Figure 6.

Mutations in IR3 increase the activity of Jak2. (A) Schematic presentation of Jak2 constructs. (B) Stat5 expression plasmid was transfected into 293T cells either alone or together with HA-tagged JH1-Jak2, 758-Jak2, LQF-758-Jak2, FYE-758-Jak2, DKH-758-Jak2, QLP-758-Jak2, or APK-758-Jak2, as indicated. Cell lysates were immunoprecipitated using anti-Stat5 antibody, and immunoprecipitates were separated in 7.5% SDS-PAGE followed by immunoblotting with anti-phosphotyrosine (top) and anti-Stat5 antibodies (middle). Cell lysates were separated in 4–15% SDS-PAGE and analyzed by immunoblotting with anti-HA antibody (bottom). The mobilities of the molecular mass markers (in kilodaltons) are shown on the right.