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

  • 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
    • 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
    • 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


    Organizational Affiliation

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




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Insulin
A, C
21Homo sapiensMutation(s): 0 
Gene Names: INS
Find proteins for P01308 (Homo sapiens)
Go to Gene View: INS
Go to UniProtKB:  P01308
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Insulin
B, D
30Homo sapiensMutation(s): 0 
Gene Names: INS
Find proteins for P01308 (Homo sapiens)
Go to Gene View: INS
Go to UniProtKB:  P01308
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

Download SDF File 
Download CCD File 
B, D
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
Modified Residues  2 Unique
IDChainsTypeFormula2D DiagramParent
DAL
Query on DAL
A, C
D-PEPTIDE LINKINGC3 H7 N O2

--

DAB
Query on DAB
A, C
L-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 = 90.00
b = 81.841β = 90.00
c = 33.518γ = 120.00
Software Package:
Software NamePurpose
CNSrefinement
DENZOdata reduction
ADSCdata collection
SCALEPACKdata scaling
CNSphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

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