9DXO | pdb_00009dxo

Cryo-EM structure of human OATP1C1 F240A mutant in complex with estrone 3-sulfate

• PDB DOI: https://doi.org/10.2210/pdb9DXO/pdb
• EM Map EMD-47293: EMDB EMDataResource

• Classification: TRANSPORT PROTEIN
• Organism(s): Homo sapiens
• Expression System: Homo sapiens
• Mutation(s): Yes 


• Deposited: 2024-10-11 Released: 2025-07-16 
• Deposition Author(s): Ge, Y., Yadav, G.P., Jiang, J., Huang, P.
• Funding Organization(s): National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 2.60 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

Structural insights into brain thyroid hormone transport via MCT8 and OATP1C1.

Ge, Y., Dou, T., Nguyen, T.U., Yadav, G.P., Wensel, T.G., Jiang, J., Huang, P.

(2025) Cell 

• PubMed: 40680733 
• DOI: https://doi.org/10.1016/j.cell.2025.06.032
• Primary Citation of Related Structures:  
  9DWY, 9DXO, 9DXP, 9MR5


• PubMed Abstract: 
  

  Adequate delivery of thyroid hormones to the brain is crucial for normal neurological development. MCT8 and OATP1C1, two solute carrier (SLC) transporters, mediate the passage of thyroid hormones across the blood-brain barrier and into the central nervous system. Mutations in MCT8 result in Allan-Herndon-Dudley syndrome (AHDS), an X-linked birth defect characterized by neurodevelopmental impairments and peripheral hyperthyroidism, whereas OATP1C1 deficiency is linked to brain hypometabolism and progressive neurodegeneration. Here, we report cryoelectron microscopy (cryo-EM) structures of MCT8 and OATP1C1 bound with the active thyroid hormone triiodothyronine (T3) and the prohormone thyroxine (T4) at 2.9 and 2.3 Å resolutions, respectively. Combined with functional studies, we elucidate their distinct thyroid hormone recognition and transport mechanisms and explain disease mutations. Although extracellular allosteric sites are not a common feature of SLC transporters, we identify one in OATP1C1. Collectively, these findings illuminate key aspects of thyroid hormone transport, a fundamental process in development and disease.

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Organizational Affiliation: 
• Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA.
Laboratory of Membrane Proteins and Structural Biology, Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
Laboratory for Biomolecular Structure and Dynamics (LBSD), Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA.
Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine, Houston, TX 77030, USA.
Laboratory of Membrane Proteins and Structural Biology, Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA. Electronic address: [e-mail].
Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA. Electronic address: [e-mail].

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: electron microscopy

Macromolecule Content 

• Total Structure Weight: 83.51 kDa 
• Atom Count: 4,276 
• Modeled Residue Count: 545 
• Deposited Residue Count: 746 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Solute carrier organic anion transporter family member 1C1	A	746	Homo sapiens	Mutation(s): 1  Gene Names: SLCO1C1, OATP14, OATP1C1, OATPF, SLC21A14
UniProt & NIH Common Fund Data Resources
Find proteins for Q9NYB5 (Homo sapiens) Explore Q9NYB5  Go to UniProtKB:  Q9NYB5
PHAROS:  Q9NYB5 GTEx:  ENSG00000139155

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
FY5 (Subject of Investigation/LOI)	B [auth A], C [auth A], D [auth A]	estrone 3-sulfate C18 H22 O5 S JKKFKPJIXZFSSB-OVWQWFNUSA-N

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 2.60 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

EM Software:

Task	Software Package	Version
MODEL REFINEMENT	PHENIX	1.20_4459:

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2025-07-16 
Deposition Author(s): Ge, Y., Yadav, G.P., Jiang, J., Huang, P.

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Funding Organization	Location	Grant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)	United States	R01GM150878

Revision History  

• Version 1.0: 2025-07-16
  Type: Initial release
  
• Version 1.1: 2025-07-30
  Changes: Data collection, Database references