Effect of ectopic Myc-MAL2 expression on MCF-10A cell morphology and intracellular localisation of MUC1. (a) MCF-10A and MCF-10A/Myc-MAL2 cells were grown in culture and their morphologies compared by light microscopy (X100 magnification). (b) MCF-10A and MCF-10A/Myc-MAL2 cells were co-stained for MUC1 (left panel) and MAL2 (middle panel). Overlap between the MUC1 and MAL2 proteins are shown in merged images (right panel). Images shown are single horizontal x-y sections. (c) MCF-10A and MCF-10A/Myc-MAL2 cells were extracted with 1% Triton X-100 at 4°C, and centrifuged to equilibrium in sucrose density gradients. Twelve fractions of 1 ml were collected (Fr, as shown above each top panel), and aliquots were subjected to SDS-PAGE and Western blot analysis with MUC1, MAL2 or CAV1 antisera, as indicated at the left, with sizes of detected proteins indicated at the right. Vertical lines between fractions 8 and 9 distinguish samples loaded on different gels. Results shown represent those obtained from 3 independent experiments.