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Structural insights into the innate immune recognition specificities of L- and H-ficolins.

ABSTRACT: Innate immunity relies critically upon the ability of a few pattern recognition molecules to sense molecular markers on pathogens, but little is known about these interactions at the atomic level. Human L- and H-ficolins are soluble oligomeric defence proteins with lectin-like activity, assembled from collagen fibers prolonged by fibrinogen-like recognition domains. The X-ray structures of their trimeric recognition domains, alone and in complex with various ligands, have been solved to resolutions up to 1.95 and 1.7 A, respectively. Both domains have three-lobed structures with clefts separating the distal parts of the protomers. Ca(2+) ions are found at sites homologous to those described for tachylectin 5A (TL5A), an invertebrate lectin. Outer binding sites (S1) homologous to the GlcNAc-binding pocket of TL5A are present in the ficolins but show different structures and specificities. In L-ficolin, three additional binding sites (S2-S4) surround the cleft. Together, they define an unpredicted continuous recognition surface able to sense various acetylated and neutral carbohydrate markers in the context of extended polysaccharides such as 1,3-beta-D-glucan, as found on microbial or apoptotic surfaces.

SUBMITTER: Garlatti V

PROVIDER: S-EPMC1783469 | biostudies-literature | 2007 Jan

REPOSITORIES: biostudies-literature

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Structural insights into the innate immune recognition specificities of L- and H-ficolins.

Garlatti Virginie V Belloy Nicolas N Martin Lydie L Lacroix Monique M Matsushita Misao M Endo Yuichi Y Fujita Teizo T Fontecilla-Camps Juan Carlos JC Arlaud Gérard J GJ Thielens Nicole M NM Gaboriaud Christine C

The EMBO journal 20070111 2

Innate immunity relies critically upon the ability of a few pattern recognition molecules to sense molecular markers on pathogens, but little is known about these interactions at the atomic level. Human L- and H-ficolins are soluble oligomeric defence proteins with lectin-like activity, assembled from collagen fibers prolonged by fibrinogen-like recognition domains. The X-ray structures of their trimeric recognition domains, alone and in complex with various ligands, have been solved to resoluti ...[more]

PMID: 17215869

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Dataset Information

Structural insights into the innate immune recognition specificities of L- and H-ficolins.

Publications

Structural insights into the innate immune recognition specificities of L- and H-ficolins.

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