DEVELOPMENTAL BIOLOGY 131,439-454 (1989) Genetic Analysis of Muscle Development in Drosophila melanogaster

The different horacic muscles of Drosophila are affected specifically in the mutants: stripe (sr), erect wing (ewg), vertical wings (vtw), and?zanjumper (nj). We have tested the extent of this specificity by means of a genetic analysis of these loci, multiple mutant combinations, and gene dosage experiments. A quantitative, rather than a qualitative, specificity is found in the mutant phenotypes. All muscles are altered by mutations in any given gene, but the severity of these alterations i muscle specific. The locus stripe seems to have a polar organization where different allelic combina-tions show quantitative specificity in the muscle affected. In addition to the muscle phenotypes, neural alterations are detected in these mutants. The synergism found between ewg, vtw and ewg, sr as well as the dosage ffect of the distal end of the X chromosome upon the expression of ewg and sr suggests the existence of functional relationships among the loci analyzed. 9 1989 Academic Press, Inc