+Open data
-Basic information
Entry | Database: EMDB / ID: EMD-23245 | |||||||||
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Title | Integrin AlphaIIbBeta3-PT25-2 Complex | |||||||||
Map data | Cryo-EM map of Human aIIBb3 integrin headpiece with PT25-2 antibody fragment bound | |||||||||
Sample |
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Function / homology | Function and homology information tube development / regulation of serotonin uptake / positive regulation of adenylate cyclase-inhibiting opioid receptor signaling pathway / alpha9-beta1 integrin-ADAM8 complex / regulation of trophoblast cell migration / integrin alphaIIb-beta3 complex / regulation of postsynaptic neurotransmitter receptor diffusion trapping / alphav-beta3 integrin-vitronectin complex / regulation of extracellular matrix organization / platelet alpha granule membrane ...tube development / regulation of serotonin uptake / positive regulation of adenylate cyclase-inhibiting opioid receptor signaling pathway / alpha9-beta1 integrin-ADAM8 complex / regulation of trophoblast cell migration / integrin alphaIIb-beta3 complex / regulation of postsynaptic neurotransmitter receptor diffusion trapping / alphav-beta3 integrin-vitronectin complex / regulation of extracellular matrix organization / platelet alpha granule membrane / positive regulation of glomerular mesangial cell proliferation / integrin alphav-beta3 complex / negative regulation of lipoprotein metabolic process / alphav-beta3 integrin-PKCalpha complex / fibrinogen binding / maintenance of postsynaptic specialization structure / alphav-beta3 integrin-HMGB1 complex / blood coagulation, fibrin clot formation / vascular endothelial growth factor receptor 2 binding / negative regulation of lipid transport / glycinergic synapse / negative regulation of low-density lipoprotein receptor activity / angiogenesis involved in wound healing / Elastic fibre formation / regulation of release of sequestered calcium ion into cytosol / mesodermal cell differentiation / cell-substrate junction assembly / alphav-beta3 integrin-IGF-1-IGF1R complex / platelet-derived growth factor receptor binding / filopodium membrane / extracellular matrix binding / positive regulation of fibroblast migration / regulation of postsynaptic neurotransmitter receptor internalization / positive regulation of vascular endothelial growth factor receptor signaling pathway / apolipoprotein A-I-mediated signaling pathway / regulation of bone resorption / apoptotic cell clearance / positive regulation of cell adhesion mediated by integrin / wound healing, spreading of epidermal cells / heterotypic cell-cell adhesion / integrin complex / Molecules associated with elastic fibres / positive regulation of leukocyte migration / cellular response to insulin-like growth factor stimulus / positive regulation of cell-matrix adhesion / smooth muscle cell migration / cell adhesion mediated by integrin / microvillus membrane / negative chemotaxis / Syndecan interactions / p130Cas linkage to MAPK signaling for integrins / cellular response to platelet-derived growth factor stimulus / activation of protein kinase activity / cell-substrate adhesion / protein disulfide isomerase activity / positive regulation of smooth muscle cell migration / positive regulation of osteoblast proliferation / TGF-beta receptor signaling activates SMADs / PECAM1 interactions / lamellipodium membrane / GRB2:SOS provides linkage to MAPK signaling for Integrins / platelet-derived growth factor receptor signaling pathway / fibronectin binding / negative regulation of macrophage derived foam cell differentiation / negative regulation of lipid storage / ECM proteoglycans / positive regulation of T cell migration / positive regulation of bone resorption / Integrin cell surface interactions / coreceptor activity / negative regulation of endothelial cell apoptotic process / positive regulation of substrate adhesion-dependent cell spreading / cell adhesion molecule binding / positive regulation of endothelial cell proliferation / embryo implantation / positive regulation of endothelial cell migration / Integrin signaling / substrate adhesion-dependent cell spreading / cell-matrix adhesion / response to activity / Signal transduction by L1 / integrin-mediated signaling pathway / regulation of actin cytoskeleton organization / protein kinase C binding / positive regulation of smooth muscle cell proliferation / wound healing / Signaling by high-kinase activity BRAF mutants / RUNX1 regulates genes involved in megakaryocyte differentiation and platelet function / MAP2K and MAPK activation / platelet activation / cell-cell adhesion / platelet aggregation / VEGFA-VEGFR2 Pathway / ruffle membrane / cellular response to mechanical stimulus / positive regulation of angiogenesis / Signaling by RAF1 mutants / Signaling by moderate kinase activity BRAF mutants / Paradoxical activation of RAF signaling by kinase inactive BRAF / Signaling downstream of RAS mutants Similarity search - Function | |||||||||
Biological species | Mus musculus (house mouse) / Homo sapiens (human) | |||||||||
Method | single particle reconstruction / cryo EM / Resolution: 3.3 Å | |||||||||
