Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 10-mer - A10 

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: microscopy

Macromolecule Content

• Total Structure Weight: 172.74 kDa 
• Atom Count: 1800 
• Modelled Residue Count: 240 
• Deposited Residue Count: 1550 
• Unique protein chains: 1

6VW2

Cryo-EM structure of human islet amyloid polypeptide (hIAPP, or amylin) fibrils

• PDB DOI: 10.2210/pdb6VW2/pdb
• EM Map EMD-21410:EMDBEMDataResource

• Classification: PROTEIN FIBRIL
• Organism(s): Saccharomyces cerevisiae S288C, Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2020-02-18 Released: 2020-06-10 
• Deposition Author(s): Cao, Q., Boyer, D.R., Sawaya, M.R., Eisenberg, D.S.
• Funding Organization(s): National Institutes of Health/National Institute on Aging (NIH/NIA)

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 3.40 Å
• Aggregation State: FILAMENT 
• Reconstruction Method: HELICAL 

Literature

Cryo-EM structure and inhibitor design of human IAPP (amylin) fibrils.

Cao, Q., Boyer, D.R., Sawaya, M.R., Ge, P., Eisenberg, D.S.

(2020) Nat Struct Mol Biol 27: 653-659

• PubMed: 32541896 
• DOI: 10.1038/s41594-020-0435-3
• Primary Citation of Related Structures:  
  6VW2


• PubMed Abstract: 
  

Human islet amyloid polypeptide (hIAPP) functions as a glucose-regulating hormone but deposits as amyloid fibrils in more than 90% of patients with type II diabetes (T2D). Here we report the cryo-EM structure of recombinant full-length hIAPP fibrils. The fibril is composed of two symmetrically related protofilaments with ordered residues 14-37. Our hIAPP fibril structure (i) supports the previous hypothesis that residues 20-29 constitute the core of the hIAPP amyloid; (ii) suggests a molecular mechanism for the action of the hIAPP hereditary mutation S20G; (iii) explains why the six residue substitutions in rodent IAPP prevent aggregation; and (iv) suggests regions responsible for the observed hIAPP cross-seeding with β-amyloid. Furthermore, we performed structure-based inhibitor design to generate potential hIAPP aggregation inhibitors. Four of the designed peptides delay hIAPP aggregation in vitro, providing a starting point for the development of T2D therapeutics and proof of concept that the capping strategy can be used on full-length cryo-EM fibril structures.

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Organizational Affiliation: 

Department of Chemistry and Biochemistry and Biological Chemistry, UCLA-DOE Institute, Molecular Biology Institute, and Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, CA, USA. [e-mail].

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Islet amyloid polypeptide (SUMO-tagged)	A, B, C, D, E, F, G, H, I, J	155	Saccharomyces cerevisiae S288C, Homo sapiens This entity is chimeric	Mutation(s): 0  Gene Names: SMT3, YDR510W, D9719.15, IAPP
UniProt & NIH Common Fund Data Resources
Find proteins for P10997 (Homo sapiens) Explore P10997  Go to UniProtKB:  P10997
PHAROS:  P10997 GTEx:  ENSG00000121351
Find proteins for Q12306 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c)) Explore Q12306  Go to UniProtKB:  Q12306
UniProt Groups	Q12306P10997

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 3.40 Å
• Aggregation State: FILAMENT 
• Reconstruction Method: HELICAL 

Structure Validation

Entry History & Funding Information

Deposition Data

• Deposited Date: 2020-02-18 
• Released Date: 2020-06-10 
Deposition Author(s): Cao, Q., Boyer, D.R., Sawaya, M.R., Eisenberg, D.S.

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Funding Organization	Location	Grant Number
National Institutes of Health/National Institute on Aging (NIH/NIA)	United States	AG0543022

Revision History  

• Version 1.0: 2020-06-10
  Type: Initial release
  
• Version 1.1: 2020-07-01
  Changes: Database references
• Version 1.2: 2020-07-22
  Changes: Database references