Cell Reports (May 2023)

Glutamylation of an HIV-1 protein inhibits the immune response by hijacking STING

  • Gui Qian,
  • Yihua Zhang,
  • Yinan Liu,
  • Manman Li,
  • Bowen Xin,
  • Wenyi Jiang,
  • Wendong Han,
  • Yu Wang,
  • Xian Tang,
  • Liuyan Li,
  • Lingyan Zhu,
  • Tao Sun,
  • Bo Yan,
  • Yongtang Zheng,
  • Jianqing Xu,
  • Baoxue Ge,
  • Zheng Zhang,
  • Dapeng Yan

Journal volume & issue
Vol. 42, no. 5
p. 112442

Abstract

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Summary: Cyclic GMP-AMP synthase (cGAS) recognizes Y-form cDNA of human immunodeficiency virus type 1 (HIV-1) and initiates antiviral immune response through cGAS-stimulator of interferon genes (STING)-TBK1-IRF3-type I interferon (IFN-I) signalingcascade. Here, we report that the HIV-1 p6 protein suppresses HIV-1-stimulated expression of IFN-I and promotes immune evasion. Mechanistically, the glutamylated p6 at residue Glu6 inhibits the interaction between STING and tripartite motif protein 32 (TRIM32) or autocrine motility factor receptor (AMFR). This subsequently suppresses the K27- and K63-linked polyubiquitination of STING at K337, therefore inhibiting STING activation, whereas mutation of the Glu6 residue partially reverses the inhibitory effect. However, CoCl2, an agonist of cytosolic carboxypeptidases (CCPs), counteracts the glutamylation of p6 at the Glu6 residue and inhibits HIV-1 immune evasion. These findings reveal a mechanism through which an HIV-1 protein mediates immune evasion and provides a therapeutic drug candidate to treat HIV-1 infection.

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