HearNPV侵染对棉铃虫中肠碱性磷酸酶活性及表达水平的影响

Effects of HearNPV infection on the enzyme activity and gene expression of alkaline phosphatase from midgut of Helicoverpa armigera

【目的】通过研究棉铃虫核型多角体病毒(HearNPV)感染宿主昆虫后对宿主中肠碱性磷酸酶(ALP)活性与基因表达水平的影响,明确病毒在侵染宿主过程中对宿主昆虫中肠ALP的调控机理。【方法】采用不同剂量的HearNPV感染3龄棉铃虫,测定感染后不同时间昆虫中肠ALP酶活性及其编码基因表达水平,分析病毒感染试虫与未感染健康试虫的ALP活性和编码基因表达水平上的差异。【结果】HearNPV感染后,能够显著抑制ALP的活性,且抑制作用与感染病毒的剂量和感染后时间的增加呈正相关。ALP活性的下降与病毒下调其编码基因ALP的表达水平有关。【结论】HearNPV感染其宿主昆虫的过程中导致宿主ALP活性显著下降,该过程可能协助病毒粒子侵染宿主。病毒对ALP活性的抑制作用机理之一是下调了ALP编码基因的表达水平。

【Objective】 The principles of viral infection on enzyme activity and gene expression for alkaline phosphatase from midgut of host insect were studied by experiments on Helicoverpa armigera larvae infected with H.armigera nucleopolyhedrovirus（HearNPV）.【Method】 The enzyme activity and gene expression level were determined at different stages after viral infection with different titers.Comparison of viral infection groups and control group was carried out to reveal the difference between infected larvae and healthy larvae.【Result】 The results indicated that the ALP activity and its gene expression level were inhibited significantly by HearNPV infection and this inhibition strength was correlated with viral infection titer and the time spent after infection.【Conclusion】 The viral invasion to host cell could be facilitated by inhibition on ALP activity.The inhibition of ALP was likely caused by the fact that viral infection decreased ALP expression.