English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Background  Ticks are blood-sucking arthropods and a primary function of tick salivary proteins is to counteract the host’s immune response. Tick salivary Kunitz-domain proteins perform multiple functions within the feeding lesion and have been classified as venoms; thereby, constituting them as one of the important elements in the  arms race  with the host. The two main mechanisms advocated to explain the functional heterogeneity of tick salivary Kunitz-domain proteins are gene sharing and gene duplication. Both do not, however, elucidate the evolution of the Kunitz family in ticks from a structural dynamic point of view. The Red Queen hypothesis offers a fruitful theoretical framework to give a dynamic explanation for host-parasite interactions. Using the recent salivary gland  Ixodes ricinus  transcriptome we analyze, for the first time, single Kunitz-domain encoding transcripts by means of computational, structural bioinformatics and phylogenetic approaches to improve our understanding of the structural evolution of this important multigenic protein family.    Results  Organizing the  I. ricinus  single Kunitz-domain peptides based on their cysteine motif allowed us to specify a putative target and to relate this target specificity to Illumina transcript reads during tick feeding. We observe that several of these Kunitz peptide groups vary in their translated amino acid sequence, secondary structure, antigenicity, and intrinsic disorder, and that the majority of these groups are subject to a purifying (negative) selection. We finalize by describing the evolution and emergence of these Kunitz peptides. The overall interpretation of our analyses discloses a rapidly emerging Kunitz group with a distinct disulfide bond pattern from the  I. ricinus  salivary gland transcriptome.    Conclusions  We propose a model to explain the structural and functional evolution of tick salivary Kunitz peptides that we call  target-oriented evolution . Our study reveals that combining analytical approaches (transcriptomes, computational, bioinformatics and phylogenetics) improves our understanding of the biological functions of important salivary gland mediators during tick feeding.

Understanding the evolutionary structural variability and target specificity of tick salivary Kunitz peptides using next generation transcriptome data