Figure 5.

 Knockdown of DNA‐PKcs or mTOR reduces the ATM abundance. HeLa TetOff cells were transfected with two independent siRNA targeted to each phosphatidylinositol 3‐kinase‐related protein kinase (PIKK). Sixty hours after the transfections, total cell lysates were analyzed by western blotting with the indicated antibodies. To estimate the PIKK abundance, 33 and 11% of the nonsilencing (NS) control sample were loaded. The relative protein levels of each PIKK compared with the NS control levels were graphed. The values are an average of the data from two siRNA from two independent experiments. ATM, ataxia telangiectasia mutated; ATR, ATM‐and Rad3‐related; DNA‐PKcs, DNA‐dependent protein kinase catalytic subunit; mTOR, mammalian target of rapamycin; SMG‐1, suppressor with morphological effect on genitalia 1; TRRAP, transformation/transcription domain‐associated protein.