Roles of proteome dynamics and cytokinin signaling in root-to-hypocotyl ratio changes induced by shading roots of Arabidopsis seedlings

Seeds of Arabidopsis thaliana ecotype Columbia (Col-0) were surface-sterilized (using 75 % ethanol) and sown on Murashige and Skoog medium (pH 5.7) supplemented with 3 mM morpholinoethane sulfonic acid, solidified with 1% (w/v) agar and stratified at 4 °C for 48 h. Petri dishes were covered by a layer of black stretch shrink wrap film (black foil) and aluminum foil and incubated at 21°C/19°C day/night temperatures, with a 16 h photoperiod (photosynthetic photon fluence rate of 20 μmol m-2 s-1 over the waveband 400-700 nm) for 7 d in an AR-36L growth chamber