Fig. (1).

A. The homodimeric CaR complex. The ATD, CRR and 7TM regions of the receptor are indicated. The residues in the ATD involved in Ca²⁺ and L-α-amino acid binding and the residues in the 7TM involved in the binding of calcimimetics and calcilytics are given. B. The signal transduction through the CaR homodimer when exposed to Ca²⁺ alone, Ca²⁺ and L-α-amino acids, Ca²⁺ and calcilytics, and Ca²⁺ and calcimimetics. Inactive and active conformations of the CaR homodimer is given in red and green, respectively.