Fig. 4
Radioresistant cells have global hypo-acetylation and altered HAT and HDAC activities. a Flow cytometry based cell cycle profile of P and RR synchronized in G0/G1 phase and mitosis. b Western blots of site-specific histone PTMs in P and RR synchronized in G0/G1 and mitotic phases of cell cycle. Western blotting was performed using acid-extracted histones from P and RR (c) Densitometry based analysis of western blots. Fold change was calculated after normalizing intensity of RR with P. Fold change of P was taken as 1. d Western blots of MAPK pathway proteins in total cell lysates of P and RR. β-actin serves as loading control. e Graph depicting comparison of HDAC activity between P and RR. Readout of HDAC activity was measured at 405 nm as a colorimetric reaction. TSA depicts negative control consisting of HDAC inhibitor Trichostatin A (f) Graph represents comparison of HAT activity between P and RR. Readout of HAT activity was measured at 440 nm as a colorimetric reaction. Parental MCF7 is denoted as “P” and radioresistant cell line is denoted as “RR”. Statistical analysis is done by Student’s t test. *p < 0.05, **p < 0.01, #—nonspecific band, Abs.—absorbance, TSA—trichostatin A. Error bars represent ± S.D. of 3 experiments