Fig. 5.

Requirement of FGF8-like ligands for dorsal mesoderm differentiation. Drosophila embryos at stage 10 (A-F) or stage 13/14 (G,H) were fixed and stained with antibodies against Eve (A-F) or Lb (G,H). (A) Wild-type expression of Eve in 11 hemisegmental cell clusters (arrowheads). (B) In Df(2R)ED2238 homozygotes, Eve expression is absent. (C,D) ths⁷⁵⁹ homozygous (C) or hemizygous (D) embryos show normal Eve expression. (E,F) pyr¹⁸ homozygous (E) and hemizygous (F) embryos lack Eve-positive dorsal mesodermal precursors. (G) Wild-type cardiac Lb expression. (H) Several, but not all, cardiac Lb clusters are missing in pyr¹⁸ homozygous embryos (arrowheads).