A Genetic Approach to the Study of Neurogenesis and Myogenesis

Extensive sequences of morphological differentiation have beendescribed for Drosophila melanogaster neurogenesis and myogenesis.Neuroblasts and myoblasts become determined in the blastodermor shortly thereafter. Each blast cell will then morphologicallydifferentiate in vitro in sequences that closely resemble theevents in vivo. Functional neurons, muscle cells and neuromuscularjunctions form and these have normal biochemical and ultrastructuralcharacteristics. A mutant hunt was conducted which was designedto generate mutations specific to neurogenesis or myogenesis.One mutation was recovered that apparently interfered only withmyogenesis. The frequency of recovered mutations that affectedcell differentiation was low and led to estimates that relativelyfew genes are required to preserve the structural integrityof cells during neurogenesis and myogenesis.