Severe fever with thrombocytopenia syndrome virus induces lactylation of m6A reader protein YTHDF1 to facilitate viral replication

EMBO Rep. 2024 Dec;25(12):5599-5619. doi: 10.1038/s44319-024-00310-7. Epub 2024 Nov 4.

Abstract

Severe fever with thrombocytopenia syndrome virus (SFTSV), an emerging infectious pathogen with a high fatality rate, is an enveloped tripartite segmented single-stranded negative-sense RNA virus. SFTSV infection is characterized by suppressed host innate immunity, proinflammatory cytokine storm, failure of B-cell immunity, and robust viral replication. m6A modification has been shown to play a role in viral infections. However, interactions between m6A modification and SFTSV infection remain poorly understood. Through MeRIP-seq, we identify m6A modifications on SFTSV RNA. We show that YTHDF1 can bind to m6A modification sites on SFTSV, decreasing the stability of SFTSV RNA and reducing the translation efficiency of SFTSV proteins. The SFTSV virulence factor NSs increases lactylation of YTHDF1 and YTHDF1 degradation, thus facilitating SFTSV replication. Our findings indicate that the SFTSV protein NSs induce lactylation to inhibit YTHDF1 as a countermeasure to host's YTHDF1-mediated degradation of m6A-marked viral mRNAs.

Keywords: Lactylation; Post-translational Modifications (PTMs); SFTSV; YTHDF1; m6A.

MeSH terms

  • HEK293 Cells
  • Host-Pathogen Interactions
  • Humans
  • Phlebovirus* / genetics
  • Phlebovirus* / metabolism
  • Phlebovirus* / physiology
  • RNA, Viral / genetics
  • RNA, Viral / metabolism
  • RNA-Binding Proteins* / genetics
  • RNA-Binding Proteins* / metabolism
  • Severe Fever with Thrombocytopenia Syndrome* / metabolism
  • Severe Fever with Thrombocytopenia Syndrome* / virology
  • Viral Nonstructural Proteins / genetics
  • Viral Nonstructural Proteins / metabolism
  • Virus Replication*

Substances

  • RNA-Binding Proteins
  • YTHDF1 protein, human
  • RNA, Viral
  • Viral Nonstructural Proteins