4NIB

Crystal structure of human insulin mutant B20 D-ala, B23 D-ala


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.4 Å
  • R-Value Free: 0.163 
  • R-Value Work: 0.141 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Protective hinge in insulin opens to enable its receptor engagement.

Menting, J.G.Yang, Y.Chan, S.J.Phillips, N.B.Smith, B.J.Whittaker, J.Wickramasinghe, N.P.Whittaker, L.J.Pandyarajan, V.Wan, Z.L.Yadav, S.P.Carroll, J.M.Strokes, N.Roberts, C.T.Ismail-Beigi, F.Milewski, W.Steiner, D.F.Chauhan, V.S.Ward, C.W.Weiss, M.A.Lawrence, M.C.

(2014) Proc.Natl.Acad.Sci.USA 111: E3395-E3404

  • DOI: 10.1073/pnas.1412897111
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Insulin provides a classical model of a globular protein, yet how the hormone changes conformation to engage its receptor has long been enigmatic. Interest has focused on the C-terminal B-chain segment, critical for protective self-assembly in β cell ...

    Insulin provides a classical model of a globular protein, yet how the hormone changes conformation to engage its receptor has long been enigmatic. Interest has focused on the C-terminal B-chain segment, critical for protective self-assembly in β cells and receptor binding at target tissues. Insight may be obtained from truncated "microreceptors" that reconstitute the primary hormone-binding site (α-subunit domains L1 and αCT). We demonstrate that, on microreceptor binding, this segment undergoes concerted hinge-like rotation at its B20-B23 β-turn, coupling reorientation of Phe(B24) to a 60° rotation of the B25-B28 β-strand away from the hormone core to lie antiparallel to the receptor's L1-β2 sheet. Opening of this hinge enables conserved nonpolar side chains (Ile(A2), Val(A3), Val(B12), Phe(B24), and Phe(B25)) to engage the receptor. Restraining the hinge by nonstandard mutagenesis preserves native folding but blocks receptor binding, whereas its engineered opening maintains activity at the price of protein instability and nonnative aggregation. Our findings rationalize properties of clinical mutations in the insulin family and provide a previously unidentified foundation for designing therapeutic analogs. We envisage that a switch between free and receptor-bound conformations of insulin evolved as a solution to conflicting structural determinants of biosynthesis and function.


    Organizational Affiliation

    Structural Biology Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC 3052, Australia;




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Insulin A chain
A
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 chain
B
30Homo sapiensMutation(s): 2 
Gene Names: INS
Find proteins for P01308 (Homo sapiens)
Go to Gene View: INS
Go to UniProtKB:  P01308
Small Molecules
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
DAL
Query on DAL
B
D-PEPTIDE LINKINGC3 H7 N O2

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Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.4 Å
  • R-Value Free: 0.163 
  • R-Value Work: 0.141 
  • Space Group: I 21 3
Unit Cell:
Length (Å)Angle (°)
a = 78.030α = 90.00
b = 78.030β = 90.00
c = 78.030γ = 90.00
Software Package:
Software NamePurpose
PHASERphasing
XDSdata scaling
PHENIXrefinement
Blu-Icedata collection
XDSdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2014-08-27
    Type: Initial release
  • Version 1.1: 2014-09-03
    Type: Database references
  • Version 1.2: 2015-05-06
    Type: Structure summary