Project description:The Ixodidea tick Dermacentor marginatus is a vector of many pathogens wide spread in Eurasia. Study of gene targets of the tick species provides insight to find novel tick protective antigen for drug development and vaccine targets. To obtain a broader picture of gene sequences and changes in expression level, we aimed to characterize the whole body transcriptome in D. marginatus adult female after engorgement and long-term starvation using RNA-seq. We have assembled and analyzed transcriptome of D. marginatus females 5 days after ecdysis, 24 h after a blood meal, and 6 months under controlled experimental conditions. Sequencing produced 30251 unigenes, of which 32% were annotated using Trinity. Gene expression was compared among groups differed by status as newly molted, starved and engorged female adult ticks. Nearly 1/3 of the unigenes in each group were differentially expressed compared to the other two group, and we found that the most numerous were proteins involved in catalytic and binding activities and apoptosis. Selected up-regulated differentially expressed genes in each group associated to protein, lipids, carbohydrate and chitin metabolism. Blood feeding and long-term starvation also caused genes differentially expressed in the defense response and antioxidant response. Finding the sequence information and expression pattern would be helpful in understanding molecular physiology of D. marginatus, and provides information for anti-tick vaccine and drug development.
Project description:In Europe, ticks are the most important vectors of diseases threatening humans, livestock, wildlife and companion animals. Nevertheless, genomic sequence information and functional annotation of proteins of the most important European tick, Ixodes ricinus, is limited. Here we present the first analysis of the I. ricinus genome and of the transcriptome of the unfed I. ricinus midgut. We combined and integrated data from genome, transcriptome and proteome. The de novo assembly of 1 billion paired-end sequences identified 6,415 putative genes providing an unprecedented insight into the I. ricinus genome. Mapping of our midgut mRNA reads to the assembled contigs let us estimate to cover around two third of the unique genomic sequences. In addition, more than 10,000 transcripts from naïve midgut were annotated functionally and/or locally. By combining the alignment-based with a motif-search based annotation approach, we could double the number of annotations throughout all groups without shifting the dataset. Moreover, 1,175 proteins expressed in the naïve midgut were identified by mass spectrometry confirming the high completeness of our transcriptome database, and 608 were significantly annotated for function and/or localization. This multiple-omics study vastly extends the publicly available DNA, RNA and protein databases for I. ricinus and ticks in general.