Expression of the CBF genes over 24 hours in the cold. Kinetics of induction of CBF1, 2 and 3 by cold. RNA was prepared by protocol 2 (see Methods) and PCR was performed on the ABI 7900 HT platform. For each gene, seven accessions were analyzed by Q-PCR: 157 AV (Ita-0), 163 AV (Can-0), 166 AV (Cvi-0), 186 AV (Col-0), 229 AV (Rld-2), 231 AV (Rub-1), and 233 AV (Sah-0). Sensitive accessions are in red and tolerant ones in blue. Time points shown are 1 h, 3 h, 6 h and 24 h after transfer to 5°C. Average standard errors in the determination of the expression of the different genes varied between 0.38 Ct and 0.47 Ct.