THE ARF FAMILY AS REGULATORS OF PROTEIN SECRETION AND OTHER CELLULAR PROCESSES

这一部分涉及到对生物多样性的功能和机制的研究。 调节GTP结合蛋白超家族成员的作用； 尤其是ADP-核糖化因子(ARF)家族的成员。 ARF蛋白在结构和功能上都是一个亚家族 保守的21 kDa GTP结合蛋白。ARF现在已经被证明有 在维护完整性和正当性方面的基本职能 高尔基复合体的功能。目前的工作重点是 关于序列来描述这个家族的成员， 蜂窝位置和功能。 我们发现，在人类中，这个家庭不仅由 五种先前确定的基因产品，但超过10种 结构上相关的基因及其产物。我们从事的是克隆技术 并对这个新扩大的家族进行测序，开始记录它的大小， 对细胞生理学和病理生理学的作用和重要性。在……里面 此外，随着序列信息变得可用，我们继续 生产更多用于诊断目的的特异性抗血清 免疫定位。 我们继续开发更简单的真核生物，特别是 酵母，以确定ARF蛋白的新功能。我们将表演 功能筛查以确定ARF突变的基因外抑制物 努力确定ARF途径的其他组成部分和潜力 ARF活动的监管者。ARF被发现需要用于 这种生物和ARF2的产孢量比ARF1强得多 这项活动。一些突变体也在酵母中表达 作为目前正在进行的类似研究的背景，以表示 哺乳动物细胞中野生型和突变型ARF蛋白的培养。一个 详尽的筛查现已确定至少一个温度敏感度 ARF1的等位基因将被用来辅助定义ARF的功能， Arf空单元格的结果，以及外源基因的功能筛选 Arf空单元格的抑制器。

This section is involved in studies of the functions and mechanisms of action of members of the superfamily of regulatory GTP binding proteins; particularly the members of the ADP-ribosylation factor (ARF) family. The ARF proteins are a subfamily of structurally and functionally conserved 21 kDa GTP binding proteins. ARF has now been shown to have essential functions in the maintenance of the integrity and proper functioning of the Golgi complex. Current work has focused on characterizing the members of this family with regard to sequence, cellular location, and functions. We have discovered that in humans this family consists not only of the five previously identified gene products, but of more than 10 structurally related genes and their products. We are engaged in cloning and sequencing this newly enlarged family to begin to document its size, functions and importance to cell physiology and pathophysiology. In addition, as sequence information becomes available we continue to produce more specific antisera for diagnostic purposes and immunolocalization. We have continued to exploit simpler eukaryotic organisms, particularly yeast, to identify new functions for ARF proteins. We will perform functional screens to identify extragenic suppressors of ARF mutations in efforts to identify other components of the ARF pathway and potential regulators of ARF activities. ARF was found to be required for sporulation in this organism and ARF2 is much more potent than ARF1 in this activity. Expression of a number of mutants in yeast has also served as background for similar studies now underway to express wild-type and mutant ARF proteins in mammalian cells in culture. An exhaustive screen has now identified at least one temperature sensitive allele of ARF1 which will be used to assist in defining functions of ARF, consequences of an arf null cell, and functional screens for extragenic suppressors of the arf null cell.