Figure 3
From: Apoptosome: a platform for the activation of initiator caspases
Domain organization of Apaf-1 and Dark apoptosomes. (a) Overall structure of the WD40-deleted Apaf-1.53 The left and middle panels display two perpendicular views of the ribbon diagram of the structure of Apaf-1 (residues 1–591, bound to ADP). The WD40-deleted Apaf-1 sequentially comprises five distinct domains, CARD (colored green), an α/β domain (blue), helical domain I (HD1, cyan), a winged-helix domain (WHD, magenta), and helical domain II (HD2, red). These five domains pack against one another to generate a relatively compact structure. ADP binds to the hinge region between the α/β-fold and HD1 but is also coordinated by two critical residues from the WHD. The right panel shows the structure in surface representation except the CARD domain. (b) Domain organization in Apaf-1 apoptosome.55 Left panel shows a top view of the apoptosome.55 Middle panel shows the proposed domain organization in the apoptosome within semitransparent surfaces.55 Right panel shows a cartoon model of the apoptosome.55 Color-coding scheme for the middle and right panels is the same as in (a). (c) Domain organization in the Dark-apoptosome.59 Left panel shows a top view of the Dark-apoptosome.59 Middle panel shows the proposed domain organization in the Dark-apoptosome within semitransparent surfaces.59 Right panel shows a cartoon model of the Dark-apoptosome.59 Color-coding scheme for the middle and right panels is the same as in (a). Compared to Apaf-1-apoptosome, the α/β domain of Dark shifts outwards within the central hub to contact the β6-propeller. Panels b and c were reproduced from the original publication with permission59
