Rein Ulrike, Andag Uwe, Duden Rainer, Schmitt Hans Dieter, Spang Anne
Friedrich Miescher Laboratory, Max Planck Society, D-72076 Tübingen, Germany.
J Cell Biol. 2002 Apr 29;157(3):395-404. doi: 10.1083/jcb.200112092. Epub 2002 Apr 22.
In eukaryotic cells, secretion is achieved by vesicular transport. Fusion of such vesicles with the correct target compartment relies on SNARE proteins on both vesicle (v-SNARE) and the target membranes (t-SNARE). At present it is not clear how v-SNAREs are incorporated into transport vesicles. Here, we show that binding of ADP-ribosylation factor (ARF)-GTPase-activating protein (GAP) to ER-Golgi v-SNAREs is an essential step for recruitment of Arf1p and coatomer, proteins that together form the COPI coat. ARF-GAP acts catalytically to recruit COPI components. Inclusion of v-SNAREs into COPI vesicles could be mediated by direct interaction with the coat. The mechanisms by which v-SNAREs interact with COPI and COPII coat proteins seem to be different and may play a key role in determining specificity in vesicle budding.
在真核细胞中，分泌是通过囊泡运输实现的。此类囊泡与正确的靶区室的融合依赖于囊泡（v-SNARE）和靶膜（t-SNARE）上的SNARE蛋白。目前尚不清楚v-SNARE是如何被整合到运输囊泡中的。在此，我们表明ADP-核糖基化因子（ARF）-GTP酶激活蛋白（GAP）与内质网-高尔基体v-SNARE的结合是招募Arf1p和外套蛋白的关键步骤，Arf1p和外套蛋白共同形成COP I衣被。ARF-GAP通过催化作用招募COP I组分。v-SNARE被纳入COP I囊泡可能是通过与衣被的直接相互作用介导的。v-SNARE与COP I和COP II衣被蛋白相互作用的机制似乎不同，可能在决定囊泡出芽的特异性方面起关键作用。
