Figure 4.

FNIII9 and FNIII10 are necessary for attenuation of PDGF-induced intracellular calcium release. FN-null MEFs were seeded on collagen-coated wells (1.1 × 10⁵ cells/cm²). Four hours after seeding, cells were treated with the indicated fibronectin fusion proteins (250 nM) and incubated for 20 h. Cells were loaded with Fluo-4, stimulated with 30 ng/mL PDGF, and monitored for changes in fluorescence intensity. Data are presented as relative change in fluorescence intensity from baseline (ΔF/F₀) and are expressed as mean ± SEM of 8 (A,B) or 5 (C) experiments performed in quadruplicate. Values were normalized to the “+GST” condition, which was set to 1. * Significantly different versus +GST by ANOVA (p < 0.05).