›› 2010, Vol. 53 ›› Issue (10): 1077-1086.

• 研究论文 • 上一篇    下一篇

小菜蛾糖基转移酶基因的克隆、序列分析及在不同发育阶段的表达

包宏伟, 吴益东, 杨亦桦   

  • 出版日期:2010-10-20 发布日期:2010-10-20
  • 通讯作者: 杨亦桦

Molecular cloning, sequence analysis and developmental expression of the glycosyltransferase genes in the diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae)

BAO Hong-wei   

  • Online:2010-10-20 Published:2010-10-20

摘要:

根据秀丽小杆线虫Caenorhabditis elegans及其他昆虫中糖基转移酶基因的同源序列, 采用逆转录PCRreverse transcription PCR, RT-PCR)和cDNA末端快速扩增PCRrapid amplification of cDNA ends PCR, RACE-PCR)技术从小菜蛾Plutella xylostella 4龄幼虫中肠组织中获得了3个基因的全长序列, 其开放阅读框长度分别为1 383 bp, 1 230 bp 1 041 bp, 分别编码460, 409346个氨基酸, 将其分别命名为Pxbre-3, Pxbre-4 Pxbre-5 (GenBank登录号分别是GU321343, GU321344GU321345)。同源序列比对发现, 这些基因和线虫中相应的糖基转移酶基因具有较高相似度, 且具有对糖基转移酶活性起关键作用的氨基酸保守模块, 也包含类似的跨膜区。由此推测, 3个基因为小菜蛾糖基转移酶基因, 参与小菜蛾鞘糖脂的合成。实时定量PCR检测结果表明, 3个基因以及Pxbre-2在小菜蛾4龄幼虫、蛹和成虫以及4龄幼虫中肠组织均有表达, 在蛹和成虫阶段表达量较高。本实验结果为今后研究鞘糖脂是否参与小菜蛾对Bt毒素的抗性奠定了基础。

关键词: 小菜蛾, Cry毒素, 鞘糖脂, 糖基转移酶, mRNA表达

Abstract:

According to the homologous amino acid sequences in Caenorhabditis elegans and other insects, the full length cDNA sequences of 3 glycosyltransferase genes (named as Pxbre-3, Pxbre-4 and Pxbre-5) were cloned by RT-PCR and RACE-PCR from the midgut of 4th instar larvae of the diamondback moth, Plutella xylostella. The open reading frames of these genes were 1 383 bp, 1 230 bp and 1 041 bp, respectively. The deduced coding products had 460, 409 and 346 amino acids, respectively. These genes were homologous to the bre genes of Caenorhabditis elegans and had the predicted membrane-spanning regions and conserved motifs known to play key catalytic roles in glycosyltransferases. Thus, the three genes are inferred to code glycosyltransferases in P. xylostella. The mRNA expression of these three genes and Pxbre-2 was detected in different developmental stages (larva, pupa, and adult) of P. xylostella by real-time quantitative PCR, and the expression level was higher in pupa and adult. These results provide an important basis for investigating the possible involvement of glycosylphingolipid in resistance to Cry toxins in P. xylostella.

Key words: Plutella xylostella, Cry toxin, glycosylphingolipid, glycosyltransferase, mRNA expression