A candidate transporter allowing symbiotic dinoflagellates to feed their coral hosts

Abstract

The symbiotic partnership between corals and dinoflagellate algae is crucial to coral reefs. Corals provide their algal symbionts with shelter, carbon dioxide and nitrogen. In exchange, the symbiotic algae supply their animal hosts with fixed carbon in the form of glucose. But how glucose is transferred from the algal symbiont to the animal host is unknown. We reasoned that a transporter resident in the dinoflagellate cell membrane would facilitate outward transfer of glucose to the surrounding host animal tissue. We identified a candidate transporter in the cnidarian symbiont dinoflagellate Breviolum minutum that belongs to the ubiquitous family of facilitative sugar uniporters known as SWE..