Molecular Cloning Of CDNA Encoding Bt Cry1Ac Toxin Binding Protein From The Midgut Of Helicoverpa Assulta Guenée

The cDNA fragment from the midgut of Helicoverpa assulta larva was reamplificated by RT-PCR technique. This fragment was further cloned and sequenced. The sequenced result showed that the 812bp nucleotide acids sequences that encoded 270 amino acid residues were in encoding frame. Compared with APN gene sequences of Helicoverpa armigera, Helicoverpa punctigera , Heliothis virescens,Lymantria dispar, Plutella xylostella, Plodia interpunctella Rc688, PlodiainlerpunctellaHD198, Manduca sexta and Bombyx mori. The identify was 97%, 90%, 78%, 63.5%, 55%, 60.3%, 61.2%, 55%, 59% respectively .Compared with Bt CrylAc binding protein amino acid sequence of Helicoverpa armigera, He Hot his virescens, Helicoverpa punctigera Lymanlria dispar, The homology of the reduced amino acid sequence of Helicoverpa assulta APN gene was 95.6%,81%,82.7%,55.7% respectively.Moreover the encoding amino acid sequence belong to amniopeptidase N (APN) family has a associated with insect resistance to Bt.Amplifmg the cDNA fragment encoding APN from the midgut Helicoverpa assulta instar 1-6 larva by RT-PCR. The result show: the apparent band appear from instar 1 to 6 larva. In other word, APN gene all express at instarl to 6 larva in mRNA level, Bt has a control effect in all instar, this is the first to stuy the express of Helicoverpa assulta APN gene at time sequence in mRNA level...