Figure 4.

H2B depletion is associated with abscission delay. CTRi and H2Bi HeLa cells were obtained as above and were followed through division by time-lapse microscopy. (a) Representative stills from time-lapse recording of HeLa CTRi and H2Bi cells. The time (in hrs:min) since the beginning of the round up is shown. Scale bar is 10 μm. The relative videos are Videos S1 and S2. CTRi cells divide and return mononucleated in about 3 h while H2Bi cells remain connected by intercellular bridge for several hours before abscission occurs. (b) The time from round up to cleavage furrow ingression was determined in CTRi HeLa cells (n = 150) and in H2Bi (n = 100). (c) The time from cleavage furrow ingression to abscission (abscission time) was determined in CTRi HeLa cells (n = 81) and in H2Bi (n = 107). In (b) and (c), the cumulative percentage of the analyzed cells from four independent transfections is plotted as function of time.