An insight into the sialome, mialome and virome of the horn fly, Haematobia irritans

Abstract

Background The horn fly ( Haematobia irritans ) is an obligate blood feeder that causes considerable economic losses in livestock industries worldwide. The control of this cattle pest is mainly based on insecticides; unfortunately, in many regions, horn flies have developed resistance. Vaccines or biological control have been proposed as alternative control methods, but the available information about the biology or physiology of this parasite is rather scarce. Results We present a comprehensive description of the salivary and midgut transcriptomes of the horn fly ( Haematobia irritans ), using deep sequencing achieved by the Illumina protocol, as well as exploring the virome of this fly. Comparison of the two transcriptomes allow for identification of uniquely salivary or uniquely midgut transcripts, as identified by statistically differential transcript expression at a level of 16 x or more. In addition, we provide genomic highlights and phylogenetic insights of Haematobia irritans Nora virus and present evidence of a novel densovirus, both associated to midgut libraries of H. irritans . Conclusions We provide a catalog of protein sequences associated with the salivary glands and midgut of the horn fly that will be useful for vaccine design. Additionally, we discover two midgut-associated viruses that infect these flies in nature. Future studies should address the prevalence, biological effects and life cycles of these viruses, which could eventually lead to translational work oriented to the control of this economically important cattle pest. Electronic supplementary material The online version of this article (10.1186/s12864-019-5984-7) contains supplementary material, which is available to authorized users.

Revisiting the sialome of the cat flea Ctenocephalides felis

“…Together, they represent 41.4% of all secreted transcripts and ~25.4% of all secreted proteins ( Table 2 ). These values are similar to those found in other sialomes [ 37 , 38 , 40 , 76 ] and perhaps reflect a hidden pharmacological potential existing within the salivary glands of hematophagous vectors.…”

“…To estimate each CDS abundance, we mapped the trimmed reads to the extracted CDS using the RSEM tool. This resulted in an alignment of 39.5% of all reads; similar results were reported in previous sialome studies [ 37 , 39 , 40 ]. The remaining unmapped reads are potentially from the 5`and 3`UTR of the CDS, from non-coding RNA, or any sequence that failed to be extracted by not generating an ORF with at least 150 nucleotides, lacked a putative signal peptide, or failed to produce matches against previously deposited proteins.…”

“…The annotated CDS were used as a reference database for the proteomic part of the study resulting in the identification of unique peptides from 902 proteins (S2 File). As observed in other sialomes from blood-feeding arthropods [39][40][41], the "secreted" class was the most abundant functional class in both transcriptomic and proteomic relative quantifications (Table 1), with 519 CDS accounting for 45.5% of all TPM and 107 proteins representing 21.3% of all quantified protein in the salivary gland homogenate. The second most abundant functional group in our transcriptome was the "unknown" group (1,052 sequences representing 13.4% of all transcripts) which comprises novel CDS since they have low or no sequence identity to previously deposited sequences, while the second most abundant functional class in our proteomic analysis was the "protein modification" class with 92 proteins accounting for 12.7% of all identified proteins.…”

The discovery, distribution, and diversity of DNA viruses associated withDrosophila melanogasterin Europe

“…1 ). Drosophila Linvill Road densovirus is most closely related to the unclassified Haemotobia irritans densovirus ( Ribeiro et al 2019 ) and appears to encode at least three proteins, all in the same orientation ( Figs 1 and 2B ). As with Drosophila Esparto nudivirus, Kapun et al (2020) were unable to assemble the Drosophila Linvill Road densovirus genome from the DrosEU 2014 data and instead based their assembly on a collection of D.simulans from Linvilla, Pennsylvania, USA (SRR2396966; Machado et al 2019 ).…”

Chemosensory-Related Gene Family Members of the Horn Fly, Haematobia irritans irritans (Diptera: Muscidae), Identified by Transcriptome Analysis

“…While effective, insecticide resistance development in horn flies is well documented [ 2 ] and use of management practices to minimize the impact of fly resistant populations on pastured cattle has been challenging [ 3 , 4 ]. A need for pest management tools in organic livestock production settings and a desire to reduce the ecological impact of broad spectrum insecticides have increased interest in the development of nonchemical control strategies, including the potential for a vaccine targeting horn flies [ 5 , 6 ] and mechanical approaches for the removal of flies from bovine hosts [ 7 ]. Encouraging results have also been obtained using natural compounds to manipulate horn fly behavior.…”