PSEUDO-ATOMIC STRUCTURE OF THE NUCLEAR PORE COMPLEX (NPC) USING SAXS

使用 SAXS 分析核孔复合体 (NPC) 的伪原子结构

• 批准号: 8362058
• 负责人: HIROTSUGU TSURUTA
• 金额: $ 0.14万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-03-01 至 2012-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8362058
• 关键词: Architecture; Benchmarking; Cell Nucleus; Cell physiology; Data; Eukaryota; Funding; Genetic Transcription; Grant; Head; Homologous Gene; Malignant Neoplasms; N-terminal; National Center for Research Resources; Nuclear Envelope; Nuclear Pore Complex; Nuclear Pore Complex Proteins; Play; Positioning Attribute; Principal Investigator; Proteins; RNA; Radiation; Relative (related person); Research; Research Infrastructure; Resolution; Resources; Solutions; Source; Structure; Tail; United States National Institutes of Health; Universities; Work; Yeasts; base; cost; dimer; human disease; improved; macromolecule; protein complex; restraint; structural biology

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The Nuclear Pore Complex (NPC, about 50 MDa) is the sole passageway for the transport of macromolecules across the nuclear envelope. The pore plays a key role in numerous critical cellular processes such as transcription, and many of its components are implicated in human diseases such as cancer. The recent work by the Sali group provided the first description of the macromolecular architecture of the yeast NPC. This structure defined the relative positions and proximities of its 456 constituent nucleoporin (nup) proteins, based on spatial restraints derived from experimental data. Further elucidation of the evolutionary origin and transport mechanism of the NPC will require higher resolution information. To help improve upon the resolution and accuracy of the NPC structure, we have begun small angle x-ray scattering studies at SSRL. Individial nup proteins and complexes are being expressed, produced and purified by our collaborators at Rockefeller University and Eli Lilly on a regular basis. We selected several nup proteins whose crystal structures have been solved to establish a benchmark. Among them is Nup145 which belongs to a highly conserved group of homologs found throughout the eukaryotes. Nup145N, the autoproteolised N-terminal half of the protein has been implicated in carrying RNA between the nucleus and the NPC by its analogy with Nup98. The crystal structures of Nup145N(443-605) and Nup98N, however, shows different modes of association within their respective crystallographic asymmetric units. Our preliminary solution x-ray scattering results demonstrate that Nup145N(443-605) forms the head-to-tail dimer in solution as observed in the asymmetric units of two different space groups.

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 核孔复合物（NPC，约50 MDa）是大分子物质穿过核膜的唯一通道。孔在许多关键的细胞过程中起着关键作用，如转录，其许多组分与人类疾病如癌症有关。Sali小组最近的工作首次描述了酵母NPC的大分子结构。这种结构定义了它的456个组成核孔蛋白（nup）蛋白的相对位置和接近度，基于来自实验数据的空间限制。进一步阐明NPC的进化起源和运输机制将需要更高分辨率的信息。为了帮助提高NPC结构的分辨率和精度，我们已经开始在SSRL进行小角度X射线散射研究。我们在洛克菲勒大学和礼来公司的合作者定期表达、生产和纯化单个nup蛋白和复合物。我们选择了几个nup蛋白的晶体结构已经解决，以建立一个基准。其中Nup 145属于在整个真核生物中发现的高度保守的同源物组。Nup 145 N，蛋白质的N-末端自蛋白水解的一半，通过其与Nup 98的类似性，已经涉及在细胞核和NPC之间携带RNA。然而，Nup 145 N（443-605）和Nup 98 N的晶体结构在其各自的晶体学不对称单元内显示出不同的缔合模式。我们初步的溶液X射线散射结果表明，Nup 145 N（443-605）形成的头到尾的二聚体在溶液中观察到的两个不同的空间群的不对称单位。