7EK3 image
Entry Detail
PDB ID:
7EK3
EMDB ID:
Title:
Cryo-EM structure of VCCN1 Y332A mutant in lipid nanodisc
Biological Source:
Source Organism:
Host Organism:
PDB Version:
Deposition Date:
2021-04-03
Release Date:
2022-04-06
Method Details:
Experimental Method:
Resolution:
2.70 Å
Aggregation State:
PARTICLE
Reconstruction Method:
SINGLE PARTICLE
Macromolecular Entities
Polymer Type:polypeptide(L)
Description:Bestrophin-like protein
Mutations:A207S, Y322A
Chain IDs:A
Chain Length:372
Number of Molecules:1
Biological Source:Malus domestica
Ligand Molecules
Primary Citation
Cryo-EM structures of thylakoid-located voltage-dependent chloride channel VCCN1.
Nat Commun 13 2505 2505 (2022)
PMID: 35523970 DOI: 10.1038/s41467-022-30292-w

Abstact

In the light reaction of plant photosynthesis, modulation of electron transport chain reactions is important to maintain the efficiency of photosynthesis under a broad range of light intensities. VCCN1 was recently identified as a voltage-gated chloride channel residing in the thylakoid membrane, where it plays a key role in photoreaction tuning to avoid the generation of reactive oxygen species (ROS). Here, we present the cryo-EM structures of Malus domestica VCCN1 (MdVCCN1) in nanodiscs and detergent at 2.7 Å and 3.0 Å resolutions, respectively, and the structure-based electrophysiological analyses. VCCN1 structurally resembles its animal homolog, bestrophin, a Ca2+-gated anion channel. However, unlike bestrophin channels, VCCN1 lacks the Ca2+-binding motif but instead contains an N-terminal charged helix that is anchored to the lipid membrane through an additional amphipathic helix. Electrophysiological experiments demonstrate that these structural elements are essential for the channel activity, thus revealing the distinct activation mechanism of VCCN1.

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Primary Citation of related structures