MKL1 is an epigenetic mediator of TNF-α-induced proinflammatory transcription in macrophages by interacting with ASH2

FEBS Lett. 2017 Mar;591(6):934-945. doi: 10.1002/1873-3468.12601. Epub 2017 Mar 8.

Abstract

Tumor necrosis factor alpha (TNF-α) is a prototypical proinflammatory cytokine that can elicit strong inflammation in macrophages by activating NF-κB. The underlying epigenetic mechanism is obscure. We show here that megakaryocytic leukemia 1 (MKL1) is an epigenetic mediator of TNF-α-induced proinflammatory transcription. Overexpression of a dominant negative form of MKL1 abrogates TNF-α-induced transactivation of proinflammatory genes. Proteomic analysis identifies the histone H3K4 trimethyltransferase ASH2 as a potential cofactor for MKL1. In response to TNF-α stimulation, ASH2 is recruited by MKL1 and interacts with MKL1 to catalyze H3K4 di- and trimethylation. ASH2 modulates proinflammatory transcription at least in part by altering the affinity of p65 for target promoters. Together, our data support an interplay between MKL1 and ASH2 to promote TNF-α-induced proinflammatory transcription in macrophages.

Keywords: ASH2; MKL1; TNF-α; epigenetics; macrophage; transcriptional regulation.

MeSH terms

  • Adult
  • Amino Acid Sequence
  • Animals
  • Cell Line
  • Cell Line, Tumor
  • Cells, Cultured
  • Cytokines / genetics
  • Cytokines / metabolism
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / metabolism
  • Electrophoresis, Polyacrylamide Gel
  • Epigenesis, Genetic
  • Gene Expression Regulation / drug effects
  • HEK293 Cells
  • Histones / metabolism
  • Humans
  • Inflammation Mediators / metabolism
  • Lysine / metabolism
  • Macrophages / drug effects*
  • Macrophages / metabolism
  • Male
  • Methylation
  • Mice, Knockout
  • NF-kappa B / metabolism
  • Nuclear Proteins / genetics*
  • Nuclear Proteins / metabolism
  • Protein Binding
  • Reverse Transcriptase Polymerase Chain Reaction
  • Trans-Activators / genetics*
  • Trans-Activators / metabolism
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism
  • Tumor Necrosis Factor-alpha / genetics
  • Tumor Necrosis Factor-alpha / pharmacology*

Substances

  • ASH2L protein, human
  • Cytokines
  • DNA-Binding Proteins
  • Histones
  • Inflammation Mediators
  • MRTFA protein, human
  • NF-kappa B
  • Nuclear Proteins
  • Trans-Activators
  • Transcription Factors
  • Tumor Necrosis Factor-alpha
  • Lysine