Communication between neurons occurs via connections called synapses and is mediated by chemical messengers (neurotransmitters) and their receptors (neurotransmitter receptors). Controlling levels of neurotransmitter receptors at synapses controls the intensity of neuronal communication, which is important for learning, memory and cognition. This project studies how a factor secreted from muscle regulates levels of neurotransmitter receptors at synapses in neurons that control movement in the roundworm Caenorhabditis elegans. Although the genes and molecular pathways that regulate neurotransmitter receptors exist in vertebrates like humans, the proposed studies are conducted using roundworms because they have a compact and defined nervous system, are amenable to genetic manipulation, and are transparent, enabling the study of the entire muscle-to-neuron pathway in live, intact animals. Muscles are known to release hundreds of factors during contraction that have impacts on other organs, including the brain, but exactly what these factors are doing at the molecular level is not known. Results from this study will advance our scientific understanding of how muscle releases factors that signal to the brain to control communication between neurons. This research may also identify molecular pathways relevant for understanding the beneficial effects of exercise on learning, memory and cognition. An outreach plan will develop a hands-on lab research module for undergraduates to teac