Purpose. Light-induced translocation of rod α-transducin (rTα, GNAT1) has been recognized as one of the mechanisms for light adaptation in rods. However, cone α-transducin (cTα, GNAT2) has not been shown to have such light-dependent redistribution. To investigate potential reasons for the restriction of cTα to the cone outer segment, the authors established a transient transgenic strategy to express cone Tα within rod photoreceptor cells, and the location of the cone Tα within rods and cones was examined under different light conditions.