Systematic analysis of polarised trafficking during cell motility

细胞运动过程中极化运输的系统分析

• 批准号: BB/H002308/1
• 负责人: Joshua Rappoport
• 金额: $ 42.99万
• 依托单位: University of Birmingham
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2009
• 资助国家: 英国
• 起止时间: 2009 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FH002308%2F1
• 关键词: Systematic; analysis; polarised; trafficking; during

Epithelial cells form a barrier between different compartments in the body. The outer layer of skin is formed from epithelial cells, and protects our internal organs from the external environment. A single layer of epithelial cells also separates the air space in our lungs from the blood vessels, and produces the barrier in the intestine across which digested food travels. When wounds form, such as cutting a finger on a kitchen knife, epithelial cells move by crawling forward to close up the newly exposed area. This crawling is referred to as cell motility. Improper wound healing can result in scar formation. With wounds to the skin, this might only pose a cosmetic issue; however, inside the body, this can be much more serious. One such medically relevant case can occur when dust and dirt is inhaled into the lungs. The small wounds to the epithelial barrier of the lung must properly heal, or a condition known as pulmonary fibrosis can result. If this occurs the epithelial layer across which oxygen is absorbed is replaced by scar tissue, which is not able to exchange gas properly. Thus, it is of great importance to understand the mechanisms that control epithelial cell motility, and this information could lead to the development of new treatments to promote wound healing and limit scar formation. Similar to the way our skin protects the inside of the body, the plasma membrane forms a barrier between the inside of cells, the cytosol, and the outside, extracellular, space. Many proteins reside in the plasma membrane and provide a linkage between the cytosol and extracellular space. These include channels and pumps that let specific substances into or out of cells, receptors for extracellular signals that cells send to each other, as well as adhesion proteins that permit cells to stick to each other, and the extracellular environment, or matrix. The number of these membrane proteins, as well as the activity and specific location within the plasma membrane, is controlled by a process known as vesicle trafficking. Vesicles are specialised carriers that transport cargo, such as membrane proteins, between different locations in the cell. The insertion of proteins into the plasma membrane occurs through exocytosis, while retrieval into the cytosol is achieved via endocytosis. Several different sub-pathways of exocytosis and endocytosis exist which can traffic specific cargo in response to particular cues. One main goal of this project is to determine which vesicle trafficking pathways are important in epithelial cell motility. Understanding of the trafficking of specific cargo could be harnessed to potentially stimulate wound healing. Techniques exist whereby a single vesicle trafficking process can be specifically inhibited, and by measuring subsequent effects on cell motility, particular pathways relevant to wound healing will be identified. Furthermore, through application of cutting edge microscopy we are able to image individual events of endocytosis and exocytosis, as well as the movement of single vesicles in the cytosol. This technology will be used to test the hypothesis that trafficking of cell adhesion proteins known as integrins from one area of the cell (e.g. the back edge) to another (e.g. the front edge) could drive cell motility. This will directly evaluate the 'polarised recycling model for cell motility', which suggests that back-to-front trafficking of adhesion proteins could drive a cell forward in a manner analogous to a tank tread. Finally, we will apply innovative computational approaches to analyse live-cell microscopy data to permit a systematic analysis of the role of vesicle trafficking in epithelial cell motility. Results stemming from this project could provide valuable information regarding the regulation of cell motility and could lead to the development of new therapies that could increase the rate of wound healing.

上皮细胞形成体内不同隔室之间的障碍。皮肤的外层由上皮细胞形成，并保护我们的内部器官免受外部环境的侵害。单层上皮细胞还将我们的肺中的空气空间与血管分开，并在消化食物传播的肠中产生障碍物。当形成伤口（例如在厨房上切手指）时，上皮细胞向前爬行以封闭新裸露的区域而移动。这种爬行称为细胞运动。伤口愈合不当会导致疤痕形成。由于皮肤的伤口，这可能只会构成美容问题。但是，在体内，这可能更加严重。当将灰尘和污垢吸入肺中时，可能会发生一种与医学相关的情况。肺上皮屏障的小伤口必须适当愈合，或者可能导致称为肺纤维化的疾病。如果发生这种情况，将氧气吸收的上皮层被疤痕组织所取代，疤痕组织无法正常交换气体。因此，了解控制上皮细胞运动的机制非常重要，并且该信息可能导致开发新疗法以促进伤口愈合并限制疤痕形成。与我们的皮肤保护人体内部的方式相似，质膜在细胞内部，细胞质和外部，细胞外空间之间形成障碍。许多蛋白质位于质膜中，并在细胞质和细胞外空间之间提供连接。这些包括将特定物质进入或流出细胞的通道和泵，细胞彼此发送的细胞外信号的受体，以及允许细胞彼此粘附的粘附蛋白，细胞外环境或基质。这些膜蛋白的数量以及质膜内的活性和特定位置受称为囊泡运输的过程控制。囊泡是在细胞中不同位置之间运输货物（例如膜蛋白）的专业载体。将蛋白质插入质膜中是通过胞吐作用发生的，而通过内吞作用可实现进入细胞质。存在几种不同的胞吞和内吞作用的子轨道，可以响应特定的提示来交通特定的货物。该项目的主要目标是确定哪些囊泡运输途径在上皮细胞运动中很重要。了解对特定货物的贩运的理解可以利用可能刺激伤口愈合。存在技术，可以特别抑制单个囊泡运输过程，并通过测量对细胞运动的影响，将确定与伤口愈合相关的特定途径。此外，通过使用尖端显微镜，我们能够对内吞作用和胞吐作用的个体事件进行图像，以及细胞质中单囊泡的运动。该技术将用于检验以下假设：细胞粘附蛋白从细胞的一个区域（例如后缘）到另一个区域（例如，前沿）的运输被称为整联蛋白。这将直接评估“细胞运动的两极分化回收模型”，这表明粘附蛋白的倒流运输可以以类似于储罐胎面的方式向前驱动细胞。最后，我们将采用创新的计算方法来分析活细胞显微镜数据，以系统地分析囊泡运输在上皮细胞运动中的作用。来自该项目的结果可以提供有关细胞运动调节的有价值信息，并可能导致新疗法的发展，这些疗法可能会增加伤口愈合的速度。

项目成果

Mutations in VIPAR cause an arthrogryposis, renal dysfunction and cholestasis syndrome phenotype with defects in epithelial polarization.

• DOI: 10.1038/ng.538
• 发表时间: 2010-04
• 期刊: Nature genetics
• 影响因子: 30.8
• 作者: Cullinane AR;Straatman-Iwanowska A;Zaucker A;Wakabayashi Y;Bruce CK;Luo G;Rahman F;Gürakan F;Utine E;Ozkan TB;Denecke J;Vukovic J;Di Rocco M;Mandel H;Cangul H;Matthews RP;Thomas SG;Rappoport JZ;Arias IM;Wolburg H;Knisely AS;Kelly DA;Müller F;Maher ER;Gissen P
• 通讯作者: Gissen P

Functional analysis of Dictyostelium IBARa reveals a conserved role of the I-BAR domain in endocytosis.

• DOI: 10.1042/bj20101684
• 发表时间: 2011-05
• 期刊: The Biochemical journal
• 作者: Douwe M Veltman;Giulio Auciello;H. Spence;L. Machesky;J. Rappoport;R. Insall