Extended Data Fig. 7: A potential lumenal half-channel at core subunit ND2.

View along the membrane arm. In the Arabidopsis I + III2 supercomplex, a water-filled part of the central aqueous passage around the ND2 π-bulge (transparent red, white dotted ellipse) is blocked on the lumenal side (horizontal black line) by the sidechain of ND2 Y412 and an adjacent detergent molecule (GDN, green). Waters in red; GDN, glyco-diosgenin.