Protein engineering and the study of muscle contraction in Drosophila flight muscles.

We describe an experimental approach to the use of genetics to study muscle contraction in Drosophila melanogaster. Mutations induced by in vitro mutagenesis are inserted into the genome of flies using P-element mediated transformation, permitting the effects of the mutant genes to be studied in vivo in the indirect flight muscles (IFMs). Details of how mechanical experiments can be performed on skinned IFMs, despite their small size, are provided. The effects of two in vitro actin mutations, G368E and E316K, are described. The problems of performing biochemical and biophysical experiments on the IFMs and their myofibrillar proteins are described, together with indications as to how these may be overcome.