Modulation of Kv4.3 current by accessory subunits

FEBS Letters

Tomaselli, Gordon F¹  Deschênes, Isabelle¹ 

[1] Department of Medicine, Institute of Molecular Cardiobiology, Division of Cardiology, Johns Hopkins University, 720 N Rutland Avenue, Ross 844, Baltimore, MD 21205, USA

关键词: Ion channel;    Potassium;    Accessory subunit;    I to;    transient outward potassium current;    KChAP;    K channel interacting protein;    KChIP;    Kv channel interacting protein;    MiRP;    minK related protein;    HERG;    human ether-a-go-go related gene;   

DOI  :  10.1016/S0014-5793(02)03296-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Kv4.3 encodes the pore-forming subunit of the cardiac transient outward potassium current (I _to). hKv4.3-encoded current does not fully replicate cardiac I _to, suggesting a functionally significant role for accessory subunits. KChIP2 associates with Kv4.3 and modifies hKv4.3-encoded currents but does not replicate native I _to. We examined the effect of several ancillary subunits expressed in the heart on hKv4.3-encoded currents. Remarkably, the ancillary subunits Kvβ₃, minK, MiRP-1, the Na channel β₁ and KChIP2 increased the density and modified the gating of hKv4.3 current. hKv4.3 promiscuously assembles with ancillary subunits in vitro, functionally modifying the encoded currents; however, the physiological significance is uncertain.

【 授权许可】

Unknown