Molecular modeling of ACTG containing the p.G268S mutation. (A) Ribbon model of filamentous actin gamma 1. (B) Magnified ribbon model of filamentous actin gamma 1. Glycine residue 268 is shown in red and indicated by an arrow. Regions in yellow and green indicate the hydrophobic loop (262–274; a) and the corresponding interactive residues (281–289; b), respectively. (C and D) Vertical views of the regions a and b superimposed with predicted surface hydrophobicity in the wild type (C) and the p.G268S mutant (D).