KCNK9 Protein — Potassium Two Pore Domain Channel Subfamily K Member 9 is a protein that kcnk9/task-3 channels serve several essential functions in [neurons](/entities/neurons)[@channels2007][@task2010]:. This page describes its structure, normal nervous system function, role in neurodegenerative disease, and potential as a therapeutic target.
KCNK9 Protein — Potassium Two Pore Domain Channel Subfamily K Member 9 is a protein that kcnk9/task-3 channels serve several essential functions in [neurons](/entities/neurons)[@channels2007][@task2010]:. This page describes its structure, normal nervous system function, role in neurodegenerative disease, and potential as a therapeutic target.
KCNK9 (Potassium Two Pore Domain Channel Subfamily K Member 9), also known as TASK-3, is a member of the two-pore domain (K2P) potassium channel family. KCNK9 is highly expressed in the brain, particularly in regions involved in respiratory control, arousal, and mood regulation. The channel contributes to the background potassium conductance that sets the resting membrane potential and modulates neuronal firing properties[@task2001][@task2005].
Protein Overview
KCNK9 forms leak potassium channels that provide background conductance in neurons. These channels are critical for maintaining neuronal resting membrane potential and regulating excitability.
Normal Function
KCNK9/TASK-3 channels serve several essential functions in neurons[@channels2007][@task2010]:
Background Potassium Conductance
Provides steady-state potassium leak current
Sets resting membrane potential near K+ equilibrium potential
Stabilizes neuronal membrane at ~-70mV
Prevents excessive neuronal excitation
Neuronal Excitability Regulation
TASK-3 modulates neuronal firing properties by:
Controlling action potential threshold
Regulating firing frequency
Modulating after-hyperpolarization
Affecting firing patterns
Brain Region-Specific Roles
KCNK9 is enriched in:
Thalamus: Sensory processing, arousal
[Cortex](/brain-regions/cortex): Cortical excitability, pyramidal neuron function