Research

Motion is fundamental to life. Everyone is familiar with the movement we generate with our muscles. There are also exquisite, essential motions taking place at the level of cells and molecules. The cells in our immune system crawl around our bodies and engulf invading bacteria. Cilia in our lungs beat to remove inhaled debris. Vesicles are transported across neurons in our brains, spinal chords, and limbs. In all cases, the motion is generated by tiny protein machines, the molecular motors.

Work in my lab aims to understand how these protein machines convert chemical energy into mechanical work, and how their activities are regulated. State-of-the-art optical trapping and fluorescence microscopy techniques are used to manipulate the individual motors, to apply force to them, and to measure the nanometer-scale motions they generate. Tools from molecular biology and biochemistry are also used, to purify the proteins and organelles, and to modify the proteins in specific ways.

A major focus is the mitotic spindle, an exquisite molecular machine that organizes and separates duplicated chromosomes during cell division, thereby ensuring equal partitioning of the genetic material. By reconstituting spindle functions with purified components, and applying biophysical tools for manipulating and tracking of individual molecules, we are uncovering how this machine operates.