Untreated (–) and treated (+) 293T whole cell extracts (30 μg) were separated by 7.5% SDS-PAGE, and the membrane was blotted with Chk2 (phospho Ser19) antibody (GTX133989) diluted at 1:500. The HRP-conjugated anti-rabbit IgG antibody (GTX213110-01) was used to detect the primary antibody.