Suppl. Fig.1

1. No PI Bax Suppl. Fig.1 200 Control 0% Ku80 43.75% Matsuyama b Control c 200 Counts Ku80 8.78% Ku70wt 80 b-Tubulin M1 Counts 0 Control 0.5mg 1.0mg 2.0mg 0 1 2 3 4 10 10 10 10 10 60 FL2-H M1 Ku70 0 0 1 2 3 4 Apoptosis (%) 10 10 10 10 10 40 Ku80 FL2-H Bax+Ku70 Bax+z-VAD b-Tubulin 15.25% 16.49% 20 0 0.5mg 1.0mg 2.0mg Control M1 M1 Bax+Vector Ku80+Vector Bax (1mg)+Ku80 0 1 2 3 4 0 1 2 3 4 10 10 10 10 10 10 10 10 10 10 FL2-H FL2-H a Bax+Ku70 Bax+z-VAD No PI Control 200 Bax 200 200 Counts Counts Counts 0 0 0 M1 0 1 2 3 4 10 10 10 10 10 FL2-H

2. b Suppl. Fig.2 a 1 2 3 4 5 6 7 1 2 3 4 5 8 9 200 200 127 127 85 85 41 Ku70 NS 31 41 Bax 18 31 NS 7 18 7 d c 1 2 3 4 5 8 9 1 2 3 4 5 6 202 7 121 200 79 NS 127 85 NS 41 Ku70 31 NS 41 31 Bax • NRS • Anti-Bax • Mouse IgG • Anti-Ku70 • Molecular Marker • NRS • Anti-Bax • Mouse IgG • Anti-Ku70 17 NS 8 Input 18 7 IP IP Matsuyama

3. a Suppl. Fig.3 Anti-Ku70 Anti-Ku70 1 2 3 4 5 6 7 Anti-Bax Anti-Bax NRS NRS 200 127 85 Ku70 41 31 NS 1 2 3 4 5 8 9 200 Anti-Ku70 18 Anti-Bax d Anti-Ku70 127 Anti-Bax Total NRS NRS b 7 85 1 2 3 4 5 8 9 200 41 127 Ku70 Input Ku70 31 • NRS • Anti-Ku70 • Mouse IgG • Anti-Bax • Molecular Marker • Mouse IgG • Anti-Bax • NRS • Anti-Ku70 85 Bax 18 Bax Input Bax Input 41 NS 7 31 Bax IP NS Ku70 Bax 18 7 IP NS c IP e 2 3 4 5 1 6 7 200 NS 127 85 Cytosol Ku70 41 Ku70 Input Ku70 31 Bax Input Bax 18 NS Bax 7 IP Ku70 Matsuyama

4. a Matsuyama Suppl. Fig.4 d UV treatment time (h) 0 3 6 12 24 200 127 Alkali - + 85 STS - + - + Bax z-VAD - + - + - + - + Ku70 41 b c F1a 31 GFP-Bax P13A GFP-Bax DN GFP-Baxwt 50 GFP 74k 40 18 7 30 Input (GFP-Bax) Apoptosis (%) 32k b-Tubulin 20 STS+z-VAD e 10 Ku70 Input(Ku70) Control STS IP 0 Ku70 200 Bax P13A +Vector Bax P13A +Ku70 Control 127 Bax+Ku70 Bax+Vector 85 f Ku70 No treatment No treatment STS+z-VAD UV+z-VAD 41 STS UV 31 116kDa PARP 85kDa 18 b-Tubulin 7