DSSS - The unique physiology of calcifying phytoplankton

Coccolithophores, unicellular photosynthetic protists, are responsible for the bulk of marine calcification, which is a major component of the long-term global carbon cycle. They are unique amongst other calcifying organisms in that they produce intricate crystalline calcite scales (coccoliths) in an intracellular compartment. These are secreted to the cell surface where they interlock to form a protective layer (the coccosphere). Intracellular calcification requires exceptional trans-cellular fluxes of calcium, inorganic carbon and protons, raising important questions about the transporters and pathways involved and for understanding cellular ion homeostasis more generally. In this presentation I will describe some recent advances in characterizing components of the calcification processes with a particular focus on plasma membrane and endomembrane transport, with implications for marine calcification in a changing ocean.