MicroRNA profiling of the intestinal tissue of Kazakh sheep after experimental Echinococcus granulosus infection, using a high-throughput approach.

Song Jiang,Wenqiao Hui,Qian Ban,Xuhai Wang,Xin Li,Bin Jia

doi:10.1051/parasite/2016023

Abstract

Cystic echinococcosis (CE), caused by infection with the larval stage of the cestode Echinococcus granulosus, is a chronic zoonosis, to which sheep are highly susceptible. Previously, we found that Kazakh sheep with different MHC haplotypes differed in CE infection. Sheep with haplotype MHCMvaIbc-SacIIab-Hin1Iab were resistant to CE infection, while their counterparts without this haplotype were not. MicroRNAs (miRNAs), a class of small non-coding RNAs, are key regulators of gene expression at the post-transcriptional level and play essential roles in fundamental biological processes such as development and metabolism. To identify microRNA controlling resistance to CE in the early stage of infection, microRNA profiling was conducted in the intestinal tissue of sheep with resistant and non-resistant MHC haplotypes after peroral infection with E. granulosus eggs. A total of 351 known and 186 novel miRNAs were detected in the resistant group, against 353 known and 129 novel miRNAs in the non-resistant group. Among these miRNAs, 83 known miRNAs were significantly differentially expressed, including 75 up-regulated and 8 down-regulated miRNAs. Among these known microRNAs, miR-21-3p, miR-542-5p, miR-671, miR-134-5p, miR-26b, and miR-27a showed a significantly higher expression in CE-resistant sheep compared to the CE-non-resistant library, with the FC > 3. Functional analysis showed that they were NF-kB pathway-responsive miRNAs, which are involved in the inflammation process. The results suggest that these microRNAs may play important roles in the response of intestinal tissue to E. granulosus.

Highlights

Cystic echinococcosis (CE) is a chronic parasitic zoonosis caused by infection with the larval stage of the cestode Echinococcus granulosus, resulting in the development of cysts in human and domestic animals
As technological advancements have resulted in increased discovery of new miRNAs, in the present study, using RNA deep sequencing technology, we found a large number of new miRNAs in studied Kazakh sheep
These new miRNAs were all confirmed as having a hairpin secondary structure in their predicted precursor sequences

Summary

Introduction

Cystic echinococcosis (CE) is a chronic parasitic zoonosis caused by infection with the larval stage of the cestode Echinococcus granulosus, resulting in the development of cysts in human and domestic animals. Especially in sheep, which appear to be highly susceptible to infection, CE causes considerable health problems and thereby significantly affects the income of herdsmen. It has been demonstrated that the pathogenesis of CE is strongly influenced by genetics, and certain MHC polymorphisms are associated with individual susceptibility in humans [1, 2]. We have carried out several studies to investigate the relationship between MHC-DRB1/DQB1 gene polymorphism and genetic resistance or susceptibility to CE in Chinese Merino, Duolang, and Kazakh sheep [9, 16, 22, 23]. CE-resistant sheep have an increased genetic capability to respond to and subsequently reject parasites when challenged

Methods

Results

Conclusion