野桑蚕各发育时期酚氧化酶原基因的表达谱分析

酚氧化酶在昆虫的免疫防御机制中起着非常重要的作用。利用在GenBank上登录的野桑蚕酚氧化酶原基因的cDNA序列,设计正反向特异引物,通过半定量RT-PCR技术检测了酚氧化酶原基因PPO1及PPO2在野桑蚕不同发育时期(蚁蚕、一龄、二龄、三龄、四龄、五龄1~6 d、预化蛹和蛹)的转录表达活性。结果表明,PPO1基因除了五龄1 d无表达及二龄表达量较低外,其他时期的表达量均较高。PPO2基因在野桑蚕的不同发育时期中均有表达,并且没有明显的差异。说明在野桑蚕的不同发育时期,PPO1基因的表达是特异性的,而PPO2基因的表达是非特异的。

Expression Profile Analysis of Prophenoloxidase Gene in Different Development Stages of Bombyx mandarina

Abstract Phenoloxidase plays very important roles in defense mechanisms of insect immunity.The forward and reverse specific primers were designed according to the cDNA sequence of prophenoloxidase gene of Bombyx mandarina in GenBank.Semi-quantitative RT-PCR was used to determine the transcriptional expression activity of prophenoloxidase gene in different developmental stages,including newly hatched larva,1st instar larvae,2nd instar larvae,3rd instar larvae,4th instar larvae,1-6 days of 5th instar larvae,prepupa and pupae.The results revealed that PPO 1 gene expressed at high levels all the other stages except no transcription found in 5th instar larvae and low transcription detected in 2nd instar larvae,however,the transcript of PPO 2 gene can be detected in all the different development stages and showed no significant difference.Taken together,it indicated that PPO 1 gene was specifically expressed during the different developmental stages while PPO 2 showed no specificity.These results provide basis for further study in prophenoloxidase gene of Bombyx mandarina.the function of prophenoloxidase gene in Bombyx mandarina.