2M9H | pdb_00002m9h

DNA-binding domain of T. brucei telomeric protein tbTRF

• PDB DOI: https://doi.org/10.2210/pdb2M9H/pdb
• BMRB: 19294

• Classification: DNA BINDING PROTEIN
• Organism(s): Trypanosoma brucei
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2013-06-09 Released: 2014-07-16 
• Deposition Author(s): Li, X., Ye, F., Zhang, M., Zhao, Y.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Calculated: 20 
• Conformers Submitted: 20 
• Selection Criteria: back calculated data agree with experimental NOESY spectrum 

Literature

Suppression of subtelomeric VSG switching by Trypanosoma brucei TRF requires its TTAGGG repeat-binding activity.

Jehi, S.E., Li, X., Sandhu, R., Ye, F., Benmerzouga, I., Zhang, M., Zhao, Y., Li, B.

(2014) Nucleic Acids Res 42: 12899-12911

• PubMed: 25313155 
• DOI: https://doi.org/10.1093/nar/gku942
• Primary Citation Related Structures: 
  2M9H


• PubMed Abstract: 
  

  Trypanosoma brucei causes human African trypanosomiasis and regularly switches its major surface antigen, VSG, in the bloodstream of its mammalian host to evade the host immune response. VSGs are expressed exclusively from subtelomeric loci, and we have previously shown that telomere proteins TbTIF2 and TbRAP1 play important roles in VSG switching and VSG silencing regulation, respectively. We now discover that the telomere duplex DNA-binding factor, TbTRF, also plays a critical role in VSG switching regulation, as a transient depletion of TbTRF leads to significantly more VSG switching events. We solved the NMR structure of the DNA-binding Myb domain of TbTRF, which folds into a canonical helix-loop-helix structure that is conserved to the Myb domains of mammalian TRF proteins. The TbTRF Myb domain tolerates well the bulky J base in T. brucei telomere DNA, and the DNA-binding affinity of TbTRF is not affected by the presence of J both in vitro and in vivo. In addition, we find that point mutations in TbTRF Myb that significantly reduced its in vivo telomere DNA-binding affinity also led to significantly increased VSG switching frequencies, indicating that the telomere DNA-binding activity is critical for TbTRF's role in VSG switching regulation.

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Organizational Affiliation: 
• Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, Cleveland State University, Cleveland, OH 44115, USA.
Department of Applied Biology and Chemical Technology, State Key Laboratory of Chirosciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P. R. China The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, P.R. China.
Division of Life Science, State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, P. R. China.
Department of Applied Biology and Chemical Technology, State Key Laboratory of Chirosciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P. R. China [e-mail].
Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, Cleveland State University, Cleveland, OH 44115, USA Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH 44106, USA Department of Molecular Genetics, Cleveland Clinic Lerner Research Institute, Cleveland, OH 44195, USA The Rockefeller University, New York, NY 10065, USA [e-mail].

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content 

• Total Structure Weight: 12.05 kDa 
• Atom Count: 852 
• Modeled Residue Count: 106 
• Deposited Residue Count: 106 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
TTAGGG binding factor	A	106	Trypanosoma brucei	Mutation(s): 0  Gene Names: TRF
UniProt
Find proteins for Q4VHG6 (Trypanosoma brucei) Explore Q4VHG6  Go to UniProtKB:  Q4VHG6

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Calculated: 20 
• Conformers Submitted: 20 
• Selection Criteria: back calculated data agree with experimental NOESY spectrum 

Structure Validation

Entry History 

Deposition Data

• Released Date: 2014-07-16 
Deposition Author(s): Li, X., Ye, F., Zhang, M., Zhao, Y.

Revision History  

• Version 1.0: 2014-07-16
  Type: Initial release
  
• Version 1.1: 2014-11-26
  Changes: Database references
• Version 1.2: 2023-06-14
  Changes: Database references, Other
• Version 1.3: 2024-05-15
  Changes: Data collection, Database references