Molecular Neurophysiology Unit - Division of Intramural Research

 Miguel   Holmgren  Ph.D., Investigator

Dr. Holmgren received his B.S in 1985 from Universidad Autonoma Metropolitana, Unidad Xochimilco, Ciudad de Mexico. In 1994 he received his Ph.D. in Physiology and Biophysics from Finch University of Health Sciences within the Chicago Medical School, working on the sodium/potassium ATPase with Robert Rakowski. Dr. Holmgren went on to do postdoctoral training with Gary Yellen at Harvard Medical School where he studied the gating mechanisms of voltage-activated potassium channels. He joined the NINDS as an Investigator in 2001. Dr. Holmgren's laboratory is exploring the structure and biophysics of various ion channels and transporters.

Laboratory Staff

Jin Chen, Ph.D., Postdoctoral Fellow , 301-451- 6258
Jorge Contreras, Ph.D., Research Fellow , 301-451- 6257
William Lewis, B.S., Predoctoral IRTA Fellow
Angelica Lopez, Ph.D., Visiting Fellow , 301-451- 6258
Deepa Srikumar, M.Sc, Research Assistant , 301-451- 6258

Research Interests

Neurons contain a variety of membrane proteins responsible for the continuous traffic of ions and molecules across the cell membrane. Our main goal is to understand how ions are transported through some of these proteins. We are presently interested in ion channels and the sodium/potassium ATPase; the former moving ions at rates near diffusion, while the latter at rates of about 100 per sec. For both types of proteins, we are asking similar questions. How do ions access their pathway? Which regions of the proteins form the permeation pathways that allow ions to move across the membrane? How does the protein regulate the traffic of ions? What are the interactions of molecules like blockers and toxins with these proteins? We attempt to answer these types of questions by combining molecular biology, chemical modification and electrophysiological techniques.

Selected Recent Publications

Contreras, J.E. Srikumar, D. and Holmgren, M.
Gating at the selectivity filter in cyclic nucleotide-gated channels - PNAS  105 3310-3314 2008

Colina, C., J.J.C. Rosenthal, J.A. DeGiorgis, D. Srikumar, N. Iruku& M. Holmgren
Structural basis of Na+/K+-ATPase adaptation to marine environments - Nature Structural Molecular Biology  14 427-431 2007

Holmgren, M. and Rakowski, RF.
Charge Translocation by the Na+/K+ Pump under Na+/Na+ Exchange Conditions: Intracellular Na+ Dependence - Biophys. J.  90 1607-16 2006

Contreras, JE and Holmgren, M.
Access of quaternary ammonium blockers to the internal pore of cyclic nucleotide-gated channels: implications for the location of the gate. - J. Gen. Physiol.  127 481-94 2006

Bhalla, T., Rosenthal, JJC, Holmgren, M., and Reenan, R.
Control of Human Potassium Channel Inactivation by Editing of a Small mRNA Hairpin - Nature Structural & Molecular Biology  11 950-956 2004

Holmgren, Miguel
Influence of Permeant Ions on Gating in Cyclic Nucleotide-gated Channels - J. Gen Physiol  121 61-72 2003

Selected Earlier Publications

Contact Information

Molecular Neurophysiology Unit, NINDS Porter Neuroscience Research Center  Building 35 Room 3B-1016  35 Convent Drive, MSC 3701 Bethesda MD  20892-3701

Telephone: 301-451- 6259 (office), 301- 451-6258 (laboratory), 301-480- 3943 (fax), Email: holmgren@ninds.nih.gov