Ras-interacting protein 1 (RASIP1)

Ras-interacting protein 1 (RASIP1) is an adapter protein predominantly expressed in endothelial cells, where it functions as an effector for small GTPases such as Rap1 and Ras[2][5]. RASIP1 is essential for vascular development, mediating vasculogenesis and angiogenesis by regulating cytoskeletal organization, cell adhesion, and endothelial cell junction integrity[1][4][5]. Mechanistically, RASIP1 interacts with Rap1 and suppresses RhoA/ROCK signaling through recruitment of ARHGAP29, enabling proper cell spreading and maintaining vascular barrier function[1][3][4]. RASIP1 also binds directly to the cytoplasmic domain of the transmembrane protein Heart of Glass (HEG1), anchoring it to endothelial cell-cell junctions[4]. Knockdown or genetic deletion of RASIP1 leads to profound defects in blood vessel formation and vascular collapse[4][5], and genetic variants in RASIP1 have recently been associated with late-onset Alzheimer's disease risk[3]. No drugs are known to target RASIP1 directly, but its central role in vascular health makes it a potential therapeutic target for cardiovascular and inflammatory diseases, with notable risks if inhibited due to its essential role in endothelial function[4][5].

Other names

RASIP1Rainras-interacting protein 1FLJ20401RAIN

Adapter/linker for small GTPases (Rap1 and Ras), modulating RhoA and ROCK signaling. It interacts with ARHGAP29 to suppress RhoA signaling. RASIP1 maintains vascular integrity via cytoskeletal dynamics and cell junctions.