CrcEP1084/CrcEP3167 flies reproducibly exhibit a reduction in avoidance of the olfactory repellant 3-octanol compared to wild-type flies in an olfactory T-maze. A similar avoidance is seen in Crc10d/CrcEP3167 flies. In contrast, flies that are heteroallelic for CrcEP979/CrcEP3167 have little or no odour avoidance defects and the behaviour of Crc10rv/CrcEP3167 flies in response to 3-octanol is indistinguishable from wild type. CrcEP1084/CrcEP3167 flies also exhibit a reduction in avoidance of the olfactory repellants benzaldehyde and 4-methylcyclohexanol. Reduced avoidance of 4-methylcyclohexanol is most pronounced at low concentrations. However, CrcEP1084/CrcEP3167 flies are attracted to the olfactory attractants ethyl acetate and isoamyl acetate to the same extent as wild-type flies. The exploratory activity and climbing ability of CrcEP1084/CrcEP3167 mutant flies is not significantly different from wild type, while the climbing ability of CrcEP3167/Crc10d flies is actually greater than wild-type flies. Additionally, CrcEP1084/CrcEP3167 mutant flies have a normal electroantennogram amplitude in response to both 3-octanol and 4-methylcyclohexanol. Areas of the brain important for locomotion and olfaction in CrcEP1084/CrcEP3167 mutants have no obvious morphological differences from the wild type.
