Main Pathways and Ion Channels Differentially Expressed in the Transcriptome of Male and Female Adult Angiostrongylus can-tonensis using a Deep Sequencing Approach

Background: The adult stage is an important period in the life cycle of Angiostrongylus cantonensis, as it is at this stage that male and female worms produce thousands of fertilized eggs daily. Methods: To explore the transcriptional details of adult male and female A. cantonensis, three groups of male and female adult worms were collected, and their transcriptome profiles were analyzed using an Illumina next-generation sequencing platform. A total of 283,910,174 clean reads were obtained, and 137,626 unigenes and 237,059 transcripts were then generated. Unigenes were successfully annotated by querying the Gene Ontology (GO), the Kyoto Encyclopedia of Genes and Genomes (KEGG), NCBI non-redundant protein sequences (NR), PFAM, STRING, and SWISS-PROT databases. Then, differentially expressed genes (DEGs) between the 2 genders were identified. The GO and KEGG databases were used for DEG annotation, and a number of DEG annotations were enriched. Results: The results obtained from querying DEGs using the GO and KEGG databases revealed that male and female adult worms exhibited differences in metabolism and production. Protein phosphorylation, ion transport, and calcium transport were all significantly enriched according to GO annotation. A number of other pathways were also enriched according to KEGG enrichment annotation, including the pentose phosphate pathway, nitrogen metabolism, oocyte meiosis pathway, neuroactive ligand-receptor interaction, calcium signaling pathway, transforming growth factor β (TGF-β) signaling pathway etc. Conclusion: We hypothesized that the nervous system of the worm plays a key role in the physiological regulation of adult A. cantonensis, and based on this, the function of the calcium-signaling pathway should be investigated.