Fig. 3: Runx1 regulated FTO gene transcriptional activity during OA progression.

a Venn diagram showing the overlaps between transcription factors predicted by JASPAR and two OA-related databases, GSE98918 and GSE206848. b mRNA expression levels of FTO and RUNX1 in mouse chondrocytes treated with siRNAs targeting RUNX1. c Western blot detection of FTO and RUNX1 expression in mouse chondrocytes treated with siRNAs targeting RUNX1. d mRNA expression levels of FTO and RUNX1 on days 1, 3, and 5 of cell culture in mouse chondrocytes. e Luciferase activity detection of HEK293T cells transfected with RUNX1 (or vector) and the FTO reporter. f Five primer pairs designed on the basis of the prediction of JASPAR. g ChIP analysis of five sites on the FTO promoter in mouse chondrocytes transfected with RUNX1 or IgG. h Luciferase activity detection of HEK293T cells transfected with the FTO reporter or the FTO mut reporter. i Safranin O/Fast Green staining and immunohistochemistry (RUNX1) of undamaged and damaged regions from the lateral and medial tibial plateaus of OA patients. n = 8. Scale bar, 100 μm and 20 μm. j Safranin O/Fast Green staining and immunohistochemistry (RUNX1) of the knee joints of the mice that underwent DMM surgery or the sham group. n = 8 per group. Scale bars, 100 μm and 20 μm. k Five databases for RUNX1 knockdown; the data are representative of three independent experiments (c). *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001, mean ± SD, two-tailed t test.