6I0O

Structure of human IMP dehydrogenase, isoform 2, bound to GTP


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.623 Å
  • R-Value Free: 0.244 
  • R-Value Work: 0.219 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

A Nucleotide-Dependent Conformational Switch Controls the Polymerization of Human IMP Dehydrogenases to Modulate their Catalytic Activity.

Fernandez-Justel, D.Nunez, R.Martin-Benito, J.Jimeno, D.Gonzalez-Lopez, A.Soriano, E.M.Revuelta, J.L.Buey, R.M.

(2019) J. Mol. Biol. 431: 956-969

  • DOI: 10.1016/j.jmb.2019.01.020
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • IMP dehydrogenase (IMPDH) catalyzes the rate-limiting step in the de novo GTP biosynthetic pathway and plays essential roles in cell proliferation. As a clinical target, IMPDH has been studied for decades but it has only been within the last years th ...

    IMP dehydrogenase (IMPDH) catalyzes the rate-limiting step in the de novo GTP biosynthetic pathway and plays essential roles in cell proliferation. As a clinical target, IMPDH has been studied for decades but it has only been within the last years that we are starting to understand the complexity of the mechanisms of its physiological regulation. Here, we report structural and functional insights into how adenine and guanine nucleotides control a conformational switch that modulates the assembly of the two human IMPDH enzymes into cytoophidia and allosterically regulates their catalytic activity. In vitro reconstituted micron-length cytoophidia-like structures show catalytic activity comparable to unassembled IMPDH but, in turn, are more resistant to GTP/GDP allosteric inhibition. Therefore, IMPDH cytoophidia formation facilitates the accumulation of high levels of guanine nucleotides when the cell requires it. Finally, we demonstrate that most of the IMPDH retinopathy-associated mutations abrogate GTP/GDP-induced allosteric inhibition and alter cytoophidia dynamics.


    Organizational Affiliation

    Metabolic Engineering Group, Dpto. Microbiología y Genética. Universidad de Salamanca, Campus Miguel de Unamuno, 37007, Salamanca, Spain.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Inosine-5'-monophosphate dehydrogenase 2
A, B
517Homo sapiensMutation(s): 0 
Gene Names: IMPDH2 (IMPD2)
EC: 1.1.1.205
Find proteins for P12268 (Homo sapiens)
Go to Gene View: IMPDH2
Go to UniProtKB:  P12268
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download SDF File 
Download CCD File 
A, B
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
GTP
Query on GTP

Download SDF File 
Download CCD File 
A, B
GUANOSINE-5'-TRIPHOSPHATE
C10 H16 N5 O14 P3
XKMLYUALXHKNFT-UUOKFMHZSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.623 Å
  • R-Value Free: 0.244 
  • R-Value Work: 0.219 
  • Space Group: I 4 2 2
Unit Cell:
Length (Å)Angle (°)
a = 134.119α = 90.00
b = 134.119β = 90.00
c = 325.703γ = 90.00
Software Package:
Software NamePurpose
STARANISOdata scaling
XDSdata reduction
PHASERphasing
PHENIXrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
SpainBFU2016-79237-P

Revision History 

  • Version 1.0: 2019-01-30
    Type: Initial release
  • Version 1.1: 2019-02-20
    Type: Advisory, Data collection, Derived calculations
  • Version 1.2: 2019-03-06
    Type: Data collection, Database references