Structure of human β-spectrin repeats 14 and 15, the ankyrin binding domain. Stereo diagram of β-spectrin repeats 14 and 15 corresponding to the ankyrin binding domain. The structure displays a canonical spectrin fold consisting of 3-helix bundles connected by a helical linker. Repeat 14 is shown in blue and repeat 15, which contains some disordered regions distal to repeat 14, is in red. Helices are marked as A, B, or C, corresponding to the first, second, or third helix of each bundle, respectively. Rotating views of several representations of the molecule are shown in Video S1.