Differential Gene Expression in Bugula Neritina during Symbiotic Association with "Candidatus Endobugula Sertula"

The colonial marine bryozoan, Bugula neritina, harbors an uncultured endosymbiont, “Candidatus Endobugula sertula” throughout its life stages. The bacterial symbiont has been proposed to be a source of complex polyketide metabolites, the bryostatins, that chemically defend B. neritina larvae from predation. Within a bryozoan colony, significantly higher amounts of bryostatins are found in ovicell-bearing zooids where the developing larvae are brooded, as compared to ovicell-free zooids. It is hypothesized that signaling between B. neritina and “Ca. Endobugula sertula” may be involved in the regulation of bryostatin production in different zooids, as well as in maintenance of the symbiosis. In this study, suppression subtractive hybridization (SSH) was used to identify differentially expressed host genes during this association. The identified genes suggest that the host plays a role in the distribution and localization of bacterial symbionts in different host zooids, possibly to regulate levels of bryostatin production in the zooids. INDEX WORDS: Symbiosis, Bugula neritina, Bryostatins, Differential gene expression DIFFERENTIAL GENE EXPRESSION IN BUGULA NERITINA DURING SYMBIOTIC ASSOCIATION WITH “CANDIDATUS ENDOBUGULA SERTULA”