Polyclonal symbiont populations in hydrothermal vent tubeworms and the environment
Author(s)Polzin, Julia; Arevalo, Philip Alexander; Nussbaumer, Thomas; Polz, Martin F; Bright, Monika
MetadataShow full item record
Horizontally transmitted symbioses usually house multiple and variable symbiont genotypes that are acquired from a much more diverse environmental pool via partner choice mechanisms. However, in the deep-sea hydrothermal vent tubeworm Riftia pachyptila (Vestimentifera, Siboglinidae), it has been suggested that the Candidatus Endoriftia persephone symbiont is monoclonal. Here, we show with high-coverage metagenomics that adult R. pachyptila house a polyclonal symbiont population consisting of one dominant and several low-frequency variants. This dominance of one genotype is confirmed by multilocus gene sequencing of amplified housekeeping genes in a broad range of host individuals where three out of four loci (atpA, uvrD and recA) revealed no genomic differences, while one locus (gyrB) was more diverse in adults than in juveniles. We also analysed a metagenome of free-living Endoriftia and found that the free-living population showed greater sequence variability than the host-associated population. Most juveniles and adults shared a specific dominant genotype, while other genotypes can dominate in few individuals. We suggest that although generally permissive, partner choice is selective enough to restrict uptake of some genotypes present in the environment.
DepartmentMassachusetts Institute of Technology. Department of Civil and Environmental Engineering
Proceedings of the Royal Society B: Biological Sciences
Polzin, Julia et al. "Polyclonal symbiont populations in hydrothermal vent tubeworms and the environment." Proceedings of the Royal Society B: Biological Sciences 286, 1896 (February 2019): 20181281. © 2019 The Author(s)
Final published version