Resetting histone modifications during human parental Biology Diagrams The histone modifications are lowest at the LS cell-cycle phase (Figure 2E, late on bottom), consistent with chromatin mark dilution during replication. Genomic regions in the blue H3K27me3-enriched state ( Figure 2 F, histone modification heatmap) have a wide range of temporal changes coordinated between histone methylation marks, chromatin
López-Hernández et al. review how transcription, replication, and repair shape complex patterns of histone modifications on chromatin, processes that must be collectively interpreted for proper genome function. In this model, histone modifications initiate, maintain, and record interactions between different DNA processes, facilitating communication between them. It is thus often challenging to quantitatively compare histone modification ChIP-seq data sets from different phases of the cell cycle. To overcome this, we used a spike-in based normalization strategy, whereby adding an equal amount of exogenous chromatin from a different species into each sample can be used as a more accurate normalization For example, repression of the cell-cycle-dependent cyclin E gene by the retinoblastoma gene product RB involves recruitment of HDACs, Here, we describe the known histone modifications, define
How the cell cycle impacts chromatin architecture and ... Biology Diagrams
Accumulation of reverse centromeric transcripts is still cell-cycle dependent in cells lacking Dicer, consistent with an involvement of the exosome at the end of S phase . The exosome affects the turnover of other S-phase-specific transcripts, such as histone transcripts in Saccharomyces cerevisiae , perhaps by a similar mechanism [11,12] . Histone lysine acetylation (Kac) is a classical histone acylation that has an effect related to DNA damage and repair, cell-cycle control, chromatin architecture, RNA splicing, and transcription . Methylation takes part in gene repression or activation, depending on the sites and degree [ 14 , 15 ]. We highlight recent advances in understanding cell cycle-dependent histone biogenesis and histone modification deposition, how cell cycle regulators control histone modifier activities, the contribution of chromatin modifications to origin firing for DNA replication, and newly identified roles for nucleoporins in regulating cell cycle gene
Here we use cell cycle sorting and ChIP-seq to analyse the genomic distribution of three histone modifications closely associated with transcriptional regulation (H3K9ac, H3K4me3 and H3K27me3