Biological Assembly 1  

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

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

Biological Assembly Evidence: gel filtration

Macromolecule Content

• Total Structure Weight: 14.24 kDa 
• Atom Count: 1,120 
• Modelled Residue Count: 123 
• Deposited Residue Count: 123 
• Unique protein chains: 1

 6UY9

Crystal structure of the STAC3 tandem SH3 domains - P269R, W284S

• PDB DOI: 10.2210/pdb6UY9/pdb

• Classification: PROTEIN BINDING
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): Yes 


• Deposited: 2019-11-12 Released: 2020-06-17 
• Deposition Author(s): Rufenach, B., Van Petegem, F.
• Funding Organization(s): Canadian Institutes of Health Research (CIHR)

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.60 Å
• R-Value Free: 0.209 
• R-Value Work: 0.182 
• R-Value Observed: 0.183 

Literature

Multiple Sequence Variants in STAC3 Affect Interactions with CaV1.1 and Excitation-Contraction Coupling.

Rufenach, B., Christy, D., Flucher, B.E., Bui, J.M., Gsponer, J., Campiglio, M., Van Petegem, F.

(2020) Structure 28: 922

• PubMed: 32492370 
• DOI: 10.1016/j.str.2020.05.005
• Primary Citation of Related Structures:  
  6UY7, 6UY8, 6UY9


• PubMed Abstract: 
  

STAC3 is a soluble protein essential for skeletal muscle excitation-contraction (EC) coupling. Through its tandem SH3 domains, it interacts with the cytosolic II-III loop of the skeletal muscle voltage-gated calcium channel. STAC3 is the target for a mutation (W284S) that causes Native American myopathy, but multiple other sequence variants have been reported. Here, we report a crystal structure of the human STAC3 tandem SH3 domains. We analyzed the effect of five disease-associated variants, spread over both SH3 domains, on their ability to bind to the Ca _V 1.1 II-III loop and on muscle EC coupling. In addition to W284S, we find the F295L and K329N variants to affect both binding and EC coupling. The ability of the K329N variant, located in the second SH3 domain, to affect the interaction highlights the importance of both SH3 domains in association with Ca _V 1.1. Our results suggest that multiple STAC3 variants may cause myopathy.

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Organizational Affiliation: 

Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada. Electronic address: [e-mail].

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
SH3 and cysteine-rich domain-containing protein 3	A	123	Homo sapiens	Mutation(s): 2  Gene Names: STAC3
UniProt & NIH Common Fund Data Resources
Find proteins for Q96MF2 (Homo sapiens) Explore Q96MF2  Go to UniProtKB:  Q96MF2
PHAROS:  Q96MF2

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
EDO	B [auth A], C [auth A]	1,2-ETHANEDIOL C2 H6 O2 LYCAIKOWRPUZTN-UHFFFAOYSA-N
NA	D [auth A]	SODIUM ION Na FKNQFGJONOIPTF-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.60 Å
• R-Value Free: 0.209 
• R-Value Work: 0.182 
• R-Value Observed: 0.183 
• Space Group: C 1 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 84.032	α = 90
b = 29.331	β = 129.62
c = 57.143	γ = 90

Software Package:

Software Name	Purpose
HKL-2000	data scaling
PHENIX	refinement
PDB_EXTRACT	data extraction
HKL-2000	data reduction
PHASER	phasing

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2020-06-17 
Deposition Author(s): Rufenach, B., Van Petegem, F.

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Funding Organization	Location	Grant Number
Canadian Institutes of Health Research (CIHR)	Canada	PJT-159601

Revision History  

• Version 1.0: 2020-06-17
  Type: Initial release
  
• Version 1.1: 2020-08-19
  Changes: Database references