Figure 1.
Fig. 1. Structure of CD55. (a) Structure of the four SCR
domains (views at 0° and 90°). The molecule shown is
molecule A from crystal form A (see Table 2). The structure is
colored from blue at the N terminus to red at the C terminus.
All figures were drawn with AESOP (M. E. M. Noble, unpublished
program). (b) Comparison between eight copies of CD55[1234] from
three different crystal forms. The molecules are overlaid with
carbons from SCR domain
3 (residues 126-185) so that the lack of variation in the SCR
2/3 domain interface may be appreciated, and the molecules are
colored so that the two copies from crystal forms A and B are
red and green, respectively, and the four copies from crystal
form C are blue. (c) Full model for CD55 in the cell membrane.
This model combines the atomic coordinates for the SCR domains
with models for the N- and O-linked sugars and the GPI anchor,
built as described in the text. The molecule is embedded in a
lipid monolayer to allow the extension of the stalk that
supports the SCR domains above the membrane to be visualized.
carbons from SCR domain
3 (residues 126-185) so that the lack of variation in the SCR
2/3 domain interface may be appreciated, and the molecules are
colored so that the two copies from crystal forms A and B are
red and green, respectively, and the four copies from crystal
form C are blue. (c) Full model for CD55 in the cell membrane.
This model combines the atomic coordinates for the SCR domains
with models for the N- and O-linked sugars and the GPI anchor,
built as described in the text. The molecule is embedded in a
lipid monolayer to allow the extension of the stalk that
supports the SCR domains above the membrane to be visualized.