Biological Assembly 1  

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

Global Symmetry: Dihedral - D2  (3D View)
Global Stoichiometry: Homo 4-mer - A4 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 28.17 kDa 
• Atom Count: 2128 
• Modelled Residue Count: 229 
• Deposited Residue Count: 254 
• Unique protein chains: 1

3TCT

Structure of wild-type TTR in complex with tafamidis

• PDB DOI: 10.2210/pdb3TCT/pdb

• Classification: HORMONE, BINDING PROTEIN
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2011-08-09 Released: 2012-05-30 
• Deposition Author(s): Connelly, S., Kelly, J.W., Wilson, I.A.

---

Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.30 Å
• R-Value Free: 0.192 
• R-Value Work: 0.161 
• R-Value Observed: 0.163 

Literature

Tafamidis, a potent and selective transthyretin kinetic stabilizer that inhibits the amyloid cascade.

Bulawa, C.E., Connelly, S., Devit, M., Wang, L., Weigel, C., Fleming, J.A., Packman, J., Powers, E.T., Wiseman, R.L., Foss, T.R., Wilson, I.A., Kelly, J.W., Labaudiniere, R.

(2012) Proc Natl Acad Sci U S A 109: 9629-9634

• PubMed: 22645360 
• DOI: 10.1073/pnas.1121005109
• Primary Citation of Related Structures:  
  3TCT


• PubMed Abstract: 
  

The transthyretin amyloidoses (ATTR) are invariably fatal diseases characterized by progressive neuropathy and/or cardiomyopathy. ATTR are caused by aggregation of transthyretin (TTR), a natively tetrameric protein involved in the transport of thyroxine and the vitamin A-retinol-binding protein complex. Mutations within TTR that cause autosomal dominant forms of disease facilitate tetramer dissociation, monomer misfolding, and aggregation, although wild-type TTR can also form amyloid fibrils in elderly patients. Because tetramer dissociation is the rate-limiting step in TTR amyloidogenesis, targeted therapies have focused on small molecules that kinetically stabilize the tetramer, inhibiting TTR amyloid fibril formation. One such compound, tafamidis meglumine (Fx-1006A), has recently completed Phase II/III trials for the treatment of Transthyretin Type Familial Amyloid Polyneuropathy (TTR-FAP) and demonstrated a slowing of disease progression in patients heterozygous for the V30M TTR mutation. Herein we describe the molecular and structural basis of TTR tetramer stabilization by tafamidis. Tafamidis binds selectively and with negative cooperativity (K(d)s ~2 nM and ~200 nM) to the two normally unoccupied thyroxine-binding sites of the tetramer, and kinetically stabilizes TTR. Patient-derived amyloidogenic variants of TTR, including kinetically and thermodynamically less stable mutants, are also stabilized by tafamidis binding. The crystal structure of tafamidis-bound TTR suggests that binding stabilizes the weaker dimer-dimer interface against dissociation, the rate-limiting step of amyloidogenesis.

---

Organizational Affiliation: 

Pfizer Orphan and Genetic Diseases Research Unit, Cambridge, MA 02140, USA. [e-mail]

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Transthyretin	A, B	127	Homo sapiens	Mutation(s): 0  Gene Names: PALB, TTR
UniProt & NIH Common Fund Data Resources
Find proteins for P02766 (Homo sapiens) Explore P02766  Go to UniProtKB:  P02766
PHAROS:  P02766 GTEx:  ENSG00000118271

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
3MI	C [auth A], D [auth B]	2-(3,5-dichlorophenyl)-1,3-benzoxazole-6-carboxylic acid C14 H7 Cl2 N O3 TXEIIPDJKFWEEC-UHFFFAOYSA-N

Binding Affinity Annotations
ID	Source	Binding Affinity
3MI	BindingDB:  3TCT	Kd: min: 3, max: 2800 (nM) from 8 assay(s)
		IC50: min: 1550, max: 3100 (nM) from 3 assay(s)
	PDBBind:  3TCT	Kd: 3 (nM) from 1 assay(s)
	Binding MOAD:  3TCT	Kd: 3 (nM) from 1 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.30 Å
• R-Value Free: 0.192 
• R-Value Work: 0.161 
• R-Value Observed: 0.163 
• Space Group: P 2₁ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 42.749	α = 90
b = 84.994	β = 90
c = 64.334	γ = 90

Software Package:

Software Name	Purpose
PHASER	phasing
REFMAC	refinement
HKL-2000	data reduction
HKL-2000	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2011-08-09 
• Released Date: 2012-05-30 
Deposition Author(s): Connelly, S., Kelly, J.W., Wilson, I.A.

Revision History  

• Version 1.0: 2012-05-30
  Type: Initial release
  
• Version 1.1: 2012-08-29
  Changes: Database references