Structure of C81R Mutant PCNA Protein Defective in Mismatch Repair

Experimental Data Snapshot

  • Resolution: 3.00 Å
  • R-Value Free: 0.254 
  • R-Value Work: 0.198 
  • R-Value Observed: 0.201 

wwPDB Validation   3D Report Full Report

This is version 1.2 of the entry. See complete history


Distinct structural alterations in proliferating cell nuclear antigen block DNA mismatch repair.

Dieckman, L.M.Boehm, E.M.Hingorani, M.M.Washington, M.T.

(2013) Biochemistry 52: 5611-5619

  • DOI: https://doi.org/10.1021/bi400378e
  • Primary Citation of Related Structures:  
    4L60, 4L6P

  • PubMed Abstract: 

    During DNA replication, mismatches and small loops in the DNA resulting from insertions or deletions are repaired by the mismatch repair (MMR) machinery. Proliferating cell nuclear antigen (PCNA) plays an important role in both mismatch-recognition and resynthesis stages of MMR. Previously, two mutant forms of PCNA were identified that cause defects in MMR with little, if any, other defects. The C22Y mutant PCNA protein completely blocks MutSα-dependent MMR, and the C81R mutant PCNA protein partially blocks both MutSα-dependent and MutSβ-dependent MMR. In order to understand the structural and mechanistic basis by which these two amino acid substitutions in PCNA proteins block MMR, we solved the X-ray crystal structures of both mutant proteins and carried out further biochemical studies. We found that these amino acid substitutions lead to subtle, distinct structural changes in PCNA. The C22Y substitution alters the positions of the α-helices lining the central hole of the PCNA ring, whereas the C81R substitution creates a distortion in an extended loop near the PCNA subunit interface. We conclude that the structural integrity of the α-helices lining the central hole and this loop are both necessary to form productive complexes with MutSα and mismatch-containing DNA.

  • Organizational Affiliation

    Department of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Proliferating cell nuclear antigen256Saccharomyces cerevisiae S288CMutation(s): 1 
Gene Names: POL30YBR0811YBR088C
Find proteins for P15873 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c))
Explore P15873 
Go to UniProtKB:  P15873
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP15873
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 3.00 Å
  • R-Value Free: 0.254 
  • R-Value Work: 0.198 
  • R-Value Observed: 0.201 
  • Space Group: P 21 3
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 121.822α = 90
b = 121.822β = 90
c = 121.822γ = 90
Software Package:
Software NamePurpose
Blu-Icedata collection
PHENIXmodel building
d*TREKdata reduction
d*TREKdata scaling

Structure Validation

View Full Validation Report

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2013-10-02
    Type: Initial release
  • Version 1.1: 2014-11-05
    Changes: Database references
  • Version 1.2: 2023-09-20
    Changes: Data collection, Database references, Refinement description