N6-methyladenosine (m6A) modification regulates LONP1 to inhibit coxsackievirus B3 replication by suppressing virus-induced ferroptosis.

Coxsackievirus B3 (CVB3), a significant pathogen causing myocarditis and pancreatitis, lacks effective therapies due to unclear pathogenesis. This study reveals a novel role of N6-methyladenosine (m6A) RNA modification in regulating mitochondrial protease LONP1 during CVB3 infection. Using methylated RNA immunoprecipitation (MeRIP), we observed a significant reduction in LONP1 mRNA m6A levels post-CVB3 infection, correlating with upregulated LONP1 expression. Mechanistically, the 2B of CVB3 degraded the methyltransferase WTAP via the proteasome pathway, diminishing m6A deposition on LONP1's 3' UTR, as confirmed by dual-luciferase assays. Reduced m6A impaired YTHDF2-mediated mRNA decay, stabilizing LONP1 transcripts. Functionally, LONP1 overexpression inhibited CVB3 replication (evidenced by reduced VP1 protein and viral titers) and mitigated virus-induced ferroptosis by restoring glutathione peroxidase 4 and suppressing acyl-CoA synthetase long-chain family member 4, intracellular iron accumulation, and ROS overproduction. Conversely, LONP1 silencing exacerbated viral proliferation and ferroptotic damage. These findings establish LONP1 as an m6A-regulated antiviral factor that suppresses CVB3 replication via ferroptosis inhibition, highlighting the therapeutic potential of targeting m6A machinery (e.g., WTAP/YTHDF2) or LONP1-mediated mitochondrial homeostasis in enteroviral infections.