Analysis of the transcriptome of adult Dictyocaulus filaria and comparison with Dictyocaulus viviparus, with a focus on molecules involved in host–parasite interactions

Abstract

Parasitic nematodes cause diseases of major economic importance in animals. Key representatives are species of Dictyocaulus (= lungworms), which cause bronchitis (= dictyocaulosis, commonly known as “husk”) and have a major adverse impact on the health of livestock. In spite of their economic importance, very little is known about the immunomolecular biology of these parasites. Here, we conducted a comprehensive investigation of the adult transcriptome of Dictyocaulus filaria of small ruminants and compared it with that of Dictyocaulus viviparus of bovids. We then identified a subset of highly transcribed molecules inferred to be linked to host-parasite interactions, including cathepsin B peptidases, fatty-acid and/or retinol-binding proteins, β-galactoside-binding galectins, secreted protein 6 precursors, macrophage migration inhibitory factors, glutathione peroxidases, a transthyretin-like protein and a type 2-like cystatin. We then studied homologs of D. filaria type 2-like cystatin encoded in D. viviparus and 24 other nematodes representing seven distinct taxonomic orders, with a particular focus on their proposed role in immunomodulation and/or metabolism. Taken together, the present study provides new insights into nematode-host interactions. The findings lay the foundation for future experimental studies and could have implications for designing new interventions against lungworms and other parasitic nematodes. The future characterization of the genomes of Dictyocaulus spp. should underpin these endeavors.

The Haemonchus contortus kinome - a resource for fundamental molecular investigations and drug discovery

“…Furthermore, we employed Pfam, PANTHER and SUPERFAMILY annotations using InterProScan v.5.7–48.0 to describe kinases that did not have a C. elegans homolog. We used the program EMBOSS Needle v.6.3.1 [ 33 ] to determine pairwise global amino acid sequence identities, similarities and the ratio of aligned positions versus gaps between H. contortus kinases and their closest homologs (based on PSI-BLAST) in C. elegans (KinBase) [ 44 ], sheep (KEGG) [ 45 ], Dictyocaulus filaria [ 46 ] and Teladorsagia circumcincta (WormBase ParaSite; PRJNA72569; WBPS3) [ 47 ]. …”

Perusal of parasitic nematode ‘omics in the post-genomic era

“…Inside the host, they penetrate the intestinal wall and migrate to the lymph nodes where they complete two molts, then travel through the lymphatic system to the heart and eventually the lungs [12]. D. filaria (ruminants) and D. viviparus (bovine) express multiple transcripts encoding proteins such as secreted chymotrypsin-like proteases, SCP/TAPS proteins, and others that may be involved in host-parasite interactions [98, 99]. In D. viviparus free-living stages, transcripts encoding proteins involved in the regulation of transcription, GPCR and steroid hormone-mediated signaling, and the transport of ions and oxygen are over-represented.…”