c-NHEJ pathway is indispensable for DMSR. (A) DMSR was examined when cells were treated with DNA-PK, ATM, or ATR inhibitors. Quantitation of microtubule length is shown (n > 50). (B) DMSR was examined in cells with depletion of indicated genes. Quantitation of microtubule length is shown (n > 50). Cells were transfected with an equal amount of scrambled siRNA as an NC. (C) 53BP1 regulated DMSR. DMSR was examined in cells with depletion of indicated genes. Quantitation of microtubule length is shown (n > 50). (D) Depletion of Ligase 4, XRCC4, or XLF increases the extent of DMSR. Quantitation of microtubule length is shown (n > 50). (E) Depletion of Ligase 4 prolongs the time course of DMSR. Quantitation of microtubule length is shown (n > 50). (F) Box plot shows quantitative analysis of GFP-EB3 comet velocity in live siRNA-treated GFP-EB3–expressing G1 RPE-1 cells (n > 30). (G) Centrosome-dependent microtubule nucleation capacity was determined by relative centrosomal GFP-EB3 intensity in live siRNA-treated GFP-EB3–expressing G1 RPE-1 cells, and quantitative analysis is shown in box plot (n > 30). ****, P < 0.0001; ***, P < 0.001; **, P < 0.01; *, P < 0.05; ns, not significant. A.U., arbitrary units; MT, microtubule; UT, untreated.