Genetic innovations in animal-microbe symbioses

The evolutionary persistence of animal symbioses depends on both host and symbiont innovations. Perreau and Moran review how genome sequencing and related experiments have clarified how these innovations arise under different symbiont population structures, categorized here as open, closed and mixed. Animal hosts have initiated myriad symbiotic associations with microorganisms and often have maintained these symbioses for millions of years, spanning drastic changes in ecological conditions and lifestyles. The establishment and persistence of these relationships require genetic innovations on the parts of both symbionts and hosts. The nature of symbiont innovations depends on their genetic population structure, categorized here as open, closed or mixed. These categories reflect modes of inter-host transmission that result in distinct genomic features, or genomic syndromes, in symbionts. Although less studied, hosts also innovate in order to preserve and control symbiotic partnerships. New capabilities to sequence host-associated microbial communities and to experimentally manipulate both hosts and symbionts are providing unprecedented insights into how genetic innovations arise under different symbiont population structures and how these innovations function to support symbiotic relationships.

Automated summary

The evolutionary persistence of animal symbioses relies on innovations from both hosts and symbionts, reflected in genetic changes. Through genome sequencing and experiments, we can understand how innovations arise under different symbiont population structures and how these innovations function to support symbiotic relationships.