Transport in and out of the nucleus is mediated by nuclear pore complexes (NPCs). Information has recently been emerging both on the structure of many of the proteins involved in this transport and on the complexes formed between them. In addition to NPC-based complexes, such as those based on nucleoporins Nsp1p and p62, cytoplasmic protein macromolecular assemblies are also important for nucleocytoplasmic transport.
Stewart, M., & Clarkson, W. D. (1996). Nuclear pores and macromolecular assemblies involved in nucleocytoplasmic transport. Current Opinion in Structural Biology. Elsevier Ltd. https://doi.org/10.1016/S0959-440X(96)80070-4