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1i1a
From Proteopedia
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| , resolution 2.80Å | |||||||
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| Ligands: | , , , , , , | ||||||
| Related: | 3fru, 1FC1, 1i1c
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
CRYSTAL STRUCTURE OF THE NEONATAL FC RECEPTOR COMPLEXED WITH A HETERODIMERIC FC
Overview
The neonatal Fc receptor (FcRn) transports immunoglobulin G (IgG) across epithelia, binding IgG in acidic vesicles (pH < or = 6.5) and releasing IgG in the blood at pH 7.4. Well-ordered FcRn/Fc crystals are prevented by the formation of "oligomeric ribbons" of FcRn dimers bridged by Fc homodimers, thus we crystallized a 1:1 complex between rat FcRn and a heterodimeric Fc containing only one FcRn binding site. The 2.8 A complex structure demonstrates that FcRn uses its alpha2 and beta2-microglobulin domains and carbohydrate to interact with the Fc C(gamma)2-C(gamma)3 interface. The structure reveals conformational changes in Fc and three titratable salt bridges that confer pH-dependent binding, and can be used to guide rational design of therapeutic IgGs with longer serum half-lives.
About this Structure
1I1A is a Protein complex structure of sequences from Rattus norvegicus. Full crystallographic information is available from OCA.
Reference
Crystal structure at 2.8 A of an FcRn/heterodimeric Fc complex: mechanism of pH-dependent binding., Martin WL, West AP Jr, Gan L, Bjorkman PJ, Mol Cell. 2001 Apr;7(4):867-77. PMID:11336709
Page seeded by OCA on Sun Mar 30 21:13:14 2008
