Guangzhou City Key Laboratory of Subtropical Fruit Tree Outbreak Control, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, People's Republic of China.
Department of Entomology, Kansas State University, Manhattan, KS 66506, USA.
J Proteomics. 2021 Apr 30;238:104136. doi: 10.1016/j.jprot.2021.104136. Epub 2021 Feb 22.
Salivary secretions play critical roles in interactions among insects, insect-vectored pathogens, and host plants. The Asian citrus psyllid Diaphorina citri is a sap-sucking Hemipteran that serves as a vector for Candidatus Liberibacter asiaticus, the causal agent of citrus greening disease ("Huanglongbing" or HLB). D. citri continuously injects saliva into host plants using specialized stylets so as to feed and transmit the HLB pathogen. Knowledge on the composition and function of salivary proteins of this pest is very limited. In this study, proteomic and transcriptomic approaches were adopted to characterize the protein composition of the saliva and salivary glands in D. citri. A total of 246 and 483 proteins were identified in saliva and dissected salivary glands, respectively, via LC-MS/MS analyses. Comparative analyses of the identified proteins were performed between D. citri and other reported Hemipteran insect species. Transcription levels of the genes coding for the identified proteins were determined via RNA-sequencing among different tissues including salivary glands and other digestive tissues. Identification of putative effectors that are expressed exclusively or abundantly in salivary glands provides the foundation for future functional studies towards the understanding of their roles in interactions among D. citri, HLB pathogen, and their citrus host. BIOLOGICAL SIGNIFICANCE: This is a systematic analysis on proteins in saliva and dissected salivary glands. A high percentage of novel proteins have been identified due to the large amounts of samples collected. This report gives a more comprehensive repertoire of potential effector proteins that may be possibly involved in modulating host defense, altering nutrient metabolism, and facilitating Ca. L. asiaticus transmission.
唾液在昆虫、昆虫媒介病原体和宿主植物之间的相互作用中起着至关重要的作用。亚洲柑橘木虱 Diaphorina citri 是一种吸食汁液的半翅目昆虫，它是 Candidatus Liberibacter asiaticus 的媒介，后者是柑橘黄龙病（“黄龙病”或 HLB）的病原体。D. citri 使用专门的口器不断将唾液注入宿主植物中，以进食和传播 HLB 病原体。关于这种害虫唾液蛋白的组成和功能的知识非常有限。在这项研究中，采用蛋白质组学和转录组学方法来描述 D. citri 唾液和唾液腺中的蛋白质组成。通过 LC-MS/MS 分析，分别在唾液和解剖的唾液腺中鉴定出 246 和 483 种蛋白质。对鉴定出的蛋白质进行了 D. citri 与其他报道的半翅目昆虫物种之间的比较分析。通过 RNA-seq 测定了编码鉴定出的蛋白质的基因在包括唾液腺和其他消化组织在内的不同组织中的转录水平。鉴定出仅在唾液腺中表达或大量表达的假定效应子为未来的功能研究提供了基础，以了解它们在 D. citri、HLB 病原体及其柑橘宿主之间相互作用中的作用。生物学意义：这是对唾液和解剖的唾液腺中的蛋白质进行的系统分析。由于收集了大量的样本，因此鉴定出了很高比例的新蛋白质。本报告提供了更全面的潜在效应蛋白库，这些蛋白可能参与调节宿主防御、改变营养代谢和促进 Ca. L. asiaticus 传播。
