Mutation of linotte causes behavioral defects independently of pigeon in Drosophila

The Drosophila linotte1 mutation was isolated from a genetic screen designed to identify learning and memory genes. For some authors, this mutation affects a novel gene specifically involved in adult learning and memory, whereas for others, it is an allele of the derailed receptor tyrosine kinase gene (the linotte/derailed gene) involved in nervous system development. Here, we show that the original derailed mutation induces a memory phenotype. We also report that a new null mutation, lioexc21, affecting specifically the linotte/derailed gene causes behavioral defects, which can be partially rescued by expression of a lio+/drl+ transgene. The data presented here suggest that the memory phenotype of linotte and derailed mutants is a consequence of abnormal brain development due to loss of function of the linotte/derailed encoded receptor tyrosine kinase.