Date Published: December 11, 2014
Publisher: Public Library of Science
Author(s): Wei Pan, Yujuan Shen, Xiuming Han, Ying Wang, Hua Liu, Yanyan Jiang, Yumei Zhang, Yanjuan Wang, Yuxin Xu, Jianping Cao, Malcolm K. Jones. http://doi.org/10.1371/journal.pntd.0003392
Abstract: BackgroundCystic hydatid disease (CHD) is caused by the larval stages of the cestode and affects humans and domestic animals worldwide. Protoscoleces (PSCs) are one component of the larval stages that can interact with both definitive and intermediate hosts. Previous genomic and transcriptomic data have provided an overall snapshot of the genomics of the growth and development of this parasite. However, our understanding of how PSCs subvert the immune response of hosts and maintains metabolic adaptation remains unclear. In this study, we used Roche 454 sequencing technology and in silico secretome analysis to explore the transcriptome profiles of the PSCs from E. granulosus and elucidate the potential functions of the excretory-secretory proteins (ESPs) released by the parasite.Methodology/Principal FindingsA large number of nonredundant sequences as unigenes were generated (26,514), of which 22,910 (86.4%) were mapped to the newly published E. granulosus genome and 17,705 (66.8%) were distributed within the coding sequence (CDS) regions. Of the 2,280 ESPs predicted from the transcriptome, 138 ESPs were inferred to be involved in the metabolism of carbohydrates, while 124 ESPs were inferred to be involved in the metabolism of protein. Eleven ESPs were identified as intracellular enzymes that regulate glycolysis/gluconeogenesis (GL/GN) pathways, while a further 44 antigenic proteins, 25 molecular chaperones and four proteases were highly represented. Many proteins were also found to be significantly enriched in development-related signaling pathways, such as the TGF-β receptor pathways and insulin pathways.Conclusions/SignificanceThis study provides valuable information on the metabolic adaptation of parasites to their hosts that can be used to aid the development of novel intervention targets for hydatid treatment and control.
Partial Text: Cystic hydatid disease (CHD) is a serious parasitic zoonosis that is caused by the larval stages of Echinococcus granulosus, a cestode that poses a threat to public health as well as significant economic losses , , . At present, more than 3 million people are infected with this parasite , , and the prevalence reaches 10% in some areas , . The disease is difficult to control because appropriate diagnostic procedures are lacking and the available drugs are inefficient .