棉铃虫C型凝集素抑制多角体病毒体内增殖

为探究C型凝集素（C-type lectin）在病毒传播中的可能作用，采用半定量RT-PCR法检测了棉铃虫Helicoverpa armigera不同C型凝集素在核型多角体病毒（nuclearpolyhedrosis virus，NPV）感染后的表达变化，并通过real-time qPCR和RNA干扰技术研究了NPV在棉铃虫体内的增殖状况及对棉铃虫致死率的影响。结果显示，在感染NPV后，棉铃虫血细胞C型凝集素Ha-lectin1和Ha-lectin5基因表达变化明显，其中Ha-lectin1在血细胞和脂肪体中的表达显著上调；注射dsRNA后，Ha-lectin1基因相对于actin的表达量均值由0.19下降到0.04，下降幅度达79%，显示Ha-lectin1基因被成功干扰。随着Ha-lectin1基因的沉默，病毒滴度由0.0015快速升高到1.95，棉铃虫的死亡率也随之增加到97.7%。表明C型凝集素能够抑制NPV在棉铃虫体内的增殖。

A C-type lectin from the cotton bollworm inhibiting NPV proliferation in vivo

In order to explore the possible role of C-type lectin in viral dissemination, the expression level of the cotton bollworm C-type lectins was detected after nuclearpolyhedrosis virus (NPV) challenge; meanwhile, real-time qPCR and RNAi were used to study the change in proliferation of NPV and mortality of the cotton bollworm. The results showed that the expression of hemocytes Ha-lectin1 and Ha-lectin5 changed obviously after NPV infection, and Ha-lectin1 was significantly up-regulated in hemocytes and fat body. The mean of Ha-lectin1 relative to actin expression decreased from 0.19 to 0.04 after dsRNA injection, dropping by 79%, which indicated that Ha-lectin1 expression was successfully interfered. With the silence of hemocyte Ha-lectin1, the virus titers increased rapidly from 0.0015 to 1.95, accompanied with a 97.7% increase of mortality in the cotton bollworm. The results suggested that C-type lectin could inhibit NPV proliferation in Helicoverpa armigera.