First Author | Yoon SI | Year | 2011 |
Journal | Nat Struct Mol Biol | Volume | 18 |
Issue | 9 | Pages | 1028-35 |
PubMed ID | 21857663 | Mgi Jnum | J:245260 |
Mgi Id | MGI:5914828 | Doi | 10.1038/nsmb.2106 |
Citation | Yoon SI, et al. (2011) An unusual dimeric structure and assembly for TLR4 regulator RP105-MD-1. Nat Struct Mol Biol 18(9):1028-35 |
abstractText | 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 A 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. |