Comparison of transcriptomes of viruliferous and nonviruliferous, tobacco thrips, Frankliniella fusca (Hinds)

Thrips transmitted Tomato spotted wilt virus (TSWV) (genus Tospovirus, family Bunyaviridae) is a serious pathogen of agricultural and horticultural crops worldwide. Thrips transmit TSWV in a persistent propagative manner, and acquisition of TSWV is stage specific. TSWV is also known to affect thrips biology and behavior. However, TSWV-induced changes in thrips at genetic and molecular levels are largely unknown. Thus, we adopted transcriptomics approach to investigate these changes in viruliferous and non-viruliferous tobacco thrips, Frankliniella fusca [Hinds] at larval, pupal, and adult stages. Transcriptomics involves the study of RNA molecules that are present in a given organism at a specific period. We developed thrips transcriptomes and identified a total of 795 differentially expressed transcripts. Functional annotations of the transcripts were performed using Gene Ontology databases. Transcripts associated with virus entry and replication were upregulated in viruliferous thrips. Transcripts pertaining to five immune pathways viz., apoptosis, phagocytosis, proteolysis, toll, and RNAi were upregulated in viruliferous adults. Further, in viruliferous adults, transcripts associated with reproduction, embryo development, and cell differentiation were upregulated several folds, suggesting positive influence of TSWV infection on thrips’ reproduction. In case of non-viruliferous larvae, transcripts involved with multicellular organismal development including cell growth, neuron differentiation, and cell division were upregulated indicating that TSWV infection also could negatively influence thrips development. Transcripts identified in this study could be exploited to develop transgenic plants for thrips and TSWV management. For example, genes important for thrips development or for the virus infection cycle could be targeted.