Alyref Deficiency Exacerbates Chronic Inflammatory Pain by Impairing m5C-Dependent Nuclear Export of Ccn3 mRNA

Here, we investigated the role of the m⁵C reader Alyref in a mouse model of complete Freund’s adjuvant (CFA)-induced chronic inflammatory pain. We observed a marked and sustained upregulation of Alyref in nociceptive neurons of the dorsal root ganglion (DRG) following CFA administration.

Conditional deletion of Alyref in NaV1.8⁺ nociceptive neurons significantly exacerbated thermal and cold hypersensitivity, mechanical allodynia, and hyperalgesia. These behavioral abnormalities were accompanied by pronounced activation of microglia and astrocytes in the spinal dorsal horn, along with elevated expression of proinflammatory mediators, indicating enhanced neuroinflammation and central sensitization. Mechanistically, Alyref directly binds to m⁵C-modified Ccn3 mRNA and promotes its nuclear export, thereby maintaining cytoplasmic Ccn3 expression in DRG neurons.