The Folinic acid calcium salt pentahydrate nuclear pore complex is a supramolecular protein assembly forming a highly selective channel embedded in the nuclear membrane. It regulates bidirectional nucleo-cytoplasmic transport for a large range of proteins and complexes too large to diffuse freely through the NPC. They are composed of numerous copies of,30 different nucleoporins, which have a well-assigned localisation, function and half-life, and are present as multiples of eight reflecting the highly conserved eight-fold axial symmetry of NPCs. The central substructure of the NPC is composed of transmembrane Nups that anchor the NPC to the nuclear envelope, scaffold Nups that constitute cornerstones during NPC biogenesis, and FG-Nups so-called because they contain extensive repeats of phenylalanine-glycine domains that form an unstructured mesh at the centre of the channel. Nup358/ RanBP2 and Nup214/CAN have been mapped exclusively to the cytoplasmic side of the NPC, where 50�C100 nm long flexible cytoplasmic filaments radiate from the NPC into the cytoplasm. Nup358/RanBP2 has been reported to be the major component of the cytoplasmic NPC filaments. Nup98 is a symmetrical nucleoporin, located on both the cytoplasmic and nuclear sides of the NPC. On the nuclear side of the NPC, Nups such as Nup153 and Nup98 associate with the nuclear basket and with the chromatin both in proximity of and away from the NPC. Many viruses depend on access to the nuclear compartment for replication and have evolved unique strategies to translocate into the nucleus. Retroviruses such as Murine Leukaemia Virus enter the nucleus during mitotic nuclear membrane disassembly, however other viruses such as herpesviruses and adenoviruses dock their capsids at the NPC and release their genome into the nucleus, while still others enter in the nucleus with their capsid. The Human Immunodeficiency Virus type 1, contrary to other orthoretroviruses, has evolved the ability to infect non-dividing cells through active nuclear Catharanthine sulfate import of its genome across the intact nuclear membrane through the NPC. Although several viral elements have been proposed to act as determinants of HIV-1 nuclear import, most notably integrase and the central DNA Flap, it is commonly accepted that HIV-1 depends on host cell proteins to achieve translocation. However, increasing data supports the presence of HIV-1 capsid at the nuclear pore and/or acting as a determinant of HIV-1 nuclear import. Uncoating certainly also occurs during cytoplasmic transport, and possibly accounts for the majority of incoming viral complexes. However, these may correspond to viral complexes destined for or undergoing degradation, for instance following entry by endocytosis. Our work shows that HIV-1 capsid interacts with Nup358/RanBP2 and that depletion of Nup358/RanBP2 impairs arrival of HIV-1 complexes at the nuclear envelope, thus confirming the presence of HIV-1 capsid cores at the nuclear membrane. However, our study does not show any effect for Nup358 in integration, since the strong reduction in proviral integration is simply due to a strong nuclear import defect and considering the exclusive cytoplasmic location of Nup358/RanBP2 we do not expect to find its potential viral partner in the nucleus. We cannot exclude that the absence of this nucleoporin could affect HIV-1 site integration but that may reflect 
the change of chromatin environment associated with depletion of Nup358. In this work, we identified Nup358/RanBP2 as docking factor for HIV-1 capsid using independent techniques to assess docking and interaction. We are the first to identify the binding of Nup358/ RanBP2 to HIV-1 in vitro assembled CA-NC complexes suggesting that this interaction is important for HIV-1 nuclear import. Nup358/RanBP2 is one of over 20 human proteins that contain a cyclophilin-like domain.