question: Is H4K20 methylation associated with DNA replication?
answer: We employed genetic, cytological, and genomic approaches to better understand the role of PR-Set7 and H4K20 methylation in regulating DNA replication and genome stability in Drosophila cells. Thus, coordinating the status of H4K20 methylation is pivotal for the proper selection of DNA replication origins in higher eukaryotes. The methylation state of lysine 20 on histone H4 (H4K20) has been linked to chromatin compaction, transcription, DNA repair and DNA replication. Histone turnover is often associated with various histone modifications such as H3K56 acetylation (H3K56Ac), H3K36 methylation (H3K36me), and H4K20 methylation (H4K20me). We review the signaling pathways and functions associated with a single residue, H4K20, as a model chromatin and clinically important mark that regulates biological processes ranging from the DNA damage response and DNA replication to gene expression and silencing. <CopyrightInformation>© 2016 by The American Society for Biochemistry and Molecular Biology, Inc.</C In particular, the methylation states of H3K4, H3K36 and H4K20 have been associated with establishing active, repressed or poised origins depending on the timing and extent of methylation. 5BrC and 5ClC may cause aberrant methylation of cytosine during DNA replication and mimic the endogenous methylation signal associated with gene silencing.