A deletion created by ends-out homologous recombination removes the Obp49a coding sequence and replaces it with GAL4 and mini-white coding sequences.
Mutant flies show impaired avoidance of a wide array of bitter tastants including papaverine, berberine, denatonium, quinine, caffeine and strychnine in a two-way choice taste assay.
Application of sucrose to L-type sensilla or aversive chemicals to S-type sensilla results in virtually the same frequencies of action potentials in mutant and wild-type flies.
The ability of a number of bitter chemicals (papaverine, berberine, denatonium, quinine, caffeine and strychnine) to inhibit sucrose-induced action potentials in L-type sensilla is greatly reduced in mutant flies compared to wild type.
