Figure 5. Bipolar localization of PopZ... | Rockefeller University Press

Figure 5.

$Figure 5. Bipolar localization of PopZ can happen in the absence of DNA replication. (A) CJW2214 cells were grown in liquid medium with xylose to induce the expression of YFP-PopZ. Swarmer cells were treated or not treated with 25 µg/ml novobiocin and imaged every 30 min. The mean fraction of cells showing bipolar YFP-PopZ localization (from three independent experiments per condition) is shown for each time point. Error bars show SEM. (B) Representative cells from one experiment described in A are shown for each time point, under untreated and novobiocin-treated conditions. Arrows point at bipolar YFP-PopZ foci. (C) CFP-ParB was imaged at each time point in the same cells as in A. The mean fraction of cells having two CFP-ParB foci (from three independent experiments per condition) is shown for each time point. Error bars show SEM. (D) Swarmer CJW4721 cells were grown on an M2G agarose pad containing 5 µg/ml novobiocin. The fraction of cells with two PopZ-YFP foci or with at least one DnaN-mCherry focus (indicative of DNA replication) is shown for each time point. Outlines and fluorescent signals of representative cells at 150 min after synchrony are shown. Arrowheads point at bipolar PopZ-YFP. (E) Swarmer CJW2237 cells were grown on an M2G agarose pad containing 5 µg/ml novobiocin. Shown are kymographs of the PopZ-YFP and CFP-ParB signals along the cell length over time from two representative cells. Relative positions of 0 and 1 represent the old pole and the new pole, respectively. Note that C. crescentus grows slower on agarose pads (E) than in liquid cultures (as in A). Bars, 2 µm.$

Bipolar localization of PopZ can happen in the absence of DNA replication. (A) CJW2214 cells were grown in liquid medium with xylose to induce the expression of YFP-PopZ. Swarmer cells were treated or not treated with 25 µg/ml novobiocin and imaged every 30 min. The mean fraction of cells showing bipolar YFP-PopZ localization (from three independent experiments per condition) is shown for each time point. Error bars show SEM. (B) Representative cells from one experiment described in A are shown for each time point, under untreated and novobiocin-treated conditions. Arrows point at bipolar YFP-PopZ foci. (C) CFP-ParB was imaged at each time point in the same cells as in A. The mean fraction of cells having two CFP-ParB foci (from three independent experiments per condition) is shown for each time point. Error bars show SEM. (D) Swarmer CJW4721 cells were grown on an M2G agarose pad containing 5 µg/ml novobiocin. The fraction of cells with two PopZ-YFP foci or with at least one DnaN-mCherry focus (indicative of DNA replication) is shown for each time point. Outlines and fluorescent signals of representative cells at 150 min after synchrony are shown. Arrowheads point at bipolar PopZ-YFP. (E) Swarmer CJW2237 cells were grown on an M2G agarose pad containing 5 µg/ml novobiocin. Shown are kymographs of the PopZ-YFP and CFP-ParB signals along the cell length over time from two representative cells. Relative positions of 0 and 1 represent the old pole and the new pole, respectively. Note that C. crescentus grows slower on agarose pads (E) than in liquid cultures (as in A). Bars, 2 µm.