Quantification of the vitamin D receptor-coregulator interaction
Arnaud Teichert1, Leggy A Arnold, Steve Otieno
1Endocrine Unit, University of California, San Francisco, San Francisco, California 94121, USA.
Biochemistry
|February 3, 2009
Summary
The vitamin D receptor (VDR) interacts with coregulator proteins, influencing gene activity. Similar binding patterns were observed for both natural and synthetic ligands, aiding in developing targeted vitamin D therapies.
Area of Science:
- Endocrinology
- Molecular Biology
- Genetics
Background:
- The vitamin D receptor (VDR) is crucial for regulating genes involved in bone health, immunity, and hair growth.
- Ligand binding to VDR induces conformational changes, affecting corepressor and coactivator protein interactions essential for gene transcription.
Purpose of the Study:
- To comprehensively evaluate the interaction of VDR with various coregulator binding motifs.
- To compare VDR interactions with its natural ligand (1alpha,25(OH)(2)D(3)) and a synthetic agonist (LG190178).
Main Methods:
- Utilized a library of coregulator binding motifs to assess VDR interactions.
- Investigated VDR binding affinities in the presence of both 1alpha,25(OH)(2)D(3) and LG190178.
Main Results:
- VDR demonstrated high affinity for specific LxxLL motifs in SRC1, SRC2, SRC3, and DRIP205, a pattern distinct from other nuclear receptors.
- Binding affinity patterns were highly consistent between the natural ligand and the synthetic agonist LG190178.
- Hairless protein binds VDR via an LxxLL motif, repressing transcription irrespective of ligand presence.
Conclusions:
- The consistent VDR-coregulator binding patterns for both ligands suggest similar biological functions.
- Identified VDR binding patterns can predict tissue-specific functional differences based on coregulator expression.
- Findings facilitate the development of targeted modulators for tissue- and gene-specific vitamin D responses.
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