H4K20me3 methyltransferase SUV420H2 shapes the chromatin landscape of pluripotent embryonic stem cells
ABSTRACT Heterochromatin, a densely packed chromatin state that is transcriptionally silent, is a critical regulator of gene expression. However, it is unclear how the repressive histone modification H4K20me3 or the histone methyltransferase SUV420H2 regulates embryonic stem (ES) cell fate by patterning the epigenetic landscape. Here, we report that depletion of SUV420H2 leads to a near complete loss of H4K20me3 genome wide, dysregulated gene expression and delayed ES cell differentiation. SUV420H2 bound regions are enriched with repetitive DNA elements, which are de repressed in SUV420H2 knockout ES cells. Moreover, SUV420H2 regulation of H4K20me3 marked heterochromatin controls chromatin architecture, including fine scale chromatin interactions in pluripotent ES cells. Our results indicate that SUV420H2 plays a crucial role in stabilizing the three dimensional chromatin landscape of ES cells, as loss of SUV420H2 resulted in A/B compartment switching, perturbed chromatin insulation, and altered chromatin interactions of pericentric heterochromatin and surrounding regions, indicative of localized decondensation. In addition, depletion of SUV420H2 resulted in compromised interactions between H4K20me3 and gene regulatory regions. Together, these findings describe a new role for SUV420H2 in regulating the chromatin landscape of ES cells. Summary: SUV420H2 regulation of H4K20me3 marked heterochromatin controls the chromatin structure of embryonic stem cells, where loss of SUV420H2 results in dysregulated gene expression and differentiation, altered 3D chromatin interactions, compartment switching and perturbed chromatin insulation.
Development