YEAST NUCLEAR PORE COMPLEX: TRANSPORT MECHANISM

酵母核孔复合物：运输机制

• 批准号: 8169095
• 负责人: MICHAEL P ROUT
• 金额: $ 1.16万
• 依托单位: ROCKEFELLER UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-03-01 至 2011-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8169095
• 关键词: Accounting; Affinity; Architecture; Binding; Binding Sites; Cell Nucleus; Cells; Cellular biology; Computer Retrieval of Information on Scientific Projects Database; Data; Devices; Diffusion; Equipment and supply inventories; Funding; Grant; Institution; Kinetics; Knowledge; Manuscripts; Maps; Measurement; Mediating; Modeling; Molecular; Nuclear Pore Complex; Nuclear Pore Complex Proteins; Physics; Production; Property; Proteins; Publications; Publishing; Research; Research Personnel; Resources; Route; Sorting - Cell Movement; Source; Structure; Testing; Transport Process; United States National Institutes of Health; Work; Yeasts; base; flexibility; in vivo; macromolecule; nucleocytoplasmic transport; research study; trend

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. An understanding of how the nuclear pore complex (NPC) mediates nucleocytoplasmic exchange requires a comprehensive inventory of the molecular components of the NPC and a knowledge of how each component contributes to the overall structure of this large molecular translocation machine. Therefore, we have taken a comprehensive approach to classify all components of the yeast NPC (nucleoporins). This involved identifying all the proteins present in a highly enriched NPC fraction, determining which of these proteins were nucleoporins, and localizing each nucleoporin within the NPC. Using these data, we present a map of the molecular architecture of the yeast NPC and provide evidence for a Brownian affinity gating mechanism for nucleocytoplasmic transport. This work has been published (M.P. Rout, J.D. Aitchison, A. Suprapto, K. Hjertaas, Y-M. Zhao, B.T. Chait, J. Cell. Biol. 148 (2000) 635-651)and M.P. Rout, J.D. Aitchison, M.O. Magnasco, B.T. Chait, Trends Cell Biology 13(2003)622-628. We are currently testing our model for nuclear transport using three different approaches: in vivo measurements of transport kinetics; production of an artificial NPC; and physics-based modeling of the gating/transport processes. All materials enter or exit the cell nucleus through nuclear pore complexes (NPCs), efficient transport devices that combine high selectivity and throughput. NPC-associated proteins containing phenylalanineglycine repeats (FG nups) have large, flexible, unstructured proteinaceous regions, and line the NPC. A central feature of NPC-mediated transport is the binding of cargo-carrying soluble transport factors to the unstructured regions of FG nups. Here, we model the dynamics of nucleocytoplasmic transport as diffusion in an effective potential resulting from the interaction of the transport factors with the flexible FG nups, using a minimal number of assumptions consistent with the most well-established structural and functional properties of NPC transport. We discuss how specific binding of transport factors to the FG nups facilitates transport, and how this binding and competition between transport factors and other macromolecules for binding sites and space inside the NPC accounts for the high selectivity of transport. We also account for why transport is relatively insensitive to changes in the number and distribution of FG nups in the NPC, providing an explanation for recent experiments where up to half the total mass of the FG nups has been deleted without abolishing transport. Our results suggest strategies for the creation of artificial nanomolecular sorting devices. A manuscript describing this work has been submitted for publication.

该副本是利用众多研究子项目之一 由NIH/NCRR资助的中心赠款提供的资源。子弹和 调查员（PI）可能已经从其他NIH来源获得了主要资金， 因此可以在其他清晰的条目中代表。列出的机构是 对于中心，这不一定是调查员的机构。 对核孔复合物（NPC）如何介导核细胞质交换的理解需要全面库存NPC的分子成分，并了解每个成分如何促进这台大分子易位机的整体结构。 因此，我们采取了一种全面的方法来对酵母NPC（核孔）的所有组成部分进行分类。这涉及确定在高度富集的NPC馏分中存在的所有蛋白质，确定这些蛋白质中的哪种是核孔蛋白，并将每个核孔定位在NPC中。 使用这些数据，我们介绍了酵母NPC的分子结构的地图，并为核质传输的Brownian亲和门控机制提供了证据。 这项工作已发表（M.P. Rout，J.D。Aitchison，A。Suprapto，K。Hjertaas，Y-M。Zhao，B.T。Chait，J.Cell。Biol。148（2000）148（2000）635-651）和M.P.鲁特（J.D. Aitchison），M.O。 Magnasco，B.T。 Chait，趋势细胞生物学13（2003）622-628。我们目前正在使用三种不同的方法测试我们的核运输模型：运输动力学的体内测量；生产人造NPC；以及基于物理的门控/运输过程的建模。 所有材料都通过核孔复合物（NPC）进入或退出细胞核，有效的运输设备，结合了高选择性和吞吐量。 NPC相关的蛋白质含有苯丙氨酸甘氨酸重复量（FG NUP）具有较大，柔性，非结构化的蛋白质区域，并在NPC上排成一列。 NPC介导的运输的主要特征是载货物的可溶性运输因子与FG NUP的非结构化区域的结合。在这里，我们使用最小数量的假设与NPC转运的最完善的结构和功能性能一致，因此，我们将核质转运的动力学建模为由于转运因子与柔性FG NUP的相互作用而产生的有效潜力的扩散。我们讨论转运因子与FG NUP的特定结合如何促进运输，以及用于结合位点和NPC内部空间的运输因子与其他大分子之间的这种结合和竞争如何说明了运输的高选择性。我们还解释了为什么运输对NPC中FG NUP的数量和分布的变化相对不敏感，从而为最近的实验提供了解释，在这些实验中，最多一半的FG NUP质量已被删除而无需废除运输。我们的结果表明了创建人工纳米分子分类设备的策略。 描述这项工作的手稿已提交出版。