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Updated: Jul 9, 2026
09:35
Real Time Measurements of Membrane Protein:Receptor Interactions Using Surface Plasmon Resonance (SPR)
Published on: November 29, 2014
A functional steroid-binding element in an ATP-binding cassette multidrug transporter
Saroj Velamakanni1, Tavan Janvilisri, Sanjay Shahi
1Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom.
Molecular Pharmacology
|December 21, 2007
Summary
Researchers identified a steroid-binding element in the breast cancer resistance protein (BCRP), a key transporter affecting chemotherapy efficacy. This discovery may lead to new drugs targeting BCRP and improving cancer treatment.
Area of Science:
- Biochemistry
- Molecular Biology
- Pharmacology
Background:
- The breast cancer resistance protein (BCRP), an ABCG2 transporter, influences chemotherapeutic drug bioavailability and cancer drug resistance.
- Members of the ABCG subfamily are linked to human steroid-related disorders, but the molecular basis of protein-steroid interactions in ABC transporters remains unclear.
Purpose of the Study:
- To identify the molecular basis of steroid interactions within the ABCG2 transporter.
- To characterize a novel steroid-binding element in ABCG2 and its functional implications.
Main Methods:
- Bioinformatic analysis to identify structural similarities.
- Functional assays to assess steroid binding and modulation of ABCG2 activity.
Main Results:
- A steroid-binding element with similarity to steroid hormone/nuclear receptors was identified in the membrane domain of ABCG2.
- This element was shown to facilitate steroid hormone binding and modulate ABCG2 transporter activity.
Conclusions:
- The identified steroid-binding element is crucial for ABCG2-steroid interactions.
- This finding offers a potential target for developing novel therapeutic ligands to modulate ABCG2 activity, impacting cancer therapy and steroid-related diseases.
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