3UJK

Crystal structure of protein phosphatase ABI2

• PDB DOI: https://doi.org/10.2210/pdb3UJK/pdb

• Classification: HYDROLASE
• Organism(s): Arabidopsis thaliana
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2011-11-07 Released: 2012-02-15 
• Deposition Author(s): Zhou, X.E., Soon, F.-F., Ng, L.-M., Kovach, A., Tan, M.H.E., Suino-Powell, K.M., He, Y., Xu, Y., Brunzelle, J.S., Li, J., Melcher, K., Xu, H.E.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 0.220 
• R-Value Work: 0.195 
• R-Value Observed: 0.197 

Literature

Molecular mimicry regulates ABA signaling by SnRK2 kinases and PP2C phosphatases.

Soon, F.F., Ng, L.M., Zhou, X.E., West, G.M., Kovach, A., Tan, M.H., Suino-Powell, K.M., He, Y., Xu, Y., Chalmers, M.J., Brunzelle, J.S., Zhang, H., Yang, H., Jiang, H., Li, J., Yong, E.L., Cutler, S., Zhu, J.K., Griffin, P.R., Melcher, K., Xu, H.E.

(2012) Science 335: 85-88

• PubMed: 22116026 
• DOI: https://doi.org/10.1126/science.1215106
• Primary Citation of Related Structures:  
  3UJG, 3UJK, 3UJL


• PubMed Abstract: 
  

  Abscisic acid (ABA) is an essential hormone for plants to survive environmental stresses. At the center of the ABA signaling network is a subfamily of type 2C protein phosphatases (PP2Cs), which form exclusive interactions with ABA receptors and subfamily 2 Snfl-related kinase (SnRK2s). Here, we report a SnRK2-PP2C complex structure, which reveals marked similarity in PP2C recognition by SnRK2 and ABA receptors. In the complex, the kinase activation loop docks into the active site of PP2C, while the conserved ABA-sensing tryptophan of PP2C inserts into the kinase catalytic cleft, thus mimicking receptor-PP2C interactions. These structural results provide a simple mechanism that directly couples ABA binding to SnRK2 kinase activation and highlight a new paradigm of kinase-phosphatase regulation through mutual packing of their catalytic sites.

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Organizational Affiliation: 

Laboratory of Structural Sciences, Van Andel Research Institute, 333 Bostwick Avenue NE, Grand Rapids, MI 49503, USA.

Biological Assembly 1  

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

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

Macromolecule Content

• Total Structure Weight: 35.86 kDa 
• Atom Count: 2,477 
• Modelled Residue Count: 298 
• Deposited Residue Count: 324 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Protein phosphatase 2C 77	A	324	Arabidopsis thaliana	Mutation(s): 0  Gene Names: ABI2, At5g57050, MHM17.19 EC: 3.1.3.16
UniProt
Find proteins for O04719 (Arabidopsis thaliana) Explore O04719  Go to UniProtKB:  O04719

Small Molecules

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

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 0.220 
• R-Value Work: 0.195 
• R-Value Observed: 0.197 
• Space Group: P 3₂ 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 89.666	α = 90
b = 89.666	β = 90
c = 91.87	γ = 120

Software Package:

Software Name	Purpose
DENZO	data reduction
PHASER	phasing
REFMAC	refinement
PDB_EXTRACT	data extraction
HKL-2000	data collection
SCALEPACK	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2012-02-15 
Deposition Author(s): Zhou, X.E., Soon, F.-F., Ng, L.-M., Kovach, A., Tan, M.H.E., Suino-Powell, K.M., He, Y., Xu, Y., Brunzelle, J.S., Li, J., Melcher, K., Xu, H.E.

Revision History  

• Version 1.0: 2012-02-15
  Type: Initial release
  
• Version 1.1: 2024-02-28
  Changes: Data collection, Database references, Derived calculations