Sugar transporters are essential for the long-distance carbon allocation in plants and contribute to both biotic and abiotic stress responses yet the molecular mechanisms of substrate specificity and conformational cycling are only beginning to emerge. Recent structural and biophysical studies of the Sugar Transport Protein, the Sucrose Carrier, and the Sugar Will Eventually be Exported Transporter families have revealed how both conserved and divergent features shape substrate recognition and conformational cycling. Despite these advances, complete transport cycles and native substrate-bound states remain unresolved for several transporters. Advancing our understanding will require integrating structural, dynamic, and functional insights to define the mechanisms that govern sugar transport which could enable future engineering of transport proteins relevant for plant resilience and productivity.
Clowes et al. (Wed,) studied this question.