Figure 7.

Unified Model of Chromatin Organization in Different Senescence Conditions

OIS leads to DNMT1 overexpression and a simultaneous release of SAHDs from the periphery. SAHDs decondense as they move away from periphery and gain inter-SAHD interactions to form SAHFs. Conversely, in RS conditions the SAHDs remain at the periphery with no major changes in inter- or intra-SAHD interactions. However, in cells undergoing OIS, DNMT1 knockdown leads to a partial rescue of SAHDs detachment from the lamin and prevents HMGA2 overexpression. These conditions prevent SAHF formation in DNMT1-depleted OIS nuclei, and the new chromatin architecture resembles the Replicative-Senescent state.