Structures of human glucose-6-phosphate transporter reveal reciprocal antiport mechanism driving glucose-6-phosphate and inorganic phosphate exchange.

ABSTRACT: Glucose-6-phosphate transporter 1 (G6PT1) is essential for systemic glucose homeostasis, and its deficiency causes glycogen storage disease type 1b (GSD1b). G6PT1 functions as a sugar-phosphate/inorganic phosphate (Pi) antiporter, orchestrating G6P transport into the endoplasmic reticulum lumen driven by a Pi gradient. Despite its physiological significance, the molecular mechanisms underlying substrate recognition and antiport activity remain poorly characterized. Here, we present cryo-electron microscopy structures of human G6PT1 in apo, Pi-bound, and GlcN6P-bound (a G6P analogue) states, all captured in cytosol-open conformations. Combined with molecular docking and functional assays, these structures elucidate the molecular basis for Pi and G6P recognition in G6PT1. Comparative analysi

SUBMITTER: Wang Q 

PROVIDER: S-EPMC12748760 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature