DNA replication

During replication the epigenetic marks on nucleosomes are distributed equally to the two daughter duplexes (Gan et al, 2018; Petryk et al., 2018; Yu et al., 2018). Displacement of nucleosomes by FACT (facilitates chromatin transcription) enables replisome progression through chromatinized DNA (Gambus et al., 2006; Kurat et al., 2017). The general view is that the H3H4 tetramer, which carries the bulk of epigenetic marks, binds DNA tightly and is transferred to nascent DNA independent of H2AH2B dimers that are easily displaced and exchanged (Alabert et al., 2017). Two binding sites for H3H4 exist in the replisome: The N-terminal region of Mcm2 binds H3H4 (Huang et al., 2015; Richet et al., 2015), and 2) the Dpb3/4 subunits of Pol e bind H3H4 at the C-face of CMG (Bellelli et al., 2018; Tackett et al., 2005; Sun et al, 2015). Recent studies have found specific roles of these replisome H3H4 sites in