5C9H

Structural Basis of Template Boundary Definition in Tetrahymena Telomerase

• PDB DOI: https://doi.org/10.2210/pdb5C9H/pdb
• NAKB: 5C9H

• Classification: RNA binding protein/RNA
• Organism(s): Tetrahymena thermophila
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2015-06-26 Released: 2015-10-14 
• Deposition Author(s): Jansson, L.I., Akiyama, B.M., Ooms, A., Lu, C., Rubin, S.M., Stone, M.D.
• Funding Organization(s): National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.00 Å
• R-Value Free: 0.290 
• R-Value Work: 0.239 
• R-Value Observed: 0.244 

Starting Model: experimental

Literature

Structural basis of template-boundary definition in Tetrahymena telomerase.

Jansson, L.I., Akiyama, B.M., Ooms, A., Lu, C., Rubin, S.M., Stone, M.D.

(2015) Nat Struct Mol Biol 22: 883-888

• PubMed: 26436828 
• DOI: https://doi.org/10.1038/nsmb.3101
• Primary Citation of Related Structures:  
  5C9H


• PubMed Abstract: 
  

  Telomerase is required to maintain repetitive G-rich telomeric DNA sequences at chromosome ends. To do so, the telomerase reverse transcriptase (TERT) subunit reiteratively uses a small region of the integral telomerase RNA (TER) as a template. An essential feature of telomerase catalysis is the strict definition of the template boundary to determine the precise TER nucleotides to be reverse transcribed by TERT. We report the 3-Å crystal structure of the Tetrahymena TERT RNA-binding domain (tTRBD) bound to the template boundary element (TBE) of TER. tTRBD is wedged into the base of the TBE RNA stem-loop, and each of the flanking RNA strands wraps around opposite sides of the protein domain. The structure illustrates how the tTRBD establishes the template boundary by positioning the TBE at the correct distance from the TERT active site to prohibit copying of nontemplate nucleotides.

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Organizational Affiliation: 

Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California, USA.

Biological Assembly 1  

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

Biological assembly 1 assigned by authors and generated by PISA (software)

Biological Assembly 2  

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

Biological assembly 2 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 89.82 kDa 
• Atom Count: 4,793 
• Modelled Residue Count: 513 
• Deposited Residue Count: 658 
• Unique protein chains: 1
• Unique nucleic acid chains: 2

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Telomerase reverse transcriptase	A, B	303	Tetrahymena thermophila	Mutation(s): 0  Gene Names: TERT EC: 2.7.7.49
UniProt
Find proteins for O77448 (Tetrahymena thermophila (strain SB210)) Explore O77448  Go to UniProtKB:  O77448

Entity ID: 2
Molecule	Chains	Length	Organism	Image
RNA (5'-R(P*AP*GP*AP*AP*CP*UP*GP*UP*CP*A)-3')	C [auth D], E	13	Tetrahymena thermophila

Entity ID: 3
Molecule	Chains	Length	Organism	Image
RNA (5'-R(P*UP*CP*AP*UP*UP*CP*AP*GP*UP*UP*CP*U)-3')	D [auth C], F [auth G]	13	Tetrahymena thermophila

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
MG	G [auth C], H [auth G]	MAGNESIUM ION Mg JLVVSXFLKOJNIY-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.00 Å
• R-Value Free: 0.290 
• R-Value Work: 0.239 
• R-Value Observed: 0.244 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 58.53	α = 90
b = 117.77	β = 90
c = 131.18	γ = 90

Software Package:

Software Name	Purpose
PHENIX	refinement
MOSFLM	data reduction
SCALA	data scaling
PHASER	phasing

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2015-10-14 
Deposition Author(s): Jansson, L.I., Akiyama, B.M., Ooms, A., Lu, C., Rubin, S.M., Stone, M.D.

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Funding Organization	Location	Grant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)	United States	R01 GM095850
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)	United States	T32GM008646-16

Revision History  

• Version 1.0: 2015-10-14
  Type: Initial release
  
• Version 1.1: 2015-12-02
  Changes: Database references
• Version 1.2: 2017-09-20
  Changes: Author supporting evidence, Derived calculations
• Version 1.3: 2019-12-25
  Changes: Author supporting evidence
• Version 1.4: 2023-09-27
  Changes: Data collection, Database references, Derived calculations, Refinement description