Ran GTPase is a master regulatory switch, which among other functions, controls the shuttling of proteins between the nuclear and cytoplasm compartments of the cell.

The RanBP2 gene encodes a very large RAN-binding protein that localizes to cytoplasmic filaments emanating from the nuclear pore complex.

Each domain of RanBP2 selectively and directly interacts with distinct proteins such as Ran GTPase, importin-beta, exportin-1/CRM1, red opsin, subunits of the proteasome, cox11 and the kinesin-1 isoforms, KIF5B and KIF5C.

The pleiotropic (multifunctional) role of RanBP2 reflects its interaction with multiple partners, each presenting distinct cellular or molecular functions.

Insufficiency of RanBP2 is directly linked to carcinogenesis, aneuploidy, and neuroprotection of photoreceptor neurons to light-elicited stress and aging.