NSG2 (neuronal vesicle trafficking associated 2) is a small neuronal endosomal protein that functions as an AMPA receptor-binding protein at excitatory synapses 1. NSG2 localizes to discrete punctae in somatodendritic regions and colocalizes with postsynaptic HOMER1 and surface-expressed AMPA-type glutamate receptors (AMPARs) at excitatory synapses, where it physically interacts with GluA1 and GluA2 AMPAR subunits 1. Functionally, NSG2 is required for normal synapse formation and maintenance; NSG2 knockout in hippocampal neurons impaired miniature EPSC frequency and altered PSD95 expression, while overexpression increased mEPSC amplitude and GluA2 surface expression 1. Beyond neuronal function, NSG2 expression is upregulated during neuronal differentiation in response to protective compounds 2 and is involved in hematopoietic cell proliferation, where forced NSG2 expression promotes immature cell expansion and contributes to leukemogenesis through metabolic activation 3. NSG2 also emerges as a prognostic biomarker in breast cancer, where elevated expression in both cancer and stromal cells correlates with increased tumor size, metastasis, advanced stages, and altered immune cell infiltration 4. Additionally, NSG2 downregulation occurs early in hair cell stress responses during chr5 ototoxicity 5, and it functions as a prognostic gene in endometrial cancer 6.