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Symmetry Reduction in a Hyperpolarization-Activated Homotetrameric Ion Channel.

ABSTRACT: Plants obtain nutrients from the soil via transmembrane transporters and channels in their root hairs, from which ions radially transport in toward the xylem for distribution across the plant body. We determined structures of the hyperpolarization-activated channel AKT1 from Arabidopsis thaliana, which mediates K⁺ uptake from the soil into plant roots. These structures of AtAKT1 embedded in lipid nanodiscs show that the channel undergoes a reduction of C4 to C2 symmetry, possibly to regulate its electrical activation.

SUBMITTER: Dickinson MS

PROVIDER: S-EPMC9931035 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

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Symmetry Reduction in a Hyperpolarization-Activated Homotetrameric Ion Channel.

Dickinson Miles Sasha MS Pourmal Sergei S Gupta Meghna M Bi Maxine M Stroud Robert M RM

Biochemistry 20211229 20

Plants obtain nutrients from the soil via transmembrane transporters and channels in their root hairs, from which ions radially transport in toward the xylem for distribution across the plant body. We determined structures of the hyperpolarization-activated channel AKT1 from <i>Arabidopsis thaliana</i>, which mediates K<sup>+</sup> uptake from the soil into plant roots. These structures of AtAKT1 embedded in lipid nanodiscs show that the channel undergoes a reduction of C4 to C2 symmetry, possib ...[more]

PMID: 34964607

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