CRYSTALLOGRAPHIC STUDIES ON NUCLEAR PORE COMPLEX PROTEINS

该子项目是利用 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得主要资金， 因此可以在其他CRISP条目中表示。列出的机构是 中心，不一定是研究者的机构。 核孔复合物（nuclear pore complex，NPC）是真核细胞中最大的蛋白质组装体，介导核质间的转运。NPC有大约30种独特的蛋白质（称为核孔蛋白），在脊椎动物中聚集在一起形成大约125 MDa的蛋白质复合物。基于生化纯化和体外结合实验，所有的核孔蛋白已被分成几个亚复合物。 Nup 93亚复合物是NPC在核膜上正确组装的亚复合物，并维持其分子排阻极限。 Nup 93亚复合体位于NPC的核心区域，由Nup 93、Nup 205、Nup 188、Nup 35和Nup 155 5个成员组成，它们之间相互作用。我们的实验室正试图重建这个亚复合体，然后通过晶体学方法确定它的3D结构。 我们实验室的长期目标是确定单个核孔蛋白或核孔蛋白复合体的三维结构，这些蛋白质的结构信息将类似于通过NPC的核运输的快照。 目前，我们已经有了Nup 93和Nup 35晶体，它们的衍射性能很差。我们的目标是收集好的数据集，并使用MAD/MIR方法确定其三维结构 核孔蛋白的三维结构将展示细胞中最大的蛋白质组装体是如何组织的，以及调节核运输基本过程的蛋白质的结构特征，最终这些信息将引导我们了解细胞水平上生命的复杂组织。

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. The nuclear pore complex (NPC) is the largest protein assembly in eukaryotic cell, which mediate transport between nucleus and cytoplasm. NPC have approximately 30 unique proteins (known as nucleoporins), clustered together to form approximately 125 MDa protein complex in vertebrates. Based on biochemical purification and in vitro binding experiments, all nucleoporins have been grouped into several subcomplexes. One of these subcomplex, named as Nup93 subcomplex contribute to correct assembly of NPC at nuclear membrane and also maintains its size exclusion limit. Nup93 subcomplex located in the core region of NPC has Nup93, Nup205, Nup188, Nup35 and Nup155 members, which interact with each other. Our lab is trying to reconstitute this subcomplex and then determine its 3D structure by crystallographic methods. The long term goal of our lab is to determine the 3D structure of individual nucleoporins or complex of nucleoporins.The structural information of these proteins will be like snapshots of nuclear trafficking via NPC. Currently we have crystals of Nup93 and Nup35 which are diffracting poorly.The goal is to collect good data set and determine its 3D structure using MAD/MIR methods The 3D structure of nucleoporins would demonstrate how the largest protein assembly of the cell is organized and what are structural features of the proteins which regulate the fundamental process of nuclear transport.Eventually this information will led us to understand the complex organization of life at cellular level.