Figure 4: PAR-dependent accumulation of LCD-containing proteins seeds liquid demixing at sites of DNA damage.

(a) Bright-field images depicting the transient generation of distinct light-diffracting stripes at sites of laser microirradiation under conditions of increased laser energy. White arrows indicate the orientation of the laser line, black arrows point to light-diffracting stripes. Asterisk and dashed lines point to light-diffracting nucleoli. See Supplementary Materials for details. (b) Bright-field images depicting the enhanced and prolonged generation of distinct light-diffracting stripes at sites of laser microirradiation in PARG-depleted cells. See also Supplementary Movie 3. (c) Bright-field images of laser microirradiated PARG-depleted cells in the presence of PARP inhibitor. (d) Bright-field images of laser microirradiated siPARG/FET cells. (e) Transient ectopic expression of GFP–EWS enhances the generation of light-diffracting stripes in otherwise naive U-2-OS cells. Following laser microirradiation, cells were fixed and stained for PAR. White arrows in b–e indicate the orientation of the laser line, black arrows point to light-diffracting stripes. Scale bars, 10 μm.