Arf1 and Membrane Curvature Cooperate to Recruit Arfaptin2 to Liposomes
Arf1 and Membrane Curvature Cooperate to Recruit Arfaptin2 to Liposomes
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DOI：
10.1371/journal.pone.0062963
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发表时间：
2013-04-29
期刊：
影响因子：
3.7
通讯作者：
Goud, Bruno
中科院分区：
文献类型：
--
作者：
Ambroggio, Ernesto E.;Sillibourne, James;Goud, Bruno
Arfaptin2含有Bin/AmphiPhysiin/RVS(BAR)结构域，并在激活的GTP结合状态下与Arf/ARL家族的蛋白质直接相互作用。已有研究表明，杆状结构域能够感知膜的曲率并诱导膜管形成。我们在这里报道，活性Arf1是模拟高尔基体脂质成分的人工脂质体中重新招募Arfaptin2所必需的。Arfaptin2依赖Arf1的募集随膜曲率的增加而增加，而Arf1本身的募集对膜曲率并不敏感。在高蛋白浓度下，Arfaptin2的结合诱导膜微管形成。最后，当ArfGAP1催化Arf1中的GTP水解为GDP时，膜结合的Arfaptin2从脂质体中释放出来。这些结果表明，Arf1的激活和高的膜曲率都是Arfaptin2有效地募集到膜上所必需的。
Arfaptin2 contains a Bin/Amphiphysin/Rvs (BAR) domain and directly interacts with proteins of the Arf/Arl family in their active GTP-bound state. It has been proposed that BAR domains are able to sense membrane curvature and to induce membrane tubulation. We report here that active Arf1 is required for the recruitment of Arfaptin2 to artificial liposomes mimicking the Golgi apparatus lipid composition. The Arf1-dependent recruitment of Arfaptin2 increases with membrane curvature, while the recruitment of Arf1 itself is not sensitive to curvature. At high protein concentrations, the binding of Arfaptin2 induces membrane tubulation. Finally, membrane-bound Arfaptin2 is released from the liposome when ArfGAP1 catalyzes the hydrolysis of GTP to GDP in Arf1. These results show that both Arf1 activation and high membrane curvature are required for efficient recruitment of Arfaptin2 to membranes.