Susan Tsunoda, PhD
Our research focuses on the localization, regulation, and function of voltage-gated K+ channels. Shal (Kv4) K+ channels are the most highly conserved of the voltage-gated K+ channels, in sequence, function, as well as subcellular localization. Across species, Shal K+ channel genes share more than 80% sequence identity, encode transient A-type K+ currents, and display a somato-dendritic distribution in neurons. We use Drosophila melanogaster as a model to study: how Shal K+ channels are targeted to somato-dendritic domains and excluded from axons, how their biophysical properties are regulated by other proteins, how their expression is regulated by activity, and what role Shal K+ channels play in excitability, synaptic function and integration. We combine a variety of approaches, including electrophysiology, imaging, Drosophila genetics, and molecular and cell biological techniques, to answer questions more difficult to address in mammals.
Lieu M-H, Vallejos MJ, Michael E, Tsunoda S. 2012. Mechanisms underlying stage-1 TRPL translocation in Drosophila photoreceptors. PLoS One, In press.
Ping Y, Tsunoda S. 2012. Inactivity-induced increase in nAChRs up-regulates Shal K+ channels to stabilize synaptic potentials. Nature Neurosci 15:90-97.
Ping Y, Waro G, Licursi A, Smith S, Vo-Ba D, Tsunoda S. 2011. Shal/Kv4 channels are required for maintaining excitability during repetitive firing and normal locomotion and grooming in Drosophila. PLoS One 6(1):e16043.
Diao F, Chaufty J, Waro G, Tsunoda S. 2010. SIDL interacts with the dendritic localization motif of Shal (Kv4) K+ channels in Drosophila. Molec Cell Neurosci 45(1):75-83.
Diao F, Waro G, Tsunoda S. 2009. Fast inactivation of Shal (Kv4) K+ channels in Drosophila neurons is regulated by the novel interactor SKIP3. Molec Cell Neurosci 42:33-44.
Sanxaridis P, Cronin MA, Rawat SS, Waro G, Acharya U, Tsunoda S. 2007. Light-induced recruitment of INAD-signaling complexes to detergent-resistant lipid rafts in Drosophila photoreceptors. Molec Cell Neurosci 36:36-46.
Cronin MA, Lieu M-H, Tsunoda S. 2006. Two stage of light-dependent TRPL-channel translocation in Drosophila photoreceptors. J Cell Sci 119:2935-2944.
Cronin MA, Diao F, Tsunoda S. 2004. Light-dependent subcellular translocation of Gqa in Drosophila photoreceptors is facilitated by the photoreceptor-specific myosin III, NINAC. J Cell Sci 117:4797-4806.
Tsunoda S, Sun Y, Suzuji E, Zuker CS. 2001. Independent anchoring and assembly mechanisms of INAD signaling complexes in Drosophila photoreceptors. J Neurosci 21:150-158.
Tsunoda S, Sierralta J, Sun Y, Bodner R, Suzuki E, Becker A, Socolich M, Zuker CS. 1997. A multivalent PDZ-domain protein assembles signalling complexes in a G-protein-coupled cascade. Nature 388:243-249.
Tsunoda S, Salkoff L. 1995. The major delayed rectifier in both Drosophila neurons and muscle is encoded by Shab. J Neurosci 15:5209-5221.
Tsunoda S, Salkoff L. 1995. Genetic analysis of Drosophila neurons: Shal, Shaw, and Shab encode most embryonic potassium currents. J. Neurosci 15:1741-1754.
Butler A, Tsunoda S, McCobb D, Wei A, Salkoff L. 1993. mSlo, a complex mouse gene encoding "Maxi" calcium-activated potassium channels. Science 261:221-224.