Figure 2.

Schematic representation of the CaR's Cysteine rich domain. The Cys-rich (CR) domain has nine conserved cysteine residues (black circles), all of which are predicted to participate in di-sulfide bonds (broken lines). In total there are four predicted intra-domain di-sulfides and one disulfide between CaR residues 561 in the CR domain and 236 in lobe 2 of the VFT domain. A 14 amino acid linker (grey circles) supports signal transmission from the VFT domain to the heptahelical domain. CaR, calcium-sensing receptor; VFT domain, Venus Fly Trap domain.