7WNQ image
Deposition Date 2022-01-19
Release Date 2022-04-13
Last Version Date 2024-06-26
Entry Detail
PDB ID:
7WNQ
Title:
Cryo-EM structure of AtSLAC1 S59A mutant
Biological Source:
Source Organism:
Host Organism:
Method Details:
Experimental Method:
Resolution:
2.70 Å
Aggregation State:
PARTICLE
Reconstruction Method:
SINGLE PARTICLE
Macromolecular Entities
Polymer Type:polypeptide(L)
Molecule:Guard cell S-type anion channel SLAC1
Gene (Uniprot):SLAC1
Chain IDs:A, B, C
Chain Length:556
Number of Molecules:3
Biological Source:Arabidopsis thaliana
Ligand Molecules
Primary Citation
Structure of the Arabidopsis guard cell anion channel SLAC1 suggests activation mechanism by phosphorylation.
Nat Commun 13 2511 2511 (2022)
PMID: 35523967 DOI: 10.1038/s41467-022-30253-3

Abstact

Stomata play a critical role in the regulation of gas exchange and photosynthesis in plants. Stomatal closure participates in multiple stress responses, and is regulated by a complex network including abscisic acid (ABA) signaling and ion-flux-induced turgor changes. The slow-type anion channel SLAC1 has been identified to be a central controller of stomatal closure and phosphoactivated by several kinases. Here, we report the structure of SLAC1 in Arabidopsis thaliana (AtSLAC1) in an inactivated, closed state. The cytosolic amino (N)-terminus and carboxyl (C)-terminus of AtSLAC1 are partially resolved and form a plug-like structure which packs against the transmembrane domain (TMD). Breaking the interactions between the cytosolic plug and transmembrane domain triggers channel activation. An inhibition-release model is proposed for SLAC1 activation by phosphorylation that the cytosolic plug dissociates from the transmembrane domain upon phosphorylation, and induces conformational changes to open the pore. These findings facilitate our understanding of the regulation of SLAC1 activity and stomatal aperture in plants.

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Primary Citation of related structures