Calcium-dependent phospholipid-binding protein that may play a role in calcium-mediated intracellular processes. Translocates to the cell membrane in a calcium-dependent manner. The C2 domain 1 is not necessary for calcium-mediated translocation and association to the plasma membrane. The C2 domain 2 is necessary for calcium-mediated translocation and association to the plasma membrane. Belongs to the copine family.