Neuroblastoma RAS viral oncogene homolog (NRAS)–Phosphoinositide 3-kinase alpha (PI3Kα) interface (NRAS–PI3Kα interface)

The NRAS–PI3Kα interface is the physical contact site between the Neuroblastoma RAS viral oncogene homolog (NRAS) and the p110α catalytic subunit of Phosphoinositide 3-kinase (PI3K) (UniProt P01111, P42336). This interaction is a pivotal node in the signal transduction network, where active, GTP-bound NRAS binds to the Ras-binding domain (RBD) of PI3Kα to trigger the PI3K/AKT/mTOR signaling cascade (Gupta et al., 2007). This pathway is essential for regulating cell growth, survival, and metabolism. In various malignancies, most notably NRAS-mutant melanoma, this interface is hyperactivated, driving uncontrolled tumor cell proliferation and resistance to apoptosis. Unlike traditional PI3K inhibitors that target the ATP-binding pocket, therapeutic strategies focusing on this interface aim to disrupt the specific protein-protein interaction (PPI). By preventing NRAS from recruiting and activating PI3Kα at the plasma membrane, these inhibitors can potentially achieve higher selectivity for RAS-driven cancers while minimizing the systemic toxicities associated with broad PI3K inhibition. Current drug development efforts include small-molecule disruptors and peptidomimetics designed to block the RBD, with agents like Rigosertib being investigated for their ability to interfere with RAS-effector interactions (Athuluri-Divakar et al., 2016).

Other names

NRAS-p110α interfaceNRAS-PIK3CA interaction siteRAS-PI3K interfaceNRAS-PI3K interaction

Inhibition of the protein-protein interaction between NRAS and the Ras-binding domain (RBD) of the p110α catalytic subunit of PI3K, preventing RAS-mediated activation of the PI3K/AKT/mTOR pathway.