A homology model of Nav1.5 suggests that E1784E associates with K1493 in the DIII–DIV linker. (A) Homology model of the Nav1.5 sequence on the NavPaS structure. The C terminus, DIII–DIV linker, and DIVS4–S5 linker are colored pink, blue, and green, respectively. Black and red boxes show the channel region shown in B and C, respectively. (B) In the homology model, the C terminus of the channel (in pink) is folded back toward the underside of the DIV voltage sensor (in green). (C) In the homology model of Nav1.5, residue E1784E comes within 5 Å of residue K1493 in the DIII–DIV linker. All residues with atoms with 5 Å of E1784E are shown as sticks (PDB accession no. 5X0M; Shen et al., 2017).