Tsetse fly microbiota: form and function

Abstract

Tsetse flies are the primary vectors of African trypanosomes, which cause Human and Animal African trypanosomiasis in 36 countries in sub-Saharan Africa. These flies have also established symbiotic associations with bacterial and viral microorganisms. Laboratory-reared tsetse flies harbor up to four vertically transmitted organisms—obligate Wigglesworthia, commensal Sodalis, parasitic Wolbachia and Salivary Gland Hypertrophy Virus (SGHV). Field-captured tsetse can harbor these symbionts as well as environmentally acquired commensal bacteria. This microbial community influences several aspects of tsetse's physiology, including nutrition, fecundity and vector competence. This review provides a detailed description of tsetse's microbiome, and describes the physiology underlying host-microbe, and microbe-microbe, interactions that occur in this fly.

Adult blood-feeding tsetse flies, trypanosomes, microbiota and the fluctuating environment in sub-Saharan Africa

“…Impacts of the tsetse fly microbiome and nutrition on fly physiology and Trypanosoma transmission Tsetse flies harbor three bacterial symbionts, including the obligate primary (essential) symbiont Wigglesworthia glossinidia (Wang et al, 2013a) and the secondary (non-essential) symbiont Sodalis glossinidius (Dale and Maudlin, 1999). Both symbionts, which belong to the Enterobacteriaceae family, colonize the tsetse fly gut and are vertically transmitted to the intrauterine-developing larvae via milk gland secretions (Wang et al, 2013a).…”

“…Both symbionts, which belong to the Enterobacteriaceae family, colonize the tsetse fly gut and are vertically transmitted to the intrauterine-developing larvae via milk gland secretions (Wang et al, 2013a). Wigglesworthia encodes vitamins that may promote host reproduction as well as fly nutrition throughout its development (Nogge, 1982;Rio et al, 2012).…”

“…In addition to the midgut, Sodalis develops in several other tsetse fly (Glossina spp.) organs (Wang et al, 2013a). The specific elimination of Sodalis has been reported to result in reduced tsetse fly longevity (Dale and Welburn, 2001;Wang et al, 2013b).…”

“…These in turn depend on a variety of biotic and abiotic factors including: climate change; geographical distribution and environmental conditions of HAT foci; tsetse fly population flow between foci; disease epidemiology; type and distribution of trypanosome reservoirs; changes in tsetse fly nutritional behavior; and finally the nature and diversity of fly intestinal microbiota, including symbiotic (Wigglesworthia glossinidia, Sodalis glossinidius and Wolbacchia spp.) and diverse non-symbiotic bacteria (Dale and Maudlin, 1999;Wang et al, 2013a). Investigations of these factors have already begun in the past several years.…”

A novel intracellular mutualistic bacterium in the invasive antCardiocondyla obscurior

“…Some bacterial symbionts provide novel ecological traits to their insect hosts, for example, defense against pathogens or parasitoids (Oliver et al, 2003;Kaltenpoth et al, 2005), enhanced stress tolerance (Russell and Moran, 2006) or nutrients (Douglas, 2009). Nutrient-providing symbionts are commonly found in hosts with restricted diets, for example, aphids feeding on phloem sap (Baumann, 2005), blood-feeding diptera (Wang et al, 2013) or grain weevils (Heddi et al, 1999). Symbionts can provide essential amino acids, vitamins or help in nitrogen recycling (Nakabachi et al, 2005;Feldhaar et al, 2007;Michalkova et al, 2014;Patino-Navarrete et al, 2014).…”