Fig. 2

Structure of a single LjCASTOR soluble subunit. a The LjCASTOR soluble subunit contains two RCK domains with two clusters of ion-binding sites: pink, RCK1 (residues 320–552); green, RCK2 (residues 581–853); gray, RCK1–RCK2 linker (553–580); a dotted line, residues 699–726 with no electron density; orange sphere, Ca²⁺; yellow sphere, Mg²⁺; purple sphere, Na⁺. b Topology and domain organization of the two RCK domains of LjCASTOR