The timing of sleep behavior is controlled by a feedback loop involving expression of genes of the `molecular clock'. How this clock regulates sleep behavior is poorly understood. This project is focused on understanding how the timing mechanism regulates sleep behavior at a single neuron resolution. We use the lethargus stage in the roundworm C. elegans as a model for sleep. Lethargus is a quiescent state that shows both behavioral and molecular genetic similarities to mammalian sleep. We have identified a sleep-inducing neuropeptide called NLP-22, which is expressed in one pair of neurons, the RIAs. We will use a combination of genetic, optical, and behavioral tools to study the mechanism by the RIA neurons integrate timing molecular signals with sleep signals from other neurons and how they ultimately affect peripheral target organs.
In Aim 1, we focus on understanding the role of the RIA neurons in sleep regulation.
In Aim 2, we investigate the mechanism by which NLP-22 induces feeding quiescence. And in Aim 3 we use a discovery approach to identify new somnogenic signals. Our project makes use of the powerful genetic and optical tools available in C. elegans to illuminate the molecular mechanism of sleep regulation within a defined neural circuit.

Public Health Relevance

The use of model organisms such as C. elegans to understand the genetic basis of sleep is improving our understanding of human sleep disorders. Our research will identify the mechanisms by which a sleep- promoting nerve cell works and will identify additional sleep-promoting genes. Discoveries made here can be later translated to other animals with the ultimate goal of finding new molecular targets for diagnosing and treating sleep disorders.

National Institute of Health (NIH)
National Institute of Neurological Disorders and Stroke (NINDS)
Research Project (R01)
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Neurodifferentiation, Plasticity, and Regeneration Study Section (NDPR)
Program Officer
He, Janet
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University of Pennsylvania
Schools of Medicine
United States
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