State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining 810016, PR China; College of Agriculture and Animal Husbandry, Qinghai University, Xining 810016, PR China.
National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 0808555, Hokkaido, Japan.
Infect Genet Evol. 2023 Apr;109:105409. doi: 10.1016/j.meegid.2023.105409. Epub 2023 Feb 10.
The hard tick Haemaphysalis qinghaiensis is the vector of a wide variety of infectious agents, such as spirochetes and other bacteria as well as viruses in the western plateau of China. Tick midgut is the key tissue involved in the host-pathogen-vector interface. Multiple midgut proteins are related to key functions in blood digestion, tick survival, and tick-borne pathogen transmission. However, information on the sex-specific proteins expressed in the midgut tissue of H. qinghaiensis for which the genome has not been sequenced is limited. Hence, we assembled and characterized the transcriptome of the H. qinghaiensis midgut and identified the differentially expressed genes (DEGs) in female and male ticks. The sequencing of the mRNA for this nonmodel species is essential for producing a protein database for mass spectrometry-based identification. Here, we combined high-throughput parallel sequencing and label-free quantitative proteomics analysis to extensively characterize the tick midgut using massive RNA sequencing and mass spectrometry, which allowed the detection of genes and proteins. A total of 279,186 transcripts were annotated into 125,790 coding sequences (CDSs), which were manually curated into 96 different gene families. A total of 12,837 DEGs between the two sexes were found by RNA-seq analysis. Of these, 5401 were upregulated genes, while 7436 were downregulated genes. The most common molecular functions were those related to the endocrine system, translation, signal transduction, transport, and catabolism. Meanwhile, the most common biological processes were related to cellular processes, metabolic processes, cellular anatomical entities, and cargo receptor activities. An analysis of the label-free protein quantitation dataset showed 272 upregulated proteins and 46 downregulated proteins when the fold-change was >2.0 (LC-MS/MS). Association analysis of the transcriptome and proteome with GO functional enrichment showed that the majority of the genes (proteins) were those related to catalytic activity, binding, cellular processes, metabolic processes, and responses to stimuli. This study aims to elucidate the digestive physiology of H. qinghaiensis as well as its physiological sexual dimorphism. This will allow the identification of protein candidates with physiological importance that could be used as targets to control the vector as well as the transmission of tick-borne pathogens to humans and animals.
硬蜱青海血蜱是中国西部高原多种传染性病原体的媒介，如螺旋体和其他细菌以及病毒。蜱的中肠是涉及宿主-病原体-媒介界面的关键组织。多种中肠蛋白与血液消化、蜱生存和蜱传病原体传播的关键功能有关。然而，对于基因组尚未测序的青海血蜱的中肠组织中表达的性别特异性蛋白质的信息是有限的。因此，我们组装并表征了青海血蜱中肠的转录组，并鉴定了雌性和雄性蜱中的差异表达基因（DEGs）。为了产生基于质谱的鉴定的蛋白质数据库，对这种非模型物种的 mRNA 进行高通量平行测序是必不可少的。在这里，我们结合高通量平行测序和无标记定量蛋白质组学分析，使用大量 RNA 测序和质谱对蜱的中肠进行了广泛的特征描述，从而可以检测到基因和蛋白质。总共注释了 279186 个转录本到 125790 个编码序列（CDS），这些 CDS 被手动整理成 96 个不同的基因家族。通过 RNA-seq 分析发现两性之间共有 12837 个 DEGs。其中，5401 个为上调基因，7436 个为下调基因。最常见的分子功能是与内分泌系统、翻译、信号转导、运输和分解代谢有关的功能。同时，最常见的生物学过程与细胞过程、代谢过程、细胞解剖实体和货物受体活性有关。无标记蛋白定量数据集的分析表明，当折叠变化>2.0（LC-MS/MS）时，有 272 个上调蛋白和 46 个下调蛋白。与 GO 功能富集的转录组和蛋白质组关联分析表明，大多数基因（蛋白）与催化活性、结合、细胞过程、代谢过程和对刺激的反应有关。本研究旨在阐明青海血蜱的消化生理学及其生理性别二态性。这将有助于鉴定具有生理重要性的蛋白质候选物，这些候选物可作为控制媒介以及蜱传病原体向人类和动物传播的目标。
