Response of Leucine-Rich Repeat Domain-Containing Protein in Haemaphysalis longicornis to Babesia microti Infection and Its Ligand Identification
- 16 April 2021
- journal article
- research article
- Published by American Society for Microbiology in Infection and Immunity
- Vol. 89 (5)
- https://doi.org/10.1128/iai.00268-20
Abstract
Haemaphysalis longicornis is a blood-feeding hard tick known for transmitting a variety of pathogens, including Babesia. How the parasites in the imbibed blood become anchored in the midgut of ticks is still unknown. Leucine-rich repeat domain (LRR)-containing protein, which is associated with the innate immune reaction and conserved in many species, has been detected in H. longicornis and has previously been indicated in inhibiting the growth of Babesia gibsoni. However, the detailed mechanism is unknown. In this study, one of the ligands for LRR from H. longicornis (HlLRR) was identified in B. microti, designated as BmActin (Babesia microti actin), using GST pull-down experiments and immunofluorescence assay. Moreover, RNA interference of HlLRR led to a decrease in the BmActin mRNA expression in the midgut of fully engorged ticks, which fed on B. microti-infected mice. We also found that the expression level of the innate immune molecules in H. longicornis, defensin, antimicrobial peptides (AMPs), and lysozyme were downregulated after the knockdown of HlLRR. However, subolesin expression was upregulated. These results indicate that HlLRR not only recognizes BmActin but may also modulate innate immunity in ticks to influence Babesia growth, which will further benefit the development of anti-Babesia vaccines or drugs.Keywords
Funding Information
- National key research and development program (2017YFC1200202)
- National key research and development program (2017YFC1200204)
This publication has 49 references indexed in Scilit:
- The Ecology, Genetic Diversity, and Phylogeny of Huaiyangshan Virus in ChinaJournal of Virology, 2012
- The First Human Case of Rickettsia tamurae Infection in JapanCase Reports in Dermatology, 2011
- Mosquito immune defenses against Plasmodium infectionDevelopmental & Comparative Immunology, 2010
- Babesia and its hosts: adaptation to long-lasting interactions as a way to achieve efficient transmissionVeterinary Research, 2009
- A Cysteine Protease Is Critical for Babesia spp. Transmission in Haemaphysalis TicksPLoS Pathogens, 2008
- Babesial Vector Tick Defensin againstBabesiasp. ParasitesInfection and Immunity, 2007
- Cell-Surface Actin Binds Plasminogen and Modulates Neurotransmitter Release from Catecholaminergic CellsJournal of Neuroscience, 2006
- Developmentally Essential Protein Flightless I Is a Nuclear Receptor Coactivator with Actin Binding ActivityMolecular and Cellular Biology, 2004
- Structural principles of leucine‐rich repeat (LRR) proteinsProteins, 2003
- The immune response of DrosophilaNature, 2003