Automated Cell Cycle Analysis Figure 7. TSA detects changes in interphase duration in response to doxorubicin treatment. HeLa H2B-GFP cells were treated with doxorubicin at indicated concentrations. Cells were imaged every 12 min for 48 hours. For each condition, 4 fields in 2 independent wells were imaged and the results for the 8 image series were combined. Image series were analyzed using DCELLIQ with TSA. Cumulative frequency curves of interphase (a) and mitotic (b) durations for the cell populations are provided. doi:10.1371/journal.pone.0025511.g007 mitosis, or the mitotic division will not be detected. In principle, imaging at this frequency could produce phototoxicity, especially when cells are imaged for a long period of time. However, published studies that have described phototoxicity associated with long-term imaging used much longer exposures, much greater intensity, and/or more frequent illumination compared to our PLoS ONE | www.plosone.org 9 September 2011 | Volume 6 | Issue 9 | e25511