Phylogenetic evidence for horizontal transmission of Wolbachia in host- parasitoid associations

Abstract

Endosymbiotic Wolbachia infect a number of arthropod species in which they can affect the reproductive system. While maternally transmitted, unlike mitochondria their molecular phylogeny does not parallel that of their hosts. This strongly suggests horizontal transmission among species, the mechanisms of which remain unknown. Such transfers require intimate between-species relationships, and thus host-parasite associations are outstandingly appropriate for study. Here, we demonstrate that hymenopteran parasitoids of frugivorous Drosophila species are especially susceptible to Wolbachia infection. Of the five common European species, four proved to be infected; furthermore, multiple infections are common, with one species being doubly infected and two triply infected (first report). Phylogenetic statuses of the Wolbachia infecting the different species of the community have been studied using the gene wsp, a highly variable gene recently described. This study reveals exciting similarities between the Wolbachia variants found in parasitoids and their hosts. These arguments strongly support the hypothesis of frequent natural Wolbachia transfers into other species and open a new field for genetic exchanges among species, especially in host-parasitoid associations.

Intra-Individual Coexistence of a Wolbachia Strain Required for Host Oogenesis With Two Strains Inducing Cytoplasmic Incompatibility in the Wasp Asobara Tabida

“…Consistent with a previous study (Vavre et al 1999a), all individuals were coinfected by the three Wolbachia strains wAtab1, wAtab2, and wAtab3. Nine of the 46 triply infected females (19.1%) produced no progeny, whereas all of the remaining 37 females were fertile and produced an average (Ϯ SD) of 106.2 (Ϯ 20.0) offspring.…”

“…Specific polymerase chain reaction (PCR) assays were used to detect the three Wolbachia strains previously described in A. tabida (Vavre et al 1999a). Based on the Wolbachia wsp gene sequences of the three strains (Genbank accession number AF124856, AF124857, AF124859), specific primers were designed for each of them: 5Ј-TGG TAT TAC AAA TGT AGC-3Ј for wAtab1, 5Ј-ACC TAT AAG AAA GAC AAG-3Ј for wAtab2 (172F in Zhou et al 1998), and 5Ј-AAA GGG GAC TGA TGA TGT-3Ј for wAtab3.…”

“…It has been shown that all A. tabida wasps from a single line simultaneously harbor three different Wolbachia strains, all of which belong to the A clade of Wolbachia (Vavre et al 1999a). Intra-individual multiple infections have already been described in several Wolbachia-infected species (for an overview, see Mouton et al 2003), and typically are characteristic of Wolbachia strains that induce cytoplasmic incompatibility (CI).…”

Cloning and sequencing of wsp encoding gene fragments reveals a diversity of co-infecting Wolbachia strains in Acromyrmex leafcutter ants

“…Sequences generated in this study are indicated in bold. The bar represents a distance of 0.050 (about 25 MY if a wsp evolutionary rate of 0.2% per MY is assumed, Wenseleers et al, 2001). and Solignac, 1995;Wenseleers et al, 1998;Werren et al, 1995a, b;Werren and Windsor, 2000) or more rarely, triple infections (Kondo et al, 2002;Vavre et al, 1999). A stable triple Wolbachia infection has also been created artificially by microinjection of an additional strain in double infected Drosophila (Rousset et al, 1999).…”

Tracing the history and ecological context of Wolbachia double infection in a specialist host (Urophora cardui)—parasitoid (Eurytoma serratulae) system

“…Facultative associations are prone to turnover, and this may channel interspecific exchange. For Wolbachia specifically, incongruent cophylogenies with hosts (Shoemaker et al., 2002; Vavre, Fleury, Lepetit, Fouillet, & Bouletreau, 1999), the observation that phylogenetically diverse taxa share identical or similar Wolbachia strains (Huigens, de Almeida, Boons, Luck, & Stouthamer, 2004; Noda et al., 2001) and recombination between strains (Bordenstein, Wernegreen, & Werren, 2006; Werren & Bartos, 2001) indicate that interspecific transmissions of Wolbachia are common on an evolutionary time scale (Ahmed, Breinholt, & Kawahara, 2016; Baldo et al., 2008; O'Neill, Giordano, Colbert, Karr, & Robertson, 1992; Russell, Latorre, Sabater‐Muñoz, Moya, & Moran, 2003). Yet the number of studies documenting interspecific transmission or spread of strains in natural populations remains few (e.g., Hoshizaki & Shimada, 1995; Kriesner, Hoffmann, Lee, Turelli, & Weeks, 2013; Schuler et al., 2013; Turelli & Hoffmann, 1991).…”