JOHNSTON, DANIEL

Daniel Johnston

Professor
Department of Neuroscience

Karl Folkers Chair in Interdisciplinary Biomedical Research

Cellular neurophysiology–information processing and storage in single neurons and small neural networks; memory, epilepsy.

djohnston@mail.clm.utexas.edu

Phone: 512-232-6564

Office Location
NHB 2.504

Postal Address
The University of Texas at Austin
Department of Neuroscience, College of Natural Sciences
1 University Station C7000
Austin, TX 78712

Ph.D., Duke University (1974)

Research Summary:
Research in my laboratory is primarily directed towards understanding the cellular and molecular mechanisms of synaptic integration and long-term plasticity of neurons in the medial temporal lobe. We have focused our attention on the hippocampus, subiculum, and entorhinal cortex, areas of the brain that play important roles in learning and memory. These regions are also of interest because they have a low seizure threshold and are implicated in several forms of human epilepsy. Our research uses quantitative electrophysiological, optical-imaging, and computer-modeling techniques.

We are investigating long-term synaptic potentiation and depression, forms of plasticity thought to underlie aspects of memory. This interest has led us to investigate the basic mechanisms of synaptic integration in the dendrites of the neurons in these regions. We have used fluorescence imaging techniques and dendritic patch-clamp recordings to identify the types of voltage-gated ion channels (Na+, K+, Ca+, and h channels) expressed in dendrites of hippocampal and entorhinal cortex pyramidal neurons.

We have also begun to identify changes in the properties and expression levels of some of these channels accompanying synaptic potentiation and depression. These studies have suggested that plasticity of intrinsic excitability of neurons is an important component of learning and memory. Our computer modeling studies, which reconstruct the biophysical properties of these neurons based on our experimental data, complement this work. We hope that these investigations will enhance our understanding of the neuronal mechanisms of learning and memory and provide insight into the function of the hippocampus and neighboring cortex in the normal behaving animal as well as under disease states such as epilepsy.

2015 Siegel, J.J., Taylor, W., Gray, R., Kalmbach, B., Zemelman, B.V., Desai, N.S., Johnston, D., and Chitwood, R.A. Trace eyeblink conditioning in mice is dependent upon the cerebellum and dorsal medial prefrontal cortex: Behavioral characterization and functional circuitry. eNeuro (DOI: 10.1523/ENEURO.0051-14.2015)

2015 Desai, N.S., Siegel, J.J., Taylor, W., Chitwood, R.A., and Johnston, D. Matlab-based automated patch clamp system for awake behaving mice. J. Neurophysiol. 10.1152/jn.00025.2015

2015 Dembrow, N.C., Zemelman, B.V., and Johnston, D. Temporal dynamics of L5 dendrites in medial prefrontal cortex regulate integration versus coincidence detection of afferent inputs. J. Neurosci. 35: 4501-4514

2015 Kim, C.S. and Johnston, D. A1 adenosine receptor-mediated GIRK channels contributes to the resting conductance of CA1 neurons in the dorsal hippocampus.  J. Neurophysiol. 113:2511-2523

2015 Ashhad, S., Johnston, D., and Narayanan, R. Activation of inositol trisphosphate receptors is sufficient for inducing graded intrinsic plasticity in rat hippocampal pyramidal neurons. J. Neurophysiol. 113:2002-2013

2014 Clemens, A.M. and Johnston, D. Age- and location-dependent differences in store depletion induced h-channel plasticity in hippocampal pyramidal neurons J. Neurophysiol. 111:1368-1382

2014 Moya, M.V., Siegel, J.J., McCord, E.D., Kalmbach, B.E., Dembrow, N., Johnston, and Chitwood, R.A.. Species-specific differences in medial prefrontal projections to the pons between rat and rabbit. J. Comp. Neurol. 13:3052-3074

2014 Edwards, J., Daniel, E., Kinney, J., Bartol, T., Sejnowski, T., Johnston, D., Harris, K.M., and Bajaj, C. VolumeRover: Enhancing surface and volumetric reconstruction for realistic dynamical simulation of cellular and subcellular function. Neuroinformatics 12:277-289

