Figure 2. Sequence alignment of the two α-repeats in NCKX2, NCKX4, NCX1, and NCX_Mj. Colored red are the residues preserved in all four
systems. Boxed are the residues that form the ion binding sites in NCKX2 and NCX_Mj. Colored blue are additional residues preserved between
NCX1 and NCX_Mj.