5WE1 | pdb_00005we1

Structural Basis for Shelterin Bridge Assembly

• PDB DOI: https://doi.org/10.2210/pdb5WE1/pdb

• Classification: GENE REGULATION
• Organism(s): Schizosaccharomyces pombe 972h-
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2017-07-06 Released: 2017-12-20 
• Deposition Author(s): Kim, J.-K., Liu, J., Hu, X., Yu, C., Roskamp, K., Sankaran, B., Huang, L., Komives, E.-A., Qiao, F.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.20 Å
• R-Value Free: 
  0.317 (Depositor), 0.317 (DCC) 
• R-Value Work: 
  0.266 (Depositor), 0.282 (DCC) 
• R-Value Observed: 
  0.269 (Depositor) 

Starting Model: experimental

Literature

Structural Basis for Shelterin Bridge Assembly.

Kim, J.K., Liu, J., Hu, X., Yu, C., Roskamp, K., Sankaran, B., Huang, L., Komives, E.A., Qiao, F.

(2017) Mol Cell 68: 698-714.e5

• PubMed: 29149597 
• DOI: https://doi.org/10.1016/j.molcel.2017.10.032
• Primary Citation Related Structures: 
  5WE0, 5WE1, 5WE2


• PubMed Abstract: 
  

  Telomere elongation through telomerase enables chromosome survival during cellular proliferation. The conserved multifunctional shelterin complex associates with telomeres to coordinate multiple telomere activities, including telomere elongation by telomerase. Similar to the human shelterin, fission yeast shelterin is composed of telomeric sequence-specific double- and single-stranded DNA-binding proteins, Taz1 and Pot1, respectively, bridged by Rap1, Poz1, and Tpz1. Here, we report the crystal structure of the fission yeast Tpz1 ^475-508 -Poz1-Rap1 ^467-496 complex that provides the structural basis for shelterin bridge assembly. Biochemical analyses reveal that shelterin bridge assembly is a hierarchical process in which Tpz1 binding to Poz1 elicits structural changes in Poz1, allosterically promoting Rap1 binding to Poz1. Perturbation of the cooperative Tpz1-Poz1-Rap1 assembly through mutation of the "conformational trigger" in Poz1 leads to unregulated telomere lengthening. Furthermore, we find that the human shelterin counterparts TPP1-TIN2-TRF2 also assemble hierarchically, indicating cooperativity as a conserved driving force for shelterin assembly.

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Organizational Affiliation: 
• Department of Biological Chemistry, School of Medicine, University of California, Irvine, Irvine, CA 92697-1700, USA.
Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, Irvine, CA 92697-4560, USA.
Department of Chemistry, University of California, Irvine, Irvine, CA 92697-2025, USA.
Berkeley Center for Structural Biology, Physical Biosciences Division, Lawrence Berkeley Laboratory, Berkeley, CA 94720, USA.
Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093-0378, USA.
Department of Biological Chemistry, School of Medicine, University of California, Irvine, Irvine, CA 92697-1700, USA. Electronic address: [e-mail].

Biological Assembly 1  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Hetero 4-mer - A2B2 

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

Biological Assembly Evidence: gel filtration

Macromolecule Content 

• Total Structure Weight: 58.69 kDa 
• Atom Count: 3,513 
• Modeled Residue Count: 417 
• Deposited Residue Count: 494 
• Unique protein chains: 2

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Protection of telomeres protein poz1,Protection of telomeres protein poz1	A, C	214	Schizosaccharomyces pombe 972h-	Mutation(s): 0  Gene Names: poz1, SPAC19G12.13c
UniProt
Find proteins for O13852 (Schizosaccharomyces pombe (strain 972 / ATCC 24843)) Explore O13852  Go to UniProtKB:  O13852

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Protection of telomeres protein tpz1	B, D	33	Schizosaccharomyces pombe 972h-	Mutation(s): 0  Gene Names: tpz1, mug169, SPAC6F6.16c, SPAC6F6.18c
UniProt
Find proteins for O14246 (Schizosaccharomyces pombe (strain 972 / ATCC 24843)) Explore O14246  Go to UniProtKB:  O14246

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
ZN	E [auth A], F [auth C]	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.20 Å
• R-Value Free:  0.317 (Depositor), 0.317 (DCC) 
• R-Value Work:  0.266 (Depositor), 0.282 (DCC) 
• R-Value Observed: 0.269 (Depositor) 

Space Group: P 3₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 66.11	α = 90
b = 66.11	β = 90
c = 123.16	γ = 120

Software Package:

Software Name	Purpose
PHENIX	refinement
Coot	model building
PHENIX	phasing
MOSFLM	data processing
MOSFLM	data reduction
SCALA	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2017-12-20 
Deposition Author(s): Kim, J.-K., Liu, J., Hu, X., Yu, C., Roskamp, K., Sankaran, B., Huang, L., Komives, E.-A., Qiao, F.

Revision History  

• Version 1.0: 2017-12-20
  Type: Initial release
  
• Version 1.1: 2023-10-04
  Changes: Data collection, Database references, Derived calculations, Refinement description
• Version 1.2: 2024-11-20
  Changes: Structure summary