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Structure-function relationship of the extracellular calcium-sensing receptor
1Department of Medicine, Division of Endocrinology, Diabetes, and Hypertension, Brigham and Women's Hospital, 221 Longwood Ave., Boston, MA 02115, USA. mbai@rics.bwh.harvard.edu
Cell Calcium
|June 18, 2004
Summary
The calcium-sensing receptor (CaR) regulates calcium levels. Mutations in CaR cause hypercalcemic and hypocalcemic disorders, offering insights into receptor function and disease pathogenesis.
Area of Science:
- Endocrinology
- Molecular Biology
- Cell Biology
Background:
- The extracellular calcium-sensing receptor (CaR) is a G protein-coupled receptor crucial for calcium homeostasis.
- CaR's role in sensing and regulating extracellular calcium is vital, as evidenced by associated genetic disorders.
Purpose of the Study:
- To elucidate the regulation and activation processes of the CaR.
- To understand CaR structure-function relationships, including dimerization.
- To clarify the pathogenesis of CaR-related clinical conditions.
Main Methods:
- Stable and transient expression of CaR in human embryonic kidney cells.
- Physiological, biochemical, and molecular biological techniques.
- Characterization of naturally occurring CaR mutations.
Main Results:
- Established the physiological relevance of CaR in calcium regulation.
- Identified inactivating and activating CaR mutations linked to hypocalcemic and hypercalcemic disorders, respectively.
- Utilized CaR mutations to study structure-function relationships and receptor dimerization.
Conclusions:
- CaR mutations are key to understanding calcium-sensing disorders.
- Naturally occurring CaR mutations provide insights into receptor function and disease mechanisms.
- Characterization of CaR mutations clarifies the pathogenesis of familial hypocalciuric hypercalcemia and neonatal severe hyperparathyroidism.
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