ABSTRACT: Analysis of expressed sequence tags from a significant livestock pest, the stable fly (Stomoxys calcitrans), identifies transcripts with a putative role in chemosensation and sex-determination
Project description:In insects, male accessory gland proteins (ACPs) are important reproductive proteins secreted by male accessory glands (MAGs) of the internal male reproductive system. During mating, ACPs were transferred along with sperms inside female bodies and have a significant impact on the physiology of female reproduction. Under sexual selection pressures, the ACPs exhibit remarkably rapid and divergent evolution and varies from species to species. The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is a major insect pest of cruciferous vegetables worldwide. The reproductive physiology on post-mating state of this species is still largely unknown, which is important for management of this pest. In this study, the ACPs transferred into females during mating were identified by using a tandem mass tags quantitative proteomic analysis. The MAGs were compared before and after mating immediately. In total, we identified 123 putative secreted ACPs, including most important physiological: regulators of proteolysis, transporters and protein export machinery, signal transduction and immunity. Comparing P. xylostella with other four insect ACPs, trypsins were the only ACPs detected in all insect species. This was the first time to identify and analyze ACPs in P. xylostella. Our results have provided an important list of putative secreted ACPs, and have set the stage for further explore functions of these putative proteins in P. xylostella reproduction.
Project description:Parasitoid wasps of the species Diachasmimorpha longicaudata are associated with a heritable poxvirus, known as DlEPV, that is stored in the venom gland of adult female wasps and transferred to tephritid fly hosts of the wasps during oviposition. We conducted a RNA-seq differential expression analysis to gain insight on how DlEPV can replicate in both wasps and their fly hosts but only cause pathogenic effects during replication in flies. Our analysis revealed that 91.2% (176 of 193) of DlEPV genes showed significant differential expression during peak virus replication in wasp venom glands compared to parasitized flies. Over 80% of DlEPV replication genes were significantly upregulated in wasps, while 79% of DlEPV putative virulence genes were significantly upregulated in fly hosts. These data therefore support a dichotomy of viral function, where virus replication is promoted in wasp tissue and virulence in host tissue. Such a division of viral activity could represent an important adaptation to maintain a stable symbiosis between this virus and its associated parasitoid.