The RAS protein subfamily is a subgroup of the RAS superfamily of proteins. These proteins are expressed in all cells are involved in signal transmission.
When RAS is switched on it switches on other proteins which ultimately result in turning on genes that result in an alteration in cell growth, differentiation and survival.
There are three RAS genes involved in coding for the RAS protein subfamily:
- HRAS: Harvey rat sarcoma viral oncogene
- KRAS: Kirsten rat sarcoma viral oncogene
- NRAS: neuroblastoma RAS viral oncogene homolog
The RAS proteins have a similar 3D structure and a molecular weight of 21 kDa. They play a key role in the signal transduction from the membrane to the nucleus. RAS proteins are GNP-binding proteins that function as on-off molecular switches to control intracellular signaling networks.
Cascade pathways activated by RAS include:
- mitogen-activated protein kinase (MAPK) pathway
- PI3K/AKT/mTOR pathway
RAS-regulated pathways control numerous cellular processes:
- actin cytoskeletal integrity
- cell proliferation
- cell differentiation
- cell adhesion
- cell migration