Molecular characterization of hard tick Haemaphysalis longicornis from China by sequences of the internal transcribed spacers of ribosomal DNA

Zhong-Bo Li,Guo-Hua Liu,Tian-Yin Cheng

doi:10.1007/s10493-018-0210-x

Abstract

In the present study, the entire first and second internal transcribed spacer (ITS-1 and ITS-2) regions of nuclear ribosomal DNA (rDNA) of Haemaphysalis longicornis from China were amplified by polymerase chain reaction. The 45 representative amplicons were sequenced, and sequence variation in the ITS was examined. The ITS sequences of H. longicornis were 3644 bp in size, including the part of 18S rDNA, 28S rDNA sequences and the complete ITS-1, 5.8S rDNA and ITS-2 sequences. Sequence analysis revealed that the ITS-1, 5.8S rDNA and ITS-2 of this hard tick were 1582, 152, and 1610 bp in size, respectively. The intra-specific sequence variations of ITS-1 and ITS-2 within H. longicornis were 0–2 and 0–2.2%; however, the inter-specific sequence differences among members of the genus Haemaphysalis were significantly higher, being 35.1–55.2 and 37–52% for ITS-1 and ITS-2, respectively. The molecular approach employed in this study provides the foundation for further studies of the genetic variation of H. longicornis from different hosts and geographical origins in China.

Highlights

Tick are obligate hematophagous ectoparasites, which usually carry a number of pathogenic microorganisms and parasites, causing diseases in animals and humans (Hajdušek et al 2013)
The complete internal transcribed spacers (ITS) regions including primer flanking 18S ribosomal DNA (rDNA), ITS-1, 5.8S rDNA, ITS-2 and 28S rDNA sequences was amplified by polymerase chain reaction (PCR) from individual tick DNA preparations using two primers, namely ITS1F (5′-TCATAAGCTCGCGTTGATT-3′), ITS1R (5′-AGCTGGCTGCGTTCTTCAT-3′), ITS2F (5′-CGAGACTTGGTGTGAATTGCA-3′) and ITS2R (5′-TCCCATACACCA-CATTTCCCG-3′) (Chitimia et al 2009)
A total of genomic DNA was isolated from 45 adult female H. longicornis, which collected from wild hedgehogs and goats in Henan, Hunan and Shandong provinces, China

Summary

Introduction

Tick are obligate hematophagous ectoparasites, which usually carry a number of pathogenic microorganisms and parasites, causing diseases in animals and humans (Hajdušek et al 2013). Ticks belong to three families: Ixodidae, Argasidae and Nuttalliellidae (Burger et al 2012). Among these three families, the Ixodidae is the most important, and. Many studies have confirmed that the Ixodidae can transmit a variety of pathogens, including bacteria, helminths, protozoa, and viruses (Greay et al 2016; Silaghi et al 2016). Haemaphysalis longicornis (Acari: Ixodidae) has a wide distribution in different countries and regions around the world, including China, India, Japan, Vietnam and the far east region of Russia. Haemaphysalis longicornis possess a variety of hosts, including sheep, goat, cattle, horse, cat and chickens (Wang et al 2015)

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