MYOGENESIS AND MUSCLE PATTERNING IN DROSOPHILA

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