Table 1.

Distribution of tracks with C1dU-only, IdU-only, or containing both labels

% of Fibers AnalyzedExperiments
% IdU-Only (Premature Terminations)% CldU-Only (New Origin Firing)% IdU-C1dU conjoined tracks (Fork Elongation)
wt
    Not treated40%11%49%n = 5
    H20238%6%56%n = 5
FEN1−/−
    Not treated32%24%38%n = 2
    H2O268%4%25%n = 2

NOTE: Cells were pulsed with IdU, treated with H202 and then pulsed with C1dU before preparing the DNA fibers. The numbers of tracks with C1dU-only (green-only, second pulse), IdU-only (red-only, first pulse), or both (conjoined/red-green) were counted and converted to a percentage of total scored. At least 150 intermediates were counted per experimental condition and per repeat.