Gamma-soluble NSF attachment protein

Gamma-soluble NSF attachment protein (SNAP-gamma), encoded by NAPG, is a 312-amino acid protein required for vesicular transport between the endoplasmic reticulum and the Golgi apparatus (UniProt: Q99747). It functions as a component of the SNARE machinery that facilitates membrane trafficking and protein secretion. The protein is ubiquitously expressed across tissues supporting active protein synthesis and secretion pathways.

NAPG is associated with Alzheimer's Disease based on Chaparral proteomics curation. Post-mortem AD brain tissue shows reduced NAPG abundance compared to age-matched controls in a TMT-labeled quantitative proteomics study analyzing four subcellular fractions (P2, P3, S2, S3) via data-dependent acquisition mass spectrometry. The mean log2 fold-change is −0.194, indicating modest downregulation of the protein in AD brain (Chaparral AD proteomics). This reduction in a vesicular transport factor may reflect disrupted secretory pathway function or altered membrane dynamics associated with neurodegeneration.