Roles of TRIM32 in Corneal Epithelial Cells After Infection with Herpes Simplex Virus

Cell Physiol Biochem. 2017;43(2):801-811. doi: 10.1159/000481563. Epub 2017 Sep 28.

Abstract

Background: Epithelial cells play important roles as a critical barrier in protecting the cornea from microbial pathogens infection.

Methods: In this study, we were aiming to investigate the role of E3 ubiquitin ligase tripartite motif protein 32 (TRIM32) in corneal epithelial cells in response to Herpes Simplex Virus type 1 (HSV-1) infection and to elucidate the underlying mechanisms.

Results: We found the expression of TRIM32 was increased after infected with HSV-1 both in murine corneas and cultured human epithelial (HCE) cells. Furthermore, knockdown of the expression of TRIM32 significantly aggravated HSV-1 induced herpetic stromal keratitis (HSK) in mice and promoted the replication of HSV-1 in cultured HCE cells. We also observed that silencing of TRIM32 resulted in the decreased expression of IFN-β and suppressed activation of interferon regulatory factor 3 (IRF3) both in vivo and in vitro. Finally, we found TRIM32 positively regulate IFN-β production in corneal epithelial cells through promoting K63-linked polyubiquitination of stimulator of interferon genes (STING).

Conclusion: In conclusion, our data suggested that TRIM32 as a crucial positive regulator of HSV-1 induced IFN-β production in corneal epithelial cells, and it played a predominant role in clearing HSV-1 from the cornea.

Keywords: Corneal epithelial cells; Herpes Simplex Virus; In vitro; In vivo; Trim32.

MeSH terms

  • Animals
  • Cell Line
  • Cornea / metabolism
  • Cornea / pathology
  • Cornea / virology*
  • Down-Regulation
  • Female
  • Herpesvirus 1, Human / physiology*
  • Humans
  • Interferon Regulatory Factor-3 / metabolism
  • Interferon-beta / genetics
  • Interferon-beta / metabolism
  • Keratitis, Herpetic / genetics
  • Keratitis, Herpetic / metabolism*
  • Keratitis, Herpetic / pathology
  • Membrane Proteins / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Polyubiquitin / metabolism
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*
  • Tripartite Motif Proteins / genetics
  • Tripartite Motif Proteins / metabolism*
  • Ubiquitin-Protein Ligases / genetics
  • Ubiquitin-Protein Ligases / metabolism*
  • Up-Regulation

Substances

  • Interferon Regulatory Factor-3
  • Membrane Proteins
  • Sting1 protein, mouse
  • Transcription Factors
  • Tripartite Motif Proteins
  • Polyubiquitin
  • Interferon-beta
  • TRIM32 protein, human
  • TRIM32 protein, mouse
  • Ubiquitin-Protein Ligases