PI3K activity associated with CNGA1 is independent of light and IR activation. Solubilized ROS from either dark or light-adapted mice (A) or IR wild-type (C) or IR knockout (C) mice were immunoprecipitated with anti-CNGA1 antibody or non-immune IgG. PI3K activity was measured using PI-4,5-P2 and [γ32P]ATP as substrates. The radioactive spots of PI-3,4,5-P3 were scraped from the TLC plate and counted (B, D). Data are mean ± SD (n = 3).