Figure 4
Upregulation of MMP-13 expression by nuclear Hic-5 in human chondrocytes. (A) Induction of MMP-13 in human chondrocytes exogenously expressing Hic-5 tagged with a nuclear localization signal (NLS-HA-Hic-5). Human chondrocytes were transfected with the NLS-HA-Hic-5 expression vector at the concentrations shown in the graph for 24 h. Hic-5 and MMP-13 expression was measured by quantitative polymerase chain reaction (n = 3 biological replicates). (B) Western blot of MMP-13 in human chondrocytes transfected with or without 0.2 µg of NLS-Hic-5 (n = 3 biological replicates). Values are the mean ± SEM. **P < 0.01 by the Kruskal–Wallis test, followed by Dunn’s multiple comparisons test in (A) or the unpaired t test in (B). Western blotting images were cropped, and full-length blots are included in Supplementary Fig. 1. (C) Double immunofluorescence staining of Hic-5 (green) and MMP-13 (red) in human chondrocytes transfected with or without NLS-HA-Hic-5. Nuclei were counterstained with DAPI (blue). Representative image was selected from 3 biological replicates. Original magnification: × 400. Bar = 50 μm.
