METHODS: The D. pteronyssinus genome was assembled by a hybrid assembly approach using PacBio, Illumina and Ion Torrent reads. Transcriptomes of D. pteronyssinus and D. farinae were compared using Cufflinks. Allergens were identified by two-dimensional gel electrophoresis and MALDI-ToF MS. Allergenicities of the novel allergens were detected by ELISA using patients’ sera against bacteria expressing recombinant proteins.
RESULTS: Genomic, transcriptomic, and proteomic approaches revealed full gene structures of 21 known allergens, and uncovered 11 putative allergen homologs. A high-quality D. pteronyssinus genome of 66.8 Mb was constructed. This genome assembly represented 98.2% of estimated genome size, with contig N50 being 80kb. The first comprehensive transcriptomic analysis of D. pteronyssinus and D. farinae revealed distinctively expressed allergen genes between the two dust mites, in which Der p 1, 5, 10, 21 and 24 were highly expressed in D. pteronyssinus, while Der f 10, 13, 21, 26 and 31 expressed higher in D. farinae. From ELISA, IgE binding rates of Der p 25, 26, 28, 32, and 33 were 38.5-65.3%, in which Der p 33 had the highest allergenicity.
CONCLUSIONS: Bioinformatics and experimental characterizations of D. pteronyssinus genome and allergens provide important resources for future investigation of HDM allergens.