3L2O

Structure-Based Mechanism of Dimerization-Dependent Ubiquitination by the SCFFbx4 Ubiquitin Ligase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.295 
  • R-Value Work: 0.249 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structural basis of dimerization-dependent ubiquitination by the SCF(Fbx4) ubiquitin ligase.

Li, Y.Hao, B.

(2010) J.Biol.Chem. 285: 13896-13906

  • DOI: 10.1074/jbc.M110.111518

  • PubMed Abstract: 
  • The F-box proteins are the substrate recognition subunits of the SCF (Skp1-Cul1-Rbx1-F- box protein) ubiquitin ligase complexes that control the stability of numerous regulators in eukaryotic cells. Here we show that dimerization of the F-box protein ...

    The F-box proteins are the substrate recognition subunits of the SCF (Skp1-Cul1-Rbx1-F- box protein) ubiquitin ligase complexes that control the stability of numerous regulators in eukaryotic cells. Here we show that dimerization of the F-box protein Fbx4 is essential for SCF(Fbx4) (the superscript denotes the F-box protein) ubiquitination activity toward the telomere regulator Pin2 (also known as TRF1). The crystal structure of Fbx4 in complex with an adaptor protein Skp1 reveals an antiparallel dimer configuration in which the linker domain of Fbx4 interacts with the C-terminal substrate-binding domain of the other protomer, whereas the C-terminal domain of the protein adopts a compact alpha/beta fold distinct from those of known F-box proteins. Biochemical studies indicate that both the N-terminal domain and a loop connecting the linker and C-terminal domain of Fbx4 are critical for the dimerization and activation of the protein. Our findings provide a framework for understanding the role of F-box dimerization in the SCF-mediated ubiquitination reaction.


    Organizational Affiliation

    Department of Molecular, Microbial, and Structural Biology, University of Connecticut Health Center, Farmington, Connecticut 06030, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
S-phase kinase-associated protein 1
A
149Homo sapiensMutation(s): 1 
Gene Names: SKP1 (EMC19, OCP2, SKP1A, TCEB1L)
Find proteins for P63208 (Homo sapiens)
Go to Gene View: SKP1
Go to UniProtKB:  P63208
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
F-box only protein 4
B
312Homo sapiensMutation(s): 0 
Gene Names: FBXO4 (FBX4)
Find proteins for Q9UKT5 (Homo sapiens)
Go to Gene View: FBXO4
Go to UniProtKB:  Q9UKT5
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.295 
  • R-Value Work: 0.249 
  • Space Group: P 31 2 1
Unit Cell:
Length (Å)Angle (°)
a = 92.194α = 90.00
b = 92.194β = 90.00
c = 148.068γ = 120.00
Software Package:
Software NamePurpose
HKL-2000data collection
SHELXSphasing
REFMACrefinement
HKL-2000data scaling
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2009-12-15 
  • Released Date: 2010-02-23 
  • Deposition Author(s): Li, Y., Hao, B.

Revision History 

  • Version 1.0: 2010-02-23
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Advisory, Version format compliance