3RG1

Crystal structure of the RP105/MD-1 complex

Summary for 3RG1

• Entry DOI: 10.2210/pdb3rg1/pdb
• Descriptor: CD180 molecule, LY86 protein, beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, ... (6 entities in total)
• Functional Keywords: leucine-rich repeat domain, beta-cup-like structure, immune regulation, immune system
• Biological source: Bos taurus (bovine); More
• Total number of polymer chains: 16
• Total formula weight: 701783.71

Authors

Yoon, S.I.,Hong, M.,Wilson, I.A. (deposition date: 2011-04-07, release date: 2011-08-31, Last modification date: 2024-11-20)

Primary citation

Yoon, S.I.,Hong, M.,Wilson, I.A.
An unusual dimeric structure and assembly for TLR4 regulator RP105-MD-1.
Nat.Struct.Mol.Biol., 18:1028-1035, 2011

PubMed Abstract: RP105-MD-1 modulates the TLR4-MD-2-mediated, innate immune response against bacterial lipopolysaccharide (LPS). The crystal structure of the bovine 1:1 RP105-MD-1 complex bound to a putative endogenous lipid at 2.9 Å resolution shares a similar overall architecture to its homolog TLR4-MD-2 but assembles into an unusual 2:2 homodimer that differs from any other known TLR-ligand assembly. The homodimer is assembled in a head-to-head orientation that juxtaposes the N-terminal leucine-rich repeats (LRRs) of the two RP105 chains, rather than the usual tail-to-tail configuration of C-terminal LRRs in ligand-activated TLR dimers, such as TLR1-TRL2, TLR2-TLR6, TLR3-TLR3 and TLR4-TLR4. Another unusual interaction is mediated by an RP105-specific asparagine-linked glycan, which wedges MD-1 into the co-receptor binding concavity on RP105. This unique mode of assembly represents a new paradigm for TLR complexes and suggests a molecular mechanism for regulating LPS responses.

PubMed: 21857663
DOI: 10.1038/nsmb.2106

Experimental method

X-RAY DIFFRACTION (2.91 Å)