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DNA double-strand break repair: a theoretical framework and its application.

Murray PJ, Cornelissen B, Vallis KA, Chapman SJ - J R Soc Interface (2016)

Bottom Line: It has previously been shown that anti-γH2AX antibodies, modified by the addition of the cell-penetrating peptide TAT and a fluorescent or radionuclide label, can be used to visualize and quantify DSBs in vivo.Equations that describe stochastic mean behaviours at individual DSB sites are derived and parametrized using population-scale, time-series measurements from two different cancer cell lines.This work supports the conclusion that DSB kinetics are largely unaffected by the introduction of the anti-γH2AX antibody, a result that has been validated experimentally, and hence the hypothesis that the use of anti-γH2AX antibody to quantify DSBs does not violate the image tracer principle.

View Article: PubMed Central - PubMed

Affiliation: Division of Mathematics, University of Dundee, Dundee, UK pmurray@dundee.ac.uk.

No MeSH data available.


Related in: MedlinePlus

The average number of detectable γH2AX foci (, solid line) and γH2AX molecules (〈Z〉(t), dashed line) are plotted against time. (a) MDA-MB-468 and (b) and MCF7. Realizations of equation (2.1) were calculated using Gillespie's algorithm. Parameter values as in table 1. (Online version in colour.)
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RSIF20150679F5: The average number of detectable γH2AX foci (, solid line) and γH2AX molecules (〈Z〉(t), dashed line) are plotted against time. (a) MDA-MB-468 and (b) and MCF7. Realizations of equation (2.1) were calculated using Gillespie's algorithm. Parameter values as in table 1. (Online version in colour.)

Mentions: Both in the parametrization described in §3.2 and in previous studies, it has been assumed that the experimentally measured number of observable foci is proportional to the total number of γH2AX molecules counted across a number of NDSB foci and averaged over an ensemble of realizations [13]. The stochastic model is used to investigate this assumption as follows: in a given stochastic realization, we determine that a γH2AX focus is detectable under the microscope if the number of γH2AX molecules exceeds some threshold, Z*, and calculate the expected number of visible foci in a population of NDSB DSBs over an ensemble of realizations. In figure 5, we show, that for the parameter values chosen, the counted number of foci is proportional to the mean number of γH2AX molecules.Figure 5.


DNA double-strand break repair: a theoretical framework and its application.

Murray PJ, Cornelissen B, Vallis KA, Chapman SJ - J R Soc Interface (2016)

The average number of detectable γH2AX foci (, solid line) and γH2AX molecules (〈Z〉(t), dashed line) are plotted against time. (a) MDA-MB-468 and (b) and MCF7. Realizations of equation (2.1) were calculated using Gillespie's algorithm. Parameter values as in table 1. (Online version in colour.)
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4759787&req=5

RSIF20150679F5: The average number of detectable γH2AX foci (, solid line) and γH2AX molecules (〈Z〉(t), dashed line) are plotted against time. (a) MDA-MB-468 and (b) and MCF7. Realizations of equation (2.1) were calculated using Gillespie's algorithm. Parameter values as in table 1. (Online version in colour.)
Mentions: Both in the parametrization described in §3.2 and in previous studies, it has been assumed that the experimentally measured number of observable foci is proportional to the total number of γH2AX molecules counted across a number of NDSB foci and averaged over an ensemble of realizations [13]. The stochastic model is used to investigate this assumption as follows: in a given stochastic realization, we determine that a γH2AX focus is detectable under the microscope if the number of γH2AX molecules exceeds some threshold, Z*, and calculate the expected number of visible foci in a population of NDSB DSBs over an ensemble of realizations. In figure 5, we show, that for the parameter values chosen, the counted number of foci is proportional to the mean number of γH2AX molecules.Figure 5.

Bottom Line: It has previously been shown that anti-γH2AX antibodies, modified by the addition of the cell-penetrating peptide TAT and a fluorescent or radionuclide label, can be used to visualize and quantify DSBs in vivo.Equations that describe stochastic mean behaviours at individual DSB sites are derived and parametrized using population-scale, time-series measurements from two different cancer cell lines.This work supports the conclusion that DSB kinetics are largely unaffected by the introduction of the anti-γH2AX antibody, a result that has been validated experimentally, and hence the hypothesis that the use of anti-γH2AX antibody to quantify DSBs does not violate the image tracer principle.

View Article: PubMed Central - PubMed

Affiliation: Division of Mathematics, University of Dundee, Dundee, UK pmurray@dundee.ac.uk.

No MeSH data available.


Related in: MedlinePlus