KCNA3
Domain
The N-terminus may be important in determining the rate of inactivation of the channel while the tail may play a role in modulation of channel activity and/or targeting of the channel to specific subcellular compartments.
The segment S4 is probably the voltage-sensor and is characterized by a series of positively charged amino acids at every third position.
Function
Isoform 1
Mediates the voltage-dependent potassium ion permeability of excitable membranes. Assuming opened or closed conformations in response to the voltage difference across the membrane, the protein forms a potassium-selective channel through which potassium ions may pass in accordance with their electrochemical gradient.
Isoform 2
Mediates the voltage-dependent potassium ion permeability of excitable membranes. Assuming opened or closed conformations in response to the voltage difference across the membrane, the protein forms a potassium-selective channel through which potassium ions may pass in accordance with their electrochemical gradient.
Isoform 3
Lacks voltage-gated potassium channel activity.
Post-translational modifications
N-glycosylation promotes the cell surface expression.
Phosphorylation on Tyr-499 inhibits its channel activity.
Sequence Similarities
Belongs to the potassium channel family. A (Shaker) (TC 1.A.1.2) subfamily. Kv1.3/KCNA3 sub-subfamily.
Cellular localization
- Isoform 1
- Cell membrane
- Multi-pass membrane protein
- Isoform 2
- Cell membrane
- Multi-pass membrane protein
- Isoform 3
- Cytoplasm
- Perinuclear region
Alternative names
HGK5, KCNA3, Potassium voltage-gated channel subfamily A member 3, HLK3, HPCN3, Voltage-gated K(+) channel HuKIII, Voltage-gated potassium channel subunit Kv1.3