Figure 2.

DNA methylation landscape in induced-pluripotent stem cells (iPSCs) and directly converted neurons (iNs). Reprogramming of aged fibroblasts to the pluripotent cell stage is characterized by methylation erasure and reset of epigenetic clock. The epigenetic rejuvenation occurs before complete dedifferentiation to iPSCs, suggesting novel treatments for age-associated diseases. During this process, a large reconfiguration of DNA methylation leads to aberrant CH and CpG methylation in differentiated cells. iNs derived from aged fibroblasts bypass the intermediate pluripotent cell stage, but still lack a faithful CH DNA methylation and show an altered CpG hypermethylation pattern at promoter regions. OKSM (OCT4, KLF4, SOX2, C-MYC); BAM (ASCL1, BRN2, MYT1L).