Mechanisms of cytoskeletal crosstalk during cellular motility

细胞改变其形状的能力对大多数生物体的个体发育至关重要。在组织中，对于 例如，细胞形态的变化在形态发生期间驱动组织重塑， 对伤口修复至关重要。在单个细胞的水平上，形状变化的周期允许一些细胞 在胚胎发生、免疫功能和（更隐蔽地）转移过程中迁移的类型。 细胞形态由细胞骨架-肌动蛋白丝和微管的网络决定。 该项目的长期目标是了解细胞生物学的基本原理和机制， 通过研究调控和整合细胞骨架的途径， 动力学重要的是，肌动蛋白和微管的网络并不是孤立地起作用的，而是有 一个前所未有的程度的串扰，监管的相互作用和机械的相互作用。 微管加末端跟踪蛋白（或+TIPs）是一类选择性定位于 生长和收缩的微管的尖端。自1999年被发现以来， 参与几乎所有微管依赖性细胞功能，包括微管调节 动态不稳定性，细胞器和染色体运输，有丝分裂纺锤体的组装， 细胞极性的建立和细胞迁移。在本提案中，我们重点关注+TIPs， 特别强调肌动蛋白微管的串扰，因为这代表了一个相对未探索的 两个细胞骨架网络之间的功能界面。我们的核心假设是微管 正端是动态平台，将信息传递到控制细胞的皮层调节网络， 也是肌动蛋白和微管之间结构整合的场所。我们将测试 这些想法使用了我们用培养的果蝇细胞系作为模型开发的新方法， 该系统适用于高分辨率光学显微镜、生化分析和基因抑制 使用RNAi。这些研究的结果将有助于对网络的基本了解， 在形态发生等过程中调节细胞形状变化的细胞成分 和细胞迁移。这项建议的目标是了解细胞形态发生的机制基础， 能动性细胞形状变化的正确执行对胚胎发育至关重要-如果 它们在发育过程中不同步，或者根本不发生，这可能导致先天性出生 缺陷就像明智的那样，细胞运动是伤口愈合和免疫等过程的基础 反应不适当的细胞运动也是动脉粥样硬化、炎症和炎症的潜在原因。 转移

The ability of cells to alter their shape is critical to the ontogeny of most organisms. Within tissues, for example, changes in cellular morphology drive tissue remodeling during morphogenesis and are essential for wound repair. At the level of the individual cell, cycles of shape change allow some cell types to migrate during embryogenesis, immune function, and (more insidiously) during metastasis. Cellular morphology is dictated by the cytoskeleton - the network of actin filaments and microtubules. The long-term goal of this project is to understand the principles and mechanisms underlying cellular morphology at the molecular level by studying the pathways that regulate and integrate cytoskeletal dynamics. Importantly, the networks of actin and microtubules do not act in isolation, rather there is an unprecedented degree of cross-talk, both regulatory interactions and mechanical interactions. Microtubule plus end-tracking proteins (or +TIPs) are a class of molecules that selectively localize to the tips of growing and shrinking microtubules. Since their discovery in 1999, +TIPs have been implicated in almost every microtubule-dependent cellular function including regulation of microtubule dynamic instability, organelle and chromosomal transport, assembly of the mitotic spindle, establishment of cellular polarity, and cell migration. In this proposal, we focus on +TIPs with a particular emphasis on actin-microtubule cross-talk as this represents a relatively unexplored functional interface between the two cytoskeletal networks. Our core hypothesis is that microtubule plus ends are dynamic platforms that deliver information to cortical regulatory networks governing cell shape and also act as sites of structural integration between actin and microtubules. We will test these ideas using novel assays we have developed with cultured Drosophila cell lines as this model system is amenable to high-resolution light microscopy, biochemical analyses, and gene inhibition using RNAi. The results of these studies will contribute to a basic understanding about the network of cellular components that mediate changes in cellular shape during processes such as morphogenesis and cell migration. The goal of this proposal is to understand the mechanistic basis of cellular morphogenesis and motility. The proper execution of cellular shape changes is essential for embryonic development - if they are not synchronized during development, or fail to occur at all, this can result in congenital birth defects. Like wise, cellular motility underlies processes such as wound healing and immune response. Improper cell motility is also an underlying cause of atherosclerosis, inflammation, and metastasis.