Relative expressions of BRCA2 and ZAR2 mRNAs at different cell cycle stages of human breast cells. (A) RT-PCR analysis showing the expressions of BRCA2 and ZAR2 mRNAs in the unsynchronized (mostly dividing) cells. β-Actin mRNA was used as a loading control. (B) Real-time RT-PCR evaluation of the relative levels of BRCA2 and ZAR2 mRNAs in different human breast cancer cells at G0/G1 and S/G2 phases. The differences between the G0/G1 and S/G2 phase cells were statistically significant (shown by '*'; p < 0.001). (C) Immunofluorescence confocal microscopy showing growth phase-dependent localization of N-terminal FLAG-tagged ZAR2 protein in the synchronized MCF7 cells. Anti-FLAG M2 antibody was used for the detection of FLAG-tagged ZAR2 protein in the cells. The cells were transiently transfected with the expression plasmid constructs and thus not all cells are expressing the recombinant protein.