Figure 2.
Figure 2. Structural and sequence alignments of the semaphorins
and integrins. (a) Sequence alignments for the sema domain.
For the semaphorin sequences the extrusion and PSI domains are
boxed in blue and coral, respectively. Residues contributing to
the homodimerization interface in sSEMA4D are highlighted in
pink. A 70-residue section of the SEMA3A sequence implicated in
receptor specificity is green24. Residues that abolish function
when mutated in SEMA3A are cyan. Residues in SEMA3B and SEMA3F
implicated in cancer biology45, 46 (S. Naylor, personal
communication) are yellow.Secondary structure definitions for
sSEMA4D are above the sequence alignment, whereas those for the
integrin V
subunit (ITAV) are below. Cysteines conserved in the semaphorins
are highlighted in coral, and those conserved between the
semaphorins and integrin are in red. The figure was produced
using ESPript (http://prodes.toulouse.inra.fr/ESPript/). (b)
Structural comparison of the SEMA4D homodimer and integrin V
3
heterodimer. Structures are shown with equivalent propeller
orientations and, for clarity, include only the sema propeller
domains and the integrin propeller and A
domain core. Color coding for the reference propeller is as for
Figure 1a.
The above figure is reprinted
by permission from Macmillan Publishers Ltd:
Nat Struct Biol
(2003,
10,
843-848)
copyright 2003.
V
subunit (ITAV) are below. Cysteines conserved in the semaphorins
are highlighted in coral, and those conserved between the
semaphorins and integrin are in red. The figure was produced
using ESPript (http://prodes.toulouse.inra.fr/ESPript/). (b)
Structural comparison of the SEMA4D homodimer and integrin 
3
heterodimer. Structures are shown with equivalent propeller
orientations and, for clarity, include only the sema propeller
domains and the integrin propeller and