The histone reader PHF7 cooperates with the SWI/SNF complex at cardiac super enhancers to promote direct reprogramming

Nat Cell Biol. 2021 May;23(5):467-475. doi: 10.1038/s41556-021-00668-z. Epub 2021 May 3.

Abstract

Direct cardiac reprogramming of fibroblasts to cardiomyocytes presents an attractive therapeutic strategy to restore cardiac function following injury. Cardiac reprogramming was initially achieved through overexpression of the transcription factors Gata4, Mef2c and Tbx5; later, Hand2 and Akt1 were found to further enhance this process1-5. Yet, staunch epigenetic barriers severely limit the ability of these cocktails to reprogramme adult fibroblasts6,7. We undertook a screen of mammalian gene regulatory factors to discover novel regulators of cardiac reprogramming in adult fibroblasts and identified the histone reader PHF7 as the most potent activating factor8. Mechanistically, PHF7 localizes to cardiac super enhancers in fibroblasts, and through cooperation with the SWI/SNF complex, it increases chromatin accessibility and transcription factor binding at these sites. Furthermore, PHF7 recruits cardiac transcription factors to activate a positive transcriptional autoregulatory circuit in reprogramming. Importantly, PHF7 achieves efficient reprogramming in the absence of Gata4. Here, we highlight the underexplored necessity of cardiac epigenetic readers, such as PHF7, in harnessing chromatin remodelling and transcriptional complexes to overcome critical barriers to direct cardiac reprogramming.

Publication types

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

MeSH terms

  • Animals
  • Cellular Reprogramming
  • Fibroblasts / metabolism
  • GATA4 Transcription Factor / genetics
  • GATA4 Transcription Factor / metabolism*
  • Histones / metabolism*
  • Myocytes, Cardiac / metabolism
  • Proto-Oncogene Proteins c-akt / metabolism
  • Regulatory Sequences, Nucleic Acid / physiology
  • Signal Transduction / physiology*
  • Transcription Factors / metabolism
  • Ubiquitin-Protein Ligases / genetics
  • Ubiquitin-Protein Ligases / metabolism*

Substances

  • GATA4 Transcription Factor
  • Gata4 protein, mouse
  • Histones
  • Transcription Factors
  • Phf7 protein, mouse
  • Ubiquitin-Protein Ligases
  • AKT1 protein, human
  • Proto-Oncogene Proteins c-akt