FIG. 5.

Expression and localization of Rab3A in normal mammary epithelial cells. (A) Serum-starved HC11 cells were treated with HRG for 6 h, and the expression of Rab3A was examined by Northern blot analysis. Con, control. CHX, cycloheximide. (B) Expression of Rab3A protein in HC11 cells. −, untreated; +, HRG treated. (C) (Upper panels) HC11 cells were transiently transfected with T7-Rab3A treated with HRG for 6 h, and localization of T7-Rab3A was visualized by immunostaining and confocal microscopy. (Lower panels) HC11 cells were treated with or without HRG for 6 h, and localization of endogenous Rab3A was visualized by immunostaining with a monoclonal antibody and by confocal microscopy. CON, control. (D) HC11 cells were allowed to become competent for differentiation, as described in Materials and Methods, and were treated with DIP components separately or together. Rab3A expression was analyzed by immunoblotting (IB). Con, control.