Figure 3. Electron microscopy of UV/cold shock-induced gas formation to cause damage to the nucleus.

COS7 cells were exposed to UV irradiation (480 mJoule/cm²) and then incubated at 4°C for 3 hours. Cells were fixed and prepared for electron microscopy analysis. (A–B) COS7 cells were without treatment. Intact nuclear pores are shown (see arrows). (C–D) A single gas hit to the nuclear wall is shown, which results in burst of the nucleus with a single opening (red arrow).