DNA methylation disruption reshapes the hematopoietic differentiation landscape

Area of Science:

• Hematology
• Epigenetics
• Molecular Biology

Background:

• Mutations in DNA methylation genes like TET2 and DNMT3A are common in blood cancers and clonal hematopoiesis.
• These mutations are known to affect hematopoietic stem and progenitor cells.

Purpose of the Study:

• To investigate how DNA methylation gene mutations disrupt hematopoietic differentiation.
• To understand the mechanisms linking genome-wide DNA methylation changes to specific progenitor cell biases.

Main Methods:

• Single-cell sequencing of murine hematopoietic stem and progenitor cells.
• Analysis of transcriptional priming in uncommitted hematopoietic stem cells.
• Targeted genotyping of human clonal hematopoiesis bone marrow progenitors.

Main Results:

• Tet2 or Dnmt3a loss caused opposing shifts in erythroid and myelomonocytic progenitor frequencies.
• These differentiation shifts originated from transcriptional priming biases in hematopoietic stem cells.
• Differential sensitivity of transcription factors to CpG enrichment in binding motifs explains the observed skews.

Conclusions:

• DNA methylation plays a critical role in shaping hematopoietic differentiation pathways.
• A model is proposed where genome-wide methylation changes influence differentiation through transcription factor binding site biases.