Illuminating Cell Adhesion: Modern Microscopy Approaches to Study Integrin-Based Focal Adhesions

Abstract

Integrin-based focal adhesions are plasma membrane-associated macromolecular structures that link the extracellular matrix to the cytoskeleton and play important roles in a variety of cellular processes. Focal adhesions dynamically change shape, size, and biochemical composition, all of which are carefully regulated by the cell to perform its function normally. Additionally, focal adhesions are also the primary conduits for relaying physical information between the cell and its environment. It is all these properties that make focal adhesions a unique research problem at the interface of biology and technology and have driven the development and application of many techniques to study them. In this article, we review how light and force microscopy-based approaches have expanded our understanding of integrin-based focal adhesions. We highlight specific questions about focal adhesions that each technique addresses, and the novel insight gained from studies using these approaches to understand how these complex adhesion organelles of more than 500 proteins are built and regulated, and the integration of the cell with its environment in mediating physiological functions.