Expression of APOBEC2 is transcriptionally regulated by NF‐κB in human hepatocytes

Apolipoprotein B mRNA‐editing enzyme catalytic subunit 2 (APOBEC2) is a member of the nucleic‐acid‐editing enzymes. However, the physiological function of APOBEC2 remains unclear. We demonstrate that APOBEC2 expression is strongly enhanced in response to both tumour necrosis factor‐α (TNF‐α) and interleukin‐1β. Inhibition of NF‐κB activation invariably blocks TNF‐α‐induced APOBEC2 expression. The promoter region of APOBEC2 contains functional NF‐κB response elements in the 5′ untranslated region of the gene at −625/−616. These results show that APOBEC2 expression is regulated by pro‐inflammatory cytokines via NF‐κB activation and suggest a possible role of APOBEC2 in the pathophysiology of hepatic inflammation.

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