Does maintenance of Polycomb Group proteins through DNA replication contribute to epigenetic inheritance?

Abstract

Epigenetic mechanisms maintain transcriptional programs through development and differentiation.  One class of epigenetic mechanisms is believed to involve assembly of heritable chromatin features at target genes.  These mechanisms require that chromatin structures can be propagated through DNA replication, but little is known about how chromatin structures can be maintained during or reformed after DNA replication.  Polycomb Group proteins maintain transcriptional repression using chromatin-based epigenetic mechanisms.  Our recent work suggests that some of these proteins can be inherited through DNA replication.  This result is discussed in light of general models for maintaining chromatin structures through DNA replication and previous studies of Polycomb Group protein-mediated gene silencing.