Nup2 requires a highly divergent partner, NupA, to fulfill functions at nuclear pore complexes and the mitotic chromatin region.
Bottom Line: These mitotic problems are not caused by overall defects in mitotic NPC disassembly-reassembly or general nuclear import.However, without Nup2 or NupA, although the SAC protein Mad1 locates to its mitotic locations, it fails to locate to NPCs normally in G1 after mitosis.Collectively the study provides new insight into the roles of Nup2 and NupA during mitosis and in a surveillance mechanism that regulates nucleokinesis when mitotic defects occur after SAC fulfillment.
Affiliation: Laboratory of Gene Regulation and Development, National Institute for Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892.Show MeSH
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Mentions: Because Nup2 and NupA display identical dynamic subcellular localizations and cause similar mitotic defects when deleted (see below), it is possible that one could be responsible for the function of the other by targeting it correctly. To investigate this possibility, we deleted Nup2 in cells carrying NupA-GFP. In the absence of Nup2, NupA-GFP was able to locate to NPCs during interphase and to the chromatin region during mitosis (Figure 5B). In contrast, when nupA was deleted, Nup2-GFP was unable to locate to NPCs or to the mitotic chromatin region (Figure 5A). NupA is therefore required for Nup2 to locate to both interphase NPCs and the mitotic chromatin region.
Affiliation: Laboratory of Gene Regulation and Development, National Institute for Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892.