Fig. 4.

Structural model of human Artemis. (A) Overall structural model of Artemis. β-Lact and β-CASP are shown in pink and emerald green, respectively. The C-terminal fold-back of β-Lact is highlighted with light green. Positions of residues, the missense mutations of which are found in patients carrying Artemis deficiency, are shown in stick representation with yellow color. Zinc atoms are shown in sphere representation. (B) The catalytic center of Artemis. The same color scheme as (A) is used here. (C) Surface representation of β-CAPS. The positions of H228 an H254 are indicated. (D) Close-up view of the catalytic center of an archaeal RNase (PDB code: 3IEM; unpublished). Dotted lines denote hydrogen bonds.