Submitted to: Functional and Integrative Genomics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/5/2011
Publication Date: 12/28/2011
Citation: Li, R.W., Schroeder, S.G. 2011. Cytoskeleton remodling and alterations in smooth muscle contractility in the bovine jejunum during the early stage of Cooperia oncophora infection. Functional and Integrative Genomics. 12(1):35-44.
Interpretive Summary: Gastrointestinal nematodes of the genus Cooperia are important gastrointestinal nematodes infecting ruminants in the temperate regions of the world and are becoming the most prevalent parasites in cattle operations in United States and Western Europe, partially due to resistance of these species to anthelmintic drugs. In this study, we conducted an in-depth transcriptome analysis of the bovine jejunum in response to Cooperia oncophora experimental infection. We identified multiple signaling pathways significantly impacted during infection. Our results provided evidence that enhanced smooth muscle contractility in the bovine jejunum may represent an important aspect of host immune responses against a primary C. oncophora infection.
Technical Abstract: Gastrointestinal nematodes of the genus Cooperia are arguably the most important parasites of cattle. We characterized the bovine jejunal transcriptome in response to C. oncophora infection using RNA-seq technology. Approximately 71% of the 25,670 bovine genes were detected in the jejunal transcriptome. However, 16,552 genes were expressed in all samples tested, probably representing the core component of the transcriptome. 20 most abundant genes accounted for 12.7% of the sequences from the transcriptome. A 7-day infection seemingly induced a minor change in the transcriptome (162 genes). Additionally, a total of 162,412 intron-exon junctions were identified. Among them, 1,164 appeared unique to one of the 2 groups: 868 splicing junctions were observed only in infected animals while 278 were only present in all 4 control animals. Biological functions associated with muscle contraction were predominantly Gene Ontology terms enriched in the genes differentially expressed by infection. The primary function of 2 out of 4 regulatory networks impacted was related to skeletal and muscular systems. A total of 34 pathways were significantly impacted by infection. Several pathways were directly related to host immune responses, such as acute phase response, leukocyte extravasation, and antigen presentation, consistent with our previous findings. Calcium signaling and actin cytoskeleton signaling were among the pathways most significantly impacted by infection in the bovine jejunum. Together, our data suggest that smooth muscle hypercontractility may be initiated as a result of a primary C. oncophora infection, which may represent a mechanism for host responses in the jejunum during early infection.