Fig 2: Interaction of INPP4B with Rad50 and destabilization of Rad50 upon loss of INPP4B.a Rad50 was identified from immuno-precipitated INPP4B complexes by mass spectrometry. b Reciprocal verification of the interaction between INPP4B and Rad50 in A549 cells. Two micrograms of antibodies against INPP4B or Rad50 were used for each reciprocal immunoprecipitation in a total of 2 mg of A549 cell lysates, and the precipitated proteins were resolved on 6% SDS–PAGE gel and detected with the indicated antibodies. In IR treatments, cells were harvested at 2 h post IR. c Representative Western blot images for measuring the stability of Rad50 in CTL and Crispr-INPP4B A549 cells. The half-life of Rad50 in each cell line was determined by densitometry scanning compared to the signal intensity at time zero with CHX treatment, and normalized to GAPDH signal. The average half-life of Rad50 was based on three independent CHX treatments and plotted in d, and data are presented as means ± SD (min). An error bar represents SD. Asterisk (*) indicates p < 0.05 by Student’s t-test.