Although how PABPC4 exhibits an antiviral effect and how HIV-1 infection downregulates PABPC4 remain unclear, these findings suggest that HIV-1 may counteract PABPC4-mediated antiviral action by downregulating this gene through the formation of the ribonucleoprotein complex of viral proteins and PABPC4. Here, PABPC4 is linked to HIV-1 infection.