We are broadly interested in the mechanisms of neuronal cell signaling and how these processes manifest in specific behaviors and regulate discrete aspects of physiology. In pursuit of that goal, we focus on neurotransmitters and their receptors and use the fruit fly, Drosophila melanogaster, because of the unique genetic and molecular tools available in this organism. We use a number of different cellular and molecular techniques to partner specific neuropeptides and neurotransmitters to specific “orphan” receptors. We are interested in the anatomical distribution of these receptors as they represent postsynaptic targets for specific transmitter signaling systems. We are ultimately interested in how specific receptor properties, (i.e., desensitization and signaling) contribute to neuronal physiology and on a larger scale how these properties shape a given behavior or physiology.
Johnson, EC and White, MP. 2008. Stressed-out Insects: Behavioral Modifications and Hormonal Actions. In Hormones, Brain, and Behavior, 2nd Ed. D. Pfaff Ed, in press Johnson EC, Tift FW, McCauley AK, Liu L, and Roman G. 2008. Functional characterization of kurtz, a Drosophila non-visual arrestin, reveals conservation of GPCR desensitization mechanisms. Insect Biochem. Mol. Biol., in press Isaac RE, Johnson EC, Audsley N, and Shirras AD. 2007. Metabolic inactivation of the circadian transmitter, pigment-dispersing factor, PDF, by neprilysin-like peptidases in Drosophila. J. Exp. Biol. 210: 4465-4470 Johnson EC. 2006. Post-genomic approaches to resolve neuropeptide signaling in Drosophila. In Invertebrate Neuropeptides and Hormones: Basic Knowledge and Recent Advances. Honoo Satake Ed., pgs 179-224. Birse RT , Johnson EC, Taghert PH, and Nassel DR. 2006. Widely distributed Drosophila G-protein-coupled receptor (CG7887) is activated by endogenous tachykinin-related peptides. J. Neurobiol.66:33-46. Mertens I , Vandingenen A, Johnson EC, Shafer OT, Li W, Trigg JS, De Loof A, Schoofs L, and Taghert PH. 2005. PDF receptor signaling in Drosophila contributes to both circadian and geotactic behaviors. Neuron.48:213-9. Johnson EC , Shafer OT, Trigg JS, Park J, Schooley DA, Dow JA, and Taghert PH. 2005. A novel diuretic hormone receptor in Drosophila: evidence for conservation of CGRP signaling. J Exp Biol. 208:1239-46. Johnson EC, L Bohn, and P Taghert. 2004. Drosophila CG8422 encodes a functional diuretic hormone receptor. J. Exp. Biol. 207:743-748. Johnson EC, LM Bohn, LS Barak, RT Birse DR Nassel, MG Caron, and PH Taghert. (2003). Identification of Drosophila neuropeptide receptors by GPCR- b arrestin2 interactions. J. Biol. Chem. 278:52172-52178. Johnson EC, SF Garczynski, D Park, JW Crim, DR Nassel, and PH Taghert. 2003. Identification and characterization of a G protein-coupled receptor for the neuropeptide proctolin in Drosophila melanogaster. Proc. Natl. Acad. Sci. USA 100:6198-6203 Johnson E, T Sherry, J Ringo, and H Dowse. 2002. Modulation of the cardiac pacemaker of Drosophila: Cellular mechanisms. J. Comp. Physiol. B. 172:227-236. Johnson E, J Ringo, and H Dowse. 2001. Dynamin, encoded by shibire, is central to cardiac function. J. Exp. Zool. 289:81-89.