1. a-FEN1 a-C23 DAPI merge 0h 2h 4h 8h
FIG. S1. UV treatment drives FEN1 out of nucleoli in HMCB cells. The cells were washed twice in warm PBS (pH 7.4) and treated with UV-C (120 J/m2) using a UV Stratalinker 1800 (Stratagene, La Jolla, CA) with the lids removed. After irradiation the cells were supplied with complete medium and harvested at the indicated times. Cell immunofluorescence staining was performed as described in Materials and methods.
FEN1 positive nucleoli at 0h: 98%; 2h: 11%; 4h: 3%; 8h: 99%, while more than 1,000 cells were counted in each case.