Project summary
Tsetse flies (Diptera: Glossinidae) are the cyclical vectors of African trypanosomes (Trypanosoma
brucei spp.) which are the causative agents of fatal Human African Trypanosomiasis (HAT), and Animal
African Trypanosomiasis (AAT) in wild and domesticated animals. The taxonomically simple tsetse
enteric microbiota is dominated by an obligate bacterial mutualist, Wigglesworthia. A monoculture of
intracellular Wigglesworthia is found within a specialized organ, known as the bacteriome, located at the
anterior midgut. Several critical roles towards tsetse biology, spanning from essential nutrient
provisioning to immunological priming, have been characterized for Wigglesworthia. Importantly, the
elimination (or functional disruption) of the tsetse- Wigglesworthia association results in lags to tsetse
development and sizeable reductions in reproductive output. Our long-term objective is to expand our
understanding of the molecular mechanisms that coordinate tsetse-Wigglesworthia activity. Here, the
role of tsetse-generated microRNAs (miRNAs) towards facilitating the metabolic and developmental
integration of Wigglesworthia-tsetse symbiosis will be examined. Our research design involves the
identification of miRNAs that are differentially expressed within bacteriomes (relative to non-symbiont
harboring organs) during tsetse sex-specific development and pregnancy using deep sequencing-based
approaches. Additionally, the gene targets of these miRNAs will be initially identified using
computational genomics. The effect(s) of disrupting miRNA-275, significantly upregulated within the
bacteriomes of pregnant tsetse, towards tsetse fly life history traits, bacteriome integrity and
Wigglesworthia density will be characterized. This project aims to unravel fundamental molecular
mechanisms that coordinate host-microbiota biology. The disruption of pivotal Wigglesworthia-mediated
metabolic processes within tsetse offers novel targets for biocontrol.