3UC3

The crystal structure of Snf1-related kinase 2.3


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.230 
  • R-Value Work: 0.212 
  • R-Value Observed: 0.214 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Structural basis for basal activity and autoactivation of abscisic acid (ABA) signaling SnRK2 kinases.

Ng, L.M.Soon, F.F.Zhou, X.E.West, G.M.Kovach, A.Suino-Powell, K.M.Chalmers, M.J.Li, J.Yong, E.L.Zhu, J.K.Griffin, P.R.Melcher, K.Xu, H.E.

(2011) Proc Natl Acad Sci U S A 108: 21259-21264

  • DOI: 10.1073/pnas.1118651109
  • Primary Citation of Related Structures:  
    3UC3, 3UC4

  • PubMed Abstract: 
  • Abscisic acid (ABA) is an essential hormone that controls plant growth, development, and responses to abiotic stresses. Central for ABA signaling is the ABA-mediated autoactivation of three monomeric Snf1-related kinases (SnRK2.2, -2.3, and -2.6). In the absence of ABA, SnRK2s are kept in an inactive state by forming physical complexes with type 2C protein phosphatases (PP2Cs) ...

    Abscisic acid (ABA) is an essential hormone that controls plant growth, development, and responses to abiotic stresses. Central for ABA signaling is the ABA-mediated autoactivation of three monomeric Snf1-related kinases (SnRK2.2, -2.3, and -2.6). In the absence of ABA, SnRK2s are kept in an inactive state by forming physical complexes with type 2C protein phosphatases (PP2Cs). Upon relief of this inhibition, SnRK2 kinases can autoactivate through unknown mechanisms. Here, we report the crystal structures of full-length Arabidopsis thaliana SnRK2.3 and SnRK2.6 at 1.9- and 2.3-Å resolution, respectively. The structures, in combination with biochemical studies, reveal a two-step mechanism of intramolecular kinase activation that resembles the intermolecular activation of cyclin-dependent kinases. First, release of inhibition by PP2C allows the SnRK2s to become partially active because of an intramolecular stabilization of the catalytic domain by a conserved helix in the kinase regulatory domain. This stabilization enables SnRK2s to gain full activity by activation loop autophosphorylation. Autophosphorylation is more efficient in SnRK2.6, which has higher stability than SnRK2.3 and has well-structured activation loop phosphate acceptor sites that are positioned next to the catalytic site. Together, these data provide a structural framework that links ABA-mediated release of PP2C inhibition to activation of SnRK2 kinases.


    Organizational Affiliation

    Laboratory of Structural Sciences, Van Andel Research Institute, Grand Rapids, MI 49503, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Serine/threonine-protein kinase SRK2IA361Arabidopsis thalianaMutation(s): 2 
Gene Names: SRK2I41KOSKL2SNRK2.3At5g66880MUD21.14
EC: 2.7.11.1
UniProt
Find proteins for Q39193 (Arabidopsis thaliana)
Explore Q39193 
Go to UniProtKB:  Q39193
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ39193
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CO
Query on CO

Download Ideal Coordinates CCD File 
B [auth A],
C [auth A],
D [auth A]
COBALT (II) ION
Co
XLJKHNWPARRRJB-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.230 
  • R-Value Work: 0.212 
  • R-Value Observed: 0.214 
  • Space Group: P 31 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 75.411α = 90
b = 75.411β = 90
c = 116.434γ = 120
Software Package:
Software NamePurpose
DENZOdata reduction
PHASERphasing
REFMACrefinement
PDB_EXTRACTdata extraction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report




Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2011-12-14
    Type: Initial release
  • Version 1.1: 2012-01-18
    Changes: Database references