Biological Assembly 1  

 3D View: Structure

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 3-mer - A1B1C1 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 17.96 kDa 
• Atom Count: 1269 
• Residue Count: 163 
• Unique protein chains: 3

2MTP

The structure of Filamin repeat 21 bound to integrin

• DOI: 10.2210/pdb2MTP/pdb
• BMRB: 25176

• Classification: PROTEIN BINDING/Cell Adhesion
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): Yes 


• Deposited: 2014-08-28 Released: 2015-04-01 
• Deposition Author(s): Liu, J., Qin, J.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Calculated: 100 
• Conformers Submitted: 20 
• Selection Criteria: structures with the lowest energy 

Literature

Structural mechanism of integrin inactivation by filamin.

Liu, J., Das, M., Yang, J., Ithychanda, S.S., Yakubenko, V.P., Plow, E.F., Qin, J.

(2015) Nat Struct Mol Biol 22: 383-389

• PubMed: 25849143 
• DOI: 10.1038/nsmb.2999
• Primary Citation of Related Structures:  
  2MTP


• PubMed Abstract: 
  

Activation of heterodimeric (αβ) integrin is crucial for regulating cell adhesion. Binding of talin to the cytoplasmic face of integrin activates the receptor, but how integrin is maintained in a resting state to counterbalance its activation has remained obscure. Here, we report the structure of the cytoplasmic domain of human integrin αIIbβ3 bound to its inhibitor, the immunoglobin repeat 21 of filamin A (FLNa-Ig21). The structure reveals an unexpected ternary complex in which FLNa-Ig21 not only binds to the C terminus of the integrin β3 cytoplasmic tail (CT), as previously predicted, but also engages N-terminal helices of αIIb and β3 CTs to stabilize an inter-CT clasp that helps restrain the integrin in a resting state. Combined with functional data, the structure reveals a new mechanism of filamin-mediated retention of inactive integrin, suggesting a new framework for understanding regulation of integrin activation and adhesion.

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Organizational Affiliation: 

Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Filamin-A	A	95	Homo sapiens	Mutation(s): 0  Gene Names: FLNA, FLN, FLN1
Find proteins for P21333 (Homo sapiens) Explore P21333  Go to UniProtKB:  P21333
NIH Common Fund Data Resources
PHAROS:  P21333 GTEx:  ENSG00000196924

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Integrin alpha-IIb	B	21	Homo sapiens	Mutation(s): 0  Gene Names: ITGA2B, GP2B, ITGAB
Find proteins for P08514 (Homo sapiens) Explore P08514  Go to UniProtKB:  P08514
NIH Common Fund Data Resources
PHAROS:  P08514 GTEx:  ENSG00000005961

Entity ID: 3
Molecule	Chains	Sequence Length	Organism	Details	Image
Integrin beta-3	C	47	Homo sapiens	Mutation(s): 2  Gene Names: ITGB3, GP3A
Find proteins for P05106 (Homo sapiens) Explore P05106  Go to UniProtKB:  P05106
NIH Common Fund Data Resources
PHAROS:  P05106 GTEx:  ENSG00000259207

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Calculated: 100 
• Conformers Submitted: 20 
• Selection Criteria: structures with the lowest energy 
• OLDERADO: 2MTP Olderado

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2014-08-28 
• Released Date: 2015-04-01 
Deposition Author(s): Liu, J., Qin, J.

Revision History 

• Version 1.0: 2015-04-01
  Type: Initial release
  
• Version 1.1: 2015-07-01
  Changes: Database references