The Holobiont Imperative: Perspectives from Early Emerging Animals

Speaker: Professor Thomas Bosch, Kiel University

Host: Professor Karsten Kristiansen

Abstract
Most epithelia in animals are colonized by microbial communities. These resident microbes influence fitness and thus ecologically important traits of their hosts, ultimately forming a holobiont consisting of a multicellular host and a community of associated microorganisms. Here, I evaluate information in understanding the evolution of epithelial-based innate immunity provided by Hydra, an apparently simple animal which shares deep evolutionary connections with all animals including humans. I highlight growing evidence that a mutual intertwinement between the stem cell regulatory machinery of the host and the resident microbiota composition ensures the maintenance of homeostasis between animals and their resident microbiota. Results from this work have opened up new avenues of studies, including insights into how developmental pathways interact with environmental cues such as microbes.