Tracing horizontal Wolbachia movements among bees (Anthophila): a combined approach using multilocus sequence typing data and host phylogeny

Abstract

The endosymbiotic bacterium Wolbachia enhances its spread via vertical transmission by generating reproductive effects in its hosts, most notably cytoplasmic incompatibility (CI). Additionally, frequent interspecific horizontal transfer is evident from a lack of phylogenetic congruence between Wolbachia and its hosts. The mechanisms of this lateral transfer are largely unclear. To identify potential pathways of Wolbachia movements, we performed multilocus sequence typing of Wolbachia strains from bees (Anthophila). Using a host phylogeny and ecological data, we tested various models of horizontal endosymbiont transmission. In general, Wolbachia strains seem to be randomly distributed among bee hosts. Kleptoparasite-host associations among bees as well as other ecological links could not be supported as sole basis for the spread of Wolbachia. However, cophylogenetic analyses and divergence time estimations suggest that Wolbachia may persist within a host lineage over considerable timescales and that strictly vertical transmission and subsequent random loss of infections across lineages may have had a greater impact on Wolbachia strain distribution than previously estimated. Although general conclusions about Wolbachia movements among arthropod hosts cannot be made, we present a framework by which precise assumptions about shared evolutionary histories of Wolbachia and a host taxon can be modelled and tested.

The hitchhiker's guide to Europe: the infection dynamics of an ongoingWolbachiainvasion and mitochondrial selective sweep inRhagoletis cerasi

“…; Gerth et al . ) and rarely observed in real time in the field (Schuler et al . ), it does not necessarily lead to a successful establishment in new populations.…”

Prevalence and diversity of Wolbachia bacteria infecting insect pests of stored products

“…Kyei-Poku et al (2005) reported similarities among wsp isolates suggestive of horizontal transfer among species of lice (Anoplura, Mallophaga) that are neither predators nor have any known parasitoids. Gerth et al (2013) compared the diversity of Wolbachia infections associated with bees (Hymenoptera) that shared either a taxonomic affinity or an ecological association, and concluded that the latter was insufficient to explain observed patterns. Phylogenetic interpretations are confounded with use of wsp sequences, because the gene is prone to recombination (Baldo et al, 2005).…”

“…Similar difficulties have been reported by others. Examples include the failure to obtain complete sets of MLST sequences for Wolbachia isolates from a weevil (Coleoptera: Curculionidae), species of aphids (Hemiptera) (Augustinos et al, 2011) and from species of bees (Hymenoptera) (Gerth et al, 2013). As concluded by Augustinos et al (2011), further work is needed to improve detection and characterization of Wolbachia isolates across diverse host taxa.…”

Plant–mediated horizontal transmission of Wolbachia between whiteflies

“…There is growing evidence for common horizontal transmission of Wolbachia from one species to another (Ahmed et al , 2013; Gerth et al , 2013; Brown and Lloyd, 2015), and the transmission route is becoming a hotspot of research, given its importance in ecological and evolutionary biology (Vavre et al , 1999; Sintupachee et al , 2006; Caspi-Fluger et al , 2012; Gehrer and Vorburger, 2012). Recently, Wolbachia horizontal transmission through invertebrate predators and parasitoids has been revealed (Huigens et al , 2000, 2004; Le Clec'h et al , 2013; Ahmed et al , 2015).…”