Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

Previous studies have demonstrated that phosphorylation of human p53 on serine 15 contributes to protein stabilization after DNA damage and that this is mediated by the ATM family of kinases. However, cellular exposure to hypoxia does not induce any detectable level of DNA lesions compared to ionizing radiation, and the oxygen dependency of p53 protein accumulation differs from that of HIF-1, the hypoxia-inducible transcription factor. Here we show that, under severe hypoxic conditions, p53 protein accumulates only in S phase and this accumulation correlates with replication arrest. Inhibition of ATR kinase activity substantially reduces hypoxia-induced phosphorylation of p53 protein on serine 15 as well as p53 protein accumulation. Thus, hypoxia-induced cell growth arrest is tightly linked to an ATR-signaling pathway that is required for p53 modification and accumulation. These studies indicate that the ATR kinase plays an important role during tumor development in responding to hypoxia-induced replication arrest, and hypoxic conditions could select for the loss of key components of ATR-dependent checkpoint controls.

Original publication




Journal article


Mol Cell Biol

Publication Date





1834 - 1843


Ataxia Telangiectasia Mutated Proteins, Cell Cycle Proteins, Cell Division, Cell Hypoxia, Cell Line, Cell Nucleus, Cobalt, Comet Assay, DNA Damage, DNA Replication, Enzyme Inhibitors, Humans, Hypoxia-Inducible Factor 1, alpha Subunit, Iron Chelating Agents, Oligonucleotide Array Sequence Analysis, Phosphorylation, Protein Serine-Threonine Kinases, S Phase, Signal Transduction, Stress, Physiological, Transcription Factors, Tumor Suppressor Protein p53