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Figure 1.
Figure 1. Crystal Structures of Rho/RhoGAP Complex(A) shows
the complex between the catalytic GAP domain of p50RhoGAP (α
helices shown as blue cylinders) and the Mg.GDP.MgF[3]^−
(shown as yellow ball and stick) complex of RhoA (α helices as
red cylinders and β strands in green). The catalytic arginine
residue (R85) from the GAP domain is shown in green interacting
with the metallo-fluoride moiety. The overall arrangements of
the two proteins and the interactions made at their interface
are very similar to those previously described for the
complex of RhoA.Mg.GDP.AlF[4]^−/RhoGAP [13]. The figure was
produced with the program Ribbons [29].(B) The top and bottom
panels show electron density maps for the “AlF[4]^−” and
“MgF[3]^−” complexes, respectively, together with a
ball-and-stick representation for the catalytic R85 from RhoGAP,
the GDP, and the metallo-fluoride moiety. The electron density
maps were calculated with (Fo − Fc) coefficients where the
amplitudes and phases were calculated from the atomic model with
the coordinates for R85 and the metallo-fluoride omitted from
the last cycles of refinement.(C) The top panel shows, in
ball-and-stick representation, molecular details of the active
site of the complex with “AlF[4]^−” while the bottom
panels show the same view for the complex with “MgF[3]^−.”
Arg 85 from RhoGAP is colored yellow while the residues from
RhoA are shown in gray. The GDP and metallo-fluoride moiety are
shown in magenta while water molecules are in green. The
distances for the various interactions shown are presented in
Table 3. The interactions of Lys18 and Gly62 of Rho with the
metallo-fluoride moiety have been omitted from this figure (but
not 2B and 2C) for clarity.
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