Studying Nanoscale Mechanics of Single Molecules and Cells with Atomic Force Microscopy

Abstract

This talk will present non-invasive mechanical approaches to high-resolution biological imaging developed in our group. We have demonstrated atomic force microscopy based imaging of chemical groups within protein complexes with Angstrom scale resolution and determined physiologically relevant intracellular forces in adherent cells. These approaches rely on sensitive measurements of tip-sample forces in liquid environment, and take advantage of the information encoded in force distance curves that can be chemically specific. In particular, the high-resolution cell stiffness images we obtained on mouse fibroblasts allowed us to develop and test a mechanical model of the cell that suggests that nanoscale stiffness patterns of cells are directly governed by intracellular forces. These patterns can be used to determined intracellular forces like cortex tension, plasma membrane tension, and the tension across actin filament bundles.