1FCG

ECTODOMAIN OF HUMAN FC GAMMA RECEPTOR, FCGRIIA

• PDB DOI: https://doi.org/10.2210/pdb1FCG/pdb

• Classification: IMMUNE SYSTEM, MEMBRANE PROTEIN
• Organism(s): Homo sapiens
• Expression System: Spodoptera frugiperda
• Mutation(s): Yes 


• Deposited: 1999-04-07 Released: 2000-04-12 
• Deposition Author(s): Maxwell, K.F., Powell, M.S., Garrett, T.P., Hogarth, P.M.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Free: 0.242 
• R-Value Work: 0.197 
• R-Value Observed: 0.218 

Literature

Crystal structure of the human leukocyte Fc receptor, Fc gammaRIIa.

Maxwell, K.F., Powell, M.S., Hulett, M.D., Barton, P.A., McKenzie, I.F., Garrett, T.P., Hogarth, P.M.

(1999) Nat Struct Biol 6: 437-442

• PubMed: 10331870 
• DOI: https://doi.org/10.1038/8241
• Primary Citation of Related Structures:  
  1FCG


• PubMed Abstract: 
  

  Fc gamma receptors bind IgG to initiate cellular responses against pathogens and soluble antigens. We have determined the three-dimensional structure of the extracellular portion of human Fc gammaRIIa to 2.0 A resolution providing a structural basis for the unique functions of the leukocyte FcR family. The receptor is composed of two immunoglobulin domains and arranged to expose the ligand-binding site at one end of domain 2. Using alanine mutants we find that the binding sites for IgG1 and 2 are similar but the relative importance of specific regions on the receptor varies. In crystals, Fc gammaRIIa molecules associate to resemble V(L)V(H) dimers, suggesting that two Fc gammaRIIa molecules could cooperate to bind IgG in an asymmetric manner.

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Organizational Affiliation: 

Biomolecular Research Institute, Parkville, Victoria, Australia.

Biological Assembly 1  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 19.56 kDa 
• Atom Count: 1,483 
• Modelled Residue Count: 171 
• Deposited Residue Count: 174 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PROTEIN (FC RECEPTOR FC(GAMMA)RIIA)	A	174	Homo sapiens	Mutation(s): 2
UniProt & NIH Common Fund Data Resources
Find proteins for P12318 (Homo sapiens) Explore P12318  Go to UniProtKB:  P12318
PHAROS:  P12318 GTEx:  ENSG00000143226

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Free: 0.242 
• R-Value Work: 0.197 
• R-Value Observed: 0.218 
• Space Group: P 2₁ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 79.221	α = 90
b = 100.866	β = 90
c = 28.172	γ = 90

Software Package:

Software Name	Purpose
DENZO	data reduction
SCALEPACK	data scaling
SHARP	phasing
DM	model building
REFMAC	refinement
DM	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2000-04-12 
Deposition Author(s): Maxwell, K.F., Powell, M.S., Garrett, T.P., Hogarth, P.M.

Revision History  

• Version 1.0: 2000-04-12
  Type: Initial release
  
• Version 1.1: 2008-04-26
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2018-04-04
  Changes: Data collection
• Version 1.4: 2018-04-11
  Changes: Data collection
• Version 1.5: 2023-12-27
  Changes: Data collection, Database references
• Version 1.6: 2024-10-16
  Changes: Structure summary