Sugar transporters for intercellular exchange and nutrition of pathogens.
Sugar efflux transporters are essential for the maintenance of animal blood glucose levels, plant nectar production, and plant seed and pollen development. Despite broad biological importance, the identity of sugar efflux transporters has remained elusive. Using optical glucose sensors, we identified a new class of sugar transporters, named SWEETs, and show that at least six out of seventeen Arabidopsis, two out of over twenty rice and two out of seven homologues in Caenorhabditis elegans, and the single copy human protein, mediate glucose transport. Arabidopsis SWEET8 is essential for pollen viability, and the rice homologues SWEET11 and SWEET14 are specifically exploited by bacterial pathogens for virulence by means of direct binding of a bacterial effector to the SWEET promoter. Bacterial symbionts and fungal and bacterial pathogens induce the expression of different SWEET genes, indicating that the sugar efflux function of SWEET transporters is probably targeted by pathogens and symbionts for nutritional gain. The metazoan homologues may be involved in sugar efflux from intestinal, liver, epididymis and mammary cells.
PubMed ID: 21107422
PMC ID: PMC3000469
Article link: Nature.
Grant support: 1R01DK079109 NIDDK NIH HHS , F32GM083439-02 NIGMS NIH HHS , ZR01GM06886-06A1 NIGMS NIH HHS , R01 DK079109-01 NIDDK NIH HHS , R01 DK079109-02 NIDDK NIH HHS , R01 DK079109-03 NIDDK NIH HHS , R01 DK079109-03S1 NIDDK NIH HHS , R01 DK079109-04 NIDDK NIH HHS , R01 GM068886 NIGMS NIH HHS , R01 DK079109 NIDDK NIH HHS