Cloning and bioinformatics analysis of aquaporin proteins in the European house dust mite, Dermatophagoides pteronyssinus

Aquaporins are highly conserved water channel proteins involved in the transport of solutes across membranes. The few aquaporins identified to date play major roles in excretion in insects. Excretion is a major source of indoor allergens from the house dust mite species, but, to date, aquaporins have not been well studied in these species. We used RNA sequencing to study the transcriptome of the house dust mite Dermatophagoides pteronyssinus to identify putative aquaporin family members. RNA was isolated from more than 2000 mites for 5GREEK TONOS-RACE and 3GREEK TONOS-RACE. Putative aquaporins were identified through BLAST alignments, and primers were designed to amplify the five identified sequences. These cDNA fragments were then inserted into bacterial plasmids for molecular cloning and sequencing of DerpAQP1, DerpAQP2, DerpAQP3, DerpAQP4, and DerpAQP5 (GenBank accessions nos. KY305293, KY305294, KY305295, KY305296, and KY305298, respectively). Phylogenetic analysis of cloned sequences revealed the clustering of these putative aquaporins into two groups with human aquaporins (hAQPs): DerpAQP3 was clustered with hAQP8, hAQP11, and hAQP12; and DerpAQP1, DerpAQP2, DerpAQP4, DerpAQP5 were clustered with hAQP3, hAQP7 hAQP9, and hAQP10. This study provides a foundation for future studies of the importance of these proteins to dust mite functions and allergenicity.