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Figure 1.
Figure 1. Organisation of the 30 SCR domains in sCR1. (a)
Schematic diagram showing the main features in the 30 SCR
domains. The long homologous repeats LHR-A to LHR-D are
indicated in bracketed ranges. sCR1 contains 25 putative
N-linked oligosaccharide sites (• and ○), of which the 14
sites used for the modelling of sCR1 are shown by ○. The six
sites underneath the cartoon schematically correspond to those
adjacent to β-strand β7. The three binding sites for C3b and
C4b at the start of LHR-A, LHR-B and LHR-C are also indicated.
(b) Sequence alignment of the 30 SCR domains in sCR1. Dashes are
used to preserve the alignment. The SCR sequence numbering of
the mature polypeptide (in brackets) is from residue 1 at the
start of the signal peptide (not shown). The four conserved Cys
residues (denoted C1–C4) and the conserved Trp residue are
highlighted in red. The inter-SCR linker sequences start after
the last Cys residue (C4) and end at the first Cys residue (C1)
in each SCR and are shown in green. The Thr1876Ile substitution
in SCR-29 is shown in blue (Materials and Methods). The six most
frequently conserved β-strands observed in the SCR models are
represented by grey shaded residues in the alignment according
to the DSSP analyses, and are labelled β2 and β4 to β8 to
follow previous conventions (see the text). The locations of the
25 putative N-linked oligosaccharide sites are shown in green
and yellow when these were used in the sCR1 models, and in red
and yellow when these were not used.
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