Regulation of the cloned L‐type cardiac calcium channel by cyclic‐AMP‐dependent protein kinase

FEBS Letters

Perez-Reyes, Edward¹  Yuan, Weilong¹  Wei, Xiangyang¹  Bers, Donald M.¹ 

[1] Department of Physiology, Loyola University Medical Center, Maywood, IL 60153, USA

关键词: Calcium channel;    Recombinant DNA;    Clone cell;    Adenosine cyclic monophosphate;    Protein kinase;    Phosphoprotein phosphatase;   

DOI  :  10.1016/0014-5793(94)80484-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Hormones can regulate cardiac L-type Ca²⁺ channels via cAMP-dependent protein kinase (PKA) phosphorylation. However, regulation of the cloned L-type Ca²⁺ channel has been difficult to demonstrate conclusively. We stably transfected a human embryonic kidney (HEK-293) cell with the cardiac α₁ andβ₂ subunits, then examined PKA modulation of the α²⁺ current. Although forskolin did not increase basal Ca²⁺ current, the PKA inhibitors, H-89 and Rp-cAMPS, could inhibit basal current. We reversed H-89 inhibition with either forskolin or okadaic acid. We conclude that the channel was phosphorylated under basal conditions, and that inhibition of PKA allowed dephosphorylation. These studies demonstrate that reversible PKA regulation of cloned Ca²⁺ channels can be studied in HEK-293 cells.

【 授权许可】

Unknown