IFNA1 and systemic lupus erythematosus: To investigate the molecular mechanism by which SLE-like B cells undergo direct regulation of ATR by IFN-α, we performed chromatin immunoprecipitation (ChIP) experiments for binding sites of IRF1 on ATR regulatory regions, as predicted by in silico analysis [Eucaryotic Promoter Database (EPD) database] (Fig. 6A).