The Chd4 subunit of the NuRD complex regulates Pdx1-controlled genes involved in β-cell function

J Mol Endocrinol. 2022 Jun 14;69(2):329-341. doi: 10.1530/JME-22-0011.

Abstract

Type 2 diabetes (T2D) is associated with loss of transcription factors (TFs) from a subset of failing β-cells. Among these TFs is Pdx1, which controls the expression of numerous genes involved in maintaining β-cell function and identity. Pdx1 activity is modulated by transcriptional coregulators and has recently been shown, through an unbiased screen, to interact with the Chd4 ATPase subunit of the nucleosome remodeling and deacetylase complex. Chd4 contributes to the maintenance of cellular identity and functional status of numerous different cell types. Here, we demonstrated that Pdx1 dynamically interacts with Chd4 under physiological and stimulatory conditions within islet β-cells and established a fundamental role for Chd4 in regulating insulin secretion and modulating numerous Pdx1-bound genes in vitro, including the MafA TF, where we discovered Chd4 is bound to the MafA region 3 enhancer. Furthermore, we found that Pdx1:Chd4 interactions are significantly compromised in islet β-cells under metabolically induced stress in vivo and in human donor tissues with T2D. Our findings establish a fundamental role for Chd4 in regulating insulin secretion and modulating Pdx1-bound genes in vitro, and disruption of Pdx1:Chd4 interactions coincides with β-cell dysfunction associated with T2D.

Keywords: Chd4; beta cell; coregulator; insulin secretion; transcription factor; type 2 diabetes.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Diabetes Mellitus, Type 2* / genetics
  • Diabetes Mellitus, Type 2* / metabolism
  • Homeodomain Proteins / metabolism
  • Humans
  • Insulin-Secreting Cells* / metabolism
  • Mi-2 Nucleosome Remodeling and Deacetylase Complex / genetics
  • Mi-2 Nucleosome Remodeling and Deacetylase Complex / metabolism
  • Trans-Activators / metabolism
  • Transcription Factors / genetics
  • Transcription Factors / metabolism

Substances

  • CHD4 protein, human
  • Homeodomain Proteins
  • Trans-Activators
  • Transcription Factors
  • pancreatic and duodenal homeobox 1 protein
  • Mi-2 Nucleosome Remodeling and Deacetylase Complex