Authors | Bush MW / Walz T / Coller B / Filizola M / Spasic A / Nesic D / Li J | |||||||||
Funding support | United States, 1 items
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Citation | Journal: Blood Adv / Year: 2021 Title: Electron microscopy shows that binding of monoclonal antibody PT25-2 primes integrin αIIbβ3 for ligand binding. Authors: Dragana Nešić / Martin Bush / Aleksandar Spasic / Jihong Li / Tetsuji Kamata / Makoto Handa / Marta Filizola / Thomas Walz / Barry S Coller / Abstract: The murine monoclonal antibody (mAb) PT25-2 induces αIIbβ3 to bind ligand and initiate platelet aggregation. The underlying mechanism is unclear, because previous mutagenesis studies suggested that ...The murine monoclonal antibody (mAb) PT25-2 induces αIIbβ3 to bind ligand and initiate platelet aggregation. The underlying mechanism is unclear, because previous mutagenesis studies suggested that PT25-2 binds to the αIIb β propeller, a site distant from the Arg-Gly-Asp-binding pocket. To elucidate the mechanism, we studied the αIIbβ3-PT25-2 Fab complex by negative-stain and cryo-electron microscopy (EM). We found that PT25-2 binding results in αIIbβ3 partially exposing multiple ligand-induced binding site epitopes and adopting extended conformations without swing-out of the β3 hybrid domain. The cryo-EM structure showed PT25-2 binding to the αIIb residues identified by mutagenesis but also to 2 additional regions. Overlay of the cryo-EM structure with the bent αIIbβ3 crystal structure showed that binding of PT25-2 creates clashes with the αIIb calf-1/calf-2 domains, suggesting that PT25-2 selectively binds to partially or fully extended receptor conformations and prevents a return to its bent conformation. Kinetic studies of the binding of PT25-2 compared with mAbs 10E5 and 7E3 support this hypothesis. We conclude that PT25-2 induces αIIbβ3 ligand binding by binding to extended conformations and by preventing the interactions between the αIIb and β3 leg domains and subsequently the βI and β3 leg domains required for the bent-closed conformation. | |||||||||
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_23245.map.gz | 117.2 MB | EMDB map data format | |
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Header (meta data) | emd-23245-v30.xml emd-23245.xml | 17.8 KB 17.8 KB | Display Display | EMDB header |
Images | emd_23245.png | 173.2 KB | ||
Archive directory | http://ftp.pdbj.org/pub/emdb/structures/EMD-23245 ftp://ftp.pdbj.org/pub/emdb/structures/EMD-23245 | HTTPS FTP |
-Related structure data
Related structure data | 7la4MC 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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Related items in Molecule of the Month |
-Map
File | Download / File: emd_23245.map.gz / Format: CCP4 / Size: 125 MB / Type: IMAGE STORED AS FLOATING POINT NUMBER (4 BYTES) | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Annotation | Cryo-EM map of Human aIIBb3 integrin headpiece with PT25-2 antibody fragment bound | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Voxel size | X=Y=Z: 1 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 : Human aIIBb3 integrin headpiece with PT25-2 antibody fragment bound
+Supramolecule #1: Human aIIBb3 integrin headpiece with PT25-2 antibody fragment bound
+Supramolecule #2: PT25-2 heavy and light chains
+Supramolecule #3: aIIBb3 integrin headpiece
+Macromolecule #1: PT25-2 heavy chain
+Macromolecule #2: PT25-2 light chain
+Macromolecule #3: Integrin alpha-IIb
+Macromolecule #4: Integrin beta-3
+Macromolecule #8: CALCIUM ION
+Macromolecule #9: 2-acetamido-2-deoxy-beta-D-glucopyranose
+Macromolecule #10: MAGNESIUM ION
+Macromolecule #11: water
-Experimental details
-Structure determination
Method | cryo EM |
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Processing | single particle reconstruction |
Aggregation state | particle |
-Sample preparation
Buffer | pH: 7.4 |
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Grid | Model: Quantifoil R1.2/1.3 / Material: COPPER / Support film - Material: CARBON / Support film - topology: HOLEY / Pretreatment - Type: GLOW DISCHARGE / Pretreatment - Atmosphere: AIR |
Vitrification | Cryogen name: ETHANE / Chamber humidity: 100 % / Chamber temperature: 277 K / Instrument: FEI VITROBOT MARK IV |
-Electron microscopy
Microscope | FEI TITAN KRIOS |
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Image recording | Film or detector model: GATAN K2 SUMMIT (4k x 4k) / Detector mode: SUPER-RESOLUTION / Average electron dose: 80.0 e/Å2 |
Electron beam | Acceleration voltage: 300 kV / Electron source: FIELD EMISSION GUN |
Electron optics | Illumination mode: FLOOD BEAM / Imaging mode: BRIGHT FIELD |
Sample stage | Specimen holder model: FEI TITAN KRIOS AUTOGRID HOLDER / Cooling holder cryogen: NITROGEN |
Experimental equipment | Model: Titan Krios / Image courtesy: FEI Company |
-Image processing
Final reconstruction | Resolution.type: BY AUTHOR / Resolution: 3.3 Å / Resolution method: FSC 0.143 CUT-OFF / Number images used: 166124 |
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Initial angle assignment | Type: MAXIMUM LIKELIHOOD |
Final angle assignment | Type: MAXIMUM LIKELIHOOD |