5IHH

Crystal structure of human transthyretin in complex with luteolin-MeO at 1.35 A resolution


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.35 Å
  • R-Value Free: 0.166 
  • R-Value Work: 0.139 

wwPDB Validation 3D Report Full Report


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Literature

Modifications of the 7-Hydroxyl Group of the Transthyretin Ligand Luteolin Provide Mechanistic Insights into Its Binding Properties and High Plasma Specificity.

Nilsson, L.Larsson, A.Begum, A.Iakovleva, I.Carlsson, M.Brannstrom, K.Sauer-Eriksson, A.E.Olofsson, A.

(2016) Plos One 11: e0153112-e0153112

  • DOI: 10.1371/journal.pone.0153112
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Amyloid formation of the plasma protein transthyretin (TTR) has been linked to familial amyloid polyneuropathy and senile systemic amyloidosis. Binding of ligands within its natural hormone binding site can stabilize the tetrameric structure and impa ...

    Amyloid formation of the plasma protein transthyretin (TTR) has been linked to familial amyloid polyneuropathy and senile systemic amyloidosis. Binding of ligands within its natural hormone binding site can stabilize the tetrameric structure and impair amyloid formation. We have recently shown that the flavonoid luteolin stabilizes TTR in human plasma with a very high selectivity. Luteolin, however, is inactivated in vivo via glucuronidation for which the preferred site is the hydroxy group at position 7 on its aromatic A-ring. We have evaluated the properties of two luteolin variants in which the 7-hydroxy group has been exchanged for a chlorine (7-Cl-Lut) or a methoxy group (7-MeO-Lut). Using an in vitro model, based on human liver microsomes, we verified that these modifications increase the persistence of the drug. Crystal structure determinations show that 7-Cl-Lut binds similarly to luteolin. The larger MeO substituent cannot be accommodated within the same space as the chlorine or hydroxy group and as a result 7-MeO-Lut binds in the opposite direction with the methoxy group in position 7 facing the solvent. Both 7-Cl-Lut and 7-MeO-Lut qualify as high-affinity binders, but in contrast to luteolin, they display a highly non-specific binding to other plasma components. The binding of the two conformations and the key-interactions to TTR are discussed in detail. Taken together, these results show a proof-of-concept that the persistence of luteolin towards enzymatic modification can be increased. We reveal two alternative high-affinity binding modes of luteolin to TTR and that modification in position 7 is restricted only to small substituents if the original orientation of luteolin should be preserved. In addition, the present work provides a general and convenient method to evaluate the efficacy of TTR-stabilizing drugs under conditions similar to an in vivo environment.


    Organizational Affiliation

    Department of Medical Biochemistry and Biophysics, Umeå University, SE-901 87, Umeå, Sweden.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Transthyretin
A, B
127Homo sapiensMutation(s): 0 
Gene Names: TTR (PALB)
Find proteins for P02766 (Homo sapiens)
Go to Gene View: TTR
Go to UniProtKB:  P02766
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
NA
Query on NA

Download SDF File 
Download CCD File 
A
SODIUM ION
Na
FKNQFGJONOIPTF-UHFFFAOYSA-N
 Ligand Interaction
6B5
Query on 6B5

Download SDF File 
Download CCD File 
A, B
2-(3,4-dihydroxyphenyl)-5-hydroxy-7-methoxy-4H-1-chromen-4-one
7,8-DIMETHYLALLOXAZINE; 6,7-DIMETHYLALLOXAZINE
C16 H12 O6
RRRSSAVLTCVNIQ-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.35 Å
  • R-Value Free: 0.166 
  • R-Value Work: 0.139 
  • Space Group: P 21 2 21
Unit Cell:
Length (Å)Angle (°)
a = 42.886α = 90.00
b = 63.834β = 90.00
c = 85.950γ = 90.00
Software Package:
Software NamePurpose
Aimlessdata scaling
PHENIXrefinement
XDSdata reduction
PHASERphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Swedish Research CouncilSweden--

Revision History 

  • Version 1.0: 2016-04-20
    Type: Initial release