(A) Protoplasts from wt hypocotyls were left untreated (control), or were treated with 1 nM PSK-α, 1 µM FC, or 1 nM PSK-α+1 µM FC at t = 0. Results are averages (±SE) from 4 to 8 protoplasts analyzed per genotype or treatment. Protoplast expansion was not significantly different between effector treatments (P<0.05, 2-sample t-test). (B) WT protoplasts were pre-treated with 0.5 mM ortho-vanadate for 1 h. At t = 0 min 1 nM PSK-α, 1 µM FC, or 1 nM PSK-α+1 µM FC were added, or protoplasts remained untreated (control). Results are averages (±SE) of 3 or 5 protoplasts analyzed per treatment and genotype. (C) Protoplasts from pskr1-3 hypocotyls were treated with or without 1 µM FC at t = 0. Protoplasts showed a wt swelling response (see A; P<0.05, 2-sample t-test).