Faculty Profile
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John A. Payne
Professor Physiology and Membrane Biology 4112A Tupper Hall Office (530) 752-3336 Lab japayne@ucdavis.edu http://www.physiology.ucdavis.edu/payne/index.html |
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| Ion and water homeostasis of excitable cells | |
Degrees:
1991 - PhD - University of Florida - Zoology
1987 - MS - Duke University - Physiology
1983 - BA - University of California, Berkeley - Biology (marine emphasis)
Awards:
Membership, Honor Society of Phi Kappa Phi
Established Investigator, American Heart Association
Department and Center Affiliations:
Center for Neuroscience
Professional Societies:
American Physiological Society
Society for Neuroscience
Biophysical Society
Red Cell Club
Grad Group Affiliations and Specialties:
Biochemistry and Molecular Biology
Molecular, Cellular, and Integrative Physiology
Non-DBS Grad Group(s) - Pharmacology and Toxicology
Publications:
Payne, J.A. The potassium-chloride cotransporters: from cloning to structure and function. In Physiology and Pathology of Chloride Transporters and Channels in the Nervous System: From Molecules to Diseases. (Ed. F.J. Alvarez-Leefmans and E. Delpire). Elsevier, 2009.
Chung, C.-Y. and J.A. Payne. Modulaton of GABAergic signaling: role of neuronal chloride. In Encyclopedia of Basic Epilepsy Research, (Ed. P.A. Schwartzkroin). Elsevier, 2009.
Lee, H.H.C., J.A. Walker, J.R. Williams, R.J. Goodier, J.A. Payne, and S.J. Moss. Direct PKC-dependent phosphorylation regulates the cell surface stability and activity of the potassium chloride cotransporter, KCC2. J. Biol. Chem. 282: 29777-29784, 2007.
Williams, J.R. and J.A. Payne. Cation transport by the neuronal K-Cl cotransporter, KCC2: Thermodynamics and kinetics of alternate transport modes. Am. J. Physiol. Cell Physiol. 287: C919-C931, 2004.
Payne, J.A., C. Rivera, J. Voipio, and K. Kaila. Cation chloride cotransporters and their role in neuronal communication, development, and trauma. Trends in Neurosci. 26(4): 199-206, 2003.
Gulyas, A.I., A. Sik, J.A. Payne, K. Kaila, and T.F. Freund. High expression of the K-Cl cotransporter, KCC2, in postsynaptic membranes associated with excitatory inputs of the rat hippocampus emphasizes a dual role in ion and water homeostasis. Eur. J. Neurosci. 13: 2205-2217, 2001.
Williams, J.R., J.W. Sharp, V.G. Kumari, M. Wilson, and J.A. Payne. The neuron-specific K-Cl cotransporter, KCC2: antibody development and initial characterization of the protein. J. Biol. Chem. 274(18): 12656-12664, 1999.
Rivera, C., J. Voipio, J.A. Payne, E. Ruusuvuori, H. Lahtinen, K. Lamsa, U. Pirvola, M. Saarma, K. Kaila. The K+/Cl- co-transporter KCC2 renders GABA hyperpolarizing during neuronal maturation. Nature 397: 251-255, 1999.
Payne, J.A. Functional characterization of the neuronal-specific K-Cl cotransporter: implications for [K+]o regulation. Am. J. Physiol. (Cell Physiol. 42) 273: C1516-C1525, 1997.
Research Interests:
My laboratory examines the cellular physiology of the cation chloride cotransport proteins, including the Na-K-Cl cotransporter (NKCC) and K-Cl cotransporter (KCC). We are particularly interested in the function of these transport proteins in excitable cells, i.e, neurons and muscle cells. We have identified a neuron-specific isoform of the K-Cl cotransporter (KCC2) that is important in maintaining low intracellular [Cl-] for the proper function of ligand-gated anion channels (GABA-A and glycine receptors) in postsynaptic inhibition of mature neurons. Moreover, this novel neuronal KCC may have an important role in the regulation of external [K+] in the brain. The regulation of the cation chloride cotransporters is an important area of our research. Both NKCC and KCC2 appear to have significant roles in regulating intracellular [Cl-] and cell volume of neurons. How are changes in these cell parameters linked to alteration in the kinetic activity of the cotransporters? In the life of a neuron intracellular [Cl-] undergoes dynamic changes, such as during neuronal development or following tramatic insults. These changes in intracellular [Cl-] will lead to alterations in GABAAergic transmission. Are changes NKCC and KCC2 transport activity linked to these events and if so how? We are studying the regulation of NKCC and KCC2 by examining changes in both their kinetic activity and surface protein expression. In addition to their function at the cell level, I am interested in the structure of these proteins and how they function at the molecular level. How do the cotransporters interact with the ions they transport and the inhibitors they bind? Where are these sites of interaction within the protein? How do the cotransporters interact with other regulatory proteins? My laboratory uses whole animal, cellular, and molecular experimentation to answer many of these questions.
Courses Taught:
MCP 210B Advanced Physiology - Term(s): Winter
HPH 400 Medical Physiology - Term(s): Fall