Figure 3.

Alignment of the three functional EF-hand domains in GCAP1. The α-helix and loop regions of the domain are identified above the sequences. Residues in the loop that coordinate the Ca²⁺ ion are marked with an asterisk. The invariant Glu residues at position 12 of each Ca²⁺-binding loop (E75, E111, and E155) are highlighted in bold. The positions of the E155G mutation in EF4 present in our pedigree and of the previously reported Y99C mutation in EF3 are boxed.