3QS7

Crystal structure of a human Flt3 ligand-receptor ternary complex


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 4.30 Å
  • R-Value Free: 0.281 
  • R-Value Work: 0.260 
  • R-Value Observed: 0.261 

wwPDB Validation   3D Report Full Report


Ligand Structure Quality Assessment 


This is version 1.5 of the entry. See complete history


Literature

Structural insights into the extracellular assembly of the hematopoietic Flt3 signaling complex.

Verstraete, K.Vandriessche, G.Januar, M.Elegheert, J.Shkumatov, A.V.Desfosses, A.Van Craenenbroeck, K.Svergun, D.I.Gutsche, I.Vergauwen, B.Savvides, S.N.

(2011) Blood 118: 60-68

  • DOI: https://doi.org/10.1182/blood-2011-01-329532
  • Primary Citation of Related Structures:  
    3QS7, 3QS9

  • PubMed Abstract: 

    The class III receptor tyrosine kinase (RTKIII) Fms-like tyrosine kinase receptor 3 (Flt3) and its cytokine ligand (FL) play central roles in hematopoiesis and the immune system, by establishing signaling cascades crucial for the development and homeostasis of hematopoietic progenitors and antigen-presenting dendritic cells. However, Flt3 is also one of the most frequently mutated receptors in hematologic malignancies and is currently a major prognostic factor and clinical target for acute myeloid leukemia. Here, we report the structural basis for the Flt3 ligand-receptor complex and unveil an unanticipated extracellular assembly unlike any other RTKIII/V complex characterized to date. FL induces dimerization of Flt3 via a remarkably compact binding epitope localized at the tip of extracellular domain 3 of Flt3, and it invokes a ternary complex devoid of homotypic receptor interactions. Comparisons of Flt3 with homologous receptors and available mutagenesis data for FL have allowed us to rationalize the unique features of the Flt3 extracellular assembly. Furthermore, thermodynamic dissection of complex formation points to a pronounced enthalpically driven binding event coupled to an entropic penalty. Together, our data suggest that the high-affinity Flt3:FL complex is driven in part by a single preformed binding epitope on FL reminiscent of a "lock-and-key" binding mode, thereby setting the stage for antagonist design.


  • Organizational Affiliation

    Unit for Structural Biology, Laboratory for Protein Biochemistry and Biomolecular Engineering (L-ProBE), Ghent University, Ghent, Belgium.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
SL cytokine
A, B, C, D
138Homo sapiensMutation(s): 0 
Gene Names: FLT3LG
UniProt & NIH Common Fund Data Resources
Find proteins for P49771 (Homo sapiens)
Explore P49771 
Go to UniProtKB:  P49771
GTEx:  ENSG00000090554 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP49771
Sequence Annotations
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
FL cytokine receptor
E, F, G, H
423Homo sapiensMutation(s): 0 
Gene Names: FLT3STK1
EC: 2.7.10.1
UniProt & NIH Common Fund Data Resources
Find proteins for P36888 (Homo sapiens)
Explore P36888 
Go to UniProtKB:  P36888
PHAROS:  P36888
GTEx:  ENSG00000122025 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP36888
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 4.30 Å
  • R-Value Free: 0.281 
  • R-Value Work: 0.260 
  • R-Value Observed: 0.261 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 103.89α = 90
b = 146.26β = 109.66
c = 105.95γ = 90
Software Package:
Software NamePurpose
XSCALEdata scaling
PHASERphasing
BUSTER-TNTrefinement
PDB_EXTRACTdata extraction
BUSTERrefinement

Structure Validation

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Ligand Structure Quality Assessment 


Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2011-03-16
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 1.2: 2011-07-20
    Changes: Database references
  • Version 1.3: 2020-07-29
    Type: Remediation
    Reason: Carbohydrate remediation
    Changes: Data collection, Database references, Derived calculations, Structure summary
  • Version 1.4: 2021-03-31
    Changes: Source and taxonomy, Structure summary
  • Version 1.5: 2023-09-13
    Changes: Data collection, Database references, Refinement description