Irradiation of cells
Cells were irradiated in the Experimental Irradiation Core of the University of Michigan Comprehensive Cancer Center with 320kV X-rays using an IC-320 cabinet irradiator (Kimtron Medical, Woodbury, CT) with Tungsten anode and a 4 mm Beryllium window with 1.65 mm aluminum filtering.
RT-PCR and qPCR
Amplification primers were: Blimp-1 forward 5′-TGACTTTGTGGACAGAGGCCGAGT-3′ and Blimp-1 reverse 5′-CTGTTGTTGGCAGCATACTTGAAA-3′ (151 bp); BCL-6 forward 5′-CGGGACATCTTGACGGAC-3′ and BCL-6 reverse 5′-CAGGGTGATTTCAGGATATA-3′ TACI forward 5′-CATTCTGCCCCAAAGATCAGT-3′ and TACI reverse 5′-TGGTGCCTTCCTGAGTTGTCT-3′ (316 bp); β-actin forward 5′-TTCTACAATGAGCTGCGTGTG-3′ and β-actin reverse 5′-GCCATCTCCTGCTCGAAGT-3′ (416 bp). The conditions for thermal cycling consisted of denaturation at 94°C for 15 seconds, annealing at 55°C for 15 seconds and extension at 72°C for 30 seconds and a total of 25–35 cycles were performed. The PCR products were run on 1% agarose gels and visualized under ultraviolet light after ethidium bromide staining.