Lutzomyia longipalpis, a disease vector case review: Can simultaneous metatranscriptomic and transcriptomic analyses aid its control?

*CHRISTINA B. MCCARTHY; LORENA G. CALIGIURI; SORAYA A. ACARDI; MA. SOLEDAD SANTINI; OSCAR D. SALOMÓN; GASTÓN ROZADILLA; JORGELINA MOREIRAS CLEMENTE; NAGILA F. C. SECUNDINO

Yosemite

Conferencia; 48th Annual Conference of the Society for Vector Ecology; 2018

Society for Vector Ecology

Lutzomyia longipalpis is a sand fly found from Mexico to Argentina, and is the main vector inthe New World of Leishmania infantum (syn. chagasi), which is thecausal agent of visceral leishmaniasis. Leishmaniasis is a vector-borneneglected infectious disease of worldwide incidence that causes ≈500,000 new casesand more than 59,000 deaths each year. Gut microbiota play important roles inthe growth and development of insects, and metatranscriptomic analyses ofinsect hosts enable the assessment of metabolically active components in themicrobiome. Furthermore, transcriptomic analyses of insects in their naturalenvironments are invaluable to identify genes as targets for pest control. Weused unbiased high-throughput pyrosequencing technology to compare themetatranscriptomes and transcriptomes of wild male and female L. longipalpisfrom Posadas (Argentina) and Lapinha Cave (Brazil). Sequences frombacteria, fungi, protists, plants, and metazoans were identified in themetatranscriptomes. In particular, agregarine that parasitises L. longipalpis was found in male specimens from Posadas. Thetranscriptomes showed characteristic profiles correlating with the environmentof origin and with the associated taxa, among which there were various putativetargets for control via RNAinterference. These studies provided the basis for analysing the significance of thebiocontrol candidates found for this vector. In particular, themetatranscriptomic analysis enabled the development of a PCR-based assay forthe detection and identification of natural gregarine infections in L.longipalpis. On the other hand, sand fly transcripts were used to designprimers for dsRNA assays, and bioassays are currently underway to evaluate theireffectiveness to control L. longipalpisusing remote delivery systems. In summary, these comprehensive analyses have contributeda unique insight into the biology of these vectors and the development of novelbioinsecticides for their control.