Fibrinogen anchors enables the subcellular micropatterning of endogenous receptors. (A) Experimental scheme. Serum-starved HeLa cells were allowed to spread on dual micropatterns of fibronectin/fibrinogen-Alexa546 and fibrinogen-biotin-ATTO490LS::NeutrAvidin/biotin-EGF, then fixed and processed for immunofluorescence against EGFR and clathrin. (B) Efficient relocalization of the EGFR onto the active EGF micropattern. Note that clathrin is also recruited onto the micropattern. (C) Quantification of the effects seen in D (mean ± SEM). (D) Experimental scheme. U2OS cells stably expressing GFP-Notch1 were allowed to spread on dual micropatterns of fibronectin/fibrinogen-Alexa647 and fibrinogen-biotin-ATTO490LS::NeutrAvidin::biotin-DLL4 and imaged live 20 min later. (E) Efficient relocalization of GFP-Notch1 onto the active DLL4 micropattern. (F) Quantification of the effects seen in E (mean ± SEM). All statistics in this figure were performed using Student’s t tests. n, number of cells analyzed. Scale bar, 10 µm. Ctrl, control.