903V Poster - 14. Neural circuits and behavior
Wednesday April 06, 4:00 PM - 7:00 PM

Authors:
LINNI JIN ¹; Seungyun Yu ²; Jae Young Kwon ²; Seok Jun Moon ¹

Affiliations:
1) Department of Oral Biology, BK 21 FOUR Project, Yonsei University College of Dentistry, Seoul, Korea; 2) Department of Biological Sciences, Sungkyunkwan University, South Korea

Keywords:
n. chemosensation; j. ion channels

Taste allows animals to discriminate nutritious food from toxic substances. Drosophila gustatory receptors (GRs) for aversive chemicals are relatively well characterized; complexes consist of three or four GRs for detecting bitter chemicals. Sweet gustatory receptor neurons (GRNs) express eight closely related GRs: Gr5a, Gr61a, Gr64a, Gr64b, Gr64c, Gr64d, Gr64e, and Gr64f. However, little is known regarding the molecular basics of how sweet GRs detect sugars. Loss of function of Gr64 cluster GRs causes distinct phenotypes, presumably due to the polycistronic expression of mRNA. In addition, findings on ectopic expression of sugar receptors are contradictory to previous studies. To elucidate the function of sugar GRs, we employed the GAL4/UAS overexpression system to overexpress one or a combination of Gr64 genes in the Gr64 null deletion mutant to examine the function of the Gr64 genes. However, this approach also resulted in results inconsistent with the loss of individual Gr64 genes. To overcome the potential artifacts of overexpression of sweet GRs, we generated transgenes to express individual Gr64 cluster genes under the control of the 5′ regulatory element of the Gr5a gene, to mimic the endogenous expression of each Gr64 gene. We will present our progress on exploring the necessity and sufficiency of sweet GRs.