FCLs and RAs presence correlates with FN production in multiple cells lines. (A–E) The following knock-in cell lines were used in this figure: U2Os-AP2-GFP, HeLa-AP2-GFP, hMEC-AP2-GFP, U2Os-AP2-halo, HeLa-AP2-halo, MCF7-AP2-halo, HDF-AP2-halo, and Caco2-AP2-halo. (A) Cell lines indicated were plated to non-coated (nc) dishes, allowed to settle overnight, and stained for integrin αvβ5 and FN. Representative TIRF images. (B) Analysis of FN fluorescent intensity from samples in A. N (images): U2Os = 21, HeLa = 20, MCF7 = 23, HDF = 33, Caco2 = 16, hMEC = 23, from two independent experiments. F(5, 130) = 56.16, P < 0.0001. (C) Cells were plated on FN-coated or nc dishes, allowed to settle overnight, and stained for integrin αvβ5 and p-Pax. Representative TIRF images. (D) Analysis of RA coverage from samples in C. Cell lines with an AP2 halo tag, n (images): U2Os (nc/FN) = 20, HeLa (nc) = 33, HeLa (FN) = 29, MCF7 (nc) = 29, MCF7 (FN) = 32, HDF (nc/FN) 32, Caco2 (nc/FN) = 32. Data were obtained from two individual experiments and similar results were observed in four individual experiments. F(9, 273) = 64.96, P < 0.0001. (E) Analysis of RA coverage from samples in C. Cell lines with an AP2 GFP tag, n (images): U2Os (nc) = 31, U2Os (FN) = 18, HeLa (nc) = 35, HeLa (FN) = 38, and hMEC (nc/FN) = 38. Data were obtained from two individual experiments and similar results were observed in four individual experiments. F(5, 189) = 89.97, P < 0.0001. (F) A schematic illustration of the results shown in this figure. Data are the mean ± SD, ns. non-significant P value; *** P value < 0.001. Scale bars, 10 µm.