Figure 1

TRPV6 simulated system. Truncated TRPV6 (see Methods) is shown in lipid bilayer and water in the presence of Na⁺ and Ca²⁺ ions. For all simulations, composition of protein/lipid/water remained the same, while composition of ions varied (see text). The model protein consisted of the pore domain (S5, P-loop, and S6) and a truncated TRP helix (residues K483 to Q595, not shown). The protein (cyan) is shown in cartoon representation. Pore lining residues D541, T538, and M569 are shown as yellow sticks. The POPC lipid head-groups are shown as colored spheres: oxygen is red, phosphorus is orange, and nitrogen is blue. The hydrocarbon lipid tails (pink) are shown in stick representation. Ca²⁺ and Na⁺ ions are shown as green and white spheres, respectively, and water is illustrated by a semi-transparent continuum (blue).