亚洲玉米螟免疫凝集素基因的克隆、序列分析及组织表达(英文)

Molecular cloning,sequence analysis and tissue expression of immulectin gene from the Asian corn borer,Ostrinia furnacalis (Lepidoptera:Pyralidae)

C型凝集素作为模式识别分子可以识别部分脂多糖(LPS),进而参与昆虫细胞的防御反应。本文通过RT-PCR和3′/5′RACE技术从亚洲玉米螟Ostriniafurnacalis 5龄幼虫血细胞中克隆得到免疫凝集素基因(OfIML)。OfIMLmRNA全长为1241 bp,其中开放读码框(ORF)为924 bp,编码307个氨基酸(aa),分子量约为34.65 ku。与其它昆虫的C型凝集素比对分析结果显示,OfIML属于鳞翅目免疫凝集素,并且含有一个独特的结构特征,即一前一后2个糖识别域,氨基末端(CRD1,aa#1-135)和羧基末端(CRD2,aa#136-287)。RT-PCR检测OfIML在幼虫组织中的分布结果表明,其在血细胞、表皮、脂肪体、中肠、马氏管和气管中都有表达。OfIML GenBank登录号为ABZ81710。OfIML是一种昆虫免疫凝集素,含有2个糖识别域,根据其分子结构及在组织分布中的结果显示可能在亚洲玉米螟的免疫反应中起重要作用。

C-type lectin, a kind of pattern recognition molecule, recognizes the lipid A portion of lipopolysaccharide （LPS） and participates the cellular defense reaction in insects. In this paper, an immulectin （OflML）, C-type lectin with two carbohydrate-recognition domains, was cloned by reverse-transcription PCR （RT-PCR） and Y/5＇RACE from the larval hemocytes of corn borer, Ostriniafurnacalis. The eDNA of OflML is 1 241 base pairs in length, and contains an open reading frame （ORF） of 924 nucleotides, which encoding a protein of 307 amino acids with a predicted moleculannass of approximately 34.65 ku. Alignment of OflML with C-type lectins of other insects indicates that OflML is a member of Lepidoptera immulectins. OflML possesses two carbohydrate-recognition domains （CRDs）, an amino-terminal domain, CRD1 （residues 1-135）, and a carboxyl-terminal domain, CRD2 （residues 136-287）. RT-PCR analyses shows that OflML is expressed in cuticle, fat body, midgut, tracheae, and malpigbian tubules, especially in hemocytes. The eDNA sequence has been deposited with GenBank under accession No. ABZ81710. OflML isa kind of insect immunlectin, which contains two carbohydrate-recognition domains, and it possibly plays an important role during the immune reaction of O. furnaclis depending on its molecular structure and expression in tissues.