Extended Data Fig. 8: NUMEN participates in compartmentalized NHEJ repair at the nuclear periphery.

a, HEK293T cells stably expressing the 53BP1_trunc–mApple DSB reporter (red) together with NUMEN–GFP (green) were cultured with zeocin (100 μg ml⁻¹) in a glass-bottomed dish before time-lapse live-cell imaging. 53BP1trunc–mApple is a fusion protein of truncated 53BP1 and the Apple fluorescent protein. Images were captured every 3 min during a 4-h window, and those from the indicated time points are shown. Each boxed region is enlarged in the zoom panel (bottom). Arrows point to 53BP1_trunc–mApple signals that moved closer to NUMEN–GFP signals over time. b, The 53BP1_trunc–mApple DSB reporter cells described above were treated with 2 Gy IR and visualized by time-lapse live-cell imaging. Images were captured every 3 min during a 2-h window. c, GFP-tagged m⁶A-Tracer and Dam-LaminB1–mAmetrine co-expression HEK293T cells were cultured with (+) or without (−) the Shield-1 ligand for 24 h. In the absence of Shield-1 ligand, only m⁶A-Tracer (green) was expressed and showed predominantly cytoplasmic localization. Following induction, Dam-Lamin B1 (blue) became stabilized and along with m⁶A exhibited ring-like localization patterns at the nuclear lamina. d, HEK293T cells stably co-expressing m⁶A-Tracer–GFP (green, to mark LADs) and Dam-Lamin B1–mAmetrine were cultured with the Shield-1 ligand and immunostained using anti-γH2AX (red) following 100 μg ml⁻¹ zeocin treatment for 4 h. The boxed region is enlarged in the zoom panel. Scale bars, 5 μm, unless specified otherwise in the zoom panel. Source numerical data are provided.