Journal: Nucleic Acids Research
Article Title: RNF8 mediates NONO degradation following UV-induced DNA damage to properly terminate ATR-CHK1 checkpoint signaling
doi: 10.1093/nar/gky1166
Figure Lengend Snippet: RNF8-mediated degradation of NONO is required for S phase progression by terminating ATR-CHK1 checkpoint signaling in UV-DDR. ( A ) RNF8 depletion causes sustained ATR-CHK1 checkpoint signaling during UV DNA damage. HeLa cells transfected with control siRNA or RNF8 siRNA were exposed to UV (30 J/m 2 ) radiation for the designated time points. Cells were lysed and processed for Western blotting analysis. ( B ) Ectopic expression of stable triple lysine mutant NONO leads to prolonged activation of ATR-CHK1 checkpoint signaling. HeLa cells were transfected with FLAG-NONO and FLAG-NONO K279/290/295R and then treated with UV (30 J/m 2 ) for the indicated time points. Cell lysates were probed with the indicated antibodies for Western blotting analysis. ( C ) Stabilization of NONO delays S-phase progression after UV DNA damage. HeLa cells transfected with FLAG-NONO and FLAG-NONO K279/290/295R were irradiated with UV (10 J/m 2 ) for the indicated time intervals, and DNA content was analyzed by FACS analysis using propidium iodide staining. The cell cycle profiles were quantified and depicted in the top right corner of the figures. ( D ) Clonogenic survival of U2OS-derived stable cell lines expressing the GFP-tagged NONO wild type or the triple lysine (3KR) NONO mutant after UV radiation. Curves show mean ± s.d. of three independent experiments. **** P < 0.0001; P -values represent two-way ANOVA results.
Article Snippet: NONO siRNA duplexes (5′-CAGGCGAAGUCUUCAUUCA-3′) , RNF8 siRNA duplexes (5′-UGCGGAGUAUGAAUAUGAA-3′) ( , ), XPC siRNA duplexes (5′-GGA GGGCGAUGAAACGUUU-3′) ( ) and control siRNA duplexes (5′-CCUACGCCACCAAUUUGGU-3′) were synthesized at Bioneer. siRNA transfection was performed using Lipofectamine RNAimax reagent (Invitrogen) according to the manufacturer's instructions.
Techniques: Transfection, Control, Western Blot, Expressing, Mutagenesis, Activation Assay, Irradiation, Staining, Derivative Assay, Stable Transfection