UC San Diego

ABSTRACT OF THE THESIS

Sleep and Memory Regulation through Cholinergic and Dopaminergic Signaling in

qvr/sss Neurons

by

Veronica Qiao Lin

Master of Science in Biology

University of California San Diego, 2020

Professor William Joiner, Chair

Sleep is known to affect memory, but the exact relationship is unclear. My thesis aims to elucidate this relationship and identify key contributors to the regulation process. I studied the correlation between sleep and memory phenotypes in sssP1 and DATfmn fly mutants via the Drosophila Activity Monitoring system and the Proboscis Extension Reflex assay, respectively; rescued both phenotypes by various Gal4>UAS and Gal4>RNAi combinations; and identified several molecules that play important roles in the regulation of sleep and memory. I established that healthy sleep behavior is positively correlated with intact memory function and chronic sleep deprivation is linked to memory deficits. By studying sssP1 and DATfmn mutants, I found that both QVR/SSS and DAT for regular sleep and memory functions and 11E12, 12C10, 109(2)80, and piezo neurons are important loci for the sleep and memory effects of qvr/sss.

In these qvr/sss neurons, I found that knocking down either Dop1R2 or D3 is sufficient to rescue the phenotypes of sssP1 and DATfmn mutants. The results suggest that Dop1R2 and D3 may function in parallel in qvr/sss neurons, and dopaminergic and cholinergic signaling may converge onto these qvr/sss neurons to regulate sleep and memory. Further, D3 is regulated by two molecules with opposing effects; QVR/SSS inhibits D3 activity while dNACHO promotes it. Collectively my data suggest that sleep and memory functions are regulated by qvr/sss neurons by coordinated dopaminergic and cholinergic mediation.