• ¹Medical Research Institute, College of Life Sciences, Wuhan University, Wuhan 430072, China.
• ²State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430072, China.
• ³Medical Research Institute, College of Life Sciences, Wuhan University, Wuhan 430072, China. Electronic address: shuh@whu.edu.cn.
• ⁴State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430072, China. Electronic address: wangyy@wh.iov.cn.

ViralDNAsensing within the cytosol of infected cells activates type I interferon (IFN) expression.MITA/STING plays an essential role in this pathway by acting as both a sensor for the second messenger cGAMP and as an adaptor for downstreamsignalingcomponents. In an expression screen for proteins that can activate the IFNB1 promoter, we identified theER-associatedproteinZDHHC1as apositiveregulatorofvirus-triggered,MITA/STING-dependentimmunesignaling.Zdhhc1(-/-) cells failed to effectively produce IFNs and other cytokines in response to infection withDNAbut not RNA viruses.Zdhhc1(-/-) mice infected with the neurotropicDNAvirus HSV-1 exhibited lower cytokine levels and higher virus titers in the brain, resulting in higher lethality.ZDHHC1constitutively associated withMITA/STING and mediates dimerization/aggregation ofMITA/STING and recruitment of the downstreamsignalingcomponents TBK1 and IRF3. These findings support a role forZDHHC1in mediatingMITA/STING-dependentinnateimmuneresponse againstDNAviruses.