Expression of ARR5, ARR6, and ARR7 in response to cold in 35S:AtCKX transgenic Arabidopsis deficient in cytokinins compared with the wild type. Eleven-day-old light-grown seedlings were treated at 1 °C for 1, 2, or 4 h, and the total RNA isolated was subjected to real time RT-PCR. The treatment and analysis of the samples were done as described in the Fig. 2 legend. The numbers on top of the bars indicate fold-induction relative to the control sample at 0 h. Open and closed bars represent the Col-0 wild type and 35S:AtCKX2-2 transgenic Arabidopsis, respectively. ** denotes statistically significant changes with p < 0.01 compared with the wild type.