estimated water potential (MPa, see main text) is labelled on top of the representative pictures. b, c Transects highlighted by magenta boxes in (a) were used to determine GFP fluorescence profiles using mean grey values (AU: arbitrary units). b shows transects across the transition zone (TZ) while (c) shows transects rootward starting from the transition/proliferation zone (TZ/PZ) towards the root tip. d-f Similar experiments were carried out with seedlings germinated on ATS media and transferred for 1 day (1dpt) to 3% PEG or 75 mM NaCl. Scale bar = 100 μm. Charts show traces representing aggregate min-max normalised GFP fluorescence along the transect (mean ± SE, N indicated in the key)