Fig. 4

CircFTO inhibits the expression of SOX9 in an m6A-dependent manner. (A) Multiple potential m6A modification sites were predicted in the 3’UTR of SOX9 using SRAMP. (B) The level of m6A-modified SOX9 was assessed in chondrocytes through m6A RIP assay. (C) The impact of circFTO overexpression or knockdown on the m6A modification of SOX9 3’UTR was investigated. (D) The effect of circFTO overexpression or knockdown on the expression of SOX9 mRNA was examined. (E) The expression levels of WTAP, METTL3, and METTL14 were evaluated in chondrocytes following simultaneous knockdown of WTAP, METTL3, and METTL14. (F) The expression level of SOX9 was measured in chondrocytes after the indicated treatment. (G-H) The relative remaining amount of SOX9 mRNA in chondrocytes was quantified at different time points upon treatment with actinomycin D (5 µg/mL). (I) The influence of specific exosomes on the m6A modification status within the 3’UTR region of SOX9 was determined. (J) The effect of specific exosomes on the expression level of SOX9 was investigated. Data are presented as mean ± SD, n = 3; ***p < 0.001, ##p < 0.01