1SN5

Crystal Structure of Sea Bream Transthyretin in complex with Triiodothyronine at 1.90A Resolution


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.211 
  • R-Value Work: 0.173 
  • R-Value Observed: 0.177 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

High resolution crystal structures of piscine transthyretin reveal different binding modes for triiodothyronine and thyroxine.

Eneqvist, T.Lundberg, E.Karlsson, A.Huang, S.Santos, C.R.Power, D.M.Sauer-Eriksson, A.E.

(2004) J Biol Chem 279: 26411-26416

  • DOI: 10.1074/jbc.M313553200
  • Primary Citation of Related Structures:  
    1SN2, 1SN0, 1SN5

  • PubMed Abstract: 
  • Transthyretin (TTR) is an extracellular transport protein involved in the distribution of thyroid hormones and vitamin A. So far, TTR has only been found in vertebrates, of which piscine TTR displays the lowest sequence identity with human TTR (47%). ...

    Transthyretin (TTR) is an extracellular transport protein involved in the distribution of thyroid hormones and vitamin A. So far, TTR has only been found in vertebrates, of which piscine TTR displays the lowest sequence identity with human TTR (47%). Human and piscine TTR bind both thyroid hormones 3,5,3'-triiodo-l-thyronine (T(3)) and 3,5,3',5'-tetraiodo-l-thyronine (thyroxine, T(4)). Human TTR has higher affinity for T(4) than T(3), whereas the reverse holds for piscine TTR. X-ray structures of Sparus aurata (sea bream) TTR have been determined as the apo-protein at 1.75 A resolution and bound to ligands T(3) and T(4), both at 1.9 A resolution. The apo structure is similar to human TTR with structural changes only at beta-strand D. This strand forms an extended loop conformation similar to the one in chicken TTR. The piscine TTR.T(4) complex shows the T(4)-binding site to be similar but not identical to human TTR, whereas the TTR.T(3) complex shows the I3' halogen situated at the site normally occupied by the hydroxyl group of T(4). The significantly wider entrance of the hormone-binding channel in sea bream TTR, in combination with its narrower cavity, provides a structural explanation for the different binding affinities of human and piscine TTR to T(3) and T(4).


    Organizational Affiliation

    Umea Centre for Molecular Pathogenesis, Umea University, SE-901 87 Umea, Sweden.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
transthyretinABCD130Sparus aurataMutation(s): 0 
Find proteins for Q9PTT3 (Sparus aurata)
Explore Q9PTT3 
Go to UniProtKB:  Q9PTT3
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
T3
Query on T3

Download CCD File 
C, D
3,5,3'TRIIODOTHYRONINE
C15 H12 I3 N O4
AUYYCJSJGJYCDS-LBPRGKRZSA-N
 Ligand Interaction
SO4
Query on SO4

Download CCD File 
A
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.211 
  • R-Value Work: 0.173 
  • R-Value Observed: 0.177 
  • Space Group: P 41
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 58.284α = 90
b = 58.284β = 90
c = 138.904γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
DENZOdata reduction
SCALEPACKdata scaling
CNSphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2004-08-03
    Type: Initial release
  • Version 1.1: 2008-04-29
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Advisory, Refinement description, Version format compliance
  • Version 1.3: 2014-04-30
    Changes: Data collection