+Open data
-Basic information
Entry | Database: EMDB / ID: EMD-23300 | |||||||||
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Title | Structure of lysosomal membrane protein | |||||||||
Map data | lysosomal membrane protein | |||||||||
Sample |
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Keywords | Channel / MEMBRANE PROTEIN | |||||||||
Function / homology | Function and homology information lysosomal lumen pH elevation / phagosome-lysosome fusion / regulation of lysosomal lumen pH / potassium ion leak channel activity / proton channel activity / arachidonate binding / potassium channel activity / potassium ion transmembrane transport / proton transmembrane transport / neuron cellular homeostasis ...lysosomal lumen pH elevation / phagosome-lysosome fusion / regulation of lysosomal lumen pH / potassium ion leak channel activity / proton channel activity / arachidonate binding / potassium channel activity / potassium ion transmembrane transport / proton transmembrane transport / neuron cellular homeostasis / lysosome / endosome membrane / endosome / lysosomal membrane Similarity search - Function | |||||||||
Biological species | Homo sapiens (human) | |||||||||
Method | single particle reconstruction / cryo EM / Resolution: 3.5 Å | |||||||||
Authors | Shen C / Fu TM | |||||||||
Citation | Journal: Sci Adv / Year: 2022 Title: pH regulates potassium conductance and drives a constitutive proton current in human TMEM175. Authors: Wang Zheng / Chen Shen / Longfei Wang / Shaun Rawson / Wen Jun Xie / Carl Nist-Lund / Jason Wu / Zhangfei Shen / Shiyu Xia / Jeffrey R Holt / Hao Wu / Tian-Min Fu / Abstract: Human TMEM175, a noncanonical potassium (K) channel in endolysosomes, contributes to their pH stability and is implicated in the pathogenesis of Parkinson's disease (PD). Structurally, the TMEM175 ...Human TMEM175, a noncanonical potassium (K) channel in endolysosomes, contributes to their pH stability and is implicated in the pathogenesis of Parkinson's disease (PD). Structurally, the TMEM175 family exhibits an architecture distinct from canonical potassium channels, as it lacks the typical TVGYG selectivity filter. Here, we show that human TMEM175 not only exhibits pH-dependent structural changes that reduce K permeation at acidic pH but also displays proton permeation. TMEM175 constitutively conducts K at pH 7.4 but displays reduced K permeation at lower pH. In contrast, proton current through TMEM175 increases with decreasing pH because of the increased proton gradient. Molecular dynamics simulation, structure-based mutagenesis, and electrophysiological analysis suggest that K ions and protons share the same permeation pathway. The M393T variant of human TMEM175 associated with PD shows reduced function in both K and proton permeation. Together, our structural and electrophysiological analysis reveals a mechanism of TMEM175 regulation by pH. | |||||||||
History |
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-Structure visualization
Movie |
Movie viewer |
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Structure viewer | EM map: SurfViewMolmilJmol/JSmol |
Supplemental images |
-Downloads & links
-EMDB archive
Map data | emd_23300.map.gz | 110.3 MB | EMDB map data format | |
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Header (meta data) | emd-23300-v30.xml emd-23300.xml | 9.1 KB 9.1 KB | Display Display | EMDB header |
Images | emd_23300.png | 46.6 KB | ||
Archive directory | http://ftp.pdbj.org/pub/emdb/structures/EMD-23300 ftp://ftp.pdbj.org/pub/emdb/structures/EMD-23300 | HTTPS FTP |
-Validation report
Summary document | emd_23300_validation.pdf.gz | 339.6 KB | Display | EMDB validaton report |
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Full document | emd_23300_full_validation.pdf.gz | 339.1 KB | Display | |
Data in XML | emd_23300_validation.xml.gz | 6.5 KB | Display | |
Data in CIF | emd_23300_validation.cif.gz | 7.5 KB | Display | |
