3KF8

Crystal structure of C. tropicalis Stn1-ten1 complex


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.40 Å
  • R-Value Free: 0.265 
  • R-Value Work: 0.228 
  • R-Value Observed: 0.228 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Stn1-Ten1 is an Rpa2-Rpa3-like complex at telomeres.

Sun, J.Yu, E.Y.Yang, Y.Confer, L.A.Sun, S.H.Wan, K.Lue, N.F.Lei, M.

(2009) Genes Dev 23: 2900-2914

  • DOI: https://doi.org/10.1101/gad.1851909
  • Primary Citation of Related Structures:  
    3KEY, 3KF6, 3KF8

  • PubMed Abstract: 

    In budding yeast, Cdc13, Stn1, and Ten1 form a heterotrimeric complex (CST) that is essential for telomere protection and maintenance. Previous bioinformatics analysis revealed a putative oligonucleotide/oligosaccharide-binding (OB) fold at the N terminus of Stn1 (Stn1N) that shows limited sequence similarity to the OB fold of Rpa2, a subunit of the eukaryotic ssDNA-binding protein complex replication protein A (RPA). Here we present functional and structural analyses of Stn1 and Ten1 from multiple budding and fission yeast. The crystal structure of the Candida tropicalis Stn1N complexed with Ten1 demonstrates an Rpa2N-Rpa3-like complex. In both structures, the OB folds of the two components pack against each other through interactions between two C-terminal helices. The structure of the C-terminal domain of Saccharomyces cerevisiae Stn1 (Stn1C) was found to comprise two related winged helix-turn-helix (WH) motifs, one of which is most similar to the WH motif at the C terminus of Rpa2, again supporting the notion that Stn1 resembles Rpa2. The crystal structure of the fission yeast Schizosaccharomyces pombe Stn1N-Ten1 complex exhibits a virtually identical architecture as the C. tropicalis Stn1N-Ten1. Functional analyses of the Candida albicans Stn1 and Ten1 proteins revealed critical roles for these proteins in suppressing aberrant telomerase and recombination activities at telomeres. Mutations that disrupt the Stn1-Ten1 interaction induce telomere uncapping and abolish the telomere localization of Ten1. Collectively, our structural and functional studies illustrate that, instead of being confined to budding yeast telomeres, the CST complex may represent an evolutionarily conserved RPA-like telomeric complex at the 3' overhangs that works in parallel with or instead of the well-characterized POT1-TPP1/TEBPalpha-beta complex.


  • Organizational Affiliation

    Howard Hughes Medical Institute, University of Michigan Medical School, Ann Arbor, Michigan 48109, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Protein stn1
A, C
220Candida tropicalis MYA-3404Mutation(s): 0 
Gene Names: CTRG_01841
UniProt
Find proteins for C5M7K9 (Candida tropicalis (strain ATCC MYA-3404 / T1))
Explore C5M7K9 
Go to UniProtKB:  C5M7K9
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupC5M7K9
Sequence Annotations
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
Protein ten1
B, D
123Candida tropicalis MYA-3404Mutation(s): 0 
Gene Names: CTRG_00988
UniProt
Find proteins for C5M4J8 (Candida tropicalis (strain ATCC MYA-3404 / T1))
Explore C5M4J8 
Go to UniProtKB:  C5M4J8
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupC5M4J8
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.40 Å
  • R-Value Free: 0.265 
  • R-Value Work: 0.228 
  • R-Value Observed: 0.228 
  • Space Group: P 41 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 92.072α = 90
b = 92.072β = 90
c = 200.909γ = 90
Software Package:
Software NamePurpose
MAR345data collection
SHARPphasing
CNSrefinement
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2009-12-22
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 1.2: 2017-11-01
    Changes: Refinement description
  • Version 1.3: 2024-02-21
    Changes: Data collection, Database references