Evidence for a Ca2+‐independent hydrolysis of phosphatidylinositol 4,5‐bisphosphate in neuron‐like cell line NG108‐15 cells

FEBS Letters

Yano, Koh¹  Nozawa, Yoshinori¹  Higashida, Haruhiro² 

[1] Department of Biochemistry, Gifu University School of Medicine, Tsukasamachi-40, Gifu 500, Japan;Department of Pharmacology, Cancer Research Institute, Kanazawa University, 13-1 Takaramachi, Kanazawa 920, Japan

关键词: Neuroblastoma × glioma;    Bradykinin;    Potassium depolarization;    Phosphoinositide;    Calcium;    PI-4.5-P2;    phosphatidylinositol 4;    5-bisphosphate;    TBS;    Tris-buffered saline;   

DOI  :  10.1016/0014-5793(85)80784-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The addition of bradykinin to ³²P_i-labeled neuroblastoma × glioma hybrid NG108-15 cells caused a substantial loss of radioactivity from phosphatidylinositol 4,5-bisphosphate (PI-4,5-P₂). The bradykinin-induced hydrolysis of PI-4,5-P₂ was almost equally observed even when extracellular Ca²⁺ was depleted with EGTA (100μM). On the other hand, high K⁺ depolarization of the cells, which allows Ca²⁺ influx through voltage-dependent Ca²⁺ channels, failed to induce any significant decrease in the radioactivity of PI-4,5-P₂. These data indicate that the bradykinin-stimulated PI-4,5-P₂ hydrolysis in NG108-15 cells is independent of extracellular Ca²⁺ and also that PI-4,5-P₂ hydrolysis is not stimulated by an elevation of intracellular Ca²⁺ concentration.

【 授权许可】

Unknown