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Publication Abstract from PubMed

The beta-1,3-glucan recognition protein (betaGRP)/Gram-negative bacteria-binding protein 3 (GNBP3) is a crucial pattern-recognition receptor that specifically binds beta-1,3-glucan, a component of fungal cell walls. It evokes innate immunity against fungi through activation of the prophenoloxidase (proPO) cascade and Toll pathway in invertebrates. The betaGRP consists of an N-terminal beta-1,3-glucan-recognition domain and a C-terminal glucanase-like domain, with the former reported to be responsible for the proPO cascade activation. This report shows the solution structure of the N-terminal beta-1,3-glucan recognition domain of silkworm betaGRP. Although the N-terminal domain of betaGRP has a beta-sandwich fold, often seen in carbohydrate-binding modules, both NMR titration experiments and mutational analysis showed that betaGRP has a binding mechanism which is distinct from those observed in previously reported carbohydarate-binding domains. Our results suggest that betaGRP is a beta-1,3-glucan-recognition protein that specifically recognizes a triple-helical structure of beta-1,3-glucan.

Solution structure of the silkworm betaGRP/GNBP3 N-terminal domain reveals the mechanism for beta-1,3-glucan-specific recognition.,Takahasi K, Ochiai M, Horiuchi M, Kumeta H, Ogura K, Ashida M, Inagaki F Proc Natl Acad Sci U S A. 2009 Jul 14;106(28):11679-84. Epub 2009 Jun 26. PMID:19561300^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.