Figure 2.

Oxydative stress controls the cell proliferation of mouse MEF cells through the epigenetic regulation of the p16^Ink4a/Arf locus by JDP2. Young MEF primary cells exposed to oxidative stress (20%) accumulate JDP2. In the presence of JDP2, PRC1, and PRC2 dissociate from the p16^Ink4a/Arf locus, and histone H3 on the promoter is demethylated. Finally, p16^Ink4a and Arf are upregulated to express and then aged cells senescence. In the absence of JDP2, MEF cells do not enter the senescence stage and proliferate well. In the lower oxygen (3%), both WT and Jdp2^−/− MEF cells are not senesced but proliferated.