All lanes : Anti-DNA PKcs (phospho S2056) antibody - ChIP Grade ( ab18192 ) at 1 µg/ml Lane 1 : HeLa Gamma Irradiated Whole Cell Lysate Pack ( ab13823 ) at 20 µg Lane 2 : 20ug untreated HeLa cell extract Lane 3 : HeLa Gamma Irradiated Whole Cell Lysate Pack ( ab13823 ) at 20 µg with Human DNA PKcs (phospho S2056) peptide (ab20406) at 1 µg/ml Lane 4 : 20ug untreated HeLa cell extract with Human DNA PKcs (phospho S2056) peptide (ab20406) at 1 µg/ml Lane 5 : HeLa Gamma Irradiated Whole Cell Lysate Pack ( ab13823 ) at 20 µg with Human DNA PKcs peptide ( ab20407 ) at 1 µg/ml Lane 6 : 20ug untreated HeLa cell extract with Human DNA PKcs peptide ( ab20407 ) at 1 µg/ml Secondary Alexa Fluor Goat polyclonal to Rabbit IgG (700) at 1/10000 dilution Performed under reducing conditions. Observed band size : 460 kDa ( why is the actual band size different from the predicted? ) Additional bands at : 270 kDa (possible cleavage fragment,cross reactivity).