A greater propensity for STAT6 mutant proteins vs STAT6 wt proteins to reside in the nucleus before and after IL-4 stimulation. (A-C) Subcellular fractionation. Stably transfected lymphoma cell lines OCI-LY7 and OCI-LY8 and transiently transfected HEK293T cells were fractionated by using hypotonic cell lysis (cytoplasmic fraction) followed by high salt extractions (nuclear fraction), and protein was prepared for immunoblotting with antibodies to HA, p-STAT6-Y641, laminB1, and tubulin. IL-4 stimulation and STAT6 mutant and double mutant status is indicated at the top. (D) Immunofluorescence. Results of confocal immunofluorescence detection of HA-tagged STAT6 wt and STAT6 419G in stably transfected lymphoma cells and transiently transfected HEK293T cells. Red, anti-HA; blue, 4,6 diamidino-2-phenylindole staining. IL-4 stimulation is indicated.