title: Stimulated single-cell force spectroscopy to quantify cell adhesion receptor crosstalk.
abstract: To control their attachment to substrates and other cells, cells regulate their adhesion receptors. One regulatory process is receptor crosstalk, where the binding of one type of cell adhesion molecule influences the activity of another type. To identify such crosstalk and gain insight into their mechanisms, we developed the stimulated single-cell force spectroscopy assay. In this assay, the influence of a cells adhesion to one substrate on the strength of its adhesion to a second substrate is examined. The assay quantifies the adhesion of the cell and the contributions of specific adhesion receptors. This allows mechanisms by which the adhesion is regulated to be determined. Using the assay we identified crosstalk between collagen-binding integrin alpha(1)beta(1) and fibronectin-binding integrin alpha(5)beta(1) in HeLa cells. This crosstalk was unidirectional, from integrin alpha(1)beta(1) to integrin alpha(5)beta(1), and functioned by regulating the endocytosis of integrin alpha(5)beta(1). The single-cell assay should be expandable for the screening and quantification of crosstalk between various cell adhesion molecules and other cell surface receptors.
authors.affiliation: Biotechnology Center, University of Technology Dresden, Dresden, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Friedrichs
authors.forename: Jonne
authors.initials: J
authors.lastname: Helenius
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Müller
mesh_terms: D002448:Cell Adhesion / Q000502:physiology*; D003094:Collagen / Q000378:metabolism; D004705:Endocytosis; D005353:Fibronectins / Q000378:metabolism; D005434:Flow Cytometry; D006367:HeLa Cells; D006801:Humans; D039222:Integrin alpha1beta1 / Q000378:metabolism*; D039081:Integrin alpha5beta1 / Q000378:metabolism*; D018625:Microscopy, Atomic Force / Q000379:methods*; D020239:Receptor Cross-Talk / Q000502:physiology*; D015398:Signal Transduction
chemical_list: D005353:Fibronectins; D039222:Integrin alpha1beta1; D039081:Integrin alpha5beta1; D003094:Collagen