Two distinct populations of ARF bound to Golgi membranes
Two distinct populations of ARF bound to Golgi membranes
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与高尔基体膜结合的两个不同的 ARF 群体
DOI：
--
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发表时间：
1993
影响因子：
7.8
通讯作者：
J. E. Rothman
中科院分区：
文献类型：
--
作者：
J. Helms;David J. Palmer;J. E. Rothman
ADP-核糖基化因子（ARF）是一种小分子量的GTP结合蛋白（20 kD），参与囊泡蛋白的转运。与ARF蛋白结合的鸟嘌呤核苷酸被认为可调节ARF的活性，但其作用机制仍不清楚。我们以前曾报道，ARF结合高尔基体膜后，Brefeldin A敏感的核苷酸交换的ARF结合的GDP GTP γ S。在这里，我们报告，治疗与磷脂酰胆碱脂质体有效地去除40-60%的ARF结合高尔基膜与非水解GTP，大概是通过竞争结合的激活ARF的脂质双层。这揭示了高尔基体膜上存在两种不同的ARF池。而总的ARF结合似乎没有饱和，脂质体抗性池是饱和的，这表明该池的ARF是稳定的高尔基体膜组件的相互作用。我们建议，ARF的鸟嘌呤核苷酸交换蛋白的激活结果在协会的豆蔻酰化ARF GTP与高尔基体的脂质双层。一旦与膜结合，活化的ARF可以自由扩散以稳定地与靶蛋白结合，或者可能被GTP酶活化蛋白（GAP）活性灭活。
ADP-ribosylation factor (ARF) is a small molecular weight GTP-binding protein (20 kD) and has been implicated in vesicular protein transport. The guanine nucleotide, bound to ARF protein is believed to modulate the activity of ARF but the mechanism of action remains elusive. We have previously reported that ARF binds to Golgi membranes after Brefeldin A-sensitive nucleotide exchange of ARF-bound GDP for GTP gamma S. Here we report that treatment with phosphatidylcholine liposomes effectively removed 40-60% of ARF bound to Golgi membranes with nonhydrolyzable GTP, presumably by competing for binding of activated ARF to lipid bilayers. This revealed the presence of two different pools of ARF on Golgi membranes. Whereas total ARF binding did not appear to be saturable, the liposome-resistant pool is saturable suggesting that this pool of ARF is stabilized by interaction with a Golgi membrane-component. We propose that activation of ARF by a guanine nucleotide-exchange protein results in association of myristoylated ARF GTP with the lipid bilayer of the Golgi apparatus. Once associated with the membrane, activated ARF can diffuse freely to associate stably with a target protein or possibly can be inactivated by a GTPase activating protein (GAP) activity.
腺苷酸环化酶调节成分的鸟嘌呤核苷酸激活位点。
DOI：
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发表时间：
1982
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Northup,JK;Smigel,MD;Gilman,AG
通讯作者：
Gilman,AG
纯化囊泡运输所需的三种相关外周膜蛋白。
DOI：
--
发表时间：
1990
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Clary,DO;Rothman,JE
通讯作者：
Rothman,JE
ADP-核糖基化因子是内质网和顺式高尔基体之间的囊泡运输所必需的。
DOI：
--
发表时间：
1992
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Balch,WE;Kahn,RA;Schwaninger,R
通讯作者：
Schwaninger,R