Arichive directory | https://ftp.pdbj.org/pub/emdb/validation_reports/EMD-23300 ftp://ftp.pdbj.org/pub/emdb/validation_reports/EMD-23300 | HTTPS FTP |
-Related structure data
Related structure data | 7lf6MC M: atomic model generated by this map C: citing same article (ref.) |
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Similar structure data |
-Links
EMDB pages | EMDB (EBI/PDBe) / EMDataResource |
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-Map
File | Download / File: emd_23300.map.gz / Format: CCP4 / Size: 125 MB / Type: IMAGE STORED AS FLOATING POINT NUMBER (4 BYTES) | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Annotation | lysosomal membrane protein | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Projections & slices | Image control
Images are generated by Spider. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Voxel size | X=Y=Z: 0.825 Å | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Density |
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Symmetry | Space group: 1 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Details | EMDB XML:
CCP4 map header:
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-Supplemental data
-Sample components
-Entire : Dimer of a membrane protein
Entire | Name: Dimer of a membrane protein |
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Components |
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-Supramolecule #1: Dimer of a membrane protein
Supramolecule | Name: Dimer of a membrane protein / type: complex / ID: 1 / Parent: 0 / Macromolecule list: all |
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Source (natural) | Organism: Homo sapiens (human) |
-Macromolecule #1: Endosomal/lysosomal potassium channel TMEM175
Macromolecule | Name: Endosomal/lysosomal potassium channel TMEM175 / type: protein_or_peptide / ID: 1 / Number of copies: 2 / Enantiomer: LEVO |
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Source (natural) | Organism: Homo sapiens (human) |
Molecular weight | Theoretical: 55.667219 KDa |
Recombinant expression | Organism: Homo sapiens (human) |
Sequence | String: MSQPRTPEQA LDTPGDCPPG RRDEDAGEGI QCSQRMLSFS DALLSIIATV MILPVTHTEI SPEQQFDRSV QRLLATRIAV YLMTFLIVT VAWAAHTRLF QVVGKTDDTL ALLNLACMMT ITFLPYTFSL MVTFPDVPLG IFLFCVCVIA IGVVQALIVG Y AFHFPHLL ...String: MSQPRTPEQA LDTPGDCPPG RRDEDAGEGI QCSQRMLSFS DALLSIIATV MILPVTHTEI SPEQQFDRSV QRLLATRIAV YLMTFLIVT VAWAAHTRLF QVVGKTDDTL ALLNLACMMT ITFLPYTFSL MVTFPDVPLG IFLFCVCVIA IGVVQALIVG Y AFHFPHLL SPQIQRSAHR ALYRRHVLGI VLQGPALCFA AAIFSLFFVP LSYLLMVTVI LLPYVSKVTG WCRDRLLGHR EP SAHPVEV FSFDLHEPLS KERVEAFSDG VYAIVATLLI LDICEDNVPD PKDVKERFSG SLVAALSATG PRFLAYFGSF ATV GLLWFA HHSLFLHVRK ATRAMGLLNT LSLAFVGGLP LAYQQTSAFA RQPRDELERV RVSCTIIFLA SIFQLAMWTT ALLH QAETL QPSVWFGGRE HVLMFAKLAL YPCASLLAFA STCLLSRFSV GIFHLMQIAV PCAFLLLRLL VGLALATLRV LRGLA RPEH PPPAPTGQDD PQSQLLPAPC UniProtKB: Endosomal/lysosomal proton channel TMEM175 |
-Experimental details
-Structure determination
Method | cryo EM |
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Processing | single particle reconstruction |
Aggregation state | particle |
-Sample preparation
Buffer | pH: 5.5 |
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Vitrification | Cryogen name: ETHANE |
-Electron microscopy
Microscope | FEI TITAN KRIOS |
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Image recording | Film or detector model: GATAN K3 (6k x 4k) / Average electron dose: 66.5 e/Å2 |
Electron beam | Acceleration voltage: 300 kV / Electron source: FIELD EMISSION GUN |
Electron optics | Illumination mode: FLOOD BEAM / Imaging mode: BRIGHT FIELD |
Experimental equipment | Model: Titan Krios / Image courtesy: FEI Company |
-Image processing
Startup model | Type of model: OTHER |
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Final reconstruction | Resolution.type: BY AUTHOR / Resolution: 3.5 Å / Resolution method: FSC 0.143 CUT-OFF / Number images used: 117539 |
Initial angle assignment | Type: PROJECTION MATCHING |
Final angle assignment | Type: ANGULAR RECONSTITUTION |