Thylakoid-located voltage-dependent chloride channel VCCN1
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ABSTRACT:
SUBMITTER: Tsukasa Kusakizako
PROVIDER: EMPIAR-11091 | biostudies-other |
REPOSITORIES: biostudies-other
Publications
Cryo-EM structures of thylakoid-located voltage-dependent chloride channel VCCN1.
Hagino Tatsuya T Kato Takafumi T Kasuya Go G Kobayashi Kan K Kusakizako Tsukasa T Hamamoto Shin S Sobajima Tomoaki T Fujiwara Yuichiro Y Yamashita Keitaro K Kawasaki Hisashi H Maturana Andrés D AD Nishizawa Tomohiro T Nureki Osamu O
Nature communications 20220506 1
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 de ...[more]
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Project description: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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