Although previous studies indicate that loss of p53-mediated cell cycle arrest, apoptosis, and senescence does not completely abrogate its tumor suppression function, it is unclear how the remaining activities of p53 are regulated. Here, we have identified an acetylation site at lysine K98 in mouse p53 (or K101 for human p53). Whereas the loss of K98 acetylation (p53K98R) alone has very modest effects on p53-mediated transactivation, simultaneous mutations at all four acetylation sites (p534KR: K98R+ 3KR[K117R+K161R+K162R]) completely abolish its ability to regulate metabolic targets, such as TIGAR and SLC7A11. Notably, in contrast to p533KR, p534KR is severely defective in suppressing tumor growth in mouse xenograft models. Moreover, p534KR is still capable of inducing the p53-Mdm2 feedback loop, but p53-dependent ferroptotic responses are markedly abrogated. Together, these data indicate the critical role of p53 acetylation in ferroptotic responses and its remaining tumor suppression activity.
Bibliographical noteFunding Information:
This work was supported by the National Cancer Institute of the NIH under award 5RO1CA172023, 5RO1CA190477, and 5RO1CA085533 to W.G. and RO1GM105933 and RO1GM115961 to Y.Z. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.
© 2016 The Authors
- metabolic regulation
- tumor suppression