G protein‐activated K+ channels: a reporter for rapid activation of G proteins by lysophosphatidic acid in Xenopus oocytes

FEBS Letters

Dascal, Nathan¹  Itzhaki Van-Ham, Irit¹  Peleg, Sagit¹  Shapira, Hagit¹  Oron, Yoram¹ 

[1] Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv 69978, Israel

关键词: Rapid desensitization;    G protein-activated potassium channel;    Lysophosphatidic acid receptor;    Go/i protein;    ASODN;    antisense oligodeoxynucleotide;    LPA;    lysophosphatidic acid;    GIRK;    G protein-activated K+ channel;    TRH;    thyrotropin-releasing hormone;    PTX;    pertussis toxin;    GPCR;    G protein-coupled receptor;    PCR;    polymerase chain reaction;   

DOI  :  10.1016/S0014-5793(04)00334-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Threshold concentrations of lysophosphatidic acid (LPA) or acetylcholine (ACh) induce pertussis toxin (PTX)-sensitive rapid desensitization of responses to LPA in Xenopus oocytes. To demonstrate that threshold [LPA] rapidly activates Gi/o proteins, we used the G protein-activated K⁺ channel (GIRK) as a reporter. Low [LPA] induced I _K ⁺ in <3 s of the agonist addition with little or no activation of chloride current. Depletion of Gαo/Gαo1 each decreased the LPA-induced I _K ⁺ by approximately 40–50%, while PTX completely abolished it. This is the first direct evidence showing the activation of GIRK by LPA, and the involvement of G proteins of the Go family in rapid desensitization of LPA responses.

【 授权许可】

Unknown