Semaphorin 3A Increases FAK Phosphorylation at Focal Adhesions to Modulate MDA-MB-231 Cell Migration and Spreading on Different Substratum Concentrations

Figure 3

Sema3A increases cell spreading on low and intermediate coating concentrations of collagen and fibronectin but inhibits spreading at high coating concentrations of collagen and fibronectin. (a) Representative images of cells attached to substrata coated with low (1.0 μg/mL), intermediate (10 μg/mL), and high (100 μg/mL) concentrations of collagen that were stained using TRITC-phalloidin. Scale bar = 20 μm. Average area of cells exposed to increasing substratum concentrations of collagen (b), fibronectin (c), and laminin (d). Sema3A enhanced cell spreading at lower coating concentrations of collagen and fibronectin but inhibited spreading at high coating concentrations of collagen and fibronectin. Sema3A inhibited spreading at various coating concentrations of laminin but did not have any stimulatory effect on cell spreading. Data are presented as average cell area ± SEM from a minimum of 100 cells for each condition. , , and indicate statistical significance relative to IgG1 Fc control; two-sample -test.

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