<i>Drosophila</i> Odorant Receptor Or22a/Orco (IMAGE) Max Planck Institute for Chemical Ecology Caption The antennae of the fruit fly Drosophila melanogaster are shown schematically in dark yellow. Dark red: odor molecules. Right: The odorant receptors studied are protein dimers consisting of the odorant receptor Or22a and the co-receptor Orco; they mediate very sensitive responses to odor molecules. Above: State of sensitization -- weak ion flow caused by cAMP; below: signals are "switched through" in the receptor system resulting in opening of the ion channel and electric signal transduction. The pictures are taken from the animation. Credit Graphics: Dieter Wicher, Max Planck Institute for Chemical Ecology. Animation: Moves Like Nature, Kimberly Falk, Jena Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.