Neuroblastoma RAS viral oncogene homolog-Rapidly Accelerated Fibrosarcoma Ras-binding domain interaction (NRAS-RAF-RBD interaction)

The NRAS-RAF-RBD interaction is a fundamental molecular event in the MAPK/ERK signaling cascade, involving the binding of GTP-loaded Neuroblastoma RAS viral oncogene homolog (NRAS) to the Ras-binding domain (RBD) of RAF kinases such as CRAF or BRAF (UniProt: P01111, P04049). This interaction facilitates the recruitment of RAF to the plasma membrane, where it undergoes dimerization and activation, ultimately driving cell proliferation and survival (PubMed: 27058662). In clinical contexts, oncogenic mutations in NRAS, such as Q61K or G12D, result in a constitutively active protein that continuously recruits RAF, leading to the development of various malignancies including melanoma and acute myeloid leukemia (NIH: Cancer Stat Facts). Targeting this specific protein-protein interaction (PPI) has become a major focus in oncology to address the undruggable nature of RAS by using small molecules or mimetics to sterically block the interface (PubMed: 30545852). For instance, rigosertib has been described as a RAS-mimetic that disrupts the interaction between RAS and the RBD of its effectors, although its precise clinical utility remains under investigation (Cell: 165(3)). Successfully inhibiting this interaction provides a pathway to suppress hyperactive MAPK signaling in NRAS-driven tumors while navigating the challenges of systemic toxicity and acquired resistance (PubMed: 31812374).

Other names

NRAS-RAF interactionNRAS-CRAF interactionNRAS-BRAF interactionNRAS-RAF protein-protein interaction

Small molecules or mimetics bind to either the RAS switch regions or the RAF Ras-binding domain (RBD) to sterically hinder the formation of the NRAS-RAF complex, thereby blocking the activation of the downstream MAPK/ERK signaling cascade.