Myogenesis and muscle patterning in Drosophila.

Subsets of differentiating muscles in the Drosophila embryo express putative transcription factors, such as S59 and vestigial. These genes may control the development of specific muscle properties. Myogenesis in embryos mutant for wingless is grossly deranged. Mesodermal expression of S59 is lost, whereas some vestigial-expressing muscles develop. wingless dependence and independence of specific muscle subsets correlates with an early derangement of twist expression in wingless mutants. The possible role of the ectoderm in patterning Drosophila mesoderm is discussed.