Figure 1
MMP14 expression in degradative focal adhesions in RPE cells. (A,B) Representative images of ARPE19 plated on a fluorescein-conjugated gelatin coverslip for 5 hours and immunostained with anti-vinculin (in A) or anti-MMP14 (in B) antibodies followed by Alexa 568-secondary antibodies. Black-and-white single-channel images and the merged color images are shown. Enlarged views are from the boxed areas showing the overlapping vinculin signal and degradation foci. (C) Representative low-power (insets) and high-power images of ARPE19 cells plated on non-fluorescent gelatin-coated coverslips for 5 hours and labeled for MMP14 (green) and vinculin (red). (D,E) ARPE19 cells transfected with MMP14-mCherry for one day were plated on fluorescein-conjugated gelatin coverslips for 5 hours. Both low-power (D) and high-power (E) views are shown. Arrows in (D) point to the cells with massive gelatin degradation activity caused by the ectopic expression of MMP14-mCherry. Arrows in (E) point to the MMP14-mCherry-labeled tubulovesicles that match the gelatin degradation footprints. (F) Representative images of ARPE19 cells plated on non-coated coverslips and immunostained for endogenous MMP14 (green) and CD63 (red). Blue (in A,B,D–F): DAPI nuclear stain. Scale bars (in A–F) = 10 µm.
