INNERVATION IS ESSENTIAL FOR THE DEVELOPMENT AND DIFFERENTIATION OF ASEX-SPECIFIC ADULT MUSCLE IN DROSOPHILA-MELANOGASTER

The adult abdominal muscles in Drosophila are generated de novo during metamorphosis and form a simple and characteristic pattern. Throughou t adult abdominal development there is a close association between ner ves and myoblasts, However, the role of innervation in adult myogenesi s is unclear, In males there is an additional muscle, which is unique to abdominal segment 5 (A5). This male specific muscle forms from the same pool of myoblasts as other dorsal muscles in A5 but develops seve ral distinctive characteristics. Previous work indicates the genotype of the innervation of this male specific muscle may play a crucial rol e in its proper development, although the part played by innervation i n the development of other muscles is unknown, Here we test directly t he function of innervation in adult myogenesis in general and for the development and differentiation of the male specific muscle in particu lar, After denervation at the onset of metamorphosis, muscle growth is impaired although the overall muscle pattern continues to develop, Un iquely, the male specific muscle fails to form, Our results indicate t hat there is an essential role for innervation during the period of me tamorphosis for the formation of a full complement of abdominal muscle s and for muscle growth, Furthermore, innervation is absolutely requir ed for the formation of the male specific muscle and the development o f its special characteristics.