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Open data
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Basic information
Entry | Database: EMDB / ID: EMD-32328 | ||||||||||||
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Title | Cryo-EM structure of GmALMT12/QUAC1 anion channel | ||||||||||||
![]() | Half map 2 for GmALMT12/QUAC1 | ||||||||||||
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Function / homology | malate transport / Aluminum-activated malate transporter / Aluminium activated malate transporter / plant-type vacuole membrane / monoatomic ion transmembrane transport / membrane => GO:0016020 / Uncharacterized protein![]() | ||||||||||||
Biological species | ![]() ![]() ![]() | ||||||||||||
Method | ![]() ![]() | ||||||||||||
![]() | Qin L / Tang LH / Xu JS / Zhang XH / Zhu Y / Sun F / Su M / Zhai YJ / Chen YH | ||||||||||||
Funding support | ![]()
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![]() | ![]() Title: Cryo-EM structure and electrophysiological characterization of ALMT from reveal a previously uncharacterized class of anion channels. Authors: Li Qin / Ling-Hui Tang / Jia-Shu Xu / Xian-Hui Zhang / Yun Zhu / Chun-Rui Zhang / Mei-Hua Wang / Xue-Lei Liu / Fei Li / Fei Sun / Min Su / Yujia Zhai / Yu-Hang Chen / ![]() ![]() Abstract: Aluminum-activated malate transporters (ALMTs) form an anion channel family that plays essential roles in diverse functions in plants. ALMT12, also named QUAC1 (quick anion channel 1), regulates ...Aluminum-activated malate transporters (ALMTs) form an anion channel family that plays essential roles in diverse functions in plants. ALMT12, also named QUAC1 (quick anion channel 1), regulates stomatal closure in response to environmental stimuli. However, the molecular basis of ALMT12/QUAC1 activity remains elusive. Here, we describe the cryo-EM structure of ALMT12/QUAC1 from at 3.5-Å resolution. ALMT12/QUAC1 is a symmetrical dimer, forming a single electropositive T-shaped pore across the membrane. The transmembrane and cytoplasmic domains are assembled into a twisted two-layer architecture, with their associated dimeric interfaces nearly perpendicular. ALMT12/QUAC1-mediated currents display rapid kinetics of activation/deactivation and a bell-shaped voltage dependency, reminiscent of the rapid (R)-type anion currents. Our structural and functional analyses reveal a domain-twisting mechanism for malate-mediated activation. Together, our study uncovers the molecular basis for a previously uncharacterized class of anion channels and provides insights into the gating and modulation of the ALMT12/QUAC1 anion channel. | ||||||||||||
History |
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Structure visualization
Movie |
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Structure viewer | EM map: ![]() ![]() ![]() |
Supplemental images |
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Downloads & links
-EMDB archive
Map data | ![]() | 21 MB | ![]() | |
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Header (meta data) | ![]() ![]() | 19.4 KB 19.4 KB | Display Display | ![]() |
Images | ![]() | 69.9 KB | ||
Others | ![]() ![]() ![]() | 40.3 MB 39.8 MB 39.8 MB | ||
Archive directory | ![]() ![]() | HTTPS FTP |
-Related structure data
Related structure data | ![]() 7w6kMC M: atomic model generated by this map C: citing same article ( |
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Similar structure data |
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Links
EMDB pages | ![]() ![]() |
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Map
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Annotation | Half map 2 for GmALMT12/QUAC1 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Voxel size | X=Y=Z: 1.04 Å | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Density |
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Symmetry | Space group: 1 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Details | EMDB XML:
CCP4 map header:
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-Supplemental data
-Additional map: Sharpen map for GmALMT12/QUAC1
File | emd_32328_additional_1.map | ||||||||||||
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Annotation | Sharpen map for GmALMT12/QUAC1 | ||||||||||||
