Unknown. Cellular response protein to viral infection. Interacts with DYM. Early Golgi. Cycles via the cell surface and endosomes upon lumenal pH disruption. Up-regulated in response to viral infection. Glycosylated. Phosphorylation sites are present in the extracellular medium. Belongs to the GOLM family. It is uncertain whether Met-1 or Met-2 is the initiator.