Fig. S9.
In vitro phosphorylation of AtPIP2;1 peptides by BAK1. (A) Phosphorylation by purified BAK1 of native or mutated peptides from the loop B and C-terminal region of AtPIP2;1. Incorporated ATP (±SE) from n = 4 independent experiments was normalized to the signal observed with the reference myelin basic protein (MBP). (B) The loop B AtPIP2;1 peptide was incubated at the indicated concentrations, in the presence of labeled ATP and purified BAK1. The mean incorporated ATP (±SE) was determined from four independent experiments, each with 2–3 technical replicates. Calculated affinity (Km) is = 18.2 ± 5 μM.