Crystal structure of Thermococcus kodakaraensis GINS. (A) Domain organization of GINS from human, Thermococcus kodakaraensis, and Thermoplasma acidophilum. Cylinders represent A-domains mainly composed of α-helices and arrows show B-domains rich in β-strands. This coloring is used throughout the manuscript. The B domain of human Psf1 is missing in the crystal structures. (B) Ribbon representation of the structure. The Gins51 subunits are colored green, and the Gins23 subunits are cyan. Missing parts are shown with dotted lines. The crystallographic two-fold axis is indicated. The figure was prepared with PYMOL http://www.pymol.org.