Skip to main content
. Author manuscript; available in PMC: 2009 Jul 3.
Published in final edited form as: Oncogene. 2008 Mar 10;27(29):4065–4074. doi: 10.1038/onc.2008.48

Figure 9. Model of p21-dependent cell cycle arrest during oxidative stress.

Figure 9

Oxidative stress and damage sequentially activates hSMG-1 and ATM to phosphorylate and activate p53-dependent transcription of p21. Active hSMG-1 and ATM also stimulate p53-independent proteolysis of p21 via the proteasome. Levels of p21 are ultimately dictated by PIKKs controlling p53-dependent synthesis versus p53-independent proteolysis of p21.