GTPase activity associates with the inhibitory GTP‐binding regulatory component of adenylate cyclase purified from rat brain

FEBS Letters

Asakawa, Takeo¹  Enomoto, Keiichi¹ 

[1] Department of Pharmacology, Saga Medical School, Saga 840-01, Japan

关键词: GTPase;    Inhibitory regulatory component (Ni);    Adenylate cyclase;    Islet-activating protein;    ADP-ribosylation;    Rat brain;    IAP;    islet-activating protein;    Ns and Ni;    the stimulative and inhibitory GTP-binding regulatory components of adenylate cyclase;    respectively;    Gpp(NH)p;    5'-guanylyl imidodiphosphate;   

DOI  :  10.1016/0014-5793(84)80494-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The inhibitory regulatory component of adenylate cyclase (N_i) was highly purified from rat brain synaptic membranes. A low K _m GTPase activity was always associated with N_i through the purification, and the recovery of GTPase activity correlated well with that of N_i. Purified N_i was hardly ADP-ribosylated by islet-activating protein (IAP). A heat-labile factor in the fraction of the stimulative regulatory component (N_s) restored ADP-ribosylation and also activated the GTPase about 2-fold. NaF which was reported to interact with N_i markedly reduced GTPase activity. The purified N_i fraction inhibited adenylate cyclase only in the presence of a heat-stable factor found in the partially purified regulatory component. GTPase and inhibitory activities were weak in myelin which contained only a small amount of N_i. These findings support the view that GTPase activity is an intrinsic activity of N_i and some factors are necessary for the function of N_i.

【 授权许可】

Unknown