Screening Of Genes Related To Albendazole Resistance Of Haemonchus Contortus And Study On Its Molecular Regulation

Haemonchus contortus is one of the major parasites of ruminant digestive systems,which has caused huge economic losses to the breeding industry.Due to long-term drug deworming,Haemonchus contortus has developed resistance to common anthelmintic drugs such as albendazole in many areas,which has become an important factor restricting the prevention and control of parasitic diseases.So far,the mechanism of parasite resistance has not been fully understood.In this study,epidemiological investigation and drug resistance test of Haemonchus contortus in Wushenqi sheep and Chayouhouqi sheep from Inner Mongolia were carried out.Comparative transcriptome analysis were launched on pre-and post-dose,albendazole-susceptible and resistant strains of Haemonchus contortus.Functional,metabolic pathways and possible drug resistance mechanisms of possible drug resistance genes were analyzed,and three drug-resistant genes were screened for recombinant expression,providing a foundation for exploring the molecular mechanism of resistance to Haemonchus contortus,screening for molecular markers of drug resistance detection and the establishment of early differential diagnosis methods for drug resistance.The main findings wereas follows:(1)The average infection rates of Haemonchus contortus in Wushenqi sheep and Chayouhouqi sheep were 89%and 78%,and the reduction rates of eggs were 9.80%and 20.4%,respectively.The Haemonchus contortus in these two regions is resistant to albendazole.(2)Between the pre-and post-dose transcriptome analysis of Haemonchus contortus,a total of 851 differential expressed genes were obtained,which were significantly enriched in ATP binding,metabolic processes,proteolysis and other functional classifications.Participation in ribosome synthesis,apoptosis,peroxisome proliferator-activated receptor(PPAR)and other pathways.(3)In the comparative transcriptomics analysis of sensitive and resistant strains of Haemonchus contortus,913 significant differential expressed genes were obtained,mainly involved in glutathione metabolism,metabolism of cytochrome P450 to xenobiotics,drug metabolism cytochrome P450 and so on.(4)Cloning and bioinformatics analysis of three drug resistance genes were performed,three recombinant expression systems of BL21(pETGST),BL21(pETP450)and BL21(pETABC)were successfully constructed,and purified recombinant proteins were obtained by Ni+.