Figure 3.

GCAP2 promotes CNG channel current in low Ca²⁺. Normalized (Norm.) r_max, the saturated photoresponse amplitude of dark-adapted cones, of control Gnat1^−/− (black), Gcaps^−/− Gnat1^−/− (green), and Gcap1^−/− Gnat1^−/− (red) mice in normal Ca²⁺ (at t = 0 s) and during low-Ca²⁺ exposure (t > 0 s) is shown. The values for r_max were normalized to their respective value in normal Ca²⁺ just before the switch to low Ca²⁺ at t = 0 s. n = 3 mice (six retinas) for each genotype. Error bars give S.E.