(a, b) Representative immunoblots of transiently transfected HEK293 cells comparing trafficking under control conditions at 37°C, at reduced temperature (27°C, 24hrs) or in E4031 (E4, 24 hrs). Dashes (-) indicate the 140kD molecular weight marker. Mutations are color-coded as follows: trafficking deficient and uncorrectable in red, trafficking deficient but correctable at 27°C in yellow, trafficking deficient but correctable at 27°C or with E4031 in light blue and those that traffic similar to WT in blue. (c) Model of the C-linker/CNBHD with C-linker region in green, CNBHD in blue, and intrinsic ligand in magenta. Mapped LQT2 residues correspond to panel A and uncharacterized mutations (L678P, L693P, I728F) are black. (d) Representation of the EAGD (colored wheat) (PDB: 4HP9) complexed with the C-linker/CNBHD model from alignments to the structure of the EAGD-CNBHD complex from mouse (PDB: 4LLO).