These proteins are required for long term epigenetic silencing of chromatin and have an important role in stem cell differentiation and early embryonic development.
[3] PRC2 has a role in X chromosome inactivation, in maintenance of stem cell fate,[4] and in imprinting.
[5] Polycomb group genes directly and indirectly regulate the DNA damage response which acts as an anti-cancer barrier.
In Arabidopsis thaliana, a plant model organism, several variants of the core subunits have been identified.
Homologs of the Suz12 subunit are: Embryonic flower 2 (EMF2), reduced vernalization response 2 (VRN2), fertilization independent seed 2 (FIS2).