Self-clustering of three CBX2 molecules drives PRC2 to promote facultative heterochromatinization of Polycomb target genes - PubMed
4 days ago
- #phase-separation
- #CBX2
- #PRC2
- Self-clustering of three CBX2 molecules drives PRC2 to promote facultative heterochromatinization of Polycomb target genes.
- Single-molecule imaging shows condensates in mESCs contain ~3 CBX2 molecules and PRC1/PRC2 subunits, with composition regulated developmentally.
- CBX2 clusters PRC2 and controls spatial distribution of PRC2 and H3K27me3.
- CBX2 binds to condensate initiation sites enriched for PRC2 nucleation sites.
- CBX2 deletion redistributes PRC2 and H3K27me3 from regular targets.
- A separation-of-function variant confirms CBX2's self-clustering ability is essential for its function.
- Supports a phase-separation model driven by nucleation and bridging, where low-abundance proteins self-cluster to initiate condensate assembly.