Fig. 4: OFD1 depletion impairs BRCA1-mediated DNA damage response and repair efficiency.

a Schematic of the HR-GFP reporter for HRR efficiency. b Effect of OFD1 knockdown on HRR efficiency. GFP-positive cells were quantified by FACS 48 h after transfection. BRCA1 knockdown was used as a positive control. Data: mean values ± SD (n = 3 biologically independent experiments); unpaired two-tailed Student’s t test. c Impact of OFD1 knockdown on metaphase chromosome spread in the MIA PaCa-2 cells. Arrows indicate chromosomes with missing arms or chromosomal fusions. Scale bar = 50 μm. d Quantification of chromosomal abnormalities in the indicated groups (n > 20 metaphase spreads). Error bars represent mean values ± SD, unpaired two-tailed student’s t test. p = 1.11215E-11 Ctr vs shOFD1. e–g Representative Confocal images (e) and quantification of γH2AX(f) and BRCA1 (g) foci in MIA PaCa-2 cells with OFD1 knockdown or re-expression, ± 10 Gy IR. Scale bar, 10 μm. ≥ 20 fields per group analyzed. Data are mean ± SD; unpaired two-tailed Student’s t test. h, i Neutral comet assay in sh-Ctr, shOFD1, shOFD1 + OFD1 OE MIA PaCa-2 cells after treatment with 0 or 5 μM olaparib for 48 h. h Representative images of the comet assay. Scale bar = 25 μm. The tail moment was quantified using Image J (Open-Comet plugin) software. i Quantification of tail moment. Data are presented as mean values ± SD (n = 100 cells per group); unpaired two-tailed t test. The experiments were performed in triplicate. Source data are provided as a Source Data file.