MMP13 and Arthritis: Knocking out WTAP in chondrocytes decreased the m6A level (Fig. 3f) and significantly decreased the mRNA (ADAMTS4, ADAMTS5, MMP13, IL-6, IL-8, iNOS) and protein levels of arthritis-related genes (ADAMTS4, ADAMTS5, MMP13) in the OA cell model (Fig. 3g–i).