1R5L

Crystal Structure of Human Alpha-Tocopherol Transfer Protein Bound to its Ligand


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.5 Å
  • R-Value Free: 0.213 
  • R-Value Work: 0.187 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal structure of human alpha-tocopherol transfer protein bound to its ligand: Implications for ataxia with vitamin E deficiency

Min, K.C.Kovall, R.A.Hendrickson, W.A.

(2003) Proc.Natl.Acad.Sci.USA 100: 14713-14718

  • DOI: 10.1073/pnas.2136684100
  • Also Cited By: 1XGG

  • PubMed Abstract: 
  • Human alpha-tocopherol (alpha-T) transfer protein (ATTP) plays a central role in vitamin E homeostasis, preventing degradation of alpha-T by routing this lipophilic molecule for secretion by hepatocytes. Mutations in the gene encoding ATTP have been ...

    Human alpha-tocopherol (alpha-T) transfer protein (ATTP) plays a central role in vitamin E homeostasis, preventing degradation of alpha-T by routing this lipophilic molecule for secretion by hepatocytes. Mutations in the gene encoding ATTP have been shown to cause a severe deficiency in alpha-T, which results in a progressive neurodegenerative spinocerebellar ataxia, known as ataxia with vitamin E deficiency (AVED). We have determined the high-resolution crystal structure of human ATTP with (2R,4'R,8'R)-alpha-T in the binding pocket. Surprisingly, the ligand is sequestered deep in the hydrophobic core of the protein, implicating a large structural rearrangement for the entry and release of alpha-T. A comparison to the structure of a related protein, Sec14p, crystallized without a bona fide ligand, shows a possibly relevant open conformation for this family of proteins. Furthermore, of the known mutations that cause AVED, one mutation, L183P, is located directly in the binding pocket. Finally, three mutations associated with AVED involve arginine residues that are grouped together on the surface of ATTP. We propose that this positively charged surface may serve to orient an interacting protein, which might function to regulate the release of alpha-T through an induced change in conformation of ATTP.


    Organizational Affiliation

    Howard Hughes Medical Institute and Department of Neurology, Columbia University, New York, NY 10032, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
PROTEIN (Alpha-tocopherol transfer protein)
A
262Homo sapiensGene Names: TTPA (TPP1)
Find proteins for P49638 (Homo sapiens)
Go to Gene View: TTPA
Go to UniProtKB:  P49638
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
VIV
Query on VIV

Download SDF File 
Download CCD File 
A
(2R)-2,5,7,8-TETRAMETHYL-2-[(4R,8R)-4,8,12-TRIMETHYLTRIDECYL]CHROMAN-6-OL
C29 H50 O2
GVJHHUAWPYXKBD-IEOSBIPESA-N
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
MSE
Query on MSE
A
L-PEPTIDE LINKINGC5 H11 N O2 SeMET
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.5 Å
  • R-Value Free: 0.213 
  • R-Value Work: 0.187 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 40.096α = 90.00
b = 77.151β = 90.00
c = 85.397γ = 90.00
Software Package:
Software NamePurpose
DENZOdata reduction
CNSrefinement
SOLVEphasing
SCALEPACKdata scaling
ARP/wARPmodel building

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-11-25
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance