Negotiations Between Early Evolving Animals and Symbionts
Cnidarians are constantly exposed to microbes. It is therefore not too surprising that molecular analyses have revealed a variety of molecular pathways used by cnidarians to respond to microbial exposure. When approaching the epithelium of a cnidarian, microbes first encounter extracellular germline-encoded surface receptors that recognize microbe-associated molecular patterns (MAMPs). Examples of MAMPs include lipopolysaccharides (LPSs), peptidoglycan (PGN), flagellin, and microbial nucleic acids. Perception of a MAMP at the cell surface is achieved by Toll-like receptors (TLRs) which then initiate MAMP-triggered immunity. In this chapter, we consider one by one the major components used by the cnidarians host to interact with the microbes.
KeywordsInnate Immune System Adaptive Immune System Beneficial Microbe Host Pathway Cnidarian Host
- Bosch TCG, Augustin R, Anton-Erxleben F, Fraune S, Hemmrich G, Zill H, Rosenstiel P, Jacobs G, Schreiber S, Leippe M, Stanisak M, Grotzinger J, Jung S, Podschun R, Bartels J, Harder J, Schroder JM (2009) Uncovering the evolutionary history of innate immunity: the simple metazoan Hydra uses epithelial cells for host defence. Dev Comp Immunol 33:559–569CrossRefPubMedGoogle Scholar