Quantification of total and surface-associated hERG protein in cells maintained at lower temperatures. Cells were cultured for 3 d and analyzed by flow cytometry. Data were averaged from 6 samples, each of 5000 cells (un-gated), and normalized against CHO hERG at 37°C. Normalized fluorescence intensity of fixed and permeablized CHO hERG (open bars) and untransfected control CHO cells (filled bars) at the respective temperatures stained with antibody C20 (which is raised against a C-terminal peptide sequence; A). Representative population fluorescence plots for CHO hERG cells from 37, 30 and 27°C in the same experiment as A (B). Normalized surface fluorescence intensity of non-fixed and non-permeablised CHO hERG (open bars) and control cells (filled bars) maintained at the respective temperatures stained with antibody 2110 (which is raised against a peptide between TM1 and TM2 which is predicted to be located on the surface of the plasma membrane; C).