The long-term goal of this research is to study the dynamics of neurotransmitter signaling in the central nervous system of Drosophila melanogaster, the fruit fly. The specific goal of this project is to develop a microelectrode method to measure the real-time release and clearance of serotonin in an intact fruit fly nervous system. The fruit fly is a popular model system for biologists because of the ease of making genetic mutations and its homology with higher order organisms, including similar neurotransmitter systems. The small size of the fly central nervous system (8 nL) has precluded real-time studies of neurotransmitter release and uptake. This study has implications for human health because serotonin is an important neurotransmitter whose signaling is implicated in mental illnesses, including depression and drug abuse. However, the mechanisms for regulation of serotonin concentrations are not well understood.
The specific aims are: 1. To characterize real-time, endogenous serotonin release and uptake in individual Drosophila larva. Genetically modified flies with a blue-light sensitive channel will be used to specifically elicit serotonin release. This technique will be used to test hypotheses about the effects of cocaine administration on serotonin transporter activity and the effects of genetic manipulations on neurotransmitter release. 2. To compare the regulation of serotonergic and dopaminergic signaling in Drosophila. Repeated stimulations will be used to assess the importance of synthesis and recycling in maintaining release. 3. Development of a rapid assay for serotonin transporter activity in Drosophila. Small amounts of serotonin will be pressure ejected into the nerve cord and then detected at the microelectrode. This technique will allow tests of hypotheses about the effect of pharmacological agents or mutations of the serotonin transporter on serotonin signaling. These experiments will result in assays for the fly that will be valuable for screening genetic factors that regulate neurotransmitter levels, resulting in a better fundamental understanding of the time course of neurotransmission.
This research will lead to a better understanding of the basic neurobiology of serotonin, an important modulatory neurotransmitter. We will study how drugs and genetic mutations affect serotonin signaling in the fruit fly nervous system. These studies are important because many psychiatric disorders, including depression and obsessive compulsive disorder, are treated by drugs that target the serotonergic system, but the mechanism of action of these drugs is not well understood.
|Zestos, Alexander G; Jacobs, Christopher B; Trikantzopoulos, Elefterios et al. (2014) Polyethylenimine carbon nanotube fiber electrodes for enhanced detection of neurotransmitters. Anal Chem 86:8568-75|
|Jacobs, Christopher B; Ivanov, Ilia N; Nguyen, Michael D et al. (2014) High temporal resolution measurements of dopamine with carbon nanotube yarn microelectrodes. Anal Chem 86:5721-7|
|Xiao, Ning; Privman, Eve; Venton, B Jill (2014) Optogenetic control of serotonin and dopamine release in Drosophila larvae. ACS Chem Neurosci 5:666-73|
|Vickrey, Trisha L; Xiao, Ning; Venton, B Jill (2013) Kinetics of the dopamine transporter in Drosophila larva. ACS Chem Neurosci 4:832-7|
|Vickrey, Trisha L; Venton, B Jill (2011) Drosophila Dopamine2-like receptors function as autoreceptors. ACS Chem Neurosci 2:723-729|
|Jacobs, Christopher B; Vickrey, Trisha L; Venton, B Jill (2011) Functional groups modulate the sensitivity and electron transfer kinetics of neurochemicals at carbon nanotube modified microelectrodes. Analyst 136:3557-65|
|Fang, Huaifang; Vickrey, Trisha L; Venton, B Jill (2011) Analysis of biogenic amines in a single Drosophila larva brain by capillary electrophoresis with fast-scan cyclic voltammetry detection. Anal Chem 83:2258-64|
|Borue, Xenia; Condron, Barry; Venton, B Jill (2010) Both synthesis and reuptake are critical for replenishing the releasable serotonin pool in Drosophila. J Neurochem 113:188-99|
|Vickrey, Trisha L; Condron, Barry; Venton, B Jill (2009) Detection of endogenous dopamine changes in Drosophila melanogaster using fast-scan cyclic voltammetry. Anal Chem 81:9306-13|