KRAS protein contains four domains.br br KRAS protein is made up of six beta-strands (forming the protein core) and five alpha-helices, which form two major domains: G-domain and C-terminal.br br The G domain of KRAS, comprised of residues 1-166, includes the GTP-binding pocket, a region within which is essential for the interactions between the putative downstream effectors and GTPase-activating proteins.