EcR-RNAi和印楝素处理斜纹夜蛾幼虫诱导腹足发育受阻表型(英)简

蜕皮激素是一种可以诱导一系列变态发育关键过程的昆虫蜕皮调节激素,
与蜕皮激素受体结合以后与配体蛋白~Usp~作用形成一个复合体发挥作用.
通过兼并引物克隆获得斜纹夜蛾一个~600~bp~的~EcR
cDNAs~片段编码~200~个氨基酸, 斜纹夜蛾是东亚地区一种主要的农作物害虫.
利用这段序列设计了~EcR-dsRNA~通过注射幼虫的实验来分析~EcR~基因在不同发育阶段的功能.
同时利用印楝素喂食RNAi注射的幼虫观察其与正常对照组有何发育差异.
结果显示~EcR RNAi~会影响正常的蜕皮过程并导致不完成蛹化, 在~EcR
RNAi~注射并喂食印楝素的实验组,
幼虫出现生长迟缓、发育进程紊乱和腹足发育不正常等现象,
由此推测印楝素和~EcR RNAi~或许影响了蜕皮级联调控通路,
由此引发变态发育过程中组织重建紊乱.

EcR-RNAi and azadirachtin treatments induced the abnormal proleg development in Spodoptera litura.

Ecdysone is the insect molting hormone which induces a
series of events critical for ecdysis, beginning with the formation
of a complex between ecdysteroid receptor (EcR) and its partner
protein, ultraspiracle (Usp). We cloned a 600~bp partial cDNAs
encoding 200 amino acids EcR protein by degenerate primers from the
common cutworm, \textit{Spodoptera litura}, a destructive
agricultural pest insect in East Asia. We used this fragment to
design the EcR-dsRNA to interfere the corresponding gene to analysis
the change in different development stages. Using the Azadirachtin
(Az) feeding the RNAi injected larvae to observe the development
difference with normal control. Results indicated that the EcR RNAi
interference the normal ecdysis and result in incomplete pupal molt.
In the Az treatment after EcR RNAi injection, the larvae stunt
growth and development program were disturbed and observed abnormal
proleg phenotype. We deduced that Az and EcR RNAi maybe influence
the key genes and inhibit the ecdysone cascade modulate pathway,
which result in the disorder of tissue remodeling in
molting.