3JRM

Crystal structure of archaeal 20S proteasome in complex with mutated P26 activator


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.9 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.201 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural models for interactions between the 20S proteasome and its PAN/19S activators.

Stadtmueller, B.M.Ferrell, K.Whitby, F.G.Heroux, A.Robinson, H.Myszka, D.G.Hill, C.P.

(2010) J.Biol.Chem. 285: 13-17

  • DOI: 10.1074/jbc.C109.070425
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Proteasome activity is regulated by sequestration of its proteolytic centers in a barrel-shaped structure that limits substrate access. Substrates enter the proteasome by means of activator complexes that bind to the end rings of proteasome alpha sub ...

    Proteasome activity is regulated by sequestration of its proteolytic centers in a barrel-shaped structure that limits substrate access. Substrates enter the proteasome by means of activator complexes that bind to the end rings of proteasome alpha subunits and induce opening of an axial entrance/exit pore. The PA26 activator binds in a pocket on the proteasome surface using main chain contacts of its C-terminal residues and uses an internal activation loop to trigger gate opening by repositioning the proteasome Pro-17 reverse turn. Subunits of the unrelated PAN/19S activators bind with their C termini in the same pockets but can induce proteasome gate opening entirely from interactions of their C-terminal peptides, which are reported to cause gate opening by inducing a rocking motion of proteasome alpha subunits rather than by directly contacting the Pro-17 turn. Here we report crystal structures and binding studies of proteasome complexes with PA26 constructs that display modified C-terminal residues, including those corresponding to PAN. These findings suggest that PA26 and PAN/19S C-terminal residues bind superimposably and that both classes of activator induce gate opening by using direct contacts to residues of the proteasome Pro-17 reverse turn. In the case of the PAN and 19S activators, a penultimate tyrosine/phenylalanine residue contacts the proteasome Gly-19 carbonyl oxygen to stabilize the open conformation.


    Organizational Affiliation

    Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah 84112, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Proteasome subunit alpha
A, B, C, D, E, F, G
227Thermoplasma acidophilum (strain ATCC 25905 / DSM 1728 / JCM 9062 / NBRC 15155 / AMRC-C165)Mutation(s): 0 
Gene Names: psmA
EC: 3.4.25.1
Find proteins for P25156 (Thermoplasma acidophilum (strain ATCC 25905 / DSM 1728 / JCM 9062 / NBRC 15155 / AMRC-C165))
Go to UniProtKB:  P25156
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Proteasome subunit beta
H, I, J, K, L, M, N
203Thermoplasma acidophilum (strain ATCC 25905 / DSM 1728 / JCM 9062 / NBRC 15155 / AMRC-C165)Mutation(s): 0 
Gene Names: psmB
EC: 3.4.25.1
Find proteins for P28061 (Thermoplasma acidophilum (strain ATCC 25905 / DSM 1728 / JCM 9062 / NBRC 15155 / AMRC-C165))
Go to UniProtKB:  P28061
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
Proteasome activator protein PA26
O, P, Q, R, S, T, U
228Trypanosoma bruceiMutation(s): 3 
Find proteins for Q9U8G2 (Trypanosoma brucei)
Go to UniProtKB:  Q9U8G2
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.9 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.201 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 255.075α = 90.00
b = 126.363β = 92.54
c = 180.781γ = 90.00
Software Package:
Software NamePurpose
SCALEPACKdata scaling
PDB_EXTRACTdata extraction
DENZOdata reduction
HKL-2000data collection
REFMACphasing
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-11-03
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance
  • Version 1.2: 2017-11-01
    Type: Refinement description