Research article

A transcriptomic analysis of the adult stage of the bovine lungworm, Dictyocaulus viviparus

Shoba Ranganathan^{* 1,2} , Shivashankar H Nagaraj^{* 1} , Min Hu³ , Christina Strube⁴ , Thomas Schnieder⁴ and Robin B Gasser³

¹Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, New South Wales 2109, Australia

²Biotechnology Research Institute, Macquarie University, Sydney, New South Wales 2109, Australia

³Department of Veterinary Science, The University of Melbourne, 250 Princes Highway, Werribee, Victoria 3030, Australia

⁴Institute for Parasitology, University of Veterinary Medicine Hannover, Buenteweg 17, D-30559 Hannover, Germany

author email corresponding author email* Contributed equally

BMC Genomics 2007, 8:311doi:10.1186/1471-2164-8-311

Published:	5 September 2007

Abstract

Background

Lungworms of the genus Dictyocaulus (family Dictyocaulidae) are parasitic nematodes of major economic importance. They cause pathological effects and clinical disease in various ruminant hosts, particularly in young animals. Dictyocaulus viviparus, called the bovine lungworm, is a major pathogen of cattle, with severe infections being fatal. In this study, we provide first insights into the transcriptome of the adult stage of D. viviparus through the analysis of expressed sequence tags (ESTs).

Results

Using our EST analysis pipeline, we estimate that the present dataset of 4436 ESTs is derived from 2258 genes based on cluster and comparative genomic analyses of the ESTs. Of the 2258 representative ESTs, 1159 (51.3%) had homologues in the free-living nematode C. elegans, 1174 (51.9%) in parasitic nematodes, 827 (36.6%) in organisms other than nematodes, and 863 (38%) had no significant match to any sequence in the current databases. Of the C. elegans homologues, 569 had observed 'non-wildtype' RNAi phenotypes, including embryonic lethality, maternal sterility, sterility in progeny, larval arrest and slow growth. We could functionally classify 776 (35%) sequences using the Gene Ontologies (GO) and established pathway associations to 696 (31%) sequences in Kyoto Encyclopedia of Genes and Genomes (KEGG). In addition, we predicted 85 secreted proteins which could represent potential candidates for developing novel anthelmintics or vaccines.

Conclusion

The bioinformatic analyses of ESTs data for D. viviparus has elucidated sets of relatively conserved and potentially novel genes. The genes discovered in this study should assist research toward a better understanding of the basic molecular biology of D. viviparus, which could lead, in the longer term, to novel intervention strategies. The characterization of the D. viviparus transcriptome also provides a foundation for whole genome sequence analysis and future comparative transcriptomic analyses.