An ADAM metalloprotease is a Cry3Aa Bacillus thuringiensis toxin receptor

• Published in: Biochemical and biophysical research communications 2007-10, Vol.362 (2), p.437-442
• Main Authors: Ochoa-Campuzano, Camila, Real, M. Dolores, Martínez-Ramírez, Amparo C., Bravo, Alejandra, Rausell, Carolina
• Format: Article
• Language: English
• Subjects: ADAM; ADAM Proteins - chemistry; ADAM Proteins - metabolism; Amino Acid Sequence; Animals; Bacillus thuringiensis; Bacterial Proteins - chemistry; Bacterial Proteins - genetics; Bacterial Proteins - metabolism; Bacterial Toxins - chemistry; Bacterial Toxins - genetics; Bacterial Toxins - metabolism; Binding Sites - genetics; Carrier Proteins - chemistry; Carrier Proteins - metabolism; Cell Membrane - enzymology; Cell Membrane - metabolism; Coleoptera; Colorado potato beetle; Cry3A; Electrophoresis, Gel, Two-Dimensional; Endotoxins - chemistry; Endotoxins - genetics; Endotoxins - metabolism; Fluorescent Dyes - chemistry; Fluorescent Dyes - metabolism; Hemolysin Proteins - chemistry; Hemolysin Proteins - genetics; Hemolysin Proteins - metabolism; Insect Proteins - chemistry; Insect Proteins - metabolism; Insecticidal toxin; Metalloprotease; Microvilli - enzymology; Microvilli - metabolism; Models, Molecular; Molecular Sequence Data; Oligopeptides - chemistry; Oligopeptides - metabolism; Protein Binding; Protein Structure, Tertiary; Receptor; Sequence Analysis, Protein; Sequence Homology, Amino Acid; Solanum tuberosum; Substrate Specificity
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2007.07.197

Bacillus thuringiensis insecticidal proteins toxic action relies on the interaction with receptor molecules on insect midgut target cells. Here, we describe an ADAM metalloprotease as a novel type of B. thuringiensis toxin receptor on the basis of the following data: (i) by ligand blot and N-terminal analysis, we detected a Colorado potato beetle Cry3Aa toxin binding molecule that shares homology with an ADAM10 metalloprotease; (ii) Colorado potato beetle brush border membrane vesicles display ADAM activity since it cleaves an ADAM fluorogenic substrate; (iii) Cry3Aa acts as a competitor of the cleavage of the ADAM fluorogenic substrate; (iv) Cry3Aa sequence contains the recognition motif R 345FQPGYYGND 354 present in ADAM10 substrates. Accordingly, a peptide representative of the recognition motif localized within loop 1 of Cry3Aa domain II (Ac-F 341HTRFQPGYYGNDSFN 358-NH 2) effectively prevented Cry3Aa proteolytic processing and nearly abolished pore formation, evidencing the functional significance of the Cry3Aa–ADAM interaction in relation to this toxin mode of action.