Figure 5.

Expression of CYP735A2 and ABCG14 in cytokinin biosynthetic and signaling mutants treated with high CO₂ or sugars. (a,c) Wild-type (Col-0), ipt3 ipt5 ipt7 (ipt357), ahk2 ahk3 (ahk23) and ahk3 ahk4 (ahk34) seedlings grown on 1/2MS agar plates at 280 ppmv CO₂ for 12 days were exposed to 280 ppmv or 780 ppmv for six hours and then roots were harvested. (b,d) ipt357 seedlings were transferred to new plates containing 90 mM of sorbitol (Sorb), mannitol (Man), sucrose (Suc) or glucose (Glc), or without any sugar (-sugar). Roots were harvested after six hours. Expression levels were analysed by quantitative real-time PCR and normalized using At4g34270 as an internal control. Error bars represent standard deviation of three biological replicates. Different lower-case letters indicate statistically significant differences as indicated by Tukey’s HSD test (p < 0.01).