Identification and characterization of nuclear pore subcomplexes in mitotic extract of human somatic cells

In higher eukaryotic cells, it is generally thought that nuclear pore complex disassembles at the beginning of mitosis and reassembles at the end. Using a monoclonal antibody that recognizes nuclear pore antigens, we found that, at mitosis of mammalian somatic Hela cells, the nuclear pore complex disassembles into at least three subcomplexes, termed subcomplexes A, B and C (molecular mass; 2 MDa <, similar to 660 kDa, and similar to 440 kDa, respectively). The direct partial amino acid sequencing of the components of these subcomplexes indicates that the A subcomplex contains CAN/Nup214/p250 and p62 and the B subcomplex also contains p62, indicating that p62 is contained in two different subcomplexes. Subcomplex C was shown to consist of Nup98 and human RAE1, a human homolog of yeast Rae1p/Gle2p. Since Nup98 and Rae1p/Gle2p have been reported to be involved in mRNA export, this suggests that some of the mitotic subcomplex may be formed by functionally related proteins. (C) 1999 Academic Press.