DNA hypomethylation leads to cGAS-induced autoinflammation in the epidermis

EMBO J. 2021 Nov 15;40(22):e108234. doi: 10.15252/embj.2021108234. Epub 2021 Sep 29.

Abstract

DNA methylation is a fundamental epigenetic modification, important across biological processes. The maintenance methyltransferase DNMT1 is essential for lineage differentiation during development, but its functions in tissue homeostasis are incompletely understood. We show that epidermis-specific DNMT1 deletion severely disrupts epidermal structure and homeostasis, initiating a massive innate immune response and infiltration of immune cells. Mechanistically, DNA hypomethylation in keratinocytes triggered transposon derepression, mitotic defects, and formation of micronuclei. DNA release into the cytosol of DNMT1-deficient keratinocytes activated signaling through cGAS and STING, thus triggering inflammation. Our findings show that disruption of a key epigenetic mark directly impacts immune and tissue homeostasis, and potentially impacts our understanding of autoinflammatory diseases and cancer immunotherapy.

Keywords: DNA methylation; autoinflammation; cytosolic DNA; epigenetics; innate immune system.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing / metabolism
  • Animals
  • Chromosome Aberrations
  • Cytosol / physiology
  • DNA (Cytosine-5-)-Methyltransferase 1 / genetics
  • DNA Methylation*
  • Dermatitis / genetics*
  • Dermatitis / immunology
  • Dermatitis / pathology
  • Epidermis / physiopathology*
  • Humans
  • Immunity, Innate / genetics
  • Interferon-Induced Helicase, IFIH1 / metabolism
  • Keratinocytes / immunology
  • Keratinocytes / metabolism
  • Keratinocytes / pathology
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism
  • Mice, Transgenic
  • Nucleotidyltransferases / genetics
  • Nucleotidyltransferases / metabolism*

Substances

  • Adaptor Proteins, Signal Transducing
  • IPS-1 protein, mouse
  • Membrane Proteins
  • Sting1 protein, mouse
  • DNA (Cytosine-5-)-Methyltransferase 1
  • Dnmt1 protein, mouse
  • Nucleotidyltransferases
  • cGAS protein, mouse
  • Ifih1 protein, mouse
  • Interferon-Induced Helicase, IFIH1

Associated data

  • GEO/GSE166356