# Blood feeding-induced transcriptomic changes in the hard tick Ixodes persulcatus

## TL;DR

This study explores how the hard tick Ixodes persulcatus changes its gene activity during blood feeding, focusing on stress management and metabolism.

## Contribution

The study provides a new reference transcriptome and identifies species-specific gene expansions related to blood feeding in Ixodes persulcatus.

## Key findings

- A reference transcriptome with 56,900 unigenes was assembled for Ixodes persulcatus.
- Species-specific expansions in cytochrome P450s and glutathione S-transferases were identified.
- Transcriptional changes during blood feeding were linked to metabolism, stress response, and reproduction.

## Abstract

Ticks are hematophagous ectoparasites that must overcome significant physiological challenges during blood feeding. These include managing oxidative stress, detoxifying host-derived molecules, and reallocating energy to support digestion, tissue remodeling, and reproduction.

In this study, we conducted a de novo transcriptome assembly and genome-wide transcriptional profiling of female Ixodes persulcatus ticks at three key feeding stages: unfed, semi-engorged, and fully engorged. Functional annotation and Gene Ontology (GO) enrichment analyses were conducted to characterize stage-associated transcriptional changes, with a focus on metabolic detoxification and antioxidant systems.

We generated a reference transcriptome containing 56,900 unigenes. Comprehensive analyses of metabolic detoxification and antioxidant systems revealed species-specific expansions in key supergene families such as cytochrome P450s and glutathione S-transferases. The expression profiles across feeding stages revealed pronounced physiological changes in response to blood meal, and GO enrichment analysis showed that these changes were mainly involved in blood acquisition, nutrient metabolism, respiratory processes, hormone synthesis, egg development, immune responses, ROS detoxification, transcription and translation. These findings offer new insights into the molecular physiology of tick hematophagy and provide a valuable resource for future studies on stress responses and metabolic regulation in ticks.