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Updated: Aug 14, 2026
10:43
Expression, Detergent Solubilization, and Purification of a Membrane Transporter, the MexB Multidrug Resistance Protein
Published on: December 3, 2010
Membrane transporters in drug disposition
1Department of Biopharmaceutical Sciences, University of California, San Francisco 94143-0446, USA.
Journal of Pharmacokinetics and Biopharmaceutics
|August 11, 1998
Summary
Researchers cloned novel organic cation transporters (OCTs) from rat and human kidneys. These findings advance understanding of drug elimination and can aid in drug discovery and development.
Area of Science:
- Pharmacology
- Molecular Biology
- Renal Physiology
Background:
- Many drugs, metabolites, and toxins are organic cations at physiological pH.
- Renal proximal tubule secretion is a key elimination pathway for organic cations.
Purpose of the Study:
- To molecularly clone and characterize novel organic cation transporters (OCTs).
- To investigate the role of RNA splicing in transporter diversity.
- To explore interspecies differences in OCT tissue distribution and function.
Main Methods:
- Molecular cloning of rat kidney organic cation transporter 1 splice variant (rOCT1A).
- Functional characterization of cloned transporters.
- Molecular cloning of the first human organic cation transporter (hOCT1).
Main Results:
- A novel splice variant, rOCT1A, was identified, highlighting RNA splicing's role in transporter diversity.
- The first human organic cation transporter, hOCT1, was cloned.
- Significant interspecies differences in hOCT1 tissue distribution and function were observed.
Conclusions:
- These cloned OCTs provide tools for elucidating structure-function relationships and the physiological role of organic cation transport.
- The transporters can be utilized in mammalian expression systems for drug screening and pharmacokinetic prediction.
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