3FQ9

Design of an insulin analog with enhanced receptor-binding selectivity. Rationale, structure, and therapeutic implications


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.35 Å
  • R-Value Free: 0.228 
  • R-Value Work: 0.198 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Design of an insulin analog with enhanced receptor binding selectivity: rationale, structure, and therapeutic implications.

Zhao, M.Wan, Z.L.Whittaker, L.Xu, B.Phillips, N.B.Katsoyannis, P.G.Ismail-Beigi, F.Whittaker, J.Weiss, M.A.

(2009) J Biol Chem 284: 32178-32187

  • DOI: 10.1074/jbc.M109.028399
  • Primary Citation of Related Structures:  
    3FQ9

  • PubMed Abstract: 
  • Insulin binds with high affinity to the insulin receptor (IR) and with low affinity to the type 1 insulin-like growth factor (IGF) receptor (IGFR). Such cross-binding, which reflects homologies within the insulin-IGF signaling system, is of clinical ...

    Insulin binds with high affinity to the insulin receptor (IR) and with low affinity to the type 1 insulin-like growth factor (IGF) receptor (IGFR). Such cross-binding, which reflects homologies within the insulin-IGF signaling system, is of clinical interest in relation to the association between hyperinsulinemia and colorectal cancer. Here, we employ nonstandard mutagenesis to design an insulin analog with enhanced affinity for the IR but reduced affinity for the IGFR. Unnatural amino acids were introduced by chemical synthesis at the N- and C-capping positions of a recognition alpha-helix (residues A1 and A8). These sites adjoin the hormone-receptor interface as indicated by photocross-linking studies. Specificity is enhanced more than 3-fold on the following: (i) substitution of Gly(A1) by D-Ala or D-Leu, and (ii) substitution of Thr(A8) by diaminobutyric acid (Dab). The crystal structure of [D-Ala(A1),Dab(A8)]insulin, as determined within a T(6) zinc hexamer to a resolution of 1.35 A, is essentially identical to that of human insulin. The nonstandard side chains project into solvent at the edge of a conserved receptor-binding surface shared by insulin and IGF-I. Our results demonstrate that modifications at this edge discriminate between IR and IGFR. Because hyperinsulinemia is typically characterized by a 3-fold increase in integrated postprandial insulin concentrations, we envisage that such insulin analogs may facilitate studies of the initiation and progression of cancer in animal models. Future development of clinical analogs lacking significant IGFR cross-binding may enhance the safety of insulin replacement therapy in patients with type 2 diabetes mellitus at increased risk of colorectal cancer.


    Related Citations: 
    • The structure of 2zn pig insulin crystal at 1.5 A resolution
      Baker, E.N., Blundell, T.L., Cutfield, J.F., Cutfield, S.M., Dodson, E.J., Dodson, G.G., Hodgkin, D., Isaacs, N.W., Reynolds, C.D.
      (1988) Philos Trans R Soc London,ser B 319: 369
    • Structure of insulin 4-zinc insulin
      Bentley, G., Dodson, E., Dodson, G., Hodgkin, D., Mercola, D.
      (1976) Nature 261: 166
    • Phenol stabilizes more helix in a new symmetrical zinc insulin hexamer
      Derewenda, U., Derewenda, Z., Dodson, G., Reynold, C., Smith, G., Sparks, C., Swenson, D.
      (1989) Nature 338: 594
    • tpward the active conformation of insulin: stereospecific modelation of a structural swith in the B chain
      Hua, Q., Nakagawa, S., Hu, S.Q., Jia, W., Wang, S., Weiss, M.A.
      (2006) J Biol Chem 281: 24900

    Organizational Affiliation

    Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio 44106, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
InsulinAC21N/AMutation(s): 0 
Find proteins for P01308 (Homo sapiens)
Explore P01308 
Go to UniProtKB:  P01308
NIH Common Fund Data Resources
PHAROS  P01308
Protein Feature View
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
InsulinBD30N/AMutation(s): 0 
Find proteins for P01308 (Homo sapiens)
Explore P01308 
Go to UniProtKB:  P01308
NIH Common Fund Data Resources
PHAROS  P01308
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

Download Ideal Coordinates CCD File 
B, D
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
DAB
Query on DAB
A,CL-PEPTIDE LINKINGC4 H10 N2 O2ALA
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.35 Å
  • R-Value Free: 0.228 
  • R-Value Work: 0.198 
  • Space Group: H 3
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 81.841α = 90
b = 81.841β = 90
c = 33.518γ = 120
Software Package:
Software NamePurpose
ADSCdata collection
CNSrefinement
DENZOdata reduction
SCALEPACKdata scaling
CNSphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-08-04
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance