2VT8

Structure of a conserved dimerisation domain within Fbox7 and PI31


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.256 
  • R-Value Work: 0.203 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structure of a Conserved Dimerization Domain within the F-Box Protein Fbxo7 and the Pi31 Proteasome Inhibitor.

Kirk, R.J.Laman, H.Knowles, P.P.Murray-Rust, J.Lomonosov, M.Meziane, E.K.McDonald, N.Q.

(2008) J.Biol.Chem. 283: 22325

  • DOI: 10.1074/jbc.M709900200

  • PubMed Abstract: 
  • F-box proteins are the substrate-recognition components of the Skp1-Cul1-F box protein (SCF) E3 ubiquitin ligases. Here we report a structural relationship between Fbxo7, a component of the SCF(Fbxo7) E3 ligase, and the proteasome inhibitor PI31. SCF ...

    F-box proteins are the substrate-recognition components of the Skp1-Cul1-F box protein (SCF) E3 ubiquitin ligases. Here we report a structural relationship between Fbxo7, a component of the SCF(Fbxo7) E3 ligase, and the proteasome inhibitor PI31. SCF(Fbxo7) is known to catalyze the ubiquitination of hepatoma-up-regulated protein (HURP) and the inhibitor of apoptosis (IAP) protein but also functions as an activator of cyclin D-Cdk6 complexes. We identify PI31 as an Fbxo7.Skp1 binding partner and show that this interaction requires an N-terminal domain present in both proteins that we term the FP (Fbxo7/PI31) domain. The crystal structure of the PI31 FP domain reveals a novel alpha/beta-fold. Biophysical and mutational analyses are used to map regions of the PI31 FP domain mediating homodimerization and required for heterodimerization with Fbxo7.Skp1. Equivalent mutations in Fbxo7 ablate interaction with PI31 and also block Fbxo7 homodimerization. Knockdown of Fbxo7 does not affect PI31 levels arguing against PI31 being a substrate for SCF(Fbxo7). We present a model for FP domain-mediated dimerization of SCF(Fbxo7) and PI31.


    Organizational Affiliation

    Structural Biology Laboratory, London Research Institute, Cancer Research UK, 44 Lincoln's Inn Fields, London WC2A 3PX, United Kingdom.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
PROTEASOME INHIBITOR PI31 SUBUNIT
A, B
153Homo sapiensMutation(s): 1 
Gene Names: PSMF1
Find proteins for Q92530 (Homo sapiens)
Go to Gene View: PSMF1
Go to UniProtKB:  Q92530
Small Molecules
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
CSO
Query on CSO
A, B
L-PEPTIDE LINKINGC3 H7 N O3 SCYS
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.256 
  • R-Value Work: 0.203 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 109.498α = 90.00
b = 45.212β = 111.54
c = 67.279γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
MOLREPphasing
SCALAdata scaling
MOSFLMdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-05-20
    Type: Initial release
  • Version 1.1: 2012-06-06
    Type: Database references, Derived calculations, Non-polymer description, Other, Structure summary, Version format compliance
  • Version 1.2: 2018-03-07
    Type: Database references