Kinesin Motors and Microtubule-based Trafficking

项目摘要/摘要： 微管对真核细胞的几乎所有功能都是至关重要的，从它们分裂和移动的能力到 它们具有采用特定形态和抵抗机械力的能力。微管组装，动力学， 而功能受大量细胞因子的支配和调节，包括与微管相关的 运动蛋白和动力蛋白超家族中的蛋白质(MAP)和分子马达。我们的总体目标是定义 微管和动力蛋白驱动哺乳动物细胞内转运的机制 细胞。为了做到这一点，我们结合了强大的生物物理和生化方法，提供了机械细节 关于运动力学和运动性，用细胞分析来报告复合体内的调节和功能 蜂窝环境。我们将继续利用这些多学科方法来调查关键差距。 我们对细胞内运输的机制和调控的了解。我们将定义以下机制 蛋白质靶向初级纤毛，这是一个基于微管的细胞器，从细胞表面伸出 并驱动细胞运动和信号传递。我们将利用我们开发的一种新的化学遗传学方法 为工程可抑制马达探索对组装和功能至关重要的运动蛋白的功能 初级纤毛。我们将在体外和体外两种情况下确定运动蛋白的运动性和力生成特性 细胞分析，并利用这一知识来理解这些特性是如何通过进化来选择的 细胞中特定的运动功能。最后，我们将通过以下信号通路测试运动调节模型 刺猬配基。由于微管和运动蛋白马达的缺陷与发育障碍有关， 神经退行性疾病和癌症，这些研究将促进我们对它们在细胞中的功能的理解 生物学和疾病。

Project Summary/Abstract: Microtubules are critical for nearly every function of eukaryotic cells, from their ability to divide and move to their ability to adopt specific morphologies and withstand mechanical forces. Microtubule assembly, dyamics, and functions are dictated and regulated by a large number of cellular factors including microtubule associated proteins (MAPs) and molecular motors in the kinesin and dynein superfamilies. Our overall goal is to define the mechanisms by which microtubules and kinesin motor proteins drive intracellular trafficking in mammalian cells. To do this, we combine powerful biophysical and biochemical methods that provide mechanistic detail on motor mechanics and motility with cellular assays that report on regulation and function within the complex cellular environment. We will continue to utilize these multi-disciplinary approaches to investigate critical gaps in our knowledge of mechanisms and regulation of intracellular trafficking. We will define mechanisms for targeting of proteins to the primary cilium, a microtubule-based organelle that protrudes from the surface of the cell and drives cell motility and signaling. We will utilize a novel chemical-genetic approach that we developed for engineering inhibitable motors to probe the functions of kinesins critical for the assembly and function of primary cilia. We will determine the motility and force-generating properties of kinesins using both in vitro and cellular assays and use this knowledge to understand how these properties were selected through evolution for specific motor functions in cells. Finally, we will test models of motor regulation by signaling pathways such as Hedgehog ligand. As defects in microtubules and kinesin motors are linked to developmental disorders, neurodegenerative diseases, and cancer, these studies will advance our understanding of their functions in cell biology and disease.