DNMT3A-dependent DNA methylation shapes the endothelial enhancer landscape

Area of Science:

• Epigenetics
• Molecular Biology
• Vascular Biology

Background:

• DNA methylation is vital for gene regulation during development.
• The role of DNA methylation in endothelial cell (EC) state transitions (angiogenic to quiescent) is not well understood.
• Understanding EC epigenetic regulation is key to vascular health.

Purpose of the Study:

• To investigate longitudinal changes in the DNA methylome of murine pulmonary vasculature.
• To identify the role of DNA methylation and DNMT3A in EC state transitions and aging.
• To elucidate the impact of DNA methylation on enhancer activity and transcriptome regulation in ECs.

Main Methods:

• Longitudinal DNA methylome analysis of murine pulmonary vasculature.
• Correlation of methylation patterns with endothelial gene expression.
• Motif enrichment analysis for DNA methyltransferase 3a (DNMT3A).
• Loss-of-function studies in mice to assess DNMT3A's role.

Main Results:

• Significant DNA methylation (hyper- and hypomethylation) changes occur during EC state transition.
• DNA methylation marks stabilize in quiescent ECs and remain stable during aging.
• DNMT3A is recruited to specific gene regions, and its absence impairs active enhancers and causes mild transcriptional changes.
• DNMT3A-dependent methylation influences the histone landscape for transcriptome regulation.

Conclusions:

• DNA methylation is a critical epigenetic mechanism governing EC function during state transitions.
• DNMT3A-dependent DNA methylation plays a key role in establishing and maintaining EC epigenetic states and enhancer integrity.
• Epigenetic regulation by DNA methylation is essential for accurate transcriptome regulation and vascular homeostasis.