Dynamic Membrane association of the bacterial SRP receptor in E. coli

大肠杆菌中细菌 SRP 受体的动态膜关联

• 批准号: 61723865
• 负责人: Professor Dr. Hans-Georg Koch
• 金额: --
• 依托单位: Institut für Biochemie und Molekularbiologie
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2008
• 资助国家: 德国
• 起止时间: 2007-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/61723865?language=en
• 关键词: Dynamic; Membrane; association; bacterial; SRP

During co-translational protein targeting the SRP-receptor (SR) connects the soluble SRP-ribosome nascent chain complex (RNC) to the membrane-bound SecY translocon. In eukaryotes, the SR consists of two subunits: SRα recruits the SRP-RNC to the membrane whereas SRβ is responsible for sensing vacant translocons and for coordinating RNC-transfer from SRP to the translocon. Although the bacterial SR consists of only the SRα-homolog FtsY, our data indicate that FtsY is able to execute both functions of the eukaryotic SR. This raises several crucial questions: (1) How does FtsY coordinate RNC binding to the translocon? (2) What is the translocon binding site of FtsY and how is FtsY dispelled from the translocon to expose the binding sites for the RNC? (3) Are co-translational protein targeting and integration by the SRP pathway spatially coordinated as indicated by the observation that FtsY interacts with components of the bacterial cytoskeleton? These questions will be addressed by combining in vivo techniques, such as in vivo site-directed cross-linking, FRET and fluorescence microscopy, with in vitro techniques, such as our established in vitro transcription/translation systems and reconstituted proteoliposome systems.

在共翻译过程中，靶向SRP受体（SR）的蛋白质将可溶性SRP-核糖体新生链复合物（RNC）连接到膜结合的SecY易位子上。在真核生物中，SR由两个亚基组成：SRα将SRP-RNC募集到膜上，而SRβ负责感知空的translocon并协调RNC从SRP转移到translocon。虽然细菌SR仅由SRα-同系物FtsY组成，但我们的数据表明FtsY能够执行真核SR的两种功能。这提出了几个关键问题：（1）FtsY如何协调RNC与易位子的结合？(2)FtsY的易位子结合位点是什么？FtsY是如何从易位子上消除以暴露RNC的结合位点的？(3)如FtsY与细菌细胞骨架组分相互作用的观察所示，SRP途径的共翻译蛋白靶向和整合是否在空间上协调？这些问题将通过结合体内技术，如在体内定点交联，FRET和荧光显微镜，在体外技术，如我们建立的体外转录/翻译系统和重组蛋白脂质体系统。

项目成果

The Bacterial SRP Receptor, SecA and the Ribosome Use Overlapping Binding Sites on the SecY Translocon

• DOI: 10.1111/j.1600-0854.2011.01167.x
• 发表时间: 2011-05-01
• 期刊: TRAFFIC
• 影响因子: 4.5
• 作者: Kuhn, Patrick;Weiche, Benjamin;Koch, Hans-Georg
• 通讯作者: Koch, Hans-Georg

Depletion of the Signal Recognition Particle Receptor Inactivates Ribosomes in Escherichia coli

• DOI: 10.1128/jb.00208-09
• 发表时间: 2009-11-15
• 期刊: JOURNAL OF BACTERIOLOGY
• 影响因子: 3.2
• 作者: Buerk, Jonas;Weiche, Benjamin;Koch, Hans-Georg
• 通讯作者: Koch, Hans-Georg

Dynamic Interaction of the Sec Translocon with the Chaperone PpiD*

• DOI: 10.1074/jbc.m114.577916
• 发表时间: 2014-06
• 期刊: The Journal of Biological Chemistry
• 作者: Ilie Sachelaru;Narcis-Adrian Petriman;R. Kudva;H. Koch