Subcellular distribution of Jak1 and Jak2. (A) Jak2^−/− MEFs were transiently transfected with plasmid constructs that encode for HA-tagged Jak1-Wt and V5-tagged Jak2-Wt, Jak2-FF, Jak2-ΔJH1, or Jak2-ΔJH1+2. Then 24 hours posttransfection, the cells were fixed and stained with anti-HA (blue), and anti-V5 (green) antibodies. Subsequently, samples were analyzed by confocal microscopy. Bars, 10 µm. (B) Jak2^−/− MEFs were transiently transfected with HA-tagged Jak2-Wt and V5-tagged Jak2-FF expression plasmid constructs. Then 24 hours posttransfection, the cells were fixed and stained with anti-HA (red), anti-V5 antibodies (green), and DAPI (blue). Subsequently, samples were analyzed by confocal microscopy. Bars, 10 µm. The histogram depicts fluorescence values the cross selection through the cell as indicated.