MOLECULAR BASIS OF RAN MEDIATED NUCLEAR TRANSPORT

这项提议的广泛的长期目标是理解 RAN GTP酶驱动大分子在细胞内的双向移动 核包膜。有证据表明，RAN与 许多辅助蛋白将蛋白质移入和移出 原子核。这项建议的具体目的是：1)审查IN 对RAN功能至关重要的活体相互作用；2)测试 假设RAN-GDP结合的基本细胞作用 蛋白质，核运输因子2(NTF2)是将RAN-GDP集中在 核孔，在那里RAN被要求启动核进口；以及 3)用遗传学方法确定核孔上的位置(S) 这代表了(S)NTF2的对接地点，很可能是NTF2的对接地点- 很复杂。建议的研究使用发芽酵母 酿酒酵母作为体内遗传学和细胞生物学的模型 实验并扩展到生物化学研究，体内功能 研究，和细胞生物学实验，并扩展到生化 研究、体内功能研究和结构研究 酵母蛋白及其高度保守的人类对应蛋白。这个 这项提议与健康有关有两个方面。第一，激活信号 信号转导通路向细胞核发送信号，以便做出反应 刺激并激活转录。这通常是完成的 通过蛋白质进入细胞核的运动。信号的这一方面 经常被忽视或轻视，但它可能代表着一个未被利用的 目标是阻止特定的蜂窝信号以及 在转化的细胞中产生的不受调控的信号。第二，病毒 利用内源性核运输感染人类细胞 既能进入原子核又能迅速出口的机器 它们自己复制的遗传物质。更详细地了解 调解核运输的机制可能会提供新的目标 用于抗病毒治疗。

The broad long term objective of this proposal is to understand how the Ran GTPase drives bi-directional movement of macromolecules across the nuclear envelope. There is evidence to suggest that Ran cooperates with a number of accessory proteins to move proteins into and out of the nucleus. The specific aims of this proposal are: 1) to examine the in vivo interactions that are essential for Ran function; 2) to test the hypothesis that the essential cellular role of the Ran-GDP binding protein, nuclear transport factor 2 (NTF2) is to concentrate Ran-GDP at the nuclear pore, where Ran is required to initiate nuclear import; and 3) to use a genetic approach to define the site(s) on the nuclear pore that represent(s) the docking site for NTF2 and most probably the NTF2- Ran complex. The proposed studies use the budding yeast Saccharomyces cerevisiae as a model for in vivo genetic and cell biological experiments and extend to biochemical studies, in vivo functional studies, and cell biological experiments and extend to biochemical studies, in vivo functional studies, and structural studies of both the yeast proteins and their highly conserved human counterparts. The health-relatedness of this proposal is two-fold. First, activated signal transduction pathways send a signal to the nucleus in order to respond to stimuli and activate transcription. This is most often accomplished by the movement of a protein into the nucleus. This aspect of signaling is often ignored or trivialized, yet it may represent an unexploited targeted for blocking specific cellular signals as well as the unregulated signals that arise in transformed cells. Second, viruses that infect human cells exploit the endogenous nuclear transport machinery both to gain entry to the nucleus and later to rapidly export their own replicated genetic material. A more detailed understanding of the machinery that mediates nuclear transport may provide novel targets for anti-viral therapies.