5IEI

X-ray crystallographic structure of a high affinity IGF2 antagonist (Domain11 AB5 RHH) based on human IGF2R domain 11


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.80 Å
  • R-Value Free: 0.249 
  • R-Value Work: 0.222 
  • R-Value Observed: 0.225 

wwPDB Validation   3D Report Full Report


This is version 1.4 of the entry. See complete history


Literature

Functional evolution of IGF2:IGF2R domain 11 binding generates novel structural interactions and a specific IGF2 antagonist.

Frago, S.Nicholls, R.D.Strickland, M.Hughes, J.Williams, C.Garner, L.Surakhy, M.Maclean, R.Rezgui, D.Prince, S.N.Zaccheo, O.J.Ebner, D.Sanegre, S.Yu, S.Buffa, F.M.Crump, M.P.Hassan, A.B.

(2016) Proc Natl Acad Sci U S A 113: E2766-E2775

  • DOI: 10.1073/pnas.1513023113
  • Primary Citation of Related Structures:  
    2M68, 2M6T, 5IEI

  • PubMed Abstract: 
  • Among the 15 extracellular domains of the mannose 6-phosphate/insulin-like growth factor-2 receptor (M6P/IGF2R), domain 11 has evolved a binding site for IGF2 to negatively regulate ligand bioavailability and mammalian growth. Despite the highly evolved structural loops of the IGF2:domain 11 binding site, affinity-enhancing AB loop mutations suggest that binding is modifiable ...

    Among the 15 extracellular domains of the mannose 6-phosphate/insulin-like growth factor-2 receptor (M6P/IGF2R), domain 11 has evolved a binding site for IGF2 to negatively regulate ligand bioavailability and mammalian growth. Despite the highly evolved structural loops of the IGF2:domain 11 binding site, affinity-enhancing AB loop mutations suggest that binding is modifiable. Here we examine the extent to which IGF2:domain 11 affinity, and its specificity over IGF1, can be enhanced, and we examine the structural basis of the mechanistic and functional consequences. Domain 11 binding loop mutants were selected by yeast surface display combined with high-resolution structure-based predictions, and validated by surface plasmon resonance. We discovered previously unidentified mutations in the ligand-interacting surface binding loops (AB, CD, FG, and HI). Five combined mutations increased rigidity of the AB loop, as confirmed by NMR. When added to three independently identified CD and FG loop mutations that reduced the koff value by twofold, these mutations resulted in an overall selective 100-fold improvement in affinity. The structural basis of the evolved affinity was improved shape complementarity established by interloop (AB-CD) and intraloop (FG-FG) side chain interactions. The high affinity of the combinatorial domain 11 Fc fusion proteins functioned as ligand-soluble antagonists or traps that depleted pathological IGF2 isoforms from serum and abrogated IGF2-dependent signaling in vivo. An evolved and reengineered high-specificity M6P/IGF2R domain 11 binding site for IGF2 may improve therapeutic targeting of the frequent IGF2 gain of function observed in human cancer.


    Organizational Affiliation

    Tumour Growth Control Group, Oxford Molecular Pathology Institute, Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom; matt.crump@bristol.ac.uk bass.hassan@path.ox.ac.uk.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Cation-independent mannose-6-phosphate receptor A142Homo sapiensMutation(s): 10 
Gene Names: IGF2RMPRI
Find proteins for P11717 (Homo sapiens)
Explore P11717 
Go to UniProtKB:  P11717
NIH Common Fund Data Resources
PHAROS:  P11717
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download Ideal Coordinates CCD File 
A
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
GOL
Query on GOL

Download Ideal Coordinates CCD File 
A
GLYCEROL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
EDO
Query on EDO

Download Ideal Coordinates CCD File 
A
1,2-ETHANEDIOL
C2 H6 O2
LYCAIKOWRPUZTN-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.80 Å
  • R-Value Free: 0.249 
  • R-Value Work: 0.222 
  • R-Value Observed: 0.225 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 42.12α = 90
b = 48.56β = 90
c = 62.55γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
xia2data reduction
xia2data scaling
PHASERphasing

Structure Validation

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Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Cancer Research UKUnited KingdomC429/A9891

Revision History  (Full details and data files)

  • Version 1.0: 2016-05-18
    Type: Initial release
  • Version 1.1: 2016-05-25
    Changes: Database references
  • Version 1.2: 2017-08-30
    Changes: Advisory, Author supporting evidence
  • Version 1.3: 2019-02-20
    Changes: Advisory, Data collection, Derived calculations
  • Version 1.4: 2019-07-10
    Changes: Data collection