Fig. 1

Figure 1. Structural features of dr Pcdh19 EC3-6

(A) Ribbon diagram of dr Pcdh19 EC3-6 is shown with a backdrop of the protein’s molecular surface representation.

(B) A topology diagram represents the structural features of dr Pcdh19 EC3-6. β strands are drawn as arrows and labeled A through G. Helices are drawn as rectangles and labeled as α (α helix) or 3₁₀ (3₁₀ helix). Green and yellow circles are Ca²⁺ and Na⁺ ions, respectively.

(C and D) Details of linker regions with canonical (C) and non-canonical Ca²⁺-binding motifs (D) are shown. Residues referred to in the main text have yellow colored carbons.

(E) Na⁺ ion coordination within EC3.

(F) Details of a β bridge located in the β strand A of EC6. β strand A contains three segments labeled A′, A″, and A‴. Select residues have yellow colored carbon atoms to aid in visualization of the β bridge structure.

(G) Molecular surface representation of dr Pcdh19 EC3-6 with residues colored based on chemical properties: hydrophobic (white), polar (green), acidic (red), and basic (blue). Highly hydrophobic regions are highlighted by boxes with dashed outlines. In (A) and (C)–(E), Ca²⁺ (green) and Na⁺ (yellow) ions are shown as spheres, and stick representations are used for ion-coordinating side chains. The subscript “C” indicates only the backbone carbonyl for that residue is shown; the subscript “B” indicates the entire backbone is shown. See also Figures S1–S5.