nalyot, a mutation of the Drosophila Myb-related Adf1 transcription factor, disrupts synapse formation and olfactory memory

nalyot (nal) is a novel olfactory memory mutant of Drosophila, encoding Adf 1, a myb-related transcription factor. Following extended training sessions , Adf1 mutants show normal early memory but defective longterm memory. Adf1 shows widespread spatiotemporal expression, yet mutant alleles reveal no d iscernible disruptions in gross morphology of the nervous system. Studies a t the larval neuromuscular junction, however, reveal a role for Adf1 in the modulation of synaptic growth-in contrast to the role established for dCRE B2 in the control of synaptic function (Davis et at., 1996). These findings suggest that Adf1 and dCREB2 regulate distinct transcriptional cascades in volved in terminal stages of synapse maturation. More generally, Adf1 provi des a novel link between molecular mechanisms of developmental and behavior al plasticity.