Structure comparison with apo-CPILE-a, NAD⁺-CPILE-a, NADH-CPILE-a and close-up view of NAD-binding site of CPILE-a, Ia and BECa.

<p><b>A,</b> Superimposed structures of NAD⁺-CPILE-a and apo-CPILE-a indicated that the binding to NAD⁺ did not induce conformational change to CPILE-a. The N-terminal domain and the C-terminal domain of NAD⁺-CPILE-a are shown in marine and yellow, respectively. The apo-CPILE-a is shown in orange. <b>B,</b> Superimposed structures of NAD⁺-CPILE-a and NADH-CPILE-a (lime green) showed very similar structure with r.m.s.d. 0.23 (Å). <b>C,</b> Superimposed structures of NAD⁺-CPILE-a and Ia (4H03). Ia and actin showed in white and green, respectively. <b>D,</b> Stereo-view of NAD⁺-CPILE-a (yellow) and NAD⁺-Ia (4H03) focused on ligand-binding site (NAD⁺). Ten residues represent the close-contact residues to the NAD⁺. All residues labeled here belong to the NAD⁺-CPILE-a. <b>E,</b> Stereo-view of the 2Fo-Fc electron density map of the NAD⁺ contoured at 2σ. <b>F,</b> Superimposed structure of NADH-CPILE-a, apo-BEC-a (5H03), and NADH-BECa (5H04) focused on ligand binding site. A distinct residue (Tyr377) on the ARTT-loop is shown in stick model. The NAD⁺-CPILE-a, NADH-CPILE-a, apo-BECa, and NADH-BECa are shown in yellow, green, tint, and split pea, respectively.