The C17ORF28 gene encodes an integral membrane protein belonging to the ‘inside-out’ class of membrane proteins. It consists of a cytoplasmic domain at its N-terminus, a single transmembrane peptide and an extracellular domain at its C-terminus. It is also found in the cytoplasm where it shuttles between the Golgi apparatus and the cytosol. As expression of the gene is seen to be reduced in several cancer cell lines, it has been suggested to play a role in tumor suppression. The gene is thus also designated as DMC1 or ‘Downregulated in Multiple Cancers-1’.
While the C17ORF28 gene is yet to be fully characterized, recent studies on lower orthologs have identified its role in the peptidergic signaling pathway, intracellular trafficking within the Golgi region and maturation of secretory granules generated at the trans-Golgi network. Two additional isoforms of the C17ORF28 protein exist due to alternatively spliced transcript variants. While the gene is expressed in the heart, skeletal muscle, colon, spleen, kidney, liver, small intestine and lung, highest expression is seen in the brain and placenta.