Small G proteins play a central role in the organization of the secretory and endocytic pathways. The majority of such small G proteins are members of the Rab family, which are anchored to the bilayer by C-terminal prenyl groups. However, the recruitment of some effectors, including vesicle coat proteins, is mediated by a second class of small G proteins that is unique in having an N-terminal amphipathic helix that becomes available for membrane insertion upon GTP binding. Sar1, Arf1, and Arf6 are the best-characterized members of this ADP-ribosylation factor (Arf) family. In addition, all eukaryotes contain additional distantly related G proteins, often called Arf like, or Arls. The complete Arf family in humans has 29 members. The roles of these related G proteins are poorly understood, but recent work has shown that some are involved in membrane traffic or organizing the cytoskeleton. Here we review what is known about all the members of the Arf family, along with the known regulatory molecules that convert them between GDP- and GTP-bound states.

中文翻译：

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Arf 家族的小 G 蛋白及其调节剂。

小 G 蛋白在分泌和内吞途径的组织中起核心作用。大多数此类小 G 蛋白是 Rab 家族的成员，它们通过 C 端异戊二烯基固定在双层上。然而，一些效应子（包括囊泡外壳蛋白）的募集是由第二类小 G 蛋白介导的，该蛋白具有独特的 N 端两亲螺旋，可用于 GTP 结合后的膜插入。Sar1、Arf1 和 Arf6 是这个 ADP 核糖基化因子 (Arf) 家族中最典型的成员。此外，所有真核生物都含有额外的远缘 G 蛋白，通常称为 Arf 样或 Arls。人类完整的 Arf 家族有 29 个成员。这些相关 G 蛋白的作用知之甚少，但最近的研究表明，其中一些参与了膜运输或组织细胞骨架。在这里，我们回顾了关于 Arf 家族所有成员的已知信息，以及将它们在 GDP 和 GTP 结合状态之间转换的已知调节分子。