KV4.3 | Shal Related Potassium Channel Member 3
Shaker (KV1.1–KV1.8), Shab (KV2.1-KV2.2), Shaw (KV3.1–KV3.4), Shal (KV4.1–KV4.3), KQT like (KV7.1–KV7.5), Eag related (KV10.1-KV10.2), Erg related (KV11.1–KV11.3), Elk related (KV12.1)
Contains six transmembrane domains (S1–S6), four single subunits form a pore, homotetramers and heterotetramers are possible.
KV4.3 Background Information
KV4.3, a voltage-activated A-type potassium ion channel, is prominent in the repolarization phase of the action potential and contributes to the cardiac transient outward potassium current (Ito1), the main contributing current to the repolarizing phase 1 of the cardiac action potential. Furthermore it contributes to ISA currents in neurons.
UniProt Q9UK17-1, Q9UK17-2 (two different isoforms encoded by alternatively spliced transcript variants of the gene)
repolarization of action potentials
Brugada Syndrome 9 (gain of function mutation), Spinocerebellar Ataxia 19, autosomal dominant inheritance, cerebellar atrophy, cognitive impairment, cogwheel rigidity, dysarthria
Homotetramer or heterotetramer with KCND1 and/or KCND2. Associates with the regulatory subunits KCNIP1, KCNIP2, KCNIP3 and KCNIP4, KCNE1, KCNE2, SCN1B, SRC, KCNAB1 and DLG1
4-AP, imipramine, E-4031, amitriptyline, disopyramide, XE 991 dihydrochloride
Patch Clamp: whole cell
Gutman et al. (2005) International Union of Pharmacology. LIII. Nomenclature and molecular relationships of voltage-gated potassium channels. Pharmacol Rev 57(4):473-508