Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Comment
. 2006:2:2006.0032.
doi: 10.1038/msb4100060. Epub 2006 Jun 13.

Another turn for p53

John J Tyson
Comment

Another turn for p53

John J Tyson. Mol Syst Biol. 2006.
No abstract available

PubMed Disclaimer

Figures

Figure 1
Figure 1
p53 protein level rises in response to DNA damage and triggers three responses.
Figure 2
Figure 2
Small perturbations (blue zone) away from the stable steady state (red dot) are immediately damped out (short arrows), but larger perturbations, beyond the threshold (dashed line), generate transient activation of p53. What do you expect will happen if this p53–Mdm2 control system is continually buffeted by stochastic fluctuations?
Figure 3
Figure 3
Two types of bifurcations to limit cycle oscillations: Hopf (red) and homoclinic (blue). ‘Signal' is some ‘input parameter' to the control system. ‘Response' is some ‘output variable' governed by the control system. At signal=0, the control system is sitting at a stable steady state (bold solid line) with low level of response. As signal increases, the steady state loses stability at a bifurcation point (vertical dashed line). Beyond the bifurcation point, the steady state is unstable (bold dashed line) and the system oscillates between maximal and minimal response values (red and blue dotted curves). Typical oscillations at two different signal strengths (a and b) are illustrated in the middle panel. If the signal strength is fluctuating between a and b, the Hopf bifurcation is expected to give an oscillating response of roughly constant period and highly variable amplitude (far right). The homoclinic bifurcation, by contrast, is expected to give an oscillating response of roughly constant amplitude and highly variable period.
See this image and copyright information in PMC

Comment on

  • Oscillations and variability in the p53 system.
    Geva-Zatorsky N, Rosenfeld N, Itzkovitz S, Milo R, Sigal A, Dekel E, Yarnitzky T, Liron Y, Polak P, Lahav G, Alon U. Geva-Zatorsky N, et al. Mol Syst Biol. 2006;2:2006.0033. doi: 10.1038/msb4100068. Epub 2006 Jun 13. Mol Syst Biol. 2006. PMID: 16773083 Free PMC article.

References

    1. Ciliberto A, Novak B, Tyson JJ (2005) Steady states and oscillations in the p53/Mdm2 network. Cell Cycle 4: 488–493 - PubMed
    1. Geva-Zatorsky N, Rosenfeld N, Itzkovitz S, Milo R, Sigal A, Dekel E, Yarnitzky T, Polak P, Liron Y, Kam Z, Lahav G, Alon U (2006) Oscillations and variability in the p53 system. Mol Syst Biol 2006.0033. doi:10.1038/msb4100068 - PMC - PubMed
    1. Hanahan D, Weinberg RA (2000) The hallmarks of cancer. Cell 100: 57–70 - PubMed
    1. Lahav G, Rosenfeld N, Sigal A, Geva-Zatorsky N, Levine AJ, Elowitz MB, Alon U (2004) Dynamics of the p53–Mdm2 feedback loop in individual cells. Nat Genet 36: 147–150 - PubMed
    1. Lev Bar-Or R, Maya R, Segel LA, Alon U, Levine AJ, Oren M (2000) Generation of oscillations by the p53–Mdm2 feedback loop: a theoretical and experimental study. Proc Natl Acad Sci USA 97: 11250–11255 - PMC - PubMed

MeSH terms

Substances

LinkOut - more resources