This award is issued in response to Notice OD-09-060, Recovery Act Administrative Supplements Providing Summer Research Experiences for Students and Science Educators. DESCRIPTION (provided by applicant): Careful study of genes responsible for rare mendelian forms of human neurological disorders is a powerful approach for gaining insight into the causes, treatment, and potential cure for common, related diseases. The neuronal KCNQ genes were recently discovered as the result of the search for mutant genes causing Benign Familial Neonatal Convulsions, an autosomal dominant epileptic syndrome associated with seizures in infancy and throughout life. Mutations in neuronal KCNQ genes also result in myokymia (a peripheral nerve disorder) and deafness. The KCNQ genes encode subunits of voltage-dependent potassium channels. The long term goals of the proposed work is to understand the in vivo functions of these neuronal KCNQ channels, in order to better understand basic brain signaling mechanisms and to exploit these mechanisms for neurological therapeutics. KCNQ channels regulate neuronal excitability through their intrinsic, voltage-gated activity at particular locations in brain, and through their ability to serve as effectors for neurotransmitter receptors and intracellular signaling pathways. Determining specifically where KCNQ channels are localized in brain circuits, and how receptors, pathways and interacting proteins modulate their activity in the brain, will enhance our ability to exploit these channels as therapeutic targets in conditions involving excessive excitability or alterations and imbalances in modulatory neurotransmission, such as epilepsy and pain syndromes. The current proposal focuses on KCNQ channels on axons in hippocampus, where previous work by the investigator and others indicates KCNQ channels play important roles. It exploits newly available mutant mice with KCNQ2 mutations and phenotypes of increased seizure susceptibility and spontaneous seizures.
The specific aims are to: (1) map the localization of KCNQ subunits in mammalian septohippocampal networks in developing and mature brain of normal and mutant rodents; (2) define the mechanisms targeting KCNQ subunits to axon initial segments and nodes of Ranvier; and (3) analyze the function of axonal KCNQ channels at the subcellular and cellular level.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
3R01NS049119-06S1
Application #
8259255
Study Section
Developmental Brain Disorders Study Section (DBD)
Program Officer
Whittemore, Vicky R
Project Start
2005-04-01
Project End
2011-12-31
Budget Start
2010-07-01
Budget End
2011-12-31
Support Year
6
Fiscal Year
2009
Total Cost
$28,796
Indirect Cost
Name
Baylor College of Medicine
Department
Neurology
Type
Schools of Medicine
DUNS #
051113330
City
Houston
State
TX
Country
United States
Zip Code
77030
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Millichap, John J; Miceli, Francesco; De Maria, Michela et al. (2017) Infantile spasms and encephalopathy without preceding neonatal seizures caused by KCNQ2 R198Q, a gain-of-function variant. Epilepsia 58:e10-e15
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Ho, Tammy Szu-Yu; Zollinger, Daniel R; Chang, Kae-Jiun et al. (2014) A hierarchy of ankyrin-spectrin complexes clusters sodium channels at nodes of Ranvier. Nat Neurosci 17:1664-72
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Battefeld, Arne; Tran, Baouyen T; Gavrilis, Jason et al. (2014) Heteromeric Kv7.2/7.3 channels differentially regulate action potential initiation and conduction in neocortical myelinated axons. J Neurosci 34:3719-32
Chang, Kae-Jiun; Zollinger, Daniel R; Susuki, Keiichiro et al. (2014) Glial ankyrins facilitate paranodal axoglial junction assembly. Nat Neurosci 17:1673-81

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