Inheritance of chromatin modifications through the cell cycle
Following mitosis, the particular transcriptional landscape of the parent cell must be faithfully transmitted to daughter cells. Although transcription ceases, not all transcription factors are displaced. DNA methylation has been implicated in the inheritance of chromatin characteristics because maintenance DNA methyl transferases methylate CpG dinucleotides on the newly replicated strand if the corresponding GpC on the parent strand is methylated. Nucleosomes that are deposited on the newly synthesized DNA strands are made up of old and new histones, and some marks present on the old histones are maintained. The proper distribution of nucleosomes and the topological organization of the genome into topologically associating domains (TADs) must be transmitted to daughter cells. Following DNA replication, centromeres must be specified on the daughter chromatids. In most eukaryotes, centromeres are identified by the presence of nucleosomes bearing the histone H3 variant CENP-A. An additional number of proteins and non-coding RNAs originating from centric and pericentromeric DNA repeats associate with centromeres and appear to play a role in centromere function.