9UDW | pdb_00009udw

Cryo-EM structure of the human G6P transporter SLC37A2 in the G6P bound state with a symmetric cytosolic-open conformation.

• PDB DOI: https://doi.org/10.2210/pdb9UDW/pdb
• EM Map EMD-64073: EMDB EMDataResource

• Classification: MEMBRANE PROTEIN
• Organism(s): Homo sapiens
• Expression System: Homo sapiens
• Mutation(s): No 


• Deposited: 2025-04-07 Released: 2025-11-05 
• Deposition Author(s): Sun, L., Liu, X., Lai, Q.
• Funding Organization(s): National Natural Science Foundation of China (NSFC)

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 3.50 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

Structural basis of glucose-6-phosphate transport by human SLC37A2.

Lai, Q., Xu, M., Gao, Y., Yang, Z., Sun, L., Liu, X.

(2026) Nat Struct Mol Biol 33: 112-122

• PubMed: 41225050 
• DOI: https://doi.org/10.1038/s41594-025-01712-4
• Primary Citation Related Structures: 
  9UCM, 9UDV, 9UDW, 9UDX


• PubMed Abstract: 
  

  Glucose-6-phosphate (G6P) transporters are crucial for glucose metabolism by mediating G6P transport from the cytoplasm to endoplasmic reticulum (ER). However, their transport mechanisms remain poorly understood. Here, we elucidate the structural and functional basis of human solute carrier family 37 member 2 (SLC37A2), a G6P transporter implicated in metabolic regulation and macrophage inflammation. We show that SLC37A2 functions as a uniporter, facilitating G6P transport independent of inorganic phosphate gradients. Structures of SLC37A2 in the apo and G6P-bound states reveal a dimeric architecture. Both the ER luminal-open and cytosolic-open structures are captured, showing the structural dynamics during G6P transport. G6P is coordinated by SLC37A2 through interactions with its phosphate and hydroxyl groups. Furthermore, mapping mutations associated with glycogen storage disease type Ib onto SLC37A2 highlights residues essential for transport activity. Together, this work provides structural insights into G6P transport and establishes a framework for understanding related metabolic disorders.

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Organizational Affiliation: 
• Department of Neurology, The First Affiliated Hospital of USTC, MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.
Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, China.
Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei, China.
Department of Neurology, The First Affiliated Hospital of USTC, MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China. [e-mail].
Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, China. [e-mail].
Department of Neurology, The First Affiliated Hospital of USTC, MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China. [e-mail].
Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, China. [e-mail].
Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei, China. [e-mail].
Department of Neurology, The First Affiliated Hospital of USTC, MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China. [e-mail].
Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, China. [e-mail].
Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei, China. [e-mail].

Biological Assembly 1  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: electron microscopy

Macromolecule Content 

• Total Structure Weight: 109.47 kDa 
• Atom Count: 6,987 
• Modeled Residue Count: 904 
• Deposited Residue Count: 1,002 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Glucose-6-phosphate exchanger SLC37A2	A, B	501	Homo sapiens	Mutation(s): 0  Gene Names: SLC37A2
UniProt & NIH Common Fund Data Resources
Find proteins for Q8TED4 (Homo sapiens) Explore Q8TED4  Go to UniProtKB:  Q8TED4
PHAROS:  Q8TED4 GTEx:  ENSG00000134955

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
G6P (Subject of Investigation/LOI)	C [auth A], D [auth B]	6-O-phosphono-alpha-D-glucopyranose C6 H13 O9 P NBSCHQHZLSJFNQ-DVKNGEFBSA-N

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 3.50 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

EM Software:

Task	Software Package	Version
MODEL REFINEMENT	PHENIX	1.13_2998:
RECONSTRUCTION	cryoSPARC	v4.2.1

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2025-11-05 
Deposition Author(s): Sun, L., Liu, X., Lai, Q.

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Funding Organization	Location	Grant Number
National Natural Science Foundation of China (NSFC)	China	32471279
National Natural Science Foundation of China (NSFC)	China	32322041
National Natural Science Foundation of China (NSFC)	China	32321001
National Natural Science Foundation of China (NSFC)	China	W2412029

Revision History  

• Version 1.0: 2025-11-05
  Type: Initial release
  
• Version 1.1: 2026-05-27
  Changes: Data collection, Database references