Repression of SMAD3 by STAT3 and c-Ski induces conventional dendritic cell differentiation

Life Sci Alliance. 2024 Jul 3;7(9):e201900581. doi: 10.26508/lsa.201900581. Print 2024 Sep.

Abstract

A pleiotropic immunoregulatory cytokine, TGF-β, signals via the receptor-regulated SMADs: SMAD2 and SMAD3, which are constitutively expressed in normal cells. Here, we show that selective repression of SMAD3 induces cDC differentiation from the CD115+ common DC progenitor (CDP). SMAD3 was expressed in haematopoietic cells including the macrophage DC progenitor. However, SMAD3 was specifically down-regulated in CD115+ CDPs, SiglecH- pre-DCs, and cDCs, whereas SMAD2 remained constitutive. SMAD3-deficient mice showed a significant increase in cDCs, SiglecH- pre-DCs, and CD115+ CDPs compared with the littermate control. SMAD3 repressed the mRNA expression of FLT3 and the cDC-related genes: IRF4 and ID2. We found that one of the SMAD transcriptional corepressors, c-SKI, cooperated with phosphorylated STAT3 at Y705 and S727 to repress the transcription of SMAD3 to induce cDC differentiation. These data indicate that STAT3 and c-Ski induce cDC differentiation by repressing SMAD3: the repressor of the cDC-related genes during the developmental stage between the macrophage DC progenitor and CD115+ CDP.

MeSH terms

  • Animals
  • Cell Differentiation*
  • DNA-Binding Proteins* / metabolism
  • Dendritic Cells* / cytology
  • Dendritic Cells* / metabolism
  • Inhibitor of Differentiation Protein 2 / genetics
  • Inhibitor of Differentiation Protein 2 / metabolism
  • Interferon Regulatory Factors / genetics
  • Interferon Regulatory Factors / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Phosphorylation
  • Proto-Oncogene Proteins* / genetics
  • Proto-Oncogene Proteins* / metabolism
  • STAT3 Transcription Factor* / genetics
  • STAT3 Transcription Factor* / metabolism
  • Signal Transduction
  • Smad2 Protein / genetics
  • Smad2 Protein / metabolism
  • Smad3 Protein* / genetics
  • Smad3 Protein* / metabolism
  • fms-Like Tyrosine Kinase 3 / genetics
  • fms-Like Tyrosine Kinase 3 / metabolism

Substances

  • Flt3 protein, mouse
  • fms-Like Tyrosine Kinase 3
  • Idb2 protein, mouse
  • Inhibitor of Differentiation Protein 2
  • interferon regulatory factor-4
  • Interferon Regulatory Factors
  • Proto-Oncogene Proteins
  • Smad2 Protein
  • Smad2 protein, mouse
  • Smad3 Protein
  • Smad3 protein, mouse
  • Stat3 protein, mouse
  • STAT3 Transcription Factor
  • Ski protein, mouse
  • DNA-Binding Proteins