EXOMER COMPLEX

外显子复合体

• 批准号: 8363377
• 负责人: J Christopher Fromme
• 金额: $ 0.29万
• 依托单位: BROOKHAVEN SCIENCE ASSOC-BROOKHAVEN LAB
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-01 至 2012-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8363377
• 关键词: Adaptor Signaling Protein; Binding; Biochemical; Biological Assay; Capsid Proteins; Carrier Proteins; Cell Cycle; Cell membrane; Clathrin Adaptors; Complex; Crystallography; Data Set; Devices; Funding; Grant; Home environment; L-Selenomethionine; Light; Membrane; Modeling; Monitor; Names; National Center for Research Resources; Play; Principal Investigator; Process; Protein Binding; Proteins; Research; Research Infrastructure; Resort; Resources; Roentgen Rays; Role; Shapes; Source; Stress; Synchrotrons; System; United States National Institutes of Health; Vesicle; Yeasts; beamline; cost; interest; response; trafficking; trans-Golgi Network

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. Transport of proteins between membrane-bound compartments is a tightly regulated process involving vesicular membrane carriers. A classical membrane vesicle is created by membrane deformation achieved in part by cytosolic "coat" proteins. Coat proteins bind and shape membranes, and they also play an important role in selecting cargo incorporated into transport carriers. Recent studies have established the existence of a new membrane coat complex responsible for trafficking certain cargo proteins from the trans-Golgi network (TGN) to the plasma membrane in yeast. This coat, named "Exomer", is interesting as an alternative to the better-known TGN coat systems involving Clathrin and Adaptor Proteins. Exomer is also quite interesting as a model for regulated transport. Under steady-state conditions, cargo trafficked by exomer is localized in a stable internal compartment, but in response to stress or progression through the cell-cycle cargo is rapidly mobilized to the plasma membrane in a polarized manner. The proper localization of two Exomer cargo proteins in particular (Chs3 and Fus1) is easily monitored by simple assays, making this an excellent system for in-depth mechanistic studies. We are pursuing structural and biochemical studies of Exomer in order to understand how it functions. We currently have diffracting crystals of a fully functional exomer complex, having collected a native 2.8A dataset on the CHESS A1 beamlime. We are unable to grow crystals of the SeMet-substituted protein, so we are now resorting to heavy-atom soaks for MIR/MIRAS/SIRAS. We are unable to screen for derivatives on a home source because our crystals do not diffract strongly enough using home-source X-rays. An insertion device beamline is ideal, as the best we can do is 2.8A at CHESS A1. We also would like to take advantage of tunable wavelength for attempts at MIRAS/SIRAS.

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。 蛋白质在膜结合区室之间的转运是一个涉及囊泡膜载体的严格调节的过程。 经典的膜囊泡是由部分由细胞质“外壳”蛋白实现的膜变形产生的。 外壳蛋白结合并形成膜，并且它们在选择并入运输载体的货物方面也发挥重要作用。 最近的研究已经确定了一种新的膜包被复合物的存在，该复合物负责将某些货物蛋白从trans-Golgi网络（TGN）运输到酵母中的质膜。 这种被命名为“外聚体”的外壳作为涉及网格蛋白和衔接蛋白的更知名的TGN外壳系统的替代物是有趣的。 外消旋体作为调节运输的模型也很有趣。 在稳态条件下，由外消旋体运输的货物被定位在稳定的内部隔室中，但是响应于通过细胞周期的应激或进展，货物以极化方式被快速动员到质膜。特别是两种外消旋体货物蛋白（Chs 3和Fus 1）的适当定位很容易通过简单的测定进行监测，使其成为深入机制研究的优秀系统。 我们正在进行Exomer的结构和生物化学研究，以了解它的功能。 我们目前拥有一个功能齐全的外消旋体复合物的衍射晶体，在CHESS A1光束上收集了一个天然的2.8A数据集。 我们无法生长SeMet取代蛋白质的晶体，因此我们现在诉诸于重原子浸泡MIR/MIRAS/SIRAS。 我们无法筛选来自家庭来源的衍生物，因为我们的晶体在使用家庭来源的X射线时没有足够强的反射性。 插入设备光束线是理想的，因为我们可以在CHESS A1处做的最好是2.8A。 我们还希望利用可调谐波长来尝试MIRAS/SIRAS。