Claudia Pogoreutz

Assessing the symbiotic interplay of photosynthesis and osmoregulation in Cnidaria

My current main project investigates the role of osmoregulation in cnidarian-algae-bacteria interactions. Osmoregulation is an essential mechanism to maintain cellular homeostasis in constantly changing environments. Photosymbiotic holobionts such as Cnidaria are characterized by the abundant symbiotic exchange of nutrients. Such symbiotic exchange includes osmotically active substances that are rapidly distributed throughout the holobiont, creating dynamic osmotic scenarios that require a coordination of osmoregulation among its members to achieve osmotic balance. Understanding the dynamics of holobiont osmoregulation may therefore be critical to understanding the metabolic regulation of symbiotic interactions.

Disentangling the uptake, synthesis, and translocation of highly soluble osmolytes across symbiotic partners has proven challenging. To tackle this challenging goal, I will harness the recent development of a new CryoNanoSIMS platform to visualize and quantify the subcellular distribution of key osmolytes in the intact cnidarian holobiont. Thereby, I seek to assess mechanisms of osmoregulation via osmolyte dynamics between cnidarian host and associated microbes in response to changing osmotic environments in the model system Exaiptasia diaphana. My research will help elucidate the interplay of holobiont nutrient cycling and osmoregulation as a metabolic pacemaker of symbiotic interactions.