Genomics of worms, with an emphasis on Opisthorchis viverrini — opportunities for fundamental discovery and biomedical outcomes

Abstract

Neglected tropical diseases cause substantial morbidity and mortality in animals and people globally. Opisthorchiasis is one such disease, caused by the carcinogenic, Asian liver fluke, Opisthorchis viverrini. This hepatobiliary disease is known to be associated with malignant cancer (cholangiocarcinoma, CCA) and affects millions of people in Asia, including Thailand, Lao People's Democratic Republic (PDR) and Cambodia. No vaccine is available, and only one drug (praziquantel) is routinely employed against the parasite. Relatively little is known about the molecular biology of the fluke itself and the disease complex that it causes in humans. With the advent of high-throughput nucleic acid sequencing and bioinformatic technologies, it has now become possible to gain global insights into the molecular biology of parasites. The purpose of this minireview is (i) to discuss recent progress on the genomics of parasitic worms, with an emphasis on the draft genome and transcriptome of O. viverrini; (ii) to use results from an integrated, global analysis of the genomic and transcriptomic data, to explain how we believe that this carcinogenic fluke establishes in the biliary system, how it feeds, survives and protects itself in such a hostile, microaerobic environment within the liver, and to propose how this parasite evades or modulates host attack; and (iii) to indicate some of the challenges, and, more importantly, the exciting opportunities that the 'omic resources for O. viverrini now provide for a plethora of fundamental and applied research areas. Looking ahead, we hope that this genomic resource stimulates vibrant and productive collaborations within a consortium context, focused on the effective control of opisthorchiasis.

In silico prediction of secretory proteins of Opisthorchis viverrini, Clonorchis sinensis and Fasciola hepatica that target the host cell nucleus

“…Eukaryotic RNA polymerases are highly conserved and have identical substrates. Therefore a competitive mechanism between the parasites' and human's TFIIB-type domain-containing protein may lead to abnormal transcription (Papatpremsiri et al, 2015;Gasser et al, 2017). Given that the polypeptide A0A075AJD9 had no homologs in F. hepatica and it was predicted to be secretory and nuclear J o u r n a l P r e -p r o o f targeted, we hypothesize that such protein may be involved in the carcinogenic mechanism displayed by O. viverrini.…”

Human gnathostomiasis: a neglected food-borne zoonosis

“…Deciphering the genomes of Gnathostoma and their transcription will assist investigations into the immunobiology of this genus, as well as provide a genetic basis for the epidemiological study of these parasites. This will also facilitate studies on the biology, biochemistry, and physiology of these parasites, and the molecular mechanisms involved in their ability to modulate or evade the host immune system [124][125][126]. MicroRNAs have been assessed for their diagnostic value in several nematode infections [127][128][129], and the identification of specific biomarkers for the diagnosis of gnathostomiasis is a promising direction for future investigations.…”

The Curious Case of Cholangiocarcinoma: Opportunities for Environmental Health Scientists to Learn about a Complex Disease

“…Studying CCA will yield greater understanding of this process. The availability of the parasite's genome offers an opportunity for researchers to explore differences in infection rates among populations and the underlying causes, which can also inform comparative studies of understudied diseases [ 19 , 38 ].…”