Fig. 2. Cold shock and cell-cycle synchronization with XL413 improve HDR efficiency in iPS cells.

a Experimental timeline with no cold shock [A], and cold shock for 24 h [B] or 48 h [C] following electroporation (EP) on day 0 (left). EdU/PI staining was performed after 48 h of culture, and FACS analysis on day 8. The resulting effect on DNA repair outcome frequency is shown (right). b Ratio of HDR/MutEJ repair outcomes measured in a. c Representative FACS plots of EdU/PI staining (left) for quantification of cell-cycle phase (middle left) and mean EdU intensity of S-phase cells (middle right) 48 h after EP with no cold shock [A] or cold shock for 48 h [C] following EP. Schematic of the cell cycle showing cold shock arrest in G2/M phase (right). d Experimental timeline (left) of XL413-induced cell-cycle arrest for 24 h post-EP, in the absence [A] or presence [C] of cold shock. EdU/PI staining was performed after 24 h of culture, and FACS analysis on day 8. Repair outcomes were quantified in the absence or presence of XL413 (right). e Ratio of HDR/MutEJ repair outcomes measured in d. f Representative FACS plots of EdU/PI staining (left) 24 h after EP for untreated and XL413-treated cells under normal culture conditions [A], and quantification of cell-cycle phase (middle left) and mean EdU intensity of S-phase cells (middle right). Schematic of XL413-induced cell-cycle arrest in the G1/early S phase (right). All data are presented as the mean ± S.D. of three technical replicates for each respective treatment. Source data are provided as a Source Data file.