Molecular mechanisms underlying calcification in coccolithophores

A numberof studies are providing increasing genomic and tran-scriptomic information on the molecular components of transport, and biochemical control in the cell biology of calcification in coccol-ithophores. In this review we summarise recent evidence for molecular components involved in the trans-cellular transport of Ca²⁺, inorganic carbon and H⁺ between the external medium and the in-tracellular calcification compartment. We present new hypotheses for the transport of infstrates to the site of calcification and for the removal of products, highlighting key gaps in our current knowledge. We also discuss how a cellular and molecular approach will improve abilities to understand and predict responses and adaptation to changing ocean chemistry of this important group of microorganisms.