4OUH

Crystal structure of the FP domain of Human PI31 Proteasome Inhibitor


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.238 
  • R-Value Work: 0.186 

wwPDB Validation 3D Report Full Report


This is version 1.7 of the entry. See complete history

Literature

The FP domains of PI31 and Fbxo7 have the same protein fold but very different modes of protein-protein interaction.

Shang, J.Huang, X.Du, Z.

(2015) J.Biomol.Struct.Dyn. 33: 1528-1538

  • DOI: 10.1080/07391102.2014.963675

  • PubMed Abstract: 
  • Fbxo7 and PI31 contain a conserved FP domain that mediates the homo-/hetero-dimerization of the proteins. The PI31 FP domain may also interact with the F-box motif in Fbxo7. The FP domain-mediated protein-protein interactions are important for the fu ...

    Fbxo7 and PI31 contain a conserved FP domain that mediates the homo-/hetero-dimerization of the proteins. The PI31 FP domain may also interact with the F-box motif in Fbxo7. The FP domain-mediated protein-protein interactions are important for the functions of Fbxo7 and PI31. The crystal structures of the Fbxo7 and PI31 FP domains were determined previously, showing that a C-terminal helix in the Fbxo7 FP domain was not present in the PI31 FP domain. Here, we determine the crystal structure of the PI31 FP domain using a longer protein construct. The structure is comparable to the Fbxo7 FP domain (including the C-terminal helix), indicating that the two FP domains share the same global fold. However, the FP domains also harbor their own characteristic structural features, mainly in the longest loop (which has a largely fixed conformation due to extensive hydrogen bonding and hydrophobic interactions) and the C-terminal end regions. The crystal structures also reveal fundamental differences in the modes of protein-protein interactions mediated by the two FP domains: the PI31 FP domain utilizes either an α interface or β interface for homodimeric interaction, whereas the Fbxo7 FP domain utilizes an αβ interface. We perform modeling studies to show that the domain-specific structural features may dictate specific modes of inter-domain interactions. We propose that a heterodimeric interaction would be mediated by an αβ interface consisting of the α-helical and β-sheet surfaces of the Fbxo7 and PI31 FP domains, respectively. We also discuss the structural/functional significance of various modes of FP domain-mediated protein-protein interactions.


    Organizational Affiliation

    a Department of Chemistry and Biochemistry , Southern Illinois University at Carbondale , Carbondale , IL 62901 , USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Proteasome inhibitor PI31 subunit
A, B, C, D
163Homo sapiensMutation(s): 0 
Gene Names: PSMF1
Find proteins for Q92530 (Homo sapiens)
Go to Gene View: PSMF1
Go to UniProtKB:  Q92530
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.238 
  • R-Value Work: 0.186 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 58.830α = 90.00
b = 97.670β = 90.00
c = 108.220γ = 90.00
Software Package:
Software NamePurpose
PHENIXrefinement
PDB_EXTRACTdata extraction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2015-02-25
    Type: Initial release
  • Version 1.1: 2015-03-04
    Type: Database references
  • Version 1.2: 2015-03-18
    Type: Database references
  • Version 1.3: 2015-04-01
    Type: Database references
  • Version 1.4: 2015-04-08
    Type: Database references
  • Version 1.5: 2015-04-22
    Type: Database references
  • Version 1.6: 2015-04-29
    Type: Database references
  • Version 1.7: 2015-05-20
    Type: Database references