Nucleosome plasticity during the cell cycle

Nucleosome organization and dynamics play a central role in controlling the DNA accessibility to regulatory factors of many critical cellular functions, especially gene regulation. However, despite extensive studies, the main factors determining nucleosome positioning and its fluctuation during cell cycle still remain elusive. Here, we present a large-scale study of nucleosome plasticity throughout the cell cycle and its interplay with gene expression based on genome-wide nucleosome positioning and mRNA abundance. We have clusterized distinct nucleosome architectures around transcription start sites and replication origins and studied their dynamics during the cell cycle progression. The most significant cell cycle-dependent changes occur at G1-S and G2-M transitions due to a large changes in gene expression in cell cycle regulatory genes. Taken together, our accurate study provides a dynamic picture of chromatin organization along cell cycle and its interplay with gene expression.

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