Short-chain dehydrogenases in Haemonchus contortus: changes during life cycle and in relation to drug-resistance

AbstractShort-chain dehydrogenases/reductases (SDRs) regulate the activities of many hormones and other signaling molecules and participate in the deactivation of various carbonyl-bearing xenobiotics. Nevertheless, knowledge about these important enzymes in helminths remains limited. The aim of our study was to characterize the SDR superfamily in the parasitic nematodeHaemonchus contortus. Genome localization of SDRs was explored, and phylogenetic analysis in comparison with SDRs from free-living nematodeCaenorhabditis elegans and the domestic sheep (Ovis aries, a typical host ofH. contortus) was constructed. The expression profile of selected SDRs during the life cycle along with differences between the drug-susceptible and drug-resistant strains, were also studied. Genome sequencing enabled the identification of 46 members of the SDR family inH. contortus. A number of genes have no orthologue in the sheep genome. In all developmental stages ofH. contortus, SDR1, SDR3, SDR5, SDR6, SDR14, and SDR18 genes were the most expressed, although in individual stages, huge differences in expression levels were observed. A comparison of SDRs expression between the drug-susceptible and drug-resistant strains ofH. contortus revealed several SDRs with changed expression in the resistant strain. Specifically, SDR1, SDR12, SDR13, SDR16 are SDR candidates related to drug-resistance, as the expression of these SDRs is  consistently increased in most stages of the drug-resistantH. contortus. ...
Source: Veterinary Research - Category: Veterinary Research Source Type: research