Harvey rat sarcoma viral oncogene homolog protein (HRAS)

Harvey rat sarcoma viral oncogene homolog protein (HRas) is a small GTPase enzyme encoded by the human HRAS gene. It acts as a molecular switch within cells to regulate signal transduction pathways controlling growth factor responses, cell division, differentiation, and survival. In its active state bound to GTP, it propagates signals from activated receptors at the plasma membrane through effectors like Raf kinase into mitogenic pathways such as MAPK/ERK. Mutations that constitutively activate HRas are implicated in various cancers and developmental disorders like Costello syndrome. The protein cycles between active (GTP-bound) and inactive (GDP-bound) states; this cycling is tightly regulated but can be disrupted by genetic alterations leading to uncontrolled cellular proliferation.[1][5][7]

Other names

HRAS1v-Ha-ras Harvey rat sarcoma viral oncogene homologC-H-RASC-BAS/HASCTLOH-RASIDXHAMSVRASH1Transforming protein p21[1][2][4][6][8]

Drugs targeting HRAS typically act by inhibiting its GTPase activity or interfering with post-translational modifications required for membrane localization (e.g., farnesylation), thereby blocking downstream signaling pathways such as MAPK/ERK that drive cell proliferation and survival in cancers with activating HRAS mutations.