Abolition of G protein inhibition of α 1A and α 1B calcium channels by co‐expression of the β 3 subunit

FEBS Letters

Treistman, Steven N.¹  Anantharam, Vellareddy¹  Roche, John P.¹ 

[1] Department of Pharmacology and Program in Neuroscience, University of Massachusetts Medical School, 55 Lake Ave North, Worcester, MA 01655, USA

关键词: Calcium channel;    G protein;    α 1A subunit;    α 1B subunit;    α 1C subunit;    β 3 subunit;    BAPTA;    K3-1;    2-bis(aminophenoxy)ethane-N;    N;    N′;    N′-tetracetic acid;    NEM;    n-ethylmaleimide;    GDPβS;    guanosine-5′-o-(2-thiodiphosphate);    DHP;    1;    4-dihydropyridine;   

DOI  :  10.1016/0014-5793(95)00860-C

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Three different classes of α ₁ Ca²⁺ channel (α _1A, α _1B, α _1C) were expressed in Xenopus oocytes to determine whether G protein-mediated inhibition is an inherent property of the α ₁, subunit itself, and if so, whether co-expression of auxiliary subunits modulates the inhibition seen. From our data it is apparent that either α _1A or α _1B Ca²⁺ channels expressed alone are sufficient for voltage-dependent G protein inhibition. α _1C Ca²⁺ channels expressed alone do not exhibit the G protein inhibition seen in α _1A and α _1B channels. Additionally, co-expression of the β ₃ subunit abolishes the ability of G proteins to inhibit currents through α _1A and α _1B Ca²⁺ channels. Differential sensitivity of α ₁ as well as modulation of properties by β ₃ provide a potential mechanism for the regulation of G protein-mediated inhibition in neurons.

【 授权许可】

Unknown