Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

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

Macromolecule Content

• Total Structure Weight: 17127.65 
• Atom Count: 1206 
• Residue Count: 142 
• Unique protein chains: 1

4G79

Structure a C. elegans SAS-6 variant

• DOI: 10.2210/pdb4G79/pdb

• Classification: STRUCTURAL PROTEIN
• Organism(s): Caenorhabditis elegans
• Expression System: Escherichia coli BL21(DE3)


• Deposited: 2012-07-20 Released: 2013-06-19 
• Deposition Author(s): Erat, M.C., Vakonakis, I.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.8 Å
• R-Value Free: 0.210 
• R-Value Work: 0.197 

Literature

Caenorhabditis elegans centriolar protein SAS-6 forms a spiral that is consistent with imparting a ninefold symmetry.

Hilbert, M., Erat, M.C., Hachet, V., Guichard, P., Blank, I.D., Fluckiger, I., Slater, L., Lowe, E.D., Hatzopoulos, G.N., Steinmetz, M.O., Gonczy, P., Vakonakis, I.

(2013) Proc.Natl.Acad.Sci.USA 110: 11373-11378

• PubMed: 23798409 
• DOI: 10.1073/pnas.1302721110
• Primary Citation of Related Structures:  
  4GFC, 4GFA, 4GEX, 4GEU
• Also Cited By: 4TPZ


• PubMed Abstract: 
  

Centrioles are evolutionary conserved organelles that give rise to cilia and flagella as well as centrosomes. Centrioles display a characteristic ninefold symmetry imposed by the spindle assembly abnormal protein 6 (SAS-6) family. SAS-6 from Chlamydomonas reinhardtii and Danio rerio was shown to form ninefold symmetric, ring-shaped oligomers in vitro that were similar to the cartwheels observed in vivo during early steps of centriole assembly in most species. Here, we report crystallographic and EM analyses showing that, instead, Caenorhabotis elegans SAS-6 self-assembles into a spiral arrangement. Remarkably, we find that this spiral arrangement is also consistent with ninefold symmetry, suggesting that two distinct SAS-6 oligomerization architectures can direct the same output symmetry. Sequence analysis suggests that SAS-6 spirals are restricted to specific nematodes. This oligomeric arrangement may provide a structural basis for the presence of a central tube instead of a cartwheel during centriole assembly in these species.

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Organizational Affiliation: 

Laboratory of Biomolecular Research (LBR), Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
Spindle assembly abnormal protein 6	A	142	Caenorhabditis elegans	Mutation(s): 0  Gene Names: sas-6
Find proteins for O62479 (Caenorhabditis elegans) Go to UniProtKB:  O62479

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram & Interactions
GOL	A	GLYCEROL GLYCERIN; PROPANE-1,2,3-TRIOL C3 H8 O3 PEDCQBHIVMGVHV-UHFFFAOYSA-N
PG4	A	TETRAETHYLENE GLYCOL C8 H18 O5 UWHCKJMYHZGTIT-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.8 Å
• R-Value Free: 0.210 
• R-Value Work: 0.197 
• Space Group: I 2 2 2

Unit Cell:

Length (Å)	Angle (°)
a = 69.330	α = 90.00
b = 73.370	β = 90.00
c = 79.330	γ = 90.00

Software Package:

Software Name	Purpose
GNDclient	data collection
BUSTER	refinement
SCALA	data scaling
PHASER	phasing
MOSFLM	data reduction

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2012-07-20 
• Released Date: 2013-06-19 
• Deposition Author(s): Erat, M.C., Vakonakis, I.

Revision History 

• Version 1.0: 2013-06-19
  Type: Initial release
• Version 1.1: 2013-07-17
  Type: Database references
• Version 1.2: 2013-07-24
  Type: Database references
• Version 1.3: 2017-08-16
  Type: Refinement description, Source and taxonomy