CHARACTERIZATION OF THE ARF FAMILY OF REGULATORY GTP-BINDING PROTEINS

这一部分涉及对其结构、功能和功能的研究 调控GTP超家族成员的作用机制 结合蛋白；特别是ADP-核糖化因子的成员 (ARF)家庭。ARF已被证明在 维持内质的完整性和正常运作 网状结构、高尔基复合体和内吞体室。ARF蛋白也 刺激磷脂酶D，可能是这一过程的直接激活剂 效应器。中国人ARF家族新成员的克隆和序列分析 人类和酵母菌，酿酒酵母，继续。目前有6个 哺乳动物ARF蛋白和6个哺乳动物ARF样蛋白的完全克隆和 已排序。此外，我们还有至少五个以上的部分序列 酵母中的成员，以及人类中的更多成员。酵母菌遗传学继续 为ARF蛋白在真核生物中的作用提供新的线索。一个 ARF1的条件致死等位基因揭示了ARF在孢子形成中的作用。 对ARF1的另一个等位基因的分析导致观察到ARF 呼吸功能也是必需的。很可能这些角色 对于ARF蛋白质来说，在这些重要的细胞过程中提供了重要的 为理解这些关键因素的作用机制提供线索 调节蛋白。双杂交技术被用来鉴定其他 ARF信号通路中的组成部分。这种方法导致了克隆 其产物与人类ARF3相互作用的6个人类基因中。北方斑点 据透露，这6个基因中的5个在多种不同的 人体组织，还有一种组织分布较有限。三位一体 解决了ArF~GDP的空间晶体结构问题。工作仍在继续 关于活性、ArF~GTP和肉豆蔻酰化ARF结构的研究 在确定关键功能域和设计特定功能域时 抑制剂。

This section is involved in studies of the structure, function and mechanism of action of members of the superfamily of regulatory GTP binding proteins; particularly the members of the ADP-ribosylation factor (ARF) family. ARF has been shown to have essential functions in the maintenance of the integrity and proper functioning of the endoplasmic reticulum, Golgi complex, and endosome compartments. ARF proteins also stimulate phospholipase D, likely serving as the direct activators of this effector. The cloning and sequencing of novel members of the ARF family in humans and the yeast, S. cerevisiae, continues. There are currently 6 mammalian ARF proteins and 6 mammalian ARF-like proteins fully cloned and sequenced. In addition, we have partial sequence of at least five more members in yeast, and several more in humans. Yeast genetics continues to provide new clues to the actions of ARF proteins in eukaryotes. A conditional lethal allele of ARF1 revealed a role for ARF in sporulation. Analysis of another allele of arf1 led to the observation that ARF function is also required for respiration. It is likely that the roles for ARF proteins in these essential cellular processes provide important clues toward understanding the mechanisms of action of these critical regulatory proteins. The two-hybrid technique was used to identify other components in an ARF signaling pathway. This approach led to the cloning of 6 human genes whose products interact with human ARF3. Northern blots revealed that five of these 6 genes are expressed in a wide variety of human tissues, and one with a more limited tissue distribution. The three dimensional crystal structure of ARF~GDP has been solved. Work continues on the active, ARF~GTP and myristoylated ARF structures as each should aid in the determination of critical functional domains and design of specific inhibitors.