Membrane targeting and kinase activity of LKB1 are required for haptotaxis. (A) Sequence alignment of vertebrate LKB1 C terminus. Black shade indicates identical amino acids, and gray shade indicates similar amino acids. (B) Western blots of LKB1 reconstitution in LKB498 cells with wild type (WT) or prenylation (C430A), phosphorylation (S428A), and kinase-dead (K78I) mutants. Add, addback. (C) Membrane association and kinase activity are required for haptotaxis. (addback, n = 52; C430A, n = 37; S428A, n = 68; K78I, n = 42.) All data are shown as mean ± 95% confidence intervals. *, P < 0.05 by two-tailed unpaired t test. v, velocity; D/T, displacement (D) over the total path length (T).