Figure 2. Crystal Structure of the Canonical Dysferlin C2A Domain.

(A) Ribbon diagram of the stacked trimeric arrangement of the asymmetric unit of human dysferlin C2A. The green sphere is a single Ca²⁺ coordinated to one of the six domains in the asymmetric unit. Noncrystallographic 3-fold symmetry operators are represented as triangles.

(B) An isolated canonical C2A domain is shown in green.

(C) Ca²⁺ binding sites in dysferlin C2A. The green sticks correspond to the dysferlin C2A structure. The green sphere corresponds to the high-affinity Ca²⁺ found in the crystal structure (chain E, 4IHB). The yellow sticks correspond to the three La³⁺ described in the phospholipase C-δ1 C2 domain (1DJG, residues 628–756) (Essen et al., 1997). The residue numbers refer to the corresponding amino acids in the human dysferlin sequence.