JAK2 promotes RAD51 focus formation in Ba/F3 cell lines. (A) Ba/F3-EPOR cells were infected with the empty retroviral vector or viruses encoding JAK2wt or JAK2V617F, and RAD51 protein levels were analyzed by Western blotting using an anti-RAD51 antibody. (B) Cells with RAD51 foci (green) after immunostaining in spontaneous condition. Alternatively, Ba/F3-EPOR cells were treated for 3 hours with MMC as a positive control. (C,D) The percentages of cells with RAD51 foci (C) or the number of RAD51 foci per cell (D) were calculated after immunostaining with RAD51 antibody. A total of 200 cells were counted in 3 independent experiments; the percentages are the means plus or minus SD (n = 3). *Statistical significance (P < .05) using Student t test. (E) Cell-cycle distributions of Ba/F3-EPOR, Ba/F3-JAK2wt, and Ba/F3-JAK2V617F cells in culture conditions containing EPO were analyzed by cytometry analysis after propidium iodide staining. Percentages of cells in each phase are indicated.
