Because activation of the mushroom body was required for the development of conditioned preference for ethanol, we assayed a collection of fly strains with known expression in the mushroom body to search for novel genes involved in ethanol reward. We show that sca is required for the formation of memories of ethanol reward. sca is a fibrinogen-related secreted peptide that plays a role in neurogenesis, spacing differentiation and boundary formation via a Notch (N)-dependent pathway4,5. During development, Sca associates with N, and can stabilize N protein at the cell surface, thus sharpening proneural cluster boundaries and ensuring the establishment of single pioneer neurons5.
