Extended Data Fig. 5: Structural superimposition of Aβ fibril structures and hIAPP fibril structure.

Ten previously reported Aβ fibril structures were superimposed with the hIAPP fibril structure by either directly comparing full-length Aβ fibril structures with the full-length hIAPP structure, or by only comparing residues 24-34 of Aβ fibril structures with residues 19-29 of the hIAPP structure. For the full-length comparison, one Aβ fibril structure (PDB ID 6SHS) shows reasonable alignment with low r.m.s.d., and the structural superimposition is shown on the far left panel, with the Aβ fibril structure shown in grey, the hIAPP structure shown in blue, and the segment that fits best (residues 20-25 of Aβ fibril structure) shown in magenta. For the partial comparison, four Aβ fibril structures show a good fit (middle left), three Aβ fibril structures show a moderate fit (middle right) and four Aβ fibril structures do not fit (far right). In these superimpositions, residues 24-34 of the Aβ fibril structures were colored grey and the highest fitting region (residues 26-31) is colored magenta. Detailed alignment parameters are listed in Supplementary Table 3.