Host Differentially Expressed Genes During Association With Its Defensive Endosymbiont

Mutualism, a beneficial relationship between two species, often requires intimate interaction between the host and symbiont to establish and maintain the partnership. The colonial marine bryozoan Bugula neritina harbors an as yet uncultured endosymbiont, “Candidatus Endobugula sertula,” throughout its life stages. The bacterial symbiont is the putative source of bioactive complex polyketide metabolites, the bryostatins, which chemically defend B. neritina larvae from predation. Despite the presence of “Ca. Endobugula sertula” in all life stages of the host, deterrent bryostatins appear to be concentrated in reproductive portions of the host colony, suggesting an interaction between the two partners to coordinate production and distribution of the metabolites within the colony. In this study, we identified host genes that were differentially expressed in control colonies and in colonies cured of the symbiont. Genes that code for products similar to glycosyl hydrolase family 9 and family 20 proteins, actin,...