Fig. 1. Differentiation of mesodermal derivatives in wild-type and minc mutant embryos. (A,B) Anti-Krüppel staining confirms normal distribution of Kr-expressing founder cells in minc mutant embryos. Stage 14 embryos: wild type (A) and minc[A388] (B). (C) Diagram to show normal pattern of Kr-expressing muscles (black) in an embryonic hemisegment. (D-F) Anti-myosin staining in wild-type (D) and mutant (E,F) embryos to show normal muscle pattern (D), complete lack of myoblast fusion and differentiating mononucleated muscles (E,F) and normal heart (F). Inset in D shows enlarged view of pharynx and inset in F shows enlarged view of unfused pharyngeal muscles in this minc[A388] embryo. Note absence of myosin expression in unfused fusion-competent cells in E and F. (G-I) Expression of Dmef2 in wild-type (G), minc[A388] (H) and mbc1 (I) embryos. Note absence of Dmef2 expression in fusion-competent myoblasts in H; compare with expression of Dmef2 in these cells in I. Insets show enlarged views of regions indicated by asterisks in F-I.