A SINGLE GUSTATORY RECEPTOR CAN SWITCH THE INCENTIVE SALIENCE OF A SPECIFIC REWARD

Animal behavior is shaped by both evolution and individual experience. The selection of an appropriate response to an external stimulus represents a fundamental brain function. Reward influences both immediate and long-term animal behavior. Although much work has been done on understanding the nature and circuit mechanisms of reward, how reward perception evolves to drive species-specific long-term behavioral changes remains unknown. Previously, we found that Drosophila melanogaster innate responses to a reward can be distinct from how robustly the reward would produce long-term change in behavior. Innately, when given the choice flies prefer to consume D-arabinose over L-arabinose, but more reliably form long-term memories of L-arabinose. Importantly, D- and L-arabinose are both innately attractive to hungry flies and non-nutritious. To understand the ecological, neuronal, and molecular basis of this dissociation between immediate perception of reward from its long-term consequence we screened 28 divergent Drosophilidae species living in different ecological niches. Remarkably, we found that unlike D. melanogaster, D. mojavensis prefers L-over D-arabinose, but D-arabinose is more effective as a rewarding stimulus for long-term associative memory. In both species Gr43a receptor is important for long-term, but not short-term memory. Substitution of the D. melanogaster Gr43a with D. mojavensis Gr43a does not affect immediate preference of D. melanogaster to D-arabinose or short-term memory but switches the long-term memory; instead of L-now D-arabinose produces better memory. Dissecting the neuronal circuit and assessing neuronal activity by calcium imaging we found that response of two Gr43a expressing neurons in the leg switches upon receptor substitution. These results demonstrate how sensory receptors can dissociate reward perception that guides immediate and long-term behavior. This work also demonstrates how polymorphism of a single sensory receptor can allow evolution of long-term learned behavior utilizing the inherent plasticity of the same neuronal circuit.

Grantor dc:publisher

University of Kansas

Year dc:date.issued

2024

Author dc:creator

• Perez-Sanchez, Consuelo

Advisors dc:contributor.advisor

• Si, Kausik K.
• Blanco, Gustavo G.

• Neurosciences
• Biology
• Drosophila
• Evolution
• Gustatory Receptors
• Incentive Salience
• Memory
• Reward

Language dc:language.iso

en

Dc Identifier Other

http://dissertations.umi.com/ku:19413

OAI identifier oai:identifier

oai:kuscholarworks.ku.edu:1808/38365