title: De novo assembly and annotation of the salivary gland transcriptome of Rhipicephalus appendiculatus male and female ticks during blood feeding.
abstract: Tick secretory proteins modulate haemostasis, inflammation and immune responses of the host and are attractive recombinant anti-tick vaccine candidates. Yet, many of the proteins have not been characterised due to the limited sequence availability for ticks and other arthropods for homology-based annotation. To address this limitation, we sequenced the salivary glands of the economically important adult male and female Rhipicephalus appendiculatus ticks during feeding. The quality-filtered Illumina sequencing reads were de novo assembled to generate a R. appendiculatus sialotranscriptome of 21,410 transcripts. A non-redundant set of 12,761 R. appendiculatus proteins was predicted from the transcripts, including 2134 putative secretory and 8237 putative housekeeping proteins. Secretory proteins accounted for most of the expression in the salivary gland transcriptome (63%). Of the secretory protein class, the Glycine-rich superfamily contributed 66% and the Lipocalin family 12% of the transcriptome expression. Differential expression analysis identified 1758 female and 2346 male up-regulated transcripts, suggesting varying blood-feeding mechanisms employed between female and male ticks. The sialotranscriptome assembled in this work, greatly improves on the sequence information available for R. appendiculatus and is a valuable resource for potential future vaccine candidate selection.
authors.affiliation: Parasites, Vectors and Vector-borne Diseases, Onderstepoort Veterinary Institute, Agricultural Research Council, Onderstepoort, South Africa; Biotechnology Platform, Agricultural Research Council, Onderstepoort, South Africa; College of Agriculture and Environmental Sciences, University of South Africa, Johannesburg, South Africa.
authors.forename: Minique H
authors.initials: MH
authors.lastname: de Castro
authors.affiliation: Parasites, Vectors and Vector-borne Diseases, Onderstepoort Veterinary Institute, Agricultural Research Council, Onderstepoort, South Africa.
authors.forename: Daniel
authors.initials: D
authors.lastname: de Klerk
authors.affiliation: Parasites, Vectors and Vector-borne Diseases, Onderstepoort Veterinary Institute, Agricultural Research Council, Onderstepoort, South Africa.
authors.forename: Ronel
authors.initials: R
authors.lastname: Pienaar
authors.affiliation: Parasites, Vectors and Vector-borne Diseases, Onderstepoort Veterinary Institute, Agricultural Research Council, Onderstepoort, South Africa; School of Life Sciences, University of KwaZulu-Natal, Durban, South Africa.
authors.forename: Abdalla A
authors.initials: AA
authors.lastname: Latif
authors.affiliation: Biotechnology Platform, Agricultural Research Council, Onderstepoort, South Africa; College of Agriculture and Environmental Sciences, University of South Africa, Johannesburg, South Africa.
authors.forename: D Jasper G
authors.initials: DJ
authors.lastname: Rees
authors.affiliation: Parasites, Vectors and Vector-borne Diseases, Onderstepoort Veterinary Institute, Agricultural Research Council, Onderstepoort, South Africa; College of Agriculture and Environmental Sciences, University of South Africa, Johannesburg, South Africa; Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Pretoria, South Africa. Electronic address: mansb@arc.agric.za.
authors.forename: Ben J
authors.initials: BJ
authors.lastname: Mans
mesh_terms: D000818:Animals; D001769:Blood / Q000378:metabolism*; D005260:Female; D020869:Gene Expression Profiling; D008297:Male; D058977:Molecular Sequence Annotation; D048494:Rhipicephalus / Q000502:physiology*; D012469:Salivary Glands / Q000502:physiology*; D017423:Sequence Analysis, RNA
keywords: De novo transcriptome assembly; Next generation sequencing; Rhipicephalus appendiculatus; Salivary glands; Secretory proteins; Sialotranscriptomics