A combined AFM-Fluorescence experiment: adhesion proteins recruitment in response to a local and functional mechanical stimulus

C. VON BILDERLING; M. CALDAROLA; A. V. BRAGAS; L. I. PIETRASANTA

Carlos Paz, Córdoba.

Congreso; Reunión Anual de la Sociedad Argentina de Biofísica; 2013

Sociedad Argentina de Biofísica

Mechanical forces play an important role in the organization, growth, maturation and function of living tissues. At the cellular level, many of the biological responses to external forces originate at two types of specialized structures: focal adhesions and adherent junctions. In order to explore the dynamic regulation of adhesive contacts, we are focused on the relationship between local force applied to the cell and the assembly, mechanics and dynamics of focal adhesions (FA). The goal of our work is to study the dynamic response of FA proteins when a precise and local force is applied. In this context, we integrate Fluorescence Microscopy and Atomic Force Microscopy (AFM) in a new combined microscope to investigate the recruitment of adhesion proteins in response to an applied local and functional stimulus. With this novel combined microscope we studied the temporal evolution of the fluorescence from fusion GFP-FAs proteins (FAK, vinculin and zyxin), in response to the mechanical stimulus applied with a fibronectin functionalized AFM force-probe. We were able to observe the remodeling of mature FAs and the recruitment of FAK and vinculin to form nascent FAs in response to the locally applied nN forces.