Fig. 6

3D model of subunit A of human bestrophin-1 (residues 1-366; CPK representation) prepared by homology modelling and relaxed by geometrical optimization in water by molecular mechanics from crystal structure of chicken BEST1 [9, 10]. Ca²⁺ and K⁺ ions of neighbouring subunit B in the chloride channel coordinated by the C-terminal domain residues of subunit A are marked with (B). The locations of individual variant amino acids identified in the probands (Table 1) are shown in purple. a Front view of subunit A with “tail” wrapped around subunit B (channel pore inner side). b Side view (binding site to neighbouring subunit E). c Rear view (membrane side). d Side view (binding site to neighbouring subunit B)