Transport of cell adhesion molecules: How does Rab21 organise integrin trafficking on a mechanistic level?

细胞粘附分子的运输：Rab21 如何在机制水平上组织整合素运输？

• 批准号: 242476905
• 负责人: Professor Dr. Martin Aepfelbacher, since 2/2017
• 金额: --
• 依托单位: Abteilung Schiffbau und Meerestechnik, Nautik, Biologie, Bionik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/242476905?language=en
• 关键词: Transport; cell; adhesion; molecules; How

Numerous diseases such as cancer progression, inflammation and degenerative disorders are results of deregulated cell adhesion and migration. The integrin family of transmembrane cell surface receptors have a decisive impact on the migratory and invasive capacities of cancer and immune cells. Furthermore, a variety of pathogens use integrins to invade host cells for infection, extending the relevance of integrins to infectious diseases. It is becoming increasingly evident that not only activation/deactivation, but also the endo-/exocytic cycle of integrins plays an important role in mediating integrin function. The small Ras-family GTP-binding protein Rab21, which binds to the cytoplasmic tail of alpha-integrins, is a major regulator in the endocytic trafficking of integrins. However, on a molecular or structural level the mode of action remains poorly understood mainly due to the lack of known Rab21-interacting proteins.The aim of the proposed research is to gain insights how Rab21 organises integrin trafficking on a structural-mechanistic level. To answer this question, three projects will be implemented.A) Identification of Rab21 effector proteins involved in integrin trafficking.Novel Rab21 downstream effector proteins will be identified using a quantitative mass spectrometry-based protein-protein interaction screen and tested regarding their influence on integrin trafficking.B) Structural analysis of the Rab21-integrin trafficking network. After their identification, Rab21 downstream effectors as well as the cytoplasmic tail of alpha-integrins will be crystallised in complexes with Rab21 to obtain a structural snapshot of the Rab21-regulated integrin trafficking network. The X-ray structures will provide insights into the function of the trafficking complex and answer the question how Rab21 manages to transport cargo (integrin) and bind effector proteins in parallel.C) Functional analysis of the Rab21 effector proteins. I will investigate the biochemical and cell biological function of the identified effector proteins and address the question how these effector proteins effect the dynamics of integrin endocytosis. Different microscopy techniques (confocal microscopy, live cell imaging, TIRF) will be employed.In this proposed research, I will employ a multidisciplinary approach starting with a biochemical screen and combining various state of the art and cutting edge cell and structural biological tools to maximise our mechanistic understanding of the question how integrins are trafficking from the plasma membrane to endosomes and how this trafficking influences different disease processes.

癌症进展，炎症和退化性疾病等许多疾病是细胞粘附和迁移的结果。跨膜细胞表面受体的整合素家族对癌症和免疫细胞的迁移和侵入性能力有决定性的影响。此外，多种病原体使用整联蛋白来侵入宿主细胞以进行感染，从而扩展了整联蛋白与感染疾病的相关性。越来越明显的是，不仅激活/失活，而且整联蛋白的内部/外旋细胞周期在介导整联蛋白功能中起着重要作用。与α-积聚蛋白的细胞质尾巴结合的小RAS-family GTP结合蛋白Rab21是整联蛋白内吞输血中的主要调节剂。然而，在分子或结构层面上，作用方式仍然很少理解，这主要是由于缺乏已知的RAB21相互作用蛋白质。拟议的研究的目的是了解Rab21如何在结构机械水平上组织整合素。为了回答这个问题，将实施三个项目。A）鉴定RAB21效应子蛋白参与整合蛋白运输。NovelRAB21下游效应蛋白将使用基于量子质谱的蛋白质 - 蛋白质相互作用筛选进行鉴定，并对其对整合蛋白的影响进行了测试。B）结构性分析rab21-Intergicking网络。鉴定后，RAB21下游效应子以及α-积聚蛋白的细胞质尾巴将在与Rab21的复合物中结晶，以获得RAB21调节的整联蛋白运输网络的结构快照。 X射线结构将提供有关运输复合物功能的见解，并回答RAB21如何在并行中运输货物（整联蛋白）和结合效应子蛋白的功能分析Rab21效应蛋白的功能分析。我将研究已鉴定的效应蛋白的生化和细胞生物学功能，并解决这些效应蛋白如何影响整联蛋白内吞作用的动力学的问题。将采用不同的显微镜技术（共聚焦显微镜，活细胞成像，TIRF）。在这项拟议的研究中，我将采用一种从生物化学筛查开始，并结合了艺术的各种状态，并结合了艺术的各种状态，并结合了尖锐的细胞和结构生物学工具，以最大程度地传播整合素的机械性疾病，从而最大程度地传播了这种疾病。