甜菜夜蛾PAP基因克隆及在高温胁迫下其表达量的变化

Cloning and Expression of PAP cDNA in the Larvae of Beet armyworm,Spodoptera exigua (Lepidoptera:Noctuidae) under High Temperature Stress

紫色酸性磷酸酯酶(purple acid phosphatase,PAP)在生物逆境胁迫中具有至关重要的作用,而在昆虫中此类基因极少见于报道。首次克隆和分析了甜菜夜蛾PAP基因cDNA 3’末端序列,在GenBank登录后,获得序列号为HM566114,其长为759个碱基对,推测编码252个氨基酸。此多肽序列具有高度保守性,其相似性分别为:埃及伊蚊(Aedes aegypti)84%;黑腹果蝇(Drosophila melanogaster)52%,赤拟谷盗(Tribolium castaneum)50%。为了研究高温对甜菜夜蛾PAP基因表达量的影响,利用RT-PCR技术,检测30℃,35℃,40℃胁迫下甜菜夜蛾2龄幼虫体内PAP基因表达量的变化,其中设对照组为25℃。结果表明:高温对甜菜夜蛾2龄幼虫PAP基因表达具有明显的诱导作用,30℃,35℃,40℃分别处理10,20 h的表达量均显著高于对照组25℃分别处理的10,20 h(P<0.05)。相比于对照组,在30℃处理20 h的表达量最高,表明PAP基因的表达与其抗高温能力之间存在一定的关系。

Purple acid phosphatase（PAP） plays a critical role of organism under adversity stress.However,little work has been reported on PAP associated with adversity stress in insect.In this study,Sexi-PAP,a partial cDNA of the 3′ end（GeneBank accession NO： HM566114） encoding purple acid phosphatase of beet armyworm,Spodoptera exigua（Hübner）was cloned,sequenced and analyzed.The cDNA is 759 bp that encodes 252 putative amino acids,which exhibited a significant similarity to purple acid phosphatase of Aedes aegypti（84%）,Drosophila melanogaster（52%） and Tribolium castaneum（50%）.Semi-quantitative RT-PCR was used to understand the effect of high temperature on the expression of PAP.The results indicated that high temperature could significantly induce the expression of PAP.The detailed results were that the PAP expression levels in the second instar larvae under 30 ℃,35 ℃,and 40 ℃ for 10 h and 20 h,respectively,were significantly higher than those of the control groups（P0.05）.Furthermore,the expression of the treatment at 30 ℃ for 20 h had the highest relative gray value,and that at 25 ℃ for 20 h was the lowest.This study has suggested the possibility physiological role of the PAP at high temperature stress.