2RQE

Solution structure of the silkworm bGRP/GNBP3 N-terminal domain reveals the mechanism for b-1,3-glucan specific recognition

Summary for 2RQE

• Entry DOI: 10.2210/pdb2rqe/pdb
• Descriptor: Beta-1,3-glucan-binding protein (1 entity in total)
• Functional Keywords: protein, beta-1, 3-glucan, glycoprotein, immune response, innate immunity, secreted, sugar binding protein
• Biological source: Bombyx mori (silk moth)
• Cellular location: Secreted (By similarity): Q9NL89
• Total number of polymer chains: 1
• Total formula weight: 12094.57

Authors

Takahasi, K.,Ochiai, M.,Horiuchi, M.,Kumeta, H.,Ogura, K.,Ashida, M.,Inagaki, F. (deposition date: 2009-04-22, release date: 2009-06-23, Last modification date: 2024-05-29)

Primary citation

Takahasi, K.,Ochiai, M.,Horiuchi, M.,Kumeta, H.,Ogura, K.,Ashida, M.,Inagaki, F.
Solution structure of the silkworm betaGRP/GNBP3 N-terminal domain reveals the mechanism for beta-1,3-glucan-specific recognition.
Proc.Natl.Acad.Sci.USA, 106:11679-11684, 2009

PubMed Abstract: 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.

PubMed: 19561300
DOI: 10.1073/pnas.0901671106

Experimental method

SOLUTION NMR