Fig. 8. The dileucine motif is not required for basolateral targeting. (A) Basolateral targeting of EC81LA in MDCK and DLD1 cells. Cells were grown on Transwell filters and either the (a) apical or (b) basolateral membranes were biotinylated. After precipitation of the biotinylated protein using immobilized streptavidin, EC81LA was detected using anti-HA mAbs. (B) Confocal imaging of basolateral targeting of EC81LA. EC81LA and endogenous Na⁺,K⁺-ATPase were detected using anti-HA antibody and antibody against Na⁺,K⁺-ATPase, respectively. (C) EC81LA and ELA do not colocalize with the apical membrane marker gp135. EC81LA and ELA were detected using anti-HA antibody, whereas endogenous gp135 was detected using 3F2 mAb. (D) EC81LA, ELA and EWALA are detected at the basolateral membrane but not the apical membrane. Optical data were obtained as described in Fig. 5D.