TP53 and neoplasm: p53S389A knock-in mice was produced and studies have shown that serine 389 phosphorylation selectively promotes apoptosis and tumor suppression under ultraviolet irradiation.358 p53S312A knock-in mice was generated and at this site, ES cells play a key role in the Nanog inhibition and ES cell differentiation, suggesting that serine 315 phosphorylation also plays a role in stem cells.359 Mouse p53 C-terminal contains many lysine residues (K367, K369, K370, K378, K379, K383, and K384), which can be modified by ubiquitination, acetylation, diacylation, sumoyation, or methylation.