Pathogenic Roles of Glutamic Acid Decarboxylase 65 Autoantibodies in Cerebellar Ataxias

Figure 3

Surface structure of GAD65 showing epitope clusters ctc1 and ctc2. Monomers A and B of the dimeric GAD65 are shown in dark blue and cyan, respectively. Epitope clusters ctc1 and ctc2 on opposing faces of the C-terminal domains are shown. In (b), the molecule is rotated 180° along the vertical axis, and different faces of the C-terminal domain are shown as α, β, γ, and δ faces. Broad epitope locations are shown in yellow and single contact sites for mAb binding in red. The disordered catalytic loop and the COOH-terminal flexible loop are represented by red and red dotted lines, respectively. The epitope bound by GAD65Ab b78 resides primarily on the α and β faces of ctc1, while GAD65Ab b96.11 recognizes an epitope located on the δ and γ faces of ctc2. This figure was adapted from Fenalti et al. (2008) with permission [44].