Fig. 6: PFN1 binds BOD1L and suppresses its fork-protective activity.

a Representative PLA images for the interaction between HA-PFN1 and endogenous BOD1L in HeLa cells. Scale bar, 5 µm. b Quantitative analysis of HA-PFN1/BOD1L PLA in (a) based on foci number per nucleus (>5 considered positive), and percentages of PLA-positive nuclei out of around 300 DAPI-positive total cells analyzed, as described in (1c and 2 f). c DNA fiber analysis of dual-labeled PFN1-overexpressing HeLa cells transfected with control or BOD1L siRNAs, as in (1e–j). d, e Ratios of CIdU/IdU tract lengths in dual-labeled and subsequently HU-treated (2 mM, 2 h) MCF-10A cells overexpressing PFN1 and transfected with control or siRNAs targeting BOD1L, BRCA1, or BRCA2, as described in Fig. 4a–c. In (c–e), at least 300 fibers were analyzed per condition. f, g PLA analysis between endogenous BOD1L and biotinylated EdU in PFN1-overexpressing (f) or PFN1 knockdown/rescue (g) MCF-10A cells treated or not with HU (2 mM in f and 4 mM in g) for 2 h. The numbers of PLA foci per nucleus were quantified. Data are mean ± SEM of around 100 PLA-positive cells per condition. h Representative PLA images for f, g. Scale bar, 5 µm. Kruskal–Wallis test with Dunnett’s multiple comparisons was used for all statistical analyses. **p < 0.01; ***p < 0.001; ****p < 0.0001; ns, not significant. All results were confirmed by at least two independent experiments.