Fig. 6. Relative surface labeling of 1BctA and 1ActB chimeras and related mutants in transfected COS-7 cells, LLC-PK1 cells and hippocampal neurons. Transfection of COS-7 cells (A) and hippocampal neurons (B) with Flag-1BctA (wild type), Flag-I379/380A-1BctA or Flag-C382/385S-1BctA. Surface staining with mouse monoclonal anti-Flag M2 antibody and intracellular labeling with rabbit anti-Flag after plasma membrane permeabilization are shown. Bars, 10 µm. (C) Quantification of the percentage of surface labeling of each construct in transfected COS-7 cells, LLC-PK1 cells and neurons. Data are expressed as mean relative surface labeling ± s.e.m. of 10-15 transfected cells per construct. No significant differences were noted between the two mutants and the wild-type 1BctA chimera. Transfection of COS-7 cells (D) and hippocampal neurons (E) with Flag-1ActB (wild type), Flag-LI414/415A-1ActB or Flag-C419S-1ActB. Bars, 10 µm. (F) Quantification of the percentage of surface labeling of each construct in transfected COS-7 cells, LLC-PK1 cells and neurons. Data are expressed as mean relative surface labeling ± s.e.m. of 10-15 transfected cells per construct. ***P<0.001, when compared with levels in the wild type.