Screening and analysis of Hc-ubq and Hc-gst related to desiccation survival of infective Haemonchus contortus larvae

- DDRT-PCR screened differentially expressed genes in H. contortus L3s upon desiccation.
- Hc-ubq and Hc-gst had the highest identity percentage in bioinformatic analysis.
- RNAi revealed important roles of Hc-ubq and Hc-gst in nematode desiccation tolerance.

Infective Haemonchus contortus larvae (L3s) are able to protect themselves from desiccation. To explore the molecular mechanisms of desiccation survival, mRNA differential display RT-PCR was used to screen differentially expressed genes in L3s upon desiccation, followed by RNAi experiments to define gene functions. In this, 58 differentially expressed transcripts were obtained. Among these, the BF-U01A and CH-U02A fragments represent genes with the highest identity percentage in bioinformatic analysis. They were named Hc-ubq and Hc-gst based on their respective homologous ubiquitin in Caenorhabditis elegans and glutathione S-transferase in H. contortus. Quantitive RT-PCR results indicated that they were both up-regulated in desiccated L3s. Hc-ubq and Hc-gst RNAi in H. contortus showed reduced survival rate of L3s, with unchanged locomotion behavior. Homologous Ce-ubq-2 and Ce-gst-7 RNAi in C. elegans also displayed higher larval death rate. These results suggest that ubq and gst may play important roles in nematode desiccation tolerance. Our study analyzed desiccation resistance related genes in H. contortus L3s, and revealed significant research implications on the mechanisms behind nematode desiccation survival.