Quantitative Analysis and Modeling of Microtubule Structure and Regulation

描述（由申请人提供）：癌症的标志是不受控制的细胞分裂，许多癌症治疗措施通过破坏微管动力学和/或有丝分裂纺锤体结构来阻止细胞分裂。很明显，适当的微管组织和长度调节对于细胞分裂的成功完成是重要的。在这项研究中，我们将集中在微管相关蛋白如何在有丝分裂过程中调节微管长度和组织纺锤体微管的机制。为了为这些和未来的研究提供基础，我们将首先关注在没有调节蛋白的情况下的微管动力学，以更好地理解微管尖端结构和微管动力学之间的关系。我们的初步建模结果预测，微管尖端结构对于自我调节微管动力学非常重要。我们将使用体外荧光和电子显微镜以及芽殖酵母的体内分析来研究这一假设。然后，我们将研究尖端跟踪的重要微管加上末端结合蛋白，如Eb 1的机制，以确定微管尖端结构是否可以提供一个平台，重要的长度调节蛋白的微管尖端的目标。最后，我们将研究微管相关蛋白在细胞分裂过程中将微管组织成有丝分裂纺锤体的作用。具体而言，我们将使用在芽殖酵母细胞，体外重建，和计算机模拟的体内实验，以确定的作用和机制的驱动蛋白-14负端定向电机在建立正确的微管捆绑在有丝分裂纺锤体。

DESCRIPTION (provided by applicant): A hallmark of cancer is uncontrolled cell division, and many cancers therapeutic measures work by disrupting microtubule dynamics and/or mitotic spindle architecture to arrest cell division. It is clear that proper microtubule organization and length regulation are important for the successful completion of cell division. In this study, we will focus on mechanisms for how microtubule-associated proteins regulate microtubule lengths and organize spindle microtubules during mitosis. To provide a basis for these and future studies, we will first focus on microtubule dynamics in the absence of regulating proteins to better understand the relationship between microtubule tip structures and microtubule dynamics. Our preliminary modeling results predict that microtubule tip structures are important for self-regulating microtubule dynamics. We will investigate this hypothesis using in-vitro fluorescence and electron microscopy, as well as in-vivo analysis in budding yeast. Then, we will investigate the mechanism for tip-tracking of important microtubule plus end-binding proteins, such as Eb1, to determine whether the microtubule tip structures could provide a platform for targeting of important length-regulating proteins to the microtubule tip. Finally, we will investigate the role of microtubule- associated proteins in organizing microtubules into a mitotic spindle during cell division. Specifically, we will use in-vivo experiments in budding yeas cells, in-vitro reconstitution, and computer simulations to determine the role and mechanism of Kinesin-14 minus-end directed motors in establishing proper microtubule bundling in mitotic spindles.