Figure 8.

Enhanced activation of JAK2 and STAT5 in BCR-ABL inducible BaF3 cells cotransduced with Ahi-1 and detection of a AHI-1–BCR-ABL–JAK2 interaction complex in human K562 cells. (A and B) Western blot analyses of cell lysates from control BaF3, BCR-ABL–inducible cells, and two Ahi-1–transduced BCR-ABL–inducible clonal lines cultured in the presence (A) and absence (B) of IL-3 ± Dox for 24 h. Antibodies used are indicated. (C–H) Protein lysates of K562 cells (BCR-ABL⁺) and Hut 78 cells (BCR-ABL⁻) were used to immunoprecipitate AHI-1 (C, E-F, and H), ABL (D), and JAK2 (G), and proteins were detected by Western blotting with antibodies to ABL (C), AHI-1 (D, F, and G), JAK-2 (G), and phosphotyrosine (E and H) as indicated. In H, before immunoprecipitation, lysates were incubated for 1 h with the indicated AHI-1 peptide; unrelated peptide (unr.), no peptide (-), and antigenic peptide (+) or cells were incubated ± IM (5 μM) for 6 h before preparation of protein lysates.