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 PQS (software)

Macromolecule Content

• Total Structure Weight: 27028.34 
• Atom Count: 1574 
• Residue Count: 222 
• Unique protein chains: 1

1V1F

Structure of the Arabidopsis thaliana SOS3 complexed with Calcium(II) and Manganese(II) ions

• DOI: 10.2210/pdb1V1F/pdb

• Classification: SIGNALLING PROTEIN
• Organism(s): Arabidopsis thaliana
• Expression System: Escherichia coli BL21(DE3)


• Deposited: 2004-04-15 Released: 2005-01-19 
• Deposition Author(s): Sanchez-Barrena, M.J., Martinez-Ripoll, M., Zhu, J.K., Albert, A.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3 Å
• R-Value Free: 0.262 
• R-Value Work: 0.237 

Literature

The Structure of the Arabidopsis Thaliana SOS3: Molecular Mechanism of Sensing Calcium for Salt Stress Response

Sanchez-Barrena, M.J., Martinez-Ripoll, M., Zhu, J.K., Albert, A.

(2005) J.Mol.Biol. 345: 1253

• PubMed: 15644219 
• DOI: 10.1016/j.jmb.2004.11.025
• Primary Citation of Related Structures:  
  1V1G


• PubMed Abstract: 
  

The Arabidopsis thaliana SOS3 gene encodes a calcium sensor that is required for plant salt tolerance. The SOS3 protein binds to and activates the self-inhibited SOS2 protein kinase, which mediates the expression and activities of various transporters important for ion homeostasis under salt stress. SOS3 belongs to a unique family of calcium-binding proteins that contain two pairs of EF hand motifs with four putative metal-binding sites. We report the crystal structure of a dimeric SOS3 protein in complex with calcium, and with calcium and manganese. Analytical ultracentrifugation experiments and circular dichroism measurements show that calcium binding is responsible for the dimerization of SOS3. This leads to a change in the global shape and surface properties of the protein that may be sufficient to transmit the Ca(2+) signal elicited during salt stress.

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Organizational Affiliation: 

Grupo de Cristalografía Macromolecular y Biología Estructural, Instituto de Química Física "Rocasolano", Consejo Superior de Investigaciones Científicas, Serrano 119, E-28006 Madrid, Spain.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
CALCINEURIN B-LIKE PROTEIN 4	A	222	Arabidopsis thaliana	Mutation(s): 0  Gene Names: CBL4 (SOS3)
Find proteins for O81223 (Arabidopsis thaliana) Go to UniProtKB:  O81223

Small Molecules

Ligands 4 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram & Interactions
MN	A	MANGANESE (II) ION Mn WAEMQWOKJMHJLA-UHFFFAOYSA-N
IOD	A	IODIDE ION I XMBWDFGMSWQBCA-UHFFFAOYSA-M
CA	A	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N
MPD	A	(4S)-2-METHYL-2,4-PENTANEDIOL C6 H14 O2 SVTBMSDMJJWYQN-YFKPBYRVSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3 Å
• R-Value Free: 0.262 
• R-Value Work: 0.237 
• Space Group: I 4₁

Unit Cell:

Length (Å)	Angle (°)
a = 91.900	α = 90.00
b = 91.900	β = 90.00
c = 85.600	γ = 90.00

Software Package:

Software Name	Purpose
SCALA	data scaling
CCP4	phasing
REFMAC	refinement
MOSFLM	data reduction

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2004-04-15 
• Released Date: 2005-01-19 
• Deposition Author(s): Sanchez-Barrena, M.J., Martinez-Ripoll, M., Zhu, J.K., Albert, A.

Revision History 

• Version 1.0: 2005-01-19
  Type: Initial release
• Version 1.1: 2011-05-08
  Type: Version format compliance
• Version 1.2: 2011-07-13
  Type: Version format compliance
• Version 1.3: 2019-10-16
  Type: Data collection, Experimental preparation, Other