Abstract: The cDNA fragment of Bt Cry1 Ac toxin binding protein from the midgut of Helicoverpa assulta larva was reamplificated using RT-PCR technique. This fragment was further cloned and sequenced. The sequenced result showed that the 812 bp nucleotide sequence that encods 270 amino acid residues were in the encoding frame. Compared with APN gene sequences of Helicoverpa armigera, Helicoverpa punctigera, Heliothis virescens, Lymantria dispar, Plutella xylostella, Plodia interpunctella Rc688, Plodia interpunctella HD198, Manduca sexta and Bombyx mori, the identity were 97.0%, 90.0%, 78.0%, 63.5%, 55.0%, 60.3%, 61.2%, 55.0% and 59.0% respectively.Compared with Bt Cry1Ac binding protein amino acid sequence of Helicoverpa armigera, Heliothis virescens, Helicoverpa punctigera, Lymantria dispar, the homology of the reduced amino acid sequence of Helicoverpa assulta APN the gene were 95.6%, 81.0%, 82.7% and 55.7% respectively. Moreover the encoding amino acid sequence belongs to the amniopeptidase N (APN) family which is associated with insect resistance to Bt.

Key words: Helicoverpa assulta Guenè, e, Bt, Binding-protein, cDNA, Cloning

CLC Number: 

• S433