3OFI

Crystal structure of human insulin-degrading enzyme in complex with ubiquitin


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.35 Å
  • R-Value Free: 0.240 
  • R-Value Work: 0.210 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Ubiquitin is a novel substrate for human insulin-degrading enzyme.

Ralat, L.A.Kalas, V.Zheng, Z.Goldman, R.D.Sosnick, T.R.Tang, W.J.

(2011) J.Mol.Biol. 406: 454-466

  • DOI: 10.1016/j.jmb.2010.12.026

  • PubMed Abstract: 
  • Insulin-degrading enzyme (IDE) can degrade insulin and amyloid-β, peptides involved in diabetes and Alzheimer's disease, respectively. IDE selects its substrates based on size, charge, and flexibility. From these criteria, we predict that IDE can cle ...

    Insulin-degrading enzyme (IDE) can degrade insulin and amyloid-β, peptides involved in diabetes and Alzheimer's disease, respectively. IDE selects its substrates based on size, charge, and flexibility. From these criteria, we predict that IDE can cleave and inactivate ubiquitin (Ub). Here, we show that IDE cleaves Ub in a biphasic manner, first, by rapidly removing the two C-terminal glycines (k(cat)=2 s(-1)) followed by a slow cleavage between residues 72 and 73 (k(cat)=0.07 s(-1)), thereby producing the inactive 1-74 fragment of Ub (Ub1-74) and 1-72 fragment of Ub (Ub1-72). IDE is a ubiquitously expressed cytosolic protein, where monomeric Ub is also present. Thus, Ub degradation by IDE should be regulated. IDE is known to bind the cytoplasmic intermediate filament protein nestin with high affinity. We found that nestin potently inhibits the cleavage of Ub by IDE. In addition, Ub1-72 has a markedly increased affinity for IDE (∼90-fold). Thus, the association of IDE with cellular regulators and product inhibition by Ub1-72 can prevent inadvertent proteolysis of cellular Ub by IDE. Ub is a highly stable protein. However, IDE instead prefers to degrade peptides with high intrinsic flexibility. Indeed, we demonstrate that IDE is exquisitely sensitive to Ub stability. Mutations that only mildly destabilize Ub (ΔΔG<0.6 kcal/mol) render IDE hypersensitive to Ub with rate enhancements greater than 12-fold. The Ub-bound IDE structure and IDE mutants reveal that the interaction of the exosite with the N-terminus of Ub guides the unfolding of Ub, allowing its sequential cleavages. Together, our studies link the control of Ub clearance with IDE.


    Organizational Affiliation

    Ben May Department for Cancer Research, The University of Chicago, 929 East 57th Street, Chicago, IL 60637, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Insulin-degrading enzyme
A, B
990Homo sapiensMutation(s): 14 
Gene Names: IDE
EC: 3.4.24.56
Find proteins for P14735 (Homo sapiens)
Go to Gene View: IDE
Go to UniProtKB:  P14735
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Ubiquitin
C, D
76Homo sapiensMutation(s): 0 
Gene Names: UBC
Find proteins for P0CG48 (Homo sapiens)
Go to Gene View: UBC
Go to UniProtKB:  P0CG48
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

Download SDF File 
Download CCD File 
A, B
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
DIO
Query on DIO

Download SDF File 
Download CCD File 
A, B
1,4-DIETHYLENE DIOXIDE
C4 H8 O2
RYHBNJHYFVUHQT-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.35 Å
  • R-Value Free: 0.240 
  • R-Value Work: 0.210 
  • Space Group: P 65
Unit Cell:
Length (Å)Angle (°)
a = 262.943α = 90.00
b = 262.943β = 90.00
c = 90.968γ = 120.00
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
REFMACrefinement
PDB_EXTRACTdata extraction
CNSrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2010-09-08
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance
  • Version 1.2: 2017-11-08
    Type: Refinement description