Exocyst complex component 4

EXOC4 is a component of the exocyst complex, a protein machinery responsible for docking exocytic vesicles at the plasma membrane (UniProt: Q96A65). The exocyst complex plays a critical role in regulated secretion and membrane trafficking, processes essential for neuronal function and synaptic communication.

EXOC4 is expressed in multiple tissues including the central nervous system, where it supports vesicular transport and cell surface protein delivery. UniProt records no primary disease associations for this protein, though exocyst dysfunction has been implicated in neurodevelopmental and neurodegenerative contexts given its role in membrane dynamics.

In Alzheimer's disease, EXOC4 shows decreased abundance in post-mortem brain tissue compared to age-matched controls (Chaparral AD proteomics). The protein was down-regulated across analyzed subcellular fractions with a mean log2 fold-change of −0.59, suggesting reduced exocyst availability in AD pathology. This reduction may reflect impaired secretory pathway function and compromised vesicular trafficking in the AD brain, potentially contributing to accumulation of misfolded proteins or defective synaptic transmission.