Cells lacking Msl2/hMSL2 have defects in NHEJ repair.

<p>(<b>A</b>) End-joining efficiency in wild-type, <i>Msl2^−/−</i> and <i>Prkdc^−/−</i> DT40 cell lines as determined by GFP expression measured by flow cytometry analysis, following 16 hour transfection of XmnI-digested GFP plasmid. Transfection efficiency was normalized using uncut GFP plasmid. Repair efficiency was compared to wild-type cells. Compared to wild-type (n = 5): <i>p</i> value of <i>Msl2^−/−</i> #1 = 0.0237 (n = 5); <i>p</i> value of <i>Msl2^−/−</i> #2 = 0.0586 (n = 3); and <i>p</i> value of <i>Prkdc^−/− = </i>0.0912 (n = 5). (<b>B</b>) Representative immunoblot showing hMSL2 (upper two panels) and hMOF (lower two panels) depletion achieved using hMSL2 and hMOF siRNA respectively. (<b>C</b>) End-joining repair assay as in (A) in U2OS cells treated with control (cont)- or hMSL2-siRNAs. <i>p</i> value = 0.0014 (n = 4). (<b>D</b>) NHEJ repair efficiency in GC92 cells treated with control-, hMSL2- or hMOF-siRNAs as determined by repair of I-SceI digested intrachromosomal reporter. Quantified as percentage of CD4 positive cells by flow-cytometry analysis. Efficiency is compared to control cells. p value of hMSL2-siRNA treated cells = 0.0318 (n = 4) and p value of hMOF-siRNA treated cells = 0.1947 (n = 2). Error bars represent standard deviation. Two-tailed Student’s <i>t</i>-test was used to generate <i>p</i> values.