Structure of Lu gp D1D2. (A) Graphic representation in stereo showing the Lu gp structure. D1 is shown at the top and D2 at the bottom. The strands in each domain are labeled, as are the amino (N) and carboxy termini (C). (B) Overlay of Cα traces from the 3 independent copies of D1D2 in the 2 crystal structures. Orientation is as in panel A. (C) Location of residues that are altered in the known inherited forms of Lu gp that can be attributed to D1D2. Mutated residues are shown in stick form, and are colored as follows: Lu a/b is shown in red; Lu4, purple; Lu5, yellow; Lu8/14, blue; Lu12, pink; Lu16, gray; and Lu17, orange.