McTaggart Seanna J, Hannah Tidbury, Bridgett Stephen, Garbutt Jennie S, Kaur Gaganjot, Boots Mike
Institute of Evolutionary Biology, School of Biological Sciences, Ashworth Laboratories University of Edinburgh, Edinburgh, EH9 3JT, UK.
Centre for Immunity, Infection and Evolution, School of Biological Sciences, Ashworth Laboratories University of Edinburgh, Edinburgh, EH9 3JT, UK.
BMC Genomics. 2015 Apr 17;16(1):310. doi: 10.1186/s12864-015-1499-z.
Little is known about invertebrate responses to DNA viruses. Here, we infect a commercially important pest moth species Plodia interpunctella with its naturally infecting DNA virus. We sequenced, assembled and annotated the complete transcriptome of the moth, and a partial transcriptome of the virus. We then tested for differential gene expression between moths that were exposed to the virus and controls.
We found 51 genes that were differentially expressed in moths exposed to a DNA baculovirus compared to controls. Gene set enrichment analysis revealed that cuticle proteins were significantly overrepresented in this group of genes. Interestingly, 6 of the 7 differentially expressed cuticle proteins were downregulated, suggesting that baculoviruses are able to manipulate its host's response. In fact, an additional 29 of the 51 genes were also downregulated in exposed compared with control animals, including a gram-negative binding protein. In contrast, genes involved in transposable element movement were upregulated after infection.
We present the first experiment to measure genome-wide gene expression in an insect after infection with a natural DNA virus. Our results indicate that cuticle proteins might be key genes underpinning the response to DNA viruses. Furthermore, the large proportion of genes that were downregulated after viral exposure suggests that this virus is actively manipulating the insect immune response. Finally, it appears that transposable element activity might increase during viral invasion. Combined, these results provide much needed host candidate genes that respond to DNA viral invaders.
关于无脊椎动物对DNA病毒的反应，我们了解得很少。在此，我们用一种自然感染的DNA病毒感染了一种具有商业重要性的害虫蛾类——印度谷螟。我们对该蛾类的完整转录组以及病毒的部分转录组进行了测序、组装和注释。然后，我们测试了接触病毒的蛾类与对照蛾类之间的基因表达差异。
我们发现，与对照相比，在接触DNA杆状病毒的蛾类中有51个基因表达存在差异。基因集富集分析表明，表皮蛋白在这组基因中显著富集。有趣的是，7个差异表达的表皮蛋白中有6个表达下调，这表明杆状病毒能够操纵其宿主的反应。事实上，与对照动物相比，在接触病毒的动物中，51个基因中的另外29个也下调了，包括一种革兰氏阴性结合蛋白。相反，参与转座元件移动的基因在感染后上调。
我们首次进行了一项实验，以测量昆虫在感染天然DNA病毒后的全基因组基因表达。我们的结果表明，表皮蛋白可能是对DNA病毒反应的关键基因。此外，病毒接触后大量基因下调表明这种病毒正在积极操纵昆虫的免疫反应。最后，在病毒入侵期间转座元件活性似乎可能增加。综合起来，这些结果提供了急需的对DNA病毒入侵者有反应的宿主候选基因。
