Notch signaling plays well described roles in developmental cell fate decisions, in the regulation of stem cell proliferation and in numerous diseases. However, Notch signaling is also critical for the function of adult neurons. Notch plays a role in memory retention in mice and Drosophila, yet the targets of Notch signaling in neurons are unclear. We have demonstrated that the C. elegans lin-12 Notch receptor acts in adult animals to modulate behavior. In the studies proposed here, we will identify the molecular pathways by which Notch signaling alters neuronal function and behavior using the powerful genetic techniques available in C. elegans. In a pilot screen, we identified five genes expressed in the nervous system that are likely direct targets of Notch. All five genes encode proteins that are likely critical for Notch signaling in vertebrate neurons as well. In this proposal, we address the mechanisms and pathways by which these Notch target genes act in the adult nervous system to regulate neuronal activity and behavior.