Factors Limiting the Spread of the Protective Symbiont Hamiltonella defensa in Aphis craccivora Aphids

Factors limiting the spread of the protective symbiont Hamiltonella defensa in Aphis craccivora Aphids.

Many insects are associated with heritable symbionts that mediate ecological interactions, including host protection against natural enemies. The cowpea aphid, Aphis craccivora, is a polyphagous pest that harbors Hamiltonella defensa, which defends against parasitic wasps. Despite this protective benefit, this symbiont occurs only at intermediate frequencies in field populations. To identify fa...

Factors Limiting the Spread of the Protective Symbiont <em>Hamiltonella defensa</em> in <em>Aphis craccivora</em> Aphids

Culture-Facilitated Comparative Genomics of the Facultative Symbiont Hamiltonella defensa

Many insects host facultative, bacterial symbionts that confer conditional fitness benefits to their hosts. Hamiltonella defensa is a common facultative symbiont of aphids that provides protection against parasitoid wasps. Protection levels vary among strains of H. defensa that are also differentially infected by bacteriophages named APSEs. However, little is known about trait variation among s...

INVERTEBRATE MICROBIOLOGY Worldwide Populations of the Aphid Aphis craccivora Are Infected with Diverse Facultative Bacterial Symbionts

Facultative bacterial endosymbionts can play an important role in the evolutionary trajectory of their hosts. Aphids (Hemiptera: Aphididae) are infected with a wide variety of facultative endosymbionts that can confer ecologically relevant traits, which in turn may drive microevolutionary processes in a dynamic selective environment. However, relatively little is known about how symbiont divers...

Hamiltonella defensa, genome evolution of protective bacterial endosymbiont from pathogenic ancestors.

Eukaryotes engage in a multitude of beneficial and deleterious interactions with bacteria. Hamiltonella defensa, an endosymbiont of aphids and other sap-feeding insects, protects its aphid host from attack by parasitoid wasps. Thus H. defensa is only conditionally beneficial to hosts, unlike ancient nutritional symbionts, such as Buchnera, that are obligate. Similar to pathogenic bacteria, H. d...