Alpha-cardiac actin promoter drives muscle specific expression. (a) Representation of the Car-GFP construct, where the muscle specific "alpha-cardiac actin" promoter (Car) is driving the expression of GFP. (b, c) Car-GFP F0 transgenic animals generally show specific and strong GFP expression in muscle fibres of the hindlimbs (b) and the tail (c). n = 25 animals. (d) At 4 dpa, many GFP+ cells are observed in the tail regenerate of a Car-GFP F0 transgenic tadpole (arrows). Dashed line: amputation plane.