Structures of human SGLT in the occluded state reveal conformational changes during sugar transport.

ABSTRACT: Sodium-Glucose Cotransporters (SGLT) mediate the uphill uptake of extracellular sugars and play fundamental roles in sugar metabolism. Although their structures in inward-open and outward-open conformations are emerging from structural studies, the trajectory of how SGLTs transit from the outward-facing to the inward-facing conformation remains unknown. Here, we present the cryo-EM structures of human SGLT1 and SGLT2 in the substrate-bound state. Both structures show an occluded conformation, with not only the extracellular gate but also the intracellular gate tightly sealed. The sugar substrate are caged inside a cavity surrounded by TM1, TM2, TM3, TM6, TM7, and TM10. Further structural analysis reveals the conformational changes associated with the binding and release of substrates. Thes

SUBMITTER: Cui W 

PROVIDER: S-EPMC10203128 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature