Micrographs of IAPP (amylin) amyloid fibrils
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ABSTRACT:
SUBMITTER: Gunnar F Schröder
PROVIDER: EMPIAR-11093 | biostudies-other |
REPOSITORIES: biostudies-other
Publications
Cryo-EM structure of islet amyloid polypeptide fibrils reveals similarities with amyloid-β fibrils.
Röder Christine C Kupreichyk Tatsiana T Gremer Lothar L Schäfer Luisa U LU Pothula Karunakar R KR Ravelli Raimond B G RBG Willbold Dieter D Hoyer Wolfgang W Schröder Gunnar F GF
Nature structural & molecular biology 20200615 7
Amyloid deposits consisting of fibrillar islet amyloid polypeptide (IAPP) in pancreatic islets are associated with beta-cell loss and have been implicated in type 2 diabetes (T2D). Here, we applied cryo-EM to reconstruct densities of three dominant IAPP fibril polymorphs, formed in vitro from synthetic human IAPP. An atomic model of the main polymorph, built from a density map of 4.2-Å resolution, reveals two S-shaped, intertwined protofilaments. The segment 21-NNFGAIL-27, essential for IAPP amy ...[more]
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