The present invention relates in part to isolated nucleic acid molecules (polynucleotides) which encode Drosophila melanogaster ligand-gated ion channel proteins. The present invention also relates to recombinant vectors and recombinant hosts which contain a DNA fragment encoding Drosophila ligand-gated ion channel proteins, substantially purified forms of associated Drosophila ligand-gated ion channel proteins and recombinant membrane fractions comprising these proteins, associated mutant proteins, and methods associated with identifying compounds which modulate associated Drosophila melanogaster ligand-gated ion channel proteins, which will be useful as insecticides.