a, CaV1.2(ΔC)/CaVβ3/CaVα2δ-1 side view (left) and extracellular (right) view. Subunits are colored: CaV1.2 (slate) and CaVβ3 (violet). CaVα2δ domains are colored as: dCache1 (aquamarine), dCache2 (orange), VWA:MIDAS (green), and CaVδ (yellow). Grey bars denote the membrane. b-e, CaVα2δ-1 subdomain representative maps for b, VWA:MIDAS domain, c, dCache1, d, dCache2:CaVδ. Part of CaVδ completes the second β-barrel subdomain of dCache2, e, CaVδ. f, GBP-binding site. Maps are rendered at 9–10σ. Domain colors are as in a.