THE PROTEIN-CONDUCTING CHANNEL

蛋白质传导通道

• 批准号: 8363649
• 负责人: JAMES C GUMBART
• 金额: $ 4.97万
• 依托单位: UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-08-01 至 2012-09-09
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8363649
• 关键词: Archaea; Back; Bacteria; Behavior; Beryllium; Bioinformatics; Cell membrane; Cells; Complex; Endoplasmic Reticulum; Eukaryota; Feeds; Funding; Grant; Insulin; Left; Life; Membrane; Membrane Proteins; Methanococcus; Modeling; National Center for Research Resources; Principal Investigator; Prions; Proteins; Research; Research Infrastructure; Resolution; Resources; Ribosomes; Role; Source; Structure; United States National Institutes of Health; base; cost; dimer; in vivo; monomer; polypeptide; protein complex; Archaea; Back; Bacteria; Behavior; Beryllium; Bioinformatics; Cell membrane; Cells; Complex; Endoplasmic Reticulum; Eukaryota; Feeds; Funding; Grant; Insulin; Left; Life; Membrane; Membrane Proteins; Methanococcus; Modeling; National Center for Research Resources; Principal Investigator; Prions; Proteins; Research; Research Infrastructure; Resolution; Resources; Ribosomes; Role; Source; Structure; United States National Institutes of Health; base; cost; dimer; in vivo; monomer; polypeptide; protein complex

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 protein-conducting channel, more specifically known as the translocon (http://www.ks.uiuc.edu/Research/translocon/) or Sec complex, is an evolutionarily ancient protein complex that helps proteins cross or integrate into membranes (depending on whether they are soluble or membrane proteins). Present in all branches of life, the Sec complex is found in the cytoplasmic membrane in bacteria and archaea and in the membrane of the endoplasmic reticulum in eukaryotes. A passive channel, the Sec complex partners with other proteins that drive translocation of an unfolded polypeptide through the channel. In co-translational translocation, a common mode of translocation, this partner is the ribosome which feeds the nascent protein through the channel as it is synthesized. As a key step in protein targeting, translocation can be a deciding factor in the fate of proteins and even the cell as a whole. For example, poor recognition of the prion protein (PrP) leads to its abnormal aggregation and ultimately to lethal levels in the cell [1]. However, being able to enhance recognition and passage across the membrane could increase yields for artificially created proteins such as insulin [2]. In 2004, the Resource's collaborator, Tom Rapoport, released the first high resolution structure of the translocon. Obtained from Methanococcus jannaschii, this heterotrimeric membrane protein complex was resolved to 3.5 Angstroms. Based on this structure, specific details of translocation began to emerge. Observed structural elements were proposed to have specific functions, such as a constrictive pore ring and a plug blocking the exit of the channel. It was also proposed that a singular monomer within a dimeric or tetrameric complex serves as the active channel, leaving the role of oligomerization in question. Two dimeric forms of the channel with different functional behavior have been proposed (a 'back-to-back' and a 'front-to-front' dimer) although which is the in vivo state is unknown.

该副本是利用资源的众多研究子项目之一 由NIH/NCRR资助的中心赠款提供。对该子弹的主要支持 而且，副投影的主要研究员可能是其他来源提供的 包括其他NIH来源。 列出的总费用可能 代表subproject使用的中心基础架构的估计量， NCRR赠款不直接向子弹或副本人员提供的直接资金。 蛋白质导向通道，更明确称为易位 （http://www.ks.uiuc.edu/research/translocon/） 可帮助蛋白质交叉或整合到膜中的古代蛋白质复合物 （取决于它们是可溶性还是膜蛋白）。存在于所有分支 生命，SEC复合物在细菌和古细菌的细胞质膜中发现 真核生物中内质网的膜。 被动渠道，SEC 与其他蛋白质的复杂合作伙伴，这些蛋白质驱动展开多肽的易位 通过频道。在共译性易位（一种常见的易位方式）中 该伴侣是核糖体，它通过通道喂养新生蛋白 合成。作为蛋白质靶向的关键步骤，易位可能是决定因素 蛋白质甚至整个细胞的命运。例如，对 prion蛋白（PRP）导致其异常聚集，并最终达到致命水平 细胞[1]。 但是，能够增强识别和通过膜的识别 可以增加人为产生的蛋白质（例如胰岛素）的产量[2]。在2004年 Resource的合作者Tom Rapoport发布了第一个高分辨率结构 易位。该异三个膜从Jannaschii获得的甲虫球菌获得 将蛋白质复合物分辨到3.5埃。基于此结构，具体细节 易位开始出现。提出观察到的结构元素具有 特定功能，例如收缩的孔环和插头阻塞的出口 渠道。还建议在二聚体或四聚体内的单数单体 复杂充当活跃的通道，留下了相关的低聚的作用。二 已经提出了具有不同功能行为的通道的二聚体形式（a “背对背”和“前到前”二聚体），尽管这是体内状态的未知。