Novel Insights Into The Transcriptome Of Dirofilaria Immitis

Background:The heartworm Dirofilaria immitis is the causal agent of cardiopulmonary dirofilariosis in dogs and cats, and also infects a wide range of wild mammals as well as humans. One bottleneck for the design of fundamentally new intervention and management strategies against D. immitis may be the currently limited knowledge of fundamental molecular aspects of D. immitis. Methodology/Principal Findings:A next-generation sequencing platform and powerful De novo short-read assembly, as well as detailed bioinformatic analysis were employed to assess a global view of the heartworm transcriptome. A total of20,810unigenes (mean length＝1,270bp) were assembled from22.3million clean reads. From these,15,698coding sequences (CDS) were inferred, and about85%of the unigenes had orthologs/homologs in public databases. Based on the transcriptome data, we propose five interesting research aspects for further investigation. Two groups of D. immitis molecules involved in host immune-system and human cardiovascular diseases may play an important role in parasite-host interactions and heart pathogenicity, respectively. Furthermore, we conducted a comprehensive comparative transcriptomic study to uncover4,157filarial-specific genes as well as3,795genes potentially involved in filarial-Wolbachia symbiosis. In addition, the potential intestine transcriptome of D. immitis (1,101genes) was mined for the first time, which might help to discover’hidden antigens’. Conclusions/Significance:This study provides novel insights into the transcriptome of D. immitis and sheds light on its molecular processes and survival mechanisms. It also provides a platform to discover new vaccine candidates and potential targets for new drugs against dirofilariosis. This work will also assist in efforts to decode the whole genome of D. immitis.