Alcohol is one of the most widely used drugs in the U.S. and long-term abuse is devastating to individuals and society. Unfortunately, few therapeutics are available to treat the effects of alcohol addiction and the molecular mechanisms causing long-term abuse are still unclear. To identify novel genes that regulate ethanol sensitivity, we conducted a genetic screen in Drosophila melanogaster and identified a mutation in the Ras suppressor 1 (Rsu1)-encoding icarus (ics) gene. Fly strains carrying a mutation in the ics gene are resistant to the activating and sedating effects of alcohol. In this proposal, I hypothesize that ics is required in the CNS to mediate alcohol-induced responses and works through the integrin and EGFR signaling pathways to exert its effect. In this proposal, I will test hypothesis using genetic, biochemical and behavioral approaches to elucidate the molecular role of ics in regulating alcohol-induced responses.
In aim 1 I will determine whether ics is important in the adult central nervous system for normal alcohol responses.
In aim 2, to determine whether ics exerts its effect through the integrin and EGFR/ERK pathways, I will test genetic interactions between ics and mutants in these receptors and their downstream signaling genes, and ask whether those mutations modify the ics ethanol- resistance. Lastly, to identify the neurocircuit in the fly brain affecting alcohol- induced behaviors, I will generate novel enhancer-Gal4 lines with specific expression in the fly brain, and assess if they affect alcohol responses. In addition, I will test whether inhibition of ics in these Gal4 lines affects alcohol hyperactivity or sedation using RNAi mediated knockdown. Findings from this proposal will improve our comprehension of the molecular mechanism(s) of alcohol behavioral responses and help to create better treatments for addiction.

Public Health Relevance

Alcoholism is a devastating disorder that significantly contributes to mortality, disability, and to healthcare costs. The goal of the proposed research is to characterize the role of the ics gene, encoding a Ras tumor suppressor associated with human alcohol abuse, in alcohol-induced behaviors in Drosophila. In conducting this research, we hope to identify risk factors for the development of alcoholism, as well as provide leads for the development of new therapeutic strategies aiding in the treatment of alcohol use disorders.

Agency
National Institute of Health (NIH)
Institute
National Institute on Alcohol Abuse and Alcoholism (NIAAA)
Type
Predoctoral Individual National Research Service Award (F31)
Project #
1F31AA021340-01
Application #
8320601
Study Section
Health Services Research Review Subcommittee (AA)
Program Officer
Reilly, Matthew
Project Start
2012-09-01
Project End
2014-08-31
Budget Start
2012-09-01
Budget End
2013-08-31
Support Year
1
Fiscal Year
2012
Total Cost
$29,516
Indirect Cost
Name
University of Texas Sw Medical Center Dallas
Department
Psychiatry
Type
Schools of Medicine
DUNS #
800771545
City
Dallas
State
TX
Country
United States
Zip Code
75390
Gonzalez, D A; Jia, T; Pinzón, J H et al. (2018) The Arf6 activator Efa6/PSD3 confers regional specificity and modulates ethanol consumption in Drosophila and humans. Mol Psychiatry 23:621-628
Ojelade, Shamsideen A; Acevedo, Summer F; Kalahasti, Geetha et al. (2015) RhoGAP18B Isoforms Act on Distinct Rho-Family GTPases and Regulate Behavioral Responses to Alcohol via Cofilin. PLoS One 10:e0137465
Ojelade, Shamsideen A; Jia, Tianye; Rodan, Aylin R et al. (2015) Rsu1 regulates ethanol consumption in Drosophila and humans. Proc Natl Acad Sci U S A 112:E4085-93
Peru Y Colón de Portugal, Raniero L; Ojelade, Shamsideen A; Penninti, Pranav S et al. (2014) Long-lasting, experience-dependent alcohol preference in Drosophila. Addict Biol 19:392-401
Ojelade, Shamsideen A; Acevedo, Summer F; Rothenfluh, Adrian (2013) The role of the actin cytoskeleton in regulating Drosophila behavior. Rev Neurosci 24:471-84
Ojelade, Shamsideen A; Rothenfluh, Adrian (2009) Addiction: flies hit the skids. Curr Biol 19:R1110-1