Huang Yinghua, Huang Jian
USDA-ARS Plant Science Research Laboratory, Stillwater, OK, United States.
Department of Plant Biology, Ecology, and Evolution, Oklahoma State University, Stillwater, OK, United States.
Front Genet. 2023 Aug 15;14:1194273. doi: 10.3389/fgene.2023.1194273. eCollection 2023.
Sorghum [ (L.) Moench] is one of the most important cereal crops grown worldwide but is often attacked by greenbug (aphid). In response to aphid attack, host plant initiates a large transcriptional reorganization, leading to activation of the host defense genes in aphid-attacked plants. In this study, our objective was to analyze defensive responses of sorghum against aphid and identify aphid resistance genes in sorghum. For the experiments, seedlings developed from an aphid resistant germplasm line (PI 550607) were divided into two groups, then, one group was infested with greenbug (( Rondani) and the other group was used as control (un-infested). In addition, seedlings of sorghum cultivar Tx 7000, a susceptible genotype, prepared under the same conditions, were used as a genetic control. Those plant samples were used to develop transcriptional profiles using the microarray method, from which 26.1% of the 1,761 cDNA sequences spotted on the microarray showed altered expression between two treatments at 4 days after infestation. Sequence annotation and molecular analysis revealed that many differentially expressed genes (DEGs) were related to direct host defense or signal transduction pathways, which regulate host defense. In addition to common responsive genes, unique transcripts were identified in response to greenbug infestation specifically. Later, a similar transcriptional profiling was conducted using the RNA-seq method, resulted in the identification of 2,856 DEGs in the resistant line with a comparison between infested and non-infested at 4 days and 4,354 DEGs in the resistant genotype compared to the susceptible genotype at 4 days. Based on the comparative analysis, the data of RNA-seq provided a support for the results from the microarray study as it was noticed that many of the DEGs are common in both platforms. Analysis of the two differential expression profiles indicate that aphid triggered dynamic defense responses in sorghum plants and sorghum plant defense against aphid is a complex process involving both general defense systems and specific resistance mechanisms. Finally, the results of the study provide new insights into the mechanisms underlying host plant defense against aphids and will help us design better strategies for effectively controlling aphid pest.
高粱[ (L.) Moench]是全球种植的最重要的谷类作物之一，但常受到麦二叉蚜（蚜虫）的侵害。作为对蚜虫攻击的响应，寄主植物会启动大规模的转录重组，导致受蚜虫攻击的植物中寄主防御基因被激活。在本研究中，我们的目标是分析高粱对蚜虫的防御反应，并鉴定高粱中的抗蚜虫基因。在实验中，将来自抗蚜虫种质系（PI 550607）的幼苗分成两组，然后，一组用麦二叉蚜（(Rondani)）侵染，另一组用作对照（未侵染）。此外，将在相同条件下制备的高粱品种Tx 7000（一种感病基因型）的幼苗用作遗传对照。使用微阵列方法对这些植物样本进行转录谱分析，在侵染后4天，微阵列上点样的1761个cDNA序列中有26.1%在两种处理之间表现出表达变化。序列注释和分子分析表明，许多差异表达基因（DEG）与直接的寄主防御或调节寄主防御的信号转导途径有关。除了常见的响应基因外，还特别鉴定出了响应麦二叉蚜侵染的独特转录本。后来，使用RNA测序方法进行了类似的转录谱分析，结果在侵染和未侵染4天的抗性品系中鉴定出2856个DEG，在4天时抗性基因型与感病基因型相比鉴定出4354个DEG。基于比较分析，RNA测序数据为微阵列研究的结果提供了支持，因为注意到许多DEG在两个平台中是共有的。对这两个差异表达谱的分析表明，蚜虫在高粱植株中引发了动态防御反应，高粱植株对蚜虫的防御是一个复杂的过程，涉及一般防御系统和特定抗性机制。最后，该研究结果为寄主植物抗蚜虫机制提供了新的见解，并将帮助我们设计更好的策略来有效控制蚜虫虫害。
