Wilforine,分离自雷公藤的倍半萜生物碱的化合物,对Mythimnaseparata具有出色的杀虫活性。为了阐明雷公藤的作用机制,研究了分离分枝杆菌的质膜钙转运ATP酶(PMCA)和肌醇1,4,5-三磷酸受体(IP3R)。结果表明,MsIP3R和MsPMCA的开放阅读框长分别为8118bp和3438bp,以及编码2706和1146个氨基酸,分别。多序列比对和系统发育分析表明,MsIP3R和MsPMCA与其他昆虫的IP3R和PMCA具有较高的同源性,但与哺乳动物的相似性很低,这意味着IP3R和PMCA有可能成为哺乳动物和昆虫之间具有高选择性的新型杀虫剂靶标。MsIP3R和MsPMCA基因都存在于分离分枝杆菌的整个生命周期中,并且主要在五龄幼虫和成虫的体细胞肌肉中表达。PMCA沉默的M.separata对苜蓿的敏感性显着低于正常的M.separata,这说明了PMCA可能是wilforine的目标之一。然而,与正常分离菌的敏感性相比,IP3R沉默的分离菌对紫藤的敏感性没有显着变化,这表明wilforine可能不与IP3R蛋白相互作用。这些发现为阐明雷公藤的杀虫机理提供了线索。
Wilforine, a compound of sesquiterpene alkaloids isolated from Tripterygium wilfordii, exhibits excellent insecticidal activity against Mythimna separata. In order to clarify the action mechanism of wilforine, the plasma membrane calcium transporting ATPase (
PMCA) and inositol 1,4,5-trisphosphate receptor (IP3R) from M. separata were studied. Results showed that the open reading frame of MsIP3R and MsPMCA were 8118 bp and 3438 bp in length, as well as encoded 2706 and 1146 amino acids, respectively. Multiple sequence alignment and phylogenetic analysis revealed that the MsIP3R and MsPMCA had high homology with the IP3R and
PMCA of other insects, but had low similarity with those of mammals, which means the IP3R and
PMCA have potential to be the novel targets of insecticides with high selectivity between mammals and insects. Both MsIP3R and MsPMCA genes existed throughout the life cycle of M. separata, and were all predominantly expressed in somatic muscle of fifth-instar larvae and the adults. The susceptibilities of
PMCA-silenced M. separata to wilforine were significantly lower than that of the normal M. separata, which illustrates that
PMCA could be one of the targets of wilforine. However, the susceptibilities of IP3R-silenced M. separata to wilforine did not change significantly compared with the susceptibilities of normal M. separata, which shows that wilforine may not interact with the IP3R protein. These findings provide clues for elucidating the insecticidal mechanism of wilforine.