In vitro and in vivo interaction of aa 1 to 63 of BCR (BCC) with p185^(BCR-ABL). (A) Pull down of p185^(BCR-ABL) by GST-BCC. p185^(BCR-ABL)-expressing Ba/F3 cells were incubated with GST and GST-BCC bound to Sepharose beads. The precipitated complexes were resolved on SDS-PAGE and blotted with an α-ABL antibody. (B) Localization of the BCC-GFP fusion peptide in p185^(BCR-ABL)-expressing Ba/F3 cells. Cells were stained with the α-ABL antibody α-ABL; red fluorochrome), or GFP, (BCC-GFP expression; green fluorochrome). Colocalization images were obtained by electronic superimposition of the images (merge). Colocalization of fluorochromes yields a yellow color. The retroviral construct is shown at the top. Original magnification, × 100.