Fig 1.

The expression profile of tadpoles transgenic for pCar/GFP. (a) Ventral view of the head region of a 1-wk-old tadpole expressing GFP in cardiac and skeletal muscle. (b) GFP expression in the muscle of the developing limb at NF stage 54. (c) GFP expression in the limb muscle of a juvenile frog. (d) GFP expression in muscle fibers in the middle of the tail region of a stage 57 tadpole. (e) GFP expression in the mid-tail region of a stage 63 tadpole, demonstrating the loss of GFP fibers in the fast muscle chevrons. (f) GFP expression in the slow muscle cords of the tail in a stage 64 tadpole. (g) Loss of GFP-labeled muscle fibers in the tail of a stage 63 tadpole. [Bars = 500 μm (a, b, and f) and 1 mm (c–e and g).]