VAMP-Associated Protein A ( or Vesicle-Associated Membrane Protein-Associated Protein A) is a protein that in humans is encoded by the VAPA gene. Together with VAPB and VAPC it forms the VAP protein family. They are integral endoplasmic reticulum membrane proteins of the type II and are ubiquitous among eukaryotes. VAPA is ubiquitously expressed in human tissues and is thought to be involved in membrane trafficking by interaction with SNAREs, in regulation of lipid transport and metabolism, and in the Unfolded Protein Response (UPR).