FIG. 5.

Molecular modeling of the RasGRD of GAP1^IP4BP. (A) The sequence alignment used for modeling of GAP1^IP4BP and GAP1^m on p120^GAP (GRD 1WER) and TAPP1 (PH domain 1EAZ). The secondary structure of the templates is indicated as follows: helix, wavy overlining; sheet, zigzag overlining. Residue identities are in red, and similarities are in magenta. The asparagine and glutamine residues in GAP1^IP4BP that were mutated to alanine are underlined. (B) Structure of the Ras/p120^GAP complex (1WQ1). The p120^GAP GRD is shown as a light blue ribbon with the residues beyond L991 shown in yellow. Ras is shown as a green ribbon, GDP is shown as pink sticks, and R789 is shown as orange sticks. (C) Model of the Ras/GAP1^IP4BP complex. The GAP1^IP4BP GRD (modeled on p120^GAP) is shown as a cyan ribbon with the residues beyond E573 shown in dark blue and modeled as a PH domain. Ras is shown as a green ribbon, GDP is shown as pink sticks, and R371 is shown as orange sticks.