The long-term goals of this project are to develop an understanding of the fundamental mechanisms that control the function of K2P (KCNK) potassium channels and to develop methods to identify and characterize small molecule, ion channel modulators for the K2P family. K2Ps are a diverse family of potassium-selective channels that are responsible for background 'leak'currents. These currents are pivotal in modulating the excitability of neurons. K2Ps respond to varied stimuli that include pH changes, temperature, and mechanical force. Although, K2Ps have well-established roles in the nervous and cardiovascular systems and are implicated in pain, anesthetic responses, thermosensation, and mood, they are the least well-understood potassium channel class. Ion channels are coveted drug targets. As membrane proteins, they are readily accessible to extracellular compounds and their modulation brings about rapid changes in the properties of excitable cells in the heart and brain. However, as membrane proteins, they also reside beyond many of the well-established approaches for modulator development that require purified material. Consequently, many channels, including those in the K2P family, lack significant pharmacologies. This problem leads to a gap in our ability to connect ion channel genes with in vivo function. We are pursuing a multidisciplinary approach that includes genetic selections, biophysical, and electrophysiological measurements to identify, dissect, and characterize the core elements that control K2P function and to define and characterize new small molecules that control K2P activity. Defining the molecular mechanisms that control K2p activity and uncovering new K2P modulators should provide the key framework and necessary tools for understanding how K2Ps function. Because of their important roles in human physiology, K2Ps are targets for drugs for the treatment of chronic pain, stroke, and depression. Thus, developing an understanding of how K2Ps function and means to find and small molecules that affect channel function should not only provide powerful tools for dissecting K2P mechanism but should aid in the development of new therapeutic agents for a range of human diseases.

Public Health Relevance

Ion channels are the targets of drugs used to treat pain, epilepsy, mood disorders, hypertension, and arrhythmia. Our work aims to understand the fundamental mechanisms that control the function of a family of ion channels, known as K2Ps, that are involved in thermal, mechanical, and chemical sensing and to develop novel reagents that affect channel function. Such knowledge and reagents have direct relevance for development of more efficacious treatments of nervous system and cardiovascular disorders.

Agency
National Institute of Health (NIH)
Institute
National Institute of Mental Health (NIMH)
Type
Research Project (R01)
Project #
5R01MH093603-04
Application #
8611969
Study Section
Biophysics of Neural Systems Study Section (BPNS)
Program Officer
Nadler, Laurie S
Project Start
2011-03-01
Project End
2016-02-29
Budget Start
2014-03-20
Budget End
2015-02-28
Support Year
4
Fiscal Year
2014
Total Cost
$386,250
Indirect Cost
$136,250
Name
University of California San Francisco
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
094878337
City
San Francisco
State
CA
Country
United States
Zip Code
94143
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