5MX5

Mouse PA28alpha-beta


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.9 Å
  • R-Value Free: 0.272 
  • R-Value Work: 0.243 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

The Mammalian Proteasome Activator PA28 Forms an Asymmetric alpha 4 beta 3 Complex.

Huber, E.M.Groll, M.

(2017) Structure 25: 1473-1480.e3

  • DOI: 10.1016/j.str.2017.07.013
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The heptameric proteasome activator (PA) 28αβ is known to modulate class I antigen processing by docking onto 20S proteasome core particles (CPs). The exact stoichiometry and arrangement of its α and β subunits, however, is still controversial. Here ...

    The heptameric proteasome activator (PA) 28αβ is known to modulate class I antigen processing by docking onto 20S proteasome core particles (CPs). The exact stoichiometry and arrangement of its α and β subunits, however, is still controversial. Here we analyzed murine PA28 complexes regarding structure and assembly. Strikingly, PA28α, PA28β, and PA28αβ preparations form heptamers, but solely PA28α and PA28αβ associate with CPs. Co-expression of α and β yields one unique PA28αβ species with an unchangeable subunit composition. Structural data on PA28α, PA28β, and PA28αβ up to 2.9 Å resolution reveal a PA28α4β3 complex with an alternating subunit arrangement and a single α-α interface. Differential scanning fluorimetry experiments and activity assays classify PA28α4β3 as most stable and most active, indicating that this assembly might represent the physiologically relevant species. Together, our data resolve subunit composition and arrangement of PA28αβ and clarify how an asymmetric heptamer can be assembled from two highly homologous subunits.


    Organizational Affiliation

    Center for Integrated Protein Science, Department Chemie, Lehrstuhl für Biochemie, Technische Universität München, Lichtenbergstrasse 4, 85748 Garching, Germany. Electronic address: eva.huber@tum.de.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Proteasome activator complex subunit 1
A, C, E, G, H, J, L, N
249Mus musculusMutation(s): 0 
Gene Names: Psme1
Find proteins for P97371 (Mus musculus)
Go to UniProtKB:  P97371
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Proteasome activator complex subunit 2
B, D, F, I, K, M
239Mus musculusMutation(s): 0 
Gene Names: Psme2 (Pa28b1)
Find proteins for P97372 (Mus musculus)
Go to UniProtKB:  P97372
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PO4
Query on PO4

Download SDF File 
Download CCD File 
E, G, N
PHOSPHATE ION
O4 P
NBIIXXVUZAFLBC-UHFFFAOYSA-K
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.9 Å
  • R-Value Free: 0.272 
  • R-Value Work: 0.243 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 126.090α = 90.00
b = 137.380β = 104.44
c = 136.420γ = 90.00
Software Package:
Software NamePurpose
PHASERphasing
XSCALEdata scaling
XDSdata reduction
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data

  • Deposited Date: 2017-01-20 
  • Released Date: 2017-09-13 
  • Deposition Author(s): Huber, E.M., Groll, M.

Funding OrganizationLocationGrant Number
German Research FoundationGermanySFB1035

Revision History 

  • Version 1.0: 2017-09-13
    Type: Initial release
  • Version 1.1: 2017-10-18
    Type: Database references