Cloning and complete sequence characterization of two gypsy moth aminopeptidase-N cDNAs, including the receptor for Bacillus thuringiensis Cry1Ac toxin

The complete cDNAs corresponding to two distinct gypsy moth (Lymantria disp ar) larval gut aminopeptidases, APN1 and lambda APN2, were cloned and seque nced. The 3.4 kilobasepair cDNA of APN1 which encodes a 1017 amino acid pre pro-protein corresponds to the previously-identified gypsy moth APN (APN-1) that specifically binds the Cry1Ac delta-endotoxin of Bacillus thuringiens is. Analysis of the primary structure of APN1 revealed a cluster of five po tential N-linked glycosylation sites near the N-terminus and a C-terminal s equence characteristic of a putative glycosylphosphatidyl-inositol (GPI) an chor signal sequence. The cDNA of APN1 encodes the N-terminal peptide seque nce and nine internal sequences obtained from the purified brush border mem brane vesicle Cry1Ac receptor by protein sequencing. The lambda APN2 cDNA e ncodes a shorter protein with 51% similarity to APN1 that also appears to h ave a GPI anchor signal sequence. Expression of the APN1 cDNA in a baculovi rus vector was confirmed by immunoblotting. Published by Elsevier Science L td.