Grant: CIHR New Investigator

A single cell division can herald the beginning of life or portend the development of a devastating disease such as cancer. With each division, all animal cells must partition genetic material correctly into the future daughter cells. To do this, the cell first replicates its genetic material and then builds a complex 3D structure to physically separate the duplicated genetic material. This structure is called the mitotic spindle and it is largely composed of long rigid tube-like polymers termed microtubules. In addition to forming the mitotic spindle, microtubules give cells their shape, they help cells move, and they provide a scaffold for the transport of proteins to and from the outer reaches of the cell. How does a simple polymer provide all of these functions within a cell? The simple answer is that the cell contains many proteins that serve as cellular architects, regulating when and where microtubules form. In ways that we do not understand, the microtubule regulators work together to coordinate the assembly and disassembly of microtubules at specific intracellular locations in a timely manner. In order to better understand the regulation of microtubules in the cell, we are using molecular genetics to identify proteins required for microtubule-based processes such as mitotic spindle assembly. With specialized microscopy assays, we can further characterize the role of the regulatory proteins by determining if they instruct microtubules to grow, shrink, or move. For example, one molecular pathway we are studying is implicated in controlling the stability of microtubules in the mitotic spindle, and another project focuses on understanding how the mitotic spindle is positioned by nano-scale motors that pull on microtubules. Knowledge gained from these studies will help us understand how cells control microtubules during cell division. It could also provide new approaches to interfere with microtubule function as a way to halt renegade cell division in cancer.