Fig. 2: Positive charged S6Cyto region is critical for the channel gating.
From: Structure, gating, and pharmacology of human CaV3.3 channel
a The pore domain segments in the DI/DIII (left panel) and DII/DIV (right panel) of the CaV3.3 (colored), superimposed with the corresponding region of CaV3.1 structure (gray). b Zoom-in view highlights the structural comparison S6II helix between CaV3.3apo and CaV3.1 (PDB ID: 6KZO) (gray). The shifts of the side chain of residue on S6II helix between CaV3.3apo and CaV3.1 undergoing axial rotation are indicated by red arrows. c Sequence alignment of S6III helix of all human CaV members, numbered according to full-length subunits. The secondary structure of CaV2.2 and CaV3.3 marked above and below the sequence alignment, respectively. The dashes represent gaps. The positively charged residues on S6III are shaded in blue. Residues involved in CaV3.33G are marked by red triangle. d The pore domain segments in the DI/DIII of the CaV3.3apo (colorful) and CaV2.2 (PDB ID: 7VFS) (yellow) are superimposed. The S6Cyto and S6TM regions are indicated. The positively charged residues on the S6Cyto region are shown as blue spheres. e. Normalized conductance-voltage (G/V) and current-voltage(I/V) relationship for the CaV3.3WT construct (black) and mutant CaV3.312Q (blue), triple-mutant CaV3.33G (red). n represents the number of repeated measurements. N cells were analyzed (WT, n = 24; CaV3.312Q, n = 8; CaV3.33G, n = 7). Data are presented as mean values ± SEM. Source data are provided as a Source Data file.
