关键词：
蝶蛹金小蜂;菜粉蝶;肌动蛋白;肌动蛋白解聚因子;微管蛋白;转录调控
摘 要：
为揭示蝶蛹金小蜂Pteromalus puparum抑制寄主菜粉蝶Pieris rapae血细胞免疫反应的分子机制,克隆了菜粉蝶肌动蛋白、肌动蛋白解聚因子及微管蛋白cDNA,并研究了蝶蛹金小蜂寄生对其转录水平的影响。结果显示:菜粉蝶肌动蛋白cDNA ORF为1131bp,编码377aa,预测分子量为41.78kDa,pI为5.29,与其他昆虫肌动蛋白的相似性非常高,在90%以上。氨基酸组成特点和系统进化分析表明,克隆到的菜粉蝶肌动蛋白基因属细胞质型肌动蛋白。菜粉蝶肌动蛋白解聚因子cDNA全长为1243bp,ORF为447bp,编码149aa,预测分子量为16.97kDa,pI为7.11,与家蚕Bombyx mori、赤拟谷盗Tribolium castaneum、意大利蜜蜂Apis mellifera和桑粉介壳虫Maconellicoccus hirsutus肌动蛋白解聚因子的相似性分别为97%,87%,89%和72%。菜粉蝶微管蛋白cDNA全长为1757bp,ORF为1344bp,编码448aa,预测分子量为50.38kDa,pI为4.86,与家蚕β型微管蛋白1,2,3和4的相似性分别为97%,97%,87%和93%。系统进化分析表明,克隆到的菜粉蝶微管蛋白基因属β型微管蛋白。RT-PCR分析表明,蝶蛹金小蜂寄生能抑制肌动蛋白、肌动蛋白解聚因子及微管蛋白基因在菜粉蝶蛹血细胞中的转录水平。由此推断蝶蛹金小蜂调控寄主血细胞骨架相关蛋白基因的转录是该蜂抑制寄主血细胞免疫反应的分子机制之一。
译 名：
Transcriptional changes of cytoskeleton related proteins of Pieris rapae(Lepidoptera:Pieridae) after parasitization by the endoparasitoid wasp Pteromalus puparum(Hymenoptera:Pteromalidae)
作 者：
ZHU Jia-Ying1,2,YE Gong-Yin1,FANG Qi1,LI Yan-Min1,HU Cui1(1. Institute of Insect Sciences,Zhejiang University,Hangzhou 310029,China; 2. Key Laboratory of Forest Disaster Warning and Control of Yunnan Province,Faculty of Conservation Biology,Southwest Forestry University,Kunming 650224,China)
关键词：
Pteromalus puparum; Pieris rapae; actin; actin depolymerisation factor; tubulin; transcriptional regulation
摘 要：
To reveal the molecular mechanism of cellular immune response of Pieris rapae suppressed by Pteromalus puparum,the cDNAs of actin,actin depolymerisation factor and tubulin from P. rapae were cloned and their transcription regulated by parasitization of P. puparum was investigated. The results indicated that P. rapae actin cDNA contained an open reading frame of 1 131 bp encoding for 377 amino acid residues with the predicted molecular mass and pI of 41.78 kDa and 5.29,respectively. The homology of P. rapae actin with other insect actins was greater than 90% in amino acids. P. rapae actin was classified as the cytoplasmic type by absence of muscle-specific amino acids and phylogenetic tree analysis. The 1 243 bp cDNA sequence of P. rapae actin depolymerisation factor contained an open reading frame of 447 bp encoding a neutral (pI 7.11) protein of 149 amino acids with a predicted molecular mass of 16.97 kDa,sharing 97%,87%,89% and 72% homology with the homologous sequences of Bombyx mori,Tribolium castaneum,Apis mellifera and Maconellicoccus hirsutus,respectively. Nucleotide sequence analysis of P. rapae tubulin showed the full length cDNA of 1 757 bp with the open reading frame of 1 344 bp encoding a protein of 448 amino acids with a predicted molecular weight of 50.38 kDa and a pI of 4.86. The cDNA-deduced amino acid sequence of P. rapae tubulin showed 97%,97%,87% and 93% homology with that of B. mori beta-tubulin 1,2,3 and 4,respectively. P. rapae tubulin was classified as beta type by phylogenetic evolution analysis. The RT-PCR analysis showed that P. rapae actin,actin depolymerisation factor and tubulin genes were all affected by P. puparum parasitization,as indicated by decreased transcription. It is so inferred that the molecular mechanism of cellular immune response of P. rapae inhibited by P. puparum might be the result of the expression of cytoskeleton related protein genes of P. rapae regulated by P. puparum.
