Effects of phosphorylation of inhibitory GTP‐binding protein by cyclic AMP‐dependent protein kinase on its ADP‐ribosylation by pertussis toxin, islet‐activating protein

FEBS Letters

Iwakura, Katsuomi¹  Watanabe, Yasuhiro¹  Misaki, Naoyuki¹  Imaizumi, Taro¹  Yoshida, Hiroshi¹ 

[1] Department of Pharmacology I, Osaka Univerity, School of Medicine, Osaka 530, Japan

关键词: ADP-ribosylation;    Islet-activating protein;    cyclic AMP-dependent protein kinase;    Phosphorylation;    GTP-binding protein;    db-cAMP;    dibutyryl cyclic AMP;    GTPγS;    guanosine 5′-(3-O-thio)triphosphate;   

DOI  :  10.1016/0014-5793(88)80058-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Pretreatment of rat cardiac myocytes with the β-adrenergic agonist, db-cAMP or forskolin decreased ADP-ribosylation of 40–41 kDa protein by islet-activating protein (IAP) in cell membranes. Addition of activated cyclic AMP-dependent protein kinase (protein kinase A) catalytic subunit and MgCl₂ also decreased ADP-ribosylation of 40–41 kDa protein by IAP in cell membranes. The α- and β-subunits of partially purified inhibitory GTP-binding protein (G_i) were both phosphorylated by protein kinase A. The amounts of phosphate incorporated into the subunits of G_i were 0.34 and 0.18 mol/mol protein. These show that phosphorylation of G_i by protein kinase A results in a decrease in its ADP-ribosylation by IAP.

【 授权许可】

Unknown