Homologous competition binding assays with BBMV from C. puncticollis. Biotinylated chymotrypsin-activated Cry3Bb (A), biotinylated chymotrypsin-activated Cry3Ca (B), biotinylated trypsin-activated Cry7Aa (C), or biotinylated chymotrypsin-activated Cry7Aa (D) was incubated with (50× to 200×) or without (−) an excess of unlabeled activated protein. Input indicates biotinylated Cry proteins. The double and single arrowheads indicate the 70-kDa and 65-kDa fragments, respectively, obtained after trypsin or chymotrypsin processing of the Cry7Aa protein.