ARF1:GTP binds Golgin TRIP11

TRIP11, also known as GMAP210, is a cis-Golgi localized coiled coil Golgin with roles in anterograde and retrograde intra-Golgi trafficking (Infante et al, 1999; Pernet-Gallay et al, 2002). TRIP11 has an N-terminal amphipathic lipid packing sensor (ALPS) domain which binds preferentially to highly curved membranes such as those on veiscles, and a GRIP-related ARF binding (GRAB) domain at its C-terminus that binds to ARF1:GTP. This asymmetric binding allows TRIP11 to tether vesicles to the Golgi membrane. This asymmetric binding of TRIP11 is maintained in part by the fact that ARFGAP1 also contains an ALPS domain and therefore stimulates the GTPase activity of any ARF1:GTP that is present in the vesicular membrane (Drin et al, 2008; Cardenas et al, 2009; Gillingham et al, 2004).

TRIP11，亦称GMAP210，是一种定位于顺式高尔基体的螺旋状Golgin蛋白，其在顺向和逆向高尔基体内运输过程中发挥着重要作用（Infante等，1999；Pernet-Gallay等，2002）。TRIP11蛋白具有一个N端亲水脂质包装传感器（ALPS）结构域，该结构域优先结合于高度弯曲的膜，如囊泡膜，并在其C端含有一个与GRIP相关的ARF结合（GRAB）结构域，该结构域可与ARF1:GTP结合。这种非对称性结合使得TRIP11能够将囊泡锚定于高尔基膜。TRIP11的非对称性结合部分由ARFGAP1也含有ALPS结构域的事实所维持，因为ARFGAP1能够刺激囊泡膜中存在的任何ARF1:GTP的GTP酶活性（Drin等，2008；Cardenas等，2009；Gillingham等，2004）。