Fig. 3. The N-terminus regulates the subcellular distribution of p120. (A) Naturally occurring isoforms of p120 that differ only in the length of their N-termini. (B) p120 isoforms 1A, 3A and 4A were retrovirally transduced into E-cadherin-positive (A431) and E-cadherin-negative (A431D) cells. The cells in each figure are representative of the localization seen in the majority of cells. The isoforms show identical distribution in A431 cells (i-iii) but differ in their localization in A431D cells (iv-vi). Incubation with LMB enhanced nuclear levels of p120 1A (vii) and 3A (viii) but had little effect on 4A (ix). (C) The distribution of p120 isoforms in A431D cells before and after LMB treatment was scored by counting random fields of cells (200 cells per slide), and the results are indicated by the bar graphs (n=3). NC, nuclear and cytoplasmic; PC, predominantly cytoplasmic; PN, predominantly nuclear.