GDNF family receptor alpha 2–RET receptor complex (GFRα2–RET)

The GDNF family receptor alpha 2 (GFRα2)–RET receptor complex is a multicomponent cell surface signaling unit primarily activated by the neurotrophic factor neurturin (NRTN) [1, 4]. It consists of the GPI-anchored co-receptor GFRα2, which provides ligand specificity, and the transmembrane receptor tyrosine kinase RET, which serves as the signaling subunit [2, 3]. Upon ligand binding, the complex typically forms a 2:2:2 heterohexamer, leading to the autophosphorylation of RET's intracellular kinase domain and the subsequent activation of downstream pathways such as MAPK/ERK and PI3K/Akt [3, 18]. This signaling is critical for the development, survival, and maintenance of specific neuronal populations, including parasympathetic, enteric, and sensory neurons [1, 15]. In a therapeutic context, the GFRα2–RET complex is a target for neurodegenerative conditions like Parkinson's disease and peripheral neuropathies, where agonists like neurturin or small-molecule mimetics (e.g., BT13, BT44) aim to promote neuronal repair and survival [7, 8, 12]. Conversely, the complex is often overexpressed or dysactivated in various malignancies, including neuroblastoma, pancreatic, and gastric cancers, where it contributes to tumor cell proliferation, invasion, and chemoresistance [3, 21]. Consequently, both agonistic strategies for neuroprotection and antagonistic approaches for oncology are under investigation [3, 7]. Challenges in targeting this complex include ensuring selectivity to avoid off-target RET activation and managing potential side effects such as thermal hypersensitivity or the promotion of tumor growth [3, 8].

Other names

Neurturin receptor complexNRTN-GFRα2-RET complexGDNFR-betaRETL2TRNR2NTNRAGDNF family receptor alpha 2-RET complex

Agonism of the RET receptor tyrosine kinase through the GFRα2 co-receptor to activate downstream survival and differentiation pathways [3, 12].