Embryonic stem cell-expressed Ras (ERAS)

Embryonic stem cell-expressed Ras (ERAS) is a constitutively active GTPase belonging to the Ras family, expressed primarily in undifferentiated embryonic stem cells and specific contexts such as quiescent hepatic stellate cells and certain tumors. Unlike canonical RAS isoforms, ERAS is not detected in most adult tissues under normal conditions. Its protein activates the PI3K–AKT signaling pathway, contributing to cell survival, proliferation, and stemness features. Aberrant expression of ERAS is implicated in the development and progression of multiple cancers, including breast, gastric, pancreatic, and colorectal cancers. Its constitutive activity (insensitivity to GAP inactivation) is a distinctive property, making it a potential oncogenic driver when abnormally expressed in adult cells.

Other names

GTPase ERasHRAS2HRASPE-Rassmall GTPase protein E-Rasv-Ha-ras Harvey rat sarcoma viral oncogene homolog 2v-Ha-ras Harvey rat sarcoma viral oncogene homolog pseudogeneembryonic stem cell-expressed Ras

Constitutive activation of PI3K–AKT pathway; does not activate the RAF–MEK–ERK pathway but preferentially activates PI3Kα over other effectors