Transcriptome analysis of the synganglion from the honey bee mite, Varroa destructor and RNAi knockdown of neural peptide targets. (March 2016)

• Record Type: Journal Article
• Authors: Campbell, Ewan M.; Budge, Giles E.; Watkins, Max; Bowman, Alan S.
• Is Part Of: Insect biochemistry and molecular biology. Volume 70(2016:Mar.)
• Page Start: 116
• Page End: 126
• Publication Date: 2016-03
• Subjects: Varroa destructor -- Apis mellifera -- Synganglion -- Deformed wing virus -- Allatostatin -- Crustacean hyperglycaemic hormone -- gene knockdown; Insect biochemistry -- Periodicals; Insects -- Physiology -- Periodicals; Insects -- Molecular aspects -- Periodicals; Biochemistry -- Periodicals; Insectes -- Biochimie -- Périodiques; Insectes -- Composition -- Périodiques; Insectes -- Physiologie -- Périodiques; Insectes -- Aspect moléculaire -- Périodiques; Biochimie -- Périodiques; Biochemistry; Insect biochemistry; Insects -- Molecular aspects; Insects -- Physiology; Periodicals; 572.8157
• DOI: 10.1016/j.ibmb.2015.12.007
• Languages: English
• ISSNs: 0965-1748

Abstract

Abstract: Varroa mites ( Varroa destructor ) and the viruses that they transmit are one of the major contributing factors to the global honey bee crisis. Gene products within the nervous system are the targets of all the insecticides currently used to control Varroa but there is a paucity of transcriptomic data available for Varroa neural tissues. A cDNA library from the synganglia ("brains") of adult female Varroa was constructed and 600 ESTs sequenced and analysed revealing several current and potential druggable targets. Contigs coding for the deformed wing virus (DWV) variants V. destructor virus-1 (VDV-1) and the recombinant (VDV-1DVD ) were present in the synganglion library. Negative-sense RNA-specific PCR indicated that VDV-1 replicates in the Varroa synganglion and all other tissues tested, but we could not detect DWV replicating in any Varroa tissue. Two neuropeptides were identified in the synganlion EST library: a B-type allatostatin and a member of the crustacean hyperglycaemic hormone (CHH) superfamily. Knockdown of the allatostatin or the CHH-like gene by double-stranded RNA-interference (dsRNAi) resulted in 85% and 55% mortality, respectively, of Varroa . Here, we present the first transcriptomic survey in Varroa and demonstrate that neural genes can be targeted by dsRNAi either for genetic validation of putative targets during drug discovery programmes or as a potential control measure in itself. Graphical abstract: Highlights: The first transcriptome of Varroa destructor . Deformed wing virus variant (VDV-1) present and replicating in Varroa synganglion ("brain"). B-type allatostatin ( Vd AST) and a crustacean hyperglycaemic hormone ( Vd CHH) identified in Varroa synganglia. Vd AST and Vd CCH expression knocked down by dsRNAi resulting in significant mortality.