The nuclear pore complex (NPC) mediates bidirectional macromolecular traffic between the nucleus and cytoplasm in eukaryotic cells and is comprised of more than 100 different subunits. Many of the subunits belong to a family called nucleoporins (Nups), which are characterized by the presence of O-linked-N-acetylglucosamine moieties and a distinctive pentapeptide repeat (XFXFG). gp210, also known as Nup210 (nucleoporin 210kDa) or POM210, is a 1,887 amino acid single-pass type I membrane protein that localizes to both the endoplasmic reticulum and to the nucleus, specifically within the NPC. Expressed ubiquitously with highest expression in pancreas, testis, lung, ovary and liver, gp210 functions as a nucleoporin that is capable of dimerization and is essential for the assembly, fusion and structural integrity of the NPC. gp210 exists as multiple alternatively spliced isoforms and is subject to post-translational phosphorylation.