Crystal structure of insulin receptor kinase domain in complex with an inhibitor Irfin-1

Experimental Data Snapshot

  • Resolution: 1.80 Å
  • R-Value Free: 0.218 
  • R-Value Work: 0.182 
  • R-Value Observed: 0.184 

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This is version 1.3 of the entry. See complete history


A highly selective dual insulin receptor (IR)/insulin-like growth factor 1 receptor (IGF-1R) inhibitor derived from an extracellular signal-regulated kinase (ERK) inhibitor.

Anastassiadis, T.Duong-Ly, K.C.Deacon, S.W.Lafontant, A.Ma, H.Devarajan, K.Dunbrack, R.L.Wu, J.Peterson, J.R.

(2013) J Biol Chem 288: 28068-28077

  • DOI: https://doi.org/10.1074/jbc.M113.505032
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    Dual inhibitors of the closely related receptor tyrosine kinases insulin-like growth factor 1 receptor (IGF-1R) and insulin receptor (IR) are promising therapeutic agents in cancer. Here, we report an unusually selective class of dual inhibitors of IGF-1R and IR identified in a parallel screen of known kinase inhibitors against a panel of 300 human protein kinases. Biochemical and structural studies indicate that this class achieves its high selectivity by binding to the ATP-binding pocket of inactive, unphosphorylated IGF-1R/IR and stabilizing the activation loop in a native-like inactive conformation. One member of this compound family was originally reported as an inhibitor of the serine/threonine kinase ERK, a kinase that is distinct in the structure of its unphosphorylated/inactive form from IR/IGF-1R. Remarkably, this compound binds to the ATP-binding pocket of ERK in an entirely different conformation to that of IGF-1R/IR, explaining the potency against these two structurally distinct kinase families. These findings suggest a novel approach to polypharmacology in which two or more unrelated kinases are inhibited by a single compound that targets different conformations of each target kinase.

  • Organizational Affiliation

    From the Cancer Biology Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Insulin receptor
A, B
306Homo sapiensMutation(s): 1 
Gene Names: INSR
UniProt & NIH Common Fund Data Resources
Find proteins for P06213 (Homo sapiens)
Explore P06213 
Go to UniProtKB:  P06213
PHAROS:  P06213
GTEx:  ENSG00000171105 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP06213
Sequence Annotations
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
Query on IR1

Download Ideal Coordinates CCD File 
C [auth A],
D [auth B]
C18 H10 N6 O
Binding Affinity Annotations 
IDSourceBinding Affinity
IR1 PDBBind:  4IBM IC50: 1800 (nM) from 1 assay(s)
Binding MOAD:  4IBM IC50: 1800 (nM) from 1 assay(s)
Experimental Data & Validation

Experimental Data

  • Resolution: 1.80 Å
  • R-Value Free: 0.218 
  • R-Value Work: 0.182 
  • R-Value Observed: 0.184 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 50.838α = 90
b = 89.21β = 90
c = 142.193γ = 90
Software Package:
Software NamePurpose
MAR345data collection
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

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Ligand Structure Quality Assessment 

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2013-08-21
    Type: Initial release
  • Version 1.1: 2013-08-28
    Changes: Database references
  • Version 1.2: 2013-11-20
    Changes: Database references
  • Version 1.3: 2017-11-15
    Changes: Refinement description