A model of Tet1-mediated chromocenter clustering in DNA hypomethylated cells.
CpG sites in the PCH were highly methylated by DNMTs and not accessible by TET1 and PcG proteins in the wild-type ESCs (Left panel). DNA hypomethylated condition allows TET1 to bind PCH region and TET1 recruits PcG proteins in the Dnmt1-KO ESCs. Thus, 5hmC, H2AK119ub, and H3K27me3 are enriched in PCH, and the chromocenters are clustered through the LLPS mechanism (Middle panel). PcG proteins are not recruited to PCH and chromocenters remain dispersed in the Dnmt1/Tet1-KO ESCs (Right panel).