Component of the nuclear pore complex, a complex required for the trafficking across the nuclear membrane. Component of the p62 complex, a complex at least composed of NUP62, NUP54, and NUP58. Interacts with NUTF2. Interacts with SRP1-alpha and Importin p97 proteins when they are together, but not with SRP1-alpha protein alone (By similarity). Biased towards cytoplasmic side. Central region of the nuclear pore complex, within the transporter. Contains FG repeats. FG repeats are interaction sites for karyopherins (importins, exportins) and form probably an affinity gradient, guiding the transport proteins unidirectionally with their cargo through the NPC. FG repeat regions are highly flexible and lack ordered secondary structure. The overall conservation of FG repeats regarding exact sequence, spacing, and repeat unit length is limited. O-glycosylated. In rat, the p62 complex contains two different isoforms of NUP58. Isoform p45 has however not been isolated in mouse so far. Belongs to the NUP58 family.