N-terminal and C-terminal deletions abrogate increased cell adhesion. Wild-type P210^BCR-ABL or mutants were expressed in 32D cells, and the magnitude of binding between each population and a fibronectin monolayer was determined. Two independently transduced populations of each mutant were tested, and the critical shear stress of individual spins for a single population is shown (•). Rectangles represent 1 SD greater than and less than the mean. Significance values are given at the top of the graph for mutants compared with 2 wild-type P210^BCR-ABL populations (#1 and #2) or at the bottom of the graph when compared with vector control pK1. Wild-type P210^BCR-ABL or functional mutants segregate into 2 groups that have a higher (P210^BCR-ABL, Y177F, and (1-210)) or lower ((1-162), (1-63), Δ(1-63), and ΔActin) ability to bind fibronectin, suggesting that both N-terminal and C-terminal functional domains contribute to increased cell adhesion. Binding of each mutant to BSA-only–coated coverslips was similar for each mutant and was low, comparable to wild-type P210^BCR-ABL or vector control cells (data not shown). (An additional population of pK1 similar to the one shown, as well as wild-type P210^BCR-ABL #2, were previously published.¹³ ). NSD indicates not significantly different.