抗Bt棉棉铃虫幼虫Bt受体氨肽酶N(APN2)基因克隆  

Molecular Cloning of Bt Toxin Receptor Aminopeptidase N From Larvae of Helicoverpa armigera Hübner Resistant to Bacillus thuringiensis

作　　者：苏建亚[1] 周晓梅[1] 沈晋良[1] 

机构地区：[1]南京农业大学农业部病虫监测与治理重点开放实验室农药科学系,南京210095

出　　处：《中国生物工程杂志》2004年第10期59-62,共4页China Biotechnology

基　　金：国家自然科学基金项目 (3 0 2 70 889);教育部博士点基金项目(2 0 0 0 0 3 0 70 3 )

摘　　要：通过对Bt棉抗性和敏感棉铃虫幼虫中肠氨肽酶N的克隆和测序 ,鉴定了氨肽酶N基因家族的 1个成员Haapn2 ,其cDNA序列具有 32 0 9个核苷酸 ,含有 30 96bp的开放阅读框 ,编码产生1 0 32个氨基酸的蛋白质。其推定氨基酸序列具有锌结合模体HEXXHX18E ,N 末端具有 1 7个氨基酸的疏水性信号序列 ,C 末端还具有 2 2个氨基酸的糖基磷酯酰肌醇 (GPI)添加信号肽。比对抗性和敏感棉铃虫cDNA的开放阅读框 ,抗性品系的开放阅读框中 ,有 5 7个点突变 ,共导致了 1 5个氨基酸的改变 ,其中 2个突变 (谷氨酰胺13 7→谷氨酸、缬氨酸173 →苏氨酸 )位于Cry1A毒素结合区域 ,可能与棉铃虫对转Bt基因棉产生抗性有关。报道的氨肽酶cDNA序列已提交GenBank ,AY346383和AY2 795 35分别是Bt抗性和敏感品系的Haapn2。cDNA of aminopeptidase N(APN) from both Bt cotton susceptible and resistant strains of cotton bollworm (CBW) Helicoverpa armigera Hübner,were cloned and sequenced.One member Haapn2 in aminopeptidase N family was identified.This APN had 3209 nucleotides with a 3096bp open reading frame that encodes 1032 amino acids.Hydrophobic signal sequence with 17 amino acids in N terminal region and a GPI anchor signal sequence with 22 amino acids in C terminal region were found in the deduced amino sequence which had the consensus zinc binding/gluzincin motif HEXXHX 18 E.Alignment and comparison of cDNA sequences from Bt cotton susceptible and resistant cotton bollworm revealed some nucleotide differences in the open reading frames.In the open reading frame of Haapn2 in resistant strain there were 57 point mutations,which resulted in 15 amino acid changes in putative protein sequence of aminopeptidases,Two of these mutations:Gln 137 →Glu、Val 173 →Thr were located within Cry1A toxin binding region that was probably related with the resistance of CBW to transgenic Bt cotton.The sequences reported in this paper have been deposited in the GenBank database (accession number AY346383 and AY279535 for Haapn2 from Bt resistant and susceptible strain).

关 键 词：抗B 开放阅读框 氨肽酶N 氨基酸 受体 A毒素 APN 棉铃虫 BT棉 幼虫 

分 类 号：Q78[生物学—分子生物学] S435[农业科学—农业昆虫与害虫防治]