2013 Routh, B., Johnston, D., and Brager, D.H. Loss of functional A-type potassium channels in the dendrites of CA1 pyramidal neurons from a mouse model of Fragile X syndrome. J. Neurosci. 33:19442-19450

2013 Vaidya, S.P. and Johnston, D. Temporal synchrony and gamma to theta power conversion in the dendrites of CA1 pyramidal neurons. Nature Neurosci. 16:1812-1820

2013 Brager, D.H., Lewis, A.S., Chetkovich, D.M., and Johnston, D. Short-term potentiation and heterosynaptic plasticity in CA1 neurons from mice lacking the h-channel auxiliary subunit TRIP8b.  J. Neurophysiol. 110:2350-2357

2013 Kalmbach, B.E., Chitwood, R., Dembrow, N. and Johnston, D. Dendritic generation of mGluR mediated slow afterdepolarization in layer 5 neurons of prefrontal cortex.  J. Neurosci., 33:13518 -13532

2013 Dougherty, K.A., Nicholson, D.A., Diaz, L., Buss, E.W., Neuman, K.M., Chetkovich, D.M., and Johnston, D. Differential expression of HCN1 and HCN2 subunits alters voltage-dependent gating of h-channels in CA1 pyramidal neurons from the dorsal and ventral hippocampus.  J. Neurophysiol.  109:1940-1953

2013 Park, Y.Y, Johnston, D., and Gray, R. Persistent Na+ current mediates neuronal excitability in hippocampal CA1 pyramidal neurons.  J. Neurophysiol. 109:1378-1390

2012 Dougherty, K.A., Islam, T., and Johnston, D. Intrinsic Excitability of CA1 pyramidal neurons from the rat dorsal and ventral hippocampus.  J. Physiol., 509:5707–5722

2012 Kim, C.S., Chang, P.Y., and Johnston, D. Knockdown of HCN1 channels in dorsal hippocampus enhances network activity and leads to anxiolytic- and antidepressant-like effects. Neuron 75:503–516

2012 Brager, D.H., Akhavan, A.R., and Johnston, D., Impaired dendritic expression and plasticity of h-channels in the fmr1-/y mouse model of Fragile X Syndrome, Cell Reports 1: 225-233

2011 Lewis, A.S., Vaidya, S., Blaiss, C.A., Liu, Z., Stroub, T., Brager, D.H., Chen, X., Bender, R.A., Estep, C.M., Popov, A.B., Kang, C., Van Veldhoven, P.P., Bayliss, D.A., Nicholson, D.A., Powell, C.M., Johnston, D., and Chetkovich, D.M., Deletion of the HCN channel auxiliary subunit TRIP8b impairs hippocampal Ih localization and function and promotes antidepressant behavior in mice., J. Neurosci. 31: 7424-7440

2010 Dembrow, N.C., Chitwood, R.A., and Johnston, D., Projection-specific neuromodulation of medial prefrontal cortex neurons., J. Neurosci. 30: 16922-16937

2010 Narayanan, R. Dougherty, K., and Johnston, D., Calcium store depletion induces persistent perisomatic increases in the functional density of h channels in hippocampal pyramidal neurons., Neuron 68: 921-935

2010 Narayanan, R. and Johnston, D., The h current is a candidate mechanism for regulating the sliding modification threshold in a BCM-like synaptic learning rule., J. Neurophysiol. 104: 1020-1033

2009 Routh, B. Johnston, D., Harris, K.M., and Chitwood, R., Anatomical and electrophysiological comparison of CA1 pyramidal neurons of the rat and mouse., J. Neurophysiol. 102: 2288-2302

2008 Shin M, Brager DH, Jaramillo TC, Johnston D, Chetkovich DM., Mislocalization of h channel subunits underlies h channelopathy in temporal lobe epilepsy, Neurobiol. Dis. 32: 26-36

2008 Narayanan R, Johnston D., The ascent of channels with memory, Neuron 60: 735-738

2008 Johnston D, Narayanan R., Active dendrites: colorful wings of the mysterious butterflies., Trends Neurosci. 31: 309-16

2008 Narayanan R, Johnston D., The h channel mediates location dependence and plasticity of intrinsic phase response in rat hippocampal neurons., J. Neurosci. 28: 5846-60

