Isoform D of Syntaxin-16

Syntaxin-16 isoform D (Syn16) is a member of the syntaxin family of soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) proteins encoded by the STX16 gene (UniProt: O14662-4). These proteins function as vesicular trafficking regulators, facilitating membrane fusion events essential for intracellular transport and secretory pathways.

Syntaxin-16 is broadly expressed across tissues and participates in vesicle docking and fusion machinery. The protein localizes to various intracellular compartments and contributes to transport processes involving the Golgi apparatus and endosomal systems (UniProt: O14662-4). No baseline disease associations are documented in UniProt annotation for this isoform.

In Alzheimer's disease, isoform D of Syntaxin-16 shows elevated abundance in post-mortem AD brain tissue relative to age-matched controls (Chaparral AD proteomics). The mean log2 fold-change is +1.1355 across examined subcellular fractions from TMT-labeled tandem mass spectrometry analysis of four fractions (P2, P3, S2, S3). This upregulation suggests potential dysregulation of vesicular trafficking machinery in AD neuropathology, though functional consequences remain to be determined.