MOLECULAR-CLONING OF LINOTTE IN DROSOPHILA - A NOVEL GENE THAT FUNCTIONS IN ADULTS DURING ASSOCIATIVE LEARNING

The linotte (Iio) gene was identified in a screen for mutations that disrupted 3 hr memory after olfactory associative learning, without affecting the perception of odors or electroshock. The mutagenesis yielded a transposon-tagged gene disruption, which allowed rapid cloning of genomic DNA. The Iio transcription unit was identified via rescue of the Iio(1) learning/memory defect by induced expression of a Iio(+) transgene in adults. The perception of odors or electroshock remained normal when the Iio(+) transgene was expressed in these Iio(1) flies. Learning/memory remained normal when the Iio(+) transgene was expressed in wild-type (Iio(+)) flies. The Iio gene produces only one transcript, the level of expression of which varies throughout development. Sequence analysis indicates that Iio encodes a novel protein.