Laminin and Hh signaling act synergistically in fast-twitch muscle cell elongation. Side views, anterior left, dorsal top, 48 hpf embryos stained with phalloidin to visualize actin. White arrows point to elongated fast-twitch muscle fibers. White arrowheads points to short, round fast-twitch muscle cells. Panels E-H are higher magnification images from a different experiment than panels A-C. A-C, E-G: Fast-twitch fibers are long in wild-type, lam gamma1 mutant embryos, and CyA-treated wild-type embryos at 48 hpf. D, H: Fast-twitch cells are shorter and round in CyA-treated lam gamma1 mutant embryos. I, J: Three-dimensional projections of dextran-filled cells show highlight the short fast cells in CyA-treated laminin gamma1 mutant embryos.