Figure S7 Noxa-initiated death via Bak/BaxCS is inhib- ited by Bcl-xL. (A) FLAG-Bcl-xL was stably expressed in bak2/ 2bax2/2 MEFs expressing Bak/BaxCS. Cell lysates were immunblotted for FLAG or Bak. (B) Bcl-xL is particularly efficient at blocking Noxa-induced death. bak2/2bax2/2 MEFs expressing Bak/BaxCS with or without FLAG-Bcl-xL were retrovirally infected with BimS, or with BimS containing the Noxa or Bad BH3 domains. Percentage cell death was assessed after 36 h by propidium iodide uptake. Data is mean +/2 SEM of two experiments. Statistical significance for the effect of Bcl-xL is shown; *p,0.05. (TIF) Figure S8 Bak/BaxCS is regulated like Bak rather than like Bax. bak2/2bax2/2 MEFs stably expressing Bak, Bak/ BaxCS or Bax (as in Figure 6) were treated with etoposide 2 (10 mM), UV (100 J/m ), cycloheximide (CHX, 50 mg/ml) or actinomycin D (ActD, 1 mM) for 24 h. Percentage cell death is expressed as the mean 6 SEM from two independent experi- ments. 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Ausili A, Torrecillas A, Martinez-Senac MM, Corbalan-Garcia S, Gomez- Fernandez JC (2008) The interaction of the Bax C-terminal domain with PLoS ONE | www.plosone.org 12 March 2012 | Volume 7 | Issue 3 | e31510