Department of Plant Pathology, Kansas State University, Manhattan, KS 66506, USA.
Insect Mol Biol. 2011 Apr;20(2):225-42. doi: 10.1111/j.1365-2583.2010.01060.x. Epub 2011 Jan 4.
The corn planthopper, Peregrinus maidis, causes direct feeding damage to plants and transmits Maize mosaic rhabdovirus (MMV) in a persistent-propagative manner. MMV must cross several insect tissue layers for successful transmission to occur, and the gut serves as an important barrier for rhabdovirus transmission. In order to facilitate the identification of proteins that may interact with MMV either by facilitating acquisition or responding to virus infection, we generated and analysed the gut transcriptome of P. maidis. From two normalized cDNA libraries, we generated a P. maidis gut transcriptome composed of 20,771 expressed sequence tags (ESTs). Assembly of the sequences yielded 1860 contigs and 14,032 singletons, and biological roles were assigned to 5793 (36%). Comparison of P. maidis ESTs with other insect amino acid sequences revealed that P. maidis shares greatest sequence similarity with another hemipteran, the brown planthopper Nilaparvata lugens. We identified 202 P. maidis transcripts with putative homology to proteins associated with insect innate immunity, including those implicated in the Toll, Imd, JAK/STAT, Jnk and the small-interfering RNA-mediated pathways. Sequence comparisons between our P. maidis gut EST collection and the currently available National Center for Biotechnology Information EST database collection for Ni. lugens revealed that a pathogen recognition receptor in the Imd pathway, peptidoglycan recognition protein-long class (PGRP-LC), is present in these two members of the family Delphacidae; however, these recognition receptors are lacking in the model hemipteran Acyrthosiphon pisum. In addition, we identified sequences in the P. maidis gut transcriptome that share significant amino acid sequence similarities with the rhabdovirus receptor molecule, acetylcholine receptor (AChR), found in other hosts. This EST analysis sheds new light on immune response pathways in hemipteran guts that will be useful for further dissecting innate defence response pathways to rhabdovirus infection.
玉米蚜以直接取食植物造成危害，并以持久增殖方式传播玉米线条病毒（Maize mosaic rhabdovirus，MMV）。MMV 必须穿越几种昆虫组织层才能成功传播，而肠道是病毒传播的重要屏障。为了鉴定可能通过促进获得或响应病毒感染而与 MMV 相互作用的蛋白质，我们生成并分析了玉米蚜的肠道转录组。从两个归一化的 cDNA 文库中，我们生成了一个由 20771 个表达序列标签（EST）组成的玉米蚜肠道转录组。序列组装得到 1860 个 contigs 和 14032 个 singletons，并对 5793 个（36%）序列赋予了生物学功能。玉米蚜 EST 与其他昆虫氨基酸序列的比较表明，玉米蚜与另一种半翅目昆虫褐飞虱Nilaparvata lugens 的序列相似度最高。我们鉴定了 202 个玉米蚜转录本，它们与昆虫先天免疫相关的蛋白质具有假定的同源性，包括那些与 Toll、Imd、JAK/STAT、Jnk 和小干扰 RNA 介导途径相关的蛋白质。我们的玉米蚜肠道 EST 集合与目前可用的褐飞虱国家生物技术信息中心 EST 数据库集合之间的序列比较表明，Imd 途径中的病原体识别受体，肽聚糖识别蛋白长类（PGRP-LC），存在于这两个飞虱科成员中；然而，这些识别受体在模式半翅目昆虫烟粉虱 Acyrthosiphon pisum 中缺失。此外，我们在玉米蚜肠道转录组中鉴定到与其他宿主中发现的拉沙病毒受体分子乙酰胆碱受体（AChR）具有显著氨基酸序列相似性的序列。这项 EST 分析为半翅目昆虫肠道中的免疫反应途径提供了新的认识，这将有助于进一步剖析对拉沙病毒感染的先天防御反应途径。
