FIGURE 10.

TM accessory subunits of the ND2 and ND4 interface. The structure of mammalian CI (PDB: 6ZKC throughout) in cartoon and the surface of (A) NDUFC2 (green), (B) NDUFC1 (deep orange) and (C) NDUFB1 (red) shown, the core subunits colored as in Figure 1A and the accessory subunits grey. (D) Lipid binding pocket in the mammalian ND2 (thistle purple)/ND4 (pearly purple) interface with the accessory subunits in cartoon and lipids in spheres. (E) Lipid binding in the Y. lipolytica (PDB: 6YJ4) ND2/ND4 interface with the accessory subunits in cartoon and lipids in spheres. (F,G) NDUFC1 alters the structure of ND2 through lipid binding. (F) NDUFC2 and NDUFC1 form a cardiolipin binding pocket with the final TMH^ND2 in O. aries, TMH11^ND2 (PDB: 6ZKC). Positive residues that interact with the cardiolipin, as well as the cardiolipin, are represented as sticks. (G) The cardiolipin pocket is not present in Y. lipolytica which lacks NDUFC1 (PDB: 6YJ4). NDUFC2: green, NDUFC1: deep orange, ND2: thistle purple, ND4: pearly purple, NDUFB11: carrot orange, NDUFB5: cyan azure, NUXM: light cyan.