2007 Narayanan R, Johnston D., Long-term potentiation in rat hippocampal neurons is accompanied by spatially, Neuron 56: 1061-75

2007 Brager DH, Johnston D., Plasticity of intrinsic excitability during long-term depression is mediated through mGluR-dependent changes in I(h) in hippocampal CA1 pyramidal neurons., J. Neurosci. 27: 13926-37

2007 Rosenkranz, J.A. and Johnston, D., State-dependent modulation of amygdala inputs by dopamine-induced enhancement of sodium currents in Layer V entorhinal cortex., J. Neurosci. 27: 7054-7069

2007 Gasparini, S., Losonczy, A., Chen, X., Johnston, D., and Magee, J.C., Associative pairing enhances action potential back-propagation in radial oblique branches of CA1 pyramidal neurons., J. Physiology 580: 787-800

2006 Chen, X. and Johnston, D, Voltage-gated ion channels in dendrites of hippocampal neurons., Pflugers Arch 453: 397-401

2006 Chen, X., Yuan, L.-L., Zhao, C., Birnbaum, S.G., Frick, A., Jung, W.E., Schwarz, T.L., Sweatt, J.D., and Johnston, D., Deletion of Kv4.2 gene eliminates dendritic A-type K+ current and enhances induction of long-term potentiation in hippocampal CA1 pyramidal neurons., J. Neurosci 26: 12143-12151

2006 Yuan, LL, Chen, X, Kunjilwar, K. Pfaffinger, P, and Johnston, D., Acceleration of K+ channel inactivation by the MEK inhibitor U0126. , Amer. J. Physiol. 290: C165-C171

2006 Rosenkranz, J.A. and Johnston, D., Voltage-dependent dopaminergic regulation of neuronal excitability through modulation of Ih in layer V entorhinal cortex, J. Neuroscience 26: 3229-3244

2005 Frick, A. and Johnston, D., Plasticity of dendritic excitability, J. Neurobiol 64: 100-115

2005 Fan, Y, Fricker, D., Brager, D., Chen, X, Lu, H.C, Chitwood, R, and Johnston, D., Activity-dependent decrease of excitability in hippocampal neurons through increases in Ih, Nature Neuroscience 8: 1542-1551

2005 Koester, H.J. and Johnston, D., Target-Cell Dependent Normalization of Transmitter Release at Neocortical Synapses., Science 308: 863-866

2004 Frick, A., Magee, and Johnston, D, LTP is accompanied by an enhanced local excitability of pyramidal neuron dendrites., Nature Neuroscience 7: 126-135

 

  • 1970 Graduate with Distinction, School of Engineering, University of Virginia
  • 1969-1974 Research Assistantship, Duke University
  • 1976 Grass Foundation Fellowship in Neurobiology
  • 1982-1985 McKnight Foundation Neurosci. Develop. Award
  • 1980-Present Editorial Boards J. Neuroscience (1997-) J. Neurophysiology (1986-) Neuroscience (2000-) Cellular and Molecular Neurobiol. (1980-1994) Epilepsy Research (1986-1998)
  • 1975-Present Reviewer for numerous scientific journals, including Science, Nature, PNAS, Neuron, J. Neurosci., and J. Physiol.
  • 1980-Present Ad Hoc member of study sections for NIH and ADAMHA and outside grant reviewer for NSF and VA.
  • Regular member of NIMH BPN-2 Study Section (1984-1988)
  • Regular member of NIMH MHSP-N Study Section (1992-1994)
  • Regular member of IFCN-7 Study Section (2000-)
  • 1989-Present MERIT Award, NIMH
  • 1997 Michael E. DeBakey, M.D., Excellence in Research Award, Baylor College of Medicine
  • 1999 Marc Dresden Excellence in Graduate Education Award Baylor College of Medicine
  • 2001 Barbara and Corbin J. Robertson, Jr. Presidential Award for Excellence in Education
  • 1998-2002 Co-Chair and Chair, Gordon Conference on Synaptic Transmission
  • 2009 Gill Center Distinguished Neuroscience Investigator Award
  • 2011 McKnight Foundation Memory and Cognitive Disorders Award