Phylogenetic diversity of the intracellular symbiont Wolbachia in termites

摘要

The genus Wolbachia (class Alphaproteobacteria) encompasses obligately intracellular bacteria that are cytoplasmically transmitted in arthropods and filarial nematodes ([O’Neill et al., 1997], [Stouthamer et al., 1999] and [Werren, 1997]). They are found in greater than 20% of all insect species, numerous other arthropods, and filarial nematodes ([Bandi et al., 1998], [Jeyaprakash and Hoy, 2000] and [Werren et al., 1995]). Unlike most other obligately intracellular bacteria, Wolbachia form a monophyletic clade comprised of both mutualistic and parasitic lineages, that highlight the diversity of symbiotic associations. In arthropods, Wolbachia are commonly known as reproductive parasites, since they distort host reproductive strategies to selfishly enhance their maternal transmission into the next generation (Werren, 1997). Examples of the effects of Wolbachia infection include male-killing, feminization of genetic males, parthenogenesis, and cytoplasmic incompatibility. In contrast, the Wolbachia lineages infecting filarial nematodes are beneficial symbionts required for host fertility and larval viability (Bandi et al., 2001).