title: Brush border membrane aminopeptidase-N in the midgut of the gypsy moth serves as the receptor for the CryIA(c) delta-endotoxin of Bacillus thuringiensis.
abstract: Aminopeptidase-N (AP-N) was purified from gypsy moth (Lymantria dispar, L.) brush border membrane vesicles (BBMV) proteins by mono-Q chromatography and Superdex-75 gel filtration in the presence of the zwitterionic detergent, CHAPS, using FPLC. The purified AP-N, identified by its enzymatic activity, had an apparent size of 100 kDa, and was identified as the unique Bacillus thuringiensis insecticidal toxin, CryIA(c), binding protein. AP-N clearly displayed strong binding to CryIA(c), exhibiting little or no binding to CryIA(a) or CryIA(b), and showing no binding for the coleopteran-specific toxin, CryIIIA. Protein blots of the BBMV proteins probed with biotin-labeled and 125I-labeled insecticidal proteins revealed that CryIAc binds only to 120 kDa protein which is a slightly larger size in comparison to purified AP-N. Antibodies raised against the gypsy moth AP-N demonstrated that the purified AP-N and the 120 kDa CryIA(c) binding protein of total BBMV proteins are antigenically identical.
authors.affiliation: USDA Forest Service, Northeastern Forest Experiment Station, Delaware, OH 43015, USA.
authors.forename: A P
authors.initials: AP
authors.lastname: Valaitis
authors.forename: M K
authors.initials: MK
authors.lastname: Lee
authors.forename: F
authors.initials: F
authors.lastname: Rajamohan
authors.forename: D H
authors.initials: DH
authors.lastname: Dean
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001413:Bacillus thuringiensis / Q000378:metabolism*; D001426:Bacterial Proteins; D018826:CD13 Antigens / Q000302:isolation & purification / Q000378:metabolism*; D004064:Digestive System; D006801:Humans; D019476:Insect Proteins; D008871:Microvilli / Q000201:enzymology; D008969:Molecular Sequence Data; D009036:Moths / Q000201:enzymology*; D011956:Receptors, Cell Surface / Q000302:isolation & purification / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid
chemical_list: D001426:Bacterial Proteins; C095416:Cry toxin receptors; D019476:Insect Proteins; D011956:Receptors, Cell Surface; D018826:CD13 Antigens