Projections & Slices |
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Density Histograms |
-Half map: Reconstructed Density map for GmALMT12/QUAC1
File | emd_32328_half_map_1.map | ||||||||||||
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Annotation | Reconstructed Density map for GmALMT12/QUAC1 | ||||||||||||
Projections & Slices |
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Density Histograms |
-Half map: Half map 1 for GmALMT12/QUAC1
File | emd_32328_half_map_2.map | ||||||||||||
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Annotation | Half map 1 for GmALMT12/QUAC1 | ||||||||||||
Projections & Slices |
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Density Histograms |
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Sample components
-Entire : GmALMT12/QUAC1
Entire | Name: GmALMT12/QUAC1 |
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Components |
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-Supramolecule #1: GmALMT12/QUAC1
Supramolecule | Name: GmALMT12/QUAC1 / type: organelle_or_cellular_component / ID: 1 / Parent: 0 / Macromolecule list: all |
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Source (natural) | Organism: ![]() ![]() ![]() |
Recombinant expression | Organism: ![]() ![]() ![]() |
-Macromolecule #1: GmALMT12/QUAC1
Macromolecule | Name: GmALMT12/QUAC1 / type: protein_or_peptide / ID: 1 / Number of copies: 2 / Enantiomer: LEVO |
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Source (natural) | Organism: ![]() ![]() ![]() |
Molecular weight | Theoretical: 60.321969 KDa |
Recombinant expression | Organism: ![]() ![]() ![]() |
Sequence | String: MVPKVYAGQE MAMVENENCI MNGKWKKRVH VFGERVMRFP NKAWQTTWKV GREDPRRLIH AFKVGLSLTL ASLLYLLEPL FKGIGQSAI WAVMTVVVVL EFTAGATLCK GLNRGLGTLL AGLLAFLVGY IANASDRVSQ AIIIGAAVFF IGALATYMRF I PYIKKNYD ...String: MVPKVYAGQE MAMVENENCI MNGKWKKRVH VFGERVMRFP NKAWQTTWKV GREDPRRLIH AFKVGLSLTL ASLLYLLEPL FKGIGQSAI WAVMTVVVVL EFTAGATLCK GLNRGLGTLL AGLLAFLVGY IANASDRVSQ AIIIGAAVFF IGALATYMRF I PYIKKNYD YGLVIFLLTF NLITVSSYRL ENVLKIAHDR VYTIAIGCAV CLLMSLLVFP NWSGEDLHNS TVYKLEGLAK SI EACVNEY FYGEIEGSGY MKLSEDPIYK GYKAVLDSKS IDETLALHAS WEPRHSRYCH RFPWQQYVKV GAVLRQFGYT VVA LHGCLR TEIQTPRSVR AMFKDPCIRL AAEVSKVLIE LSNSIRNRRH CSPEILSDHL HEALQDLNTA IKSQPRLFLG PKHR HNQAT NMLKIAAAQV GQERHGKTSL SSVKTDSSAL LEWKTKRVSA EQTKESERKS LRPQLSKIAI TSLEFSEALP FAAFA SLLV ETVAKLDLVI EEVEELGRLA CFKEFIPGDE FVVTCQEPRV DVSQNHLPSH GVD |
-Experimental details
-Structure determination
Method | ![]() |
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Aggregation state | particle |
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Sample preparation
Concentration | 5 mg/mL |
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Buffer | pH: 8 |
Grid | Model: Quantifoil R1.2/1.3 / Material: GOLD / Mesh: 300 / Pretreatment - Type: GLOW DISCHARGE / Pretreatment - Atmosphere: OTHER |
Vitrification | Cryogen name: ETHANE / Chamber humidity: 100 % / Instrument: FEI VITROBOT MARK IV |
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Electron microscopy
Microscope | FEI TITAN KRIOS |
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Electron beam | Acceleration voltage: 300 kV / Electron source: ![]() |
Electron optics | Illumination mode: FLOOD BEAM / Imaging mode: BRIGHT FIELD![]() |
Image recording | Film or detector model: GATAN K2 SUMMIT (4k x 4k) / Detector mode: SUPER-RESOLUTION / Number real images: 6189 / Average exposure time: 8.0 sec. / Average electron dose: 60.0 e/Å2 |
Experimental equipment | ![]() Model: Titan Krios / Image courtesy: FEI Company |
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Image processing
Particle selection | Number selected: 2987283 |
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CTF correction | Software - Name: Gctf |
Initial angle assignment | Type: MAXIMUM LIKELIHOOD |
Final angle assignment | Type: MAXIMUM LIKELIHOOD / Software - Name: cryoSPARC (ver. 3.1) |
Final reconstruction | Applied symmetry - Point group: C2 (2 fold cyclic![]() |
-Atomic model buiding 1
Refinement | Space: REAL / Protocol: AB INITIO MODEL |
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Output model | ![]() PDB-7w6k: |