The interplay shows that preventing UBE2N loss preserves mitophagy and halts harmful NRF2-driven PANoptosis, emphasizing mitochondria quality control as central to disease mitigation.

UBE2N acts as a master switch in metabolic dysfunction-associated steatohepatitis (MASH), determining whether liver cells repair themselves or undergo inflammatory cell death.

Its protective effect hinges on two linked processes: mitophagy via the PARKIN pathway with K63-ubiquitination of p62/SQSTM1 at lysine 420, and the suppression of PANoptosis to prevent inflammatory cell death.

Without UBE2N, mitophagy collapses and PANoptosis drives inflammatory damage; cytoplasmic p62 buildup further fuels NRF2 hyperactivation, which paradoxically promotes cell death when excessive.

Therapeutically, targeting UBE2N or the p62 trafficking pathway could restore mitochondrial quality control and curb NRF2-driven PANoptosis, offering a new treatment axis beyond lipid metabolism for MASH.

Genetic removal of Sqstm1 (p62) in UBE2N-deficient livers reduces disease severity, confirming cytoplasmic p62 accumulation as a key damaging driver and identifying p62 trafficking as a potential therapeutic target.

THAP11 represses UBE2N transcription under metabolic stress, diminishing K63-linked ubiquitination essential for signaling and mitophagy in hepatocytes.

In hepatocytes, loss of UBE2N worsens MASH and liver fibrosis on a Western-style diet, while restoring UBE2N reverses pathology, indicating a protective role.

Findings come from human liver tissue and mouse models, showing UBE2N downregulation, hepatocyte-specific Ube2n knockout causality, and rescue with hepatic overexpression, supported by single-nucleus RNA sequencing and spatial transcriptomics.

NRF2’s role in this context challenges the belief that it is universally protective in liver disease, highlighting the need for balanced redox signaling in MASH.

Overall, the study identifies UBE2N- and p62-driven mitophagy pathways as a compelling new target for interventions in the global liver disease epidemic.