Figure 7.

Electrophysiological characterization of a putative Arabidopsis cyclic nucleotide-gated channel (“AtCNGC1”) expressed in oocytes. Command voltages were applied in 20-mV steps between −60 and −160 mV. All recordings were made in the two-electrode configuration, and are presented without leak subtraction. In all cases, [dibutyryl-cAMP] was 5 mm, and the standard oocyte bath solution was used (i.e. with 96 mm K⁺). AtCNGC1 showed no (inward) currents before addition of dibutyryl-cAMP to the perfusion bath solution (▴). Currents were evident 3 h after addition of dibutyryl-cAMP to the perfusion bath solution (●) in this experiment. Water-injected oocytes displayed no inward currents after exposure to dibutyryl-cAMP for 3 h (○). Results are presented as means (n = 4) ± se. The insert shows representative time-dependent currents recorded from oocytes expressing AtCNGC1 before (bottom of insert) and 3 h after addition of dibutyryl cAMP (top of insert).