Study of Cell Adhesion through an Analysis of Myosin 7

通过肌球蛋白 7 的分析研究细胞粘附

• 批准号: 7471959
• 负责人: MARGARET A TITUS
• 金额: $ 18.06万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-08-01 至 2011-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7471959
• 关键词: Actins; Address; Adhesions; Adhesives; Affinity; Affinity Chromatography; Amoeba genus; Binding; Biochemical; Biological Assay; Biological Models; Cell Adhesion; Cell Adhesion Molecules; Cell Line; Cell membrane; Cells; Classification; Complex; Cytoskeleton; Dictyostelium; ECM receptor; Ensure; Evolution; Exhibits; Focal Adhesions; Genetic Screening; Goals; Immune system; In Vitro; Infection; Injury; Leukocytes; Link; Measures; Membrane; Membrane Lipids; Molecular; Motor; Motor Activity; Movement; Myosin ATPase; Nature; Nonmuscle Myosin Type IIB; Null Lymphocytes; Phenotype; Phylogeny; Play; Property; Proteins; Regulation; Role; Site; Tail; Talin; TimeLine; Tissues; Work; Yeasts; base; cell motility; defined contribution; fighting; insight; mutant; paxillin; protein complex; receptor; research study; residence; social; tool; ward; yeast two hybrid system

The body's first line of defense against infection is the circulating white blood cells that detect and respond to tissue damage. These cells move rapidly towards the site of injury using an amoeboid type of motility. This movement is characterized by the formation of broadly distributed, low affinity contacts between the cell and surrounding substrate. The amoeboid adhesions generated by leukocytes are composed of many of the same components as the tightly organized, high affinity adhesions formed by slowly moving fibroblastic cells (focal contacts), but the organization and regulation of these molecules is distinct in amoeboid cells. Identifying the distinct mechanisms by which shared adhesion molecules are employed in amoeboid cells versus fibroblastic cells is key to understanding how rapid cell migration is achieved. The cell adhesion machinery that provides a dynamic link between extracellular matrix receptors and the actin cytoskeleton has been conserved throughout evolution. An unexpected role for a highly conserved unconventional myosin, myosin VII (M7), in amoeboid adhesion has been discovered in the amoeba Dictyostelium. The goal of this project is to define the role of M7 amoeboid adhesion. The first question that will be addressed is how M7 is targeted to adhesion sites, a critical step towards understanding the relationship between this motor protein and the cell adhesion machinery. The contribution of the conserved M7 tail domains to M7 localization, membrane dynamics and cellular adhesion will be systematically investigated. Essential domains will then be used as probes to identify binding partners (most likely other adhesion molecules or regulators). The next question is whether M7 motor activity is required for its role in amoeboid adhesion. M7 could participate in adhesion by passively linking adhesion components to the cytoskeleton or it could be required to generate tension at sites of adhesion. Cells expressing M7 motor mutants (either strong or weak actin binding) will be characterized to determine if cycles of M7 interaction with actin are necessary for its role in amoeboid adhesion. An in vitro analysis of the motor properties of M7 will also be performed to determine if it has the potential to function as an anchor or a transport motor. The results of this study will provide basic new insights into the molecular basis of amoeboid adhesion and how a myosin contributes to this critical type of adhesion to promote rapid cell migration.

人体针对感染的第一道防线是循环的白细胞 检测并应对组织损伤。这些细胞迅速向受伤部位移动 使用变形虫类型的运动性。该运动的特征是形成 细胞和周围底物之间的广泛分布，低亲和力接触。这 白细胞产生的变形虫粘连由许多相同 组件作为紧密组织的高亲和力粘附，由缓慢移动而形成 成纤维细胞（焦点接触），但这些分子的组织和调节 在变形虫细胞中是不同的。确定共享的不同机制 粘附分子用于变形虫细胞与成纤维细胞中的粘附分子是至关重要的 了解细胞迁移的快速迁移。 细胞粘附机制，在细胞外基质之间提供动态联系 在整个进化过程中，受体和肌动蛋白细胞骨架一直保守。一个 高度保守的非常规肌球蛋白肌球蛋白VII（M7）的意外角色， 在Amoeba Dictyostelium中发现了变形虫粘附。目标的目标 项目是定义M7变形虫粘附的作用。第一个问题 解决的是M7针对粘附部位的方式，这是迈向理解的关键一步 该运动蛋白与细胞粘附机械之间的关系。这 保守的M7尾域对M7定位的贡献，膜动力学 细胞粘附将被系统地研究。那么基本领域将是 用作识别结合伴侣的探针（最有可能其他粘附分子或 监管机构）。下一个问题是M7运动活动是否需要 变性粘附。 M7可以通过被动连接粘附来参与粘附 细胞骨架的成分，或者可能需要在 粘附。表达M7运动突变体的细胞（强或弱肌动蛋白结合）将 以确定M7与肌动蛋白相互作用的循环是否需要表征 在变形虫粘附中的作用。对M7的电机特性的体外分析也将是 执行以确定其是否有可能充当锚或运输的潜力 发动机。这项研究的结果将为分子基础提供基本的新见解 变性粘合剂以及肌球蛋白如何对这种关键类型的粘附有效 促进快速细胞迁移。