Figure 4.

Cold responses mediated by ARK in P. patens. (A) Changes in freezing tolerance during cold acclimation in WT and AR7 (ark^S532F). Protonemata that had been cold-acclimated for the indicated days were frozen to −3°C and injury rate was estimated by measurement of electrolyte leakage after thawing. Error bars indicate standard error of the mean. *P < 0.05 in the t test (n = 3) compared with non-acclimated protonemata of each line. (B) Immunoblot analysis with anti-phospho-Ser1029 (P-S1029) and anti-ARKc antibodies. Coomassie Brilliant Blue staining of the large subunit of ribulose bisphosphate carboxylase (rbcL), results of immunoblot analysis for cold-induced 17B9 protein, and SnRK2 activity analyzed by an in-gel kinase assay are also shown.