Related Experiment Video
Updated: Dec 20, 2025

Study of the Functions and Activities of Neuronal K-Cl Co-Transporter KCC2 Using Western Blotting
Published on: December 9, 2022
OATP1B3 Expression and Function is Modulated by Coexpression with OCT1, OATP1B1, and NTCP.
Yuchen Zhang1, Melissa Ruggiero1, Bruno Hagenbuch2
1Department of Pharmacology, Toxicology, and Therapeutics, The University of Kansas Medical Center, Kansas City, Kansas.
Organic anion transporting polypeptide (OATP) 1B3 interacts with other transporters like organic cation transporter (OCT) 1, affecting its expression and function. These interactions highlight potential over- or underestimations in drug-drug interaction studies using single transporter systems.
Area of Science:
- Hepatobiliary Transport
- Drug Metabolism
- Molecular Interactions
Background:
- Organic anion transporting polypeptide (OATP) 1B3 is a key drug transporter in human hepatocytes.
- OATP1B3 participates in the uptake of endogenous and exogenous substances.
- Previous studies showed OATP1B3 forms hetero-oligomers with OATP1B1 and Na+/taurocholate cotransporting polypeptide (NTCP).
Purpose of the Study:
- To investigate organic cation transporter (OCT) 1 as a potential interacting partner of OATP1B3.
- To determine the functional consequences of OATP1B3 hetero-oligomerization with OATP1B1, NTCP, and OCT1.
- To assess the impact of these interactions on OATP1B3 expression and transport activity.
Main Methods:
- Coimmunoprecipitation assays in human hepatocytes to detect OATP1B3 and OCT1 interactions.
- Proximity ligation assay to visualize OATP1B3 and OCT1 interactions in cells and liver sections.
- Measurement of OATP1B3 plasma membrane expression and cholecystokinin-8 (CCK-8) uptake in HEK293 cells under various coexpression conditions.
Main Results:
- OATP1B3 interacts with OCT1 in human hepatocytes and HEK293 cells.
- Coexpression with OCT1 decreased OATP1B3 plasma membrane expression, while OATP1B1 and NTCP increased it.
- OCT1 coexpression enhanced OATP1B3 turnover rate, whereas OATP1B1 and NTCP decreased it.
Conclusions:
- Hetero-oligomerization of OATP1B3 with OATP1B1, NTCP, and OCT1 significantly modifies its expression and function.
- Single transporter overexpression systems may over- or underestimate OATP1B3 function and drug-drug interactions in vivo.
- Protein-protein interactions play a crucial role in regulating transporter activity in hepatocytes.
More Related Videos
09:40Author Spotlight: Unveiling the Role of TMOD3 in Platinum Resistance and Immune Infiltration in Ovarian Cancer
Published on: August 2, 2024
13:16Characterization of Membrane Transporters by Heterologous Expression in E. coli and Production of Membrane Vesicles
Published on: December 31, 2019
Related Concept Videos
Carrier-Mediated Transport
Active transport involves two types of membrane-spanning transporters: uptake and efflux. Uptake transporters are expressed in the small...
The Significance of Membrane Transport
Transporters facilitate either an active or passive movement of solutes. They can allow a single-molecule transport down its...
ABC Transporters: Importer
In bacteria, based on the number of transmembrane helices and the chemical nature of their substrates, the ABC importers can be divided into three types:
Nonlinear Pharmacokinetics: Role of Transporters
Polymorphisms occurring in drug transporters can alter...
Drug Absorption Mechanism: Carrier-Mediated Membrane Transport
Facilitated diffusion is a passive process that utilizes human Solute Carrier (SLC) transporters. These transporters bind to the drug, undergo structural...
ABC Transporters: Exporter