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This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License. ; Nuclear pore complexes consist of several subcomplexes. The NUP107 complex is important for nucleocytoplasmic transport, nuclear envelope assembly, and kinetochore function. However, the underlying molecular mechanisms and the roles of individual complex members remain elusive. We report the first description of a genetic disruption of NUP107 in a metazoan. Caenorhabditis elegans NUP107/npp-5 mutants display temperature-dependent lethality. Surprisingly, NPP-5 is dispensable for incorporation of most nucleoporins into nuclear pores and for nuclear protein import. In contrast, NPP-5 is essential for proper kinetochore localization of NUP133/NPP-15, another NUP107 complex member, whereas recruitment of NUP96/NPP-10C and ELYS/MEL-28 is NPP-5 independent. We found that kinetochore protein NUF2/HIM-10 and Aurora B/AIR-2 kinase are less abundant on mitotic chromatin upon NPP-5 depletion. npp-5 mutants are hypersensitive to anoxia, suggesting that the spindle assembly checkpoint (SAC) is compromised. Indeed, NPP-5 interacts genetically and physically with SAC protein MAD1/MDF-1, whose nuclear envelope accumulation requires NPP-5. Thus our results strengthen the emerging connection between nuclear pore proteins and chromosome segregation. © 2012 Tatavarty et al. ; This work was funded by the Spanish Ministry of Science and Innovation (BFU-2007-60116, BFU-2010-15478), the Spanish National Research Council (200820I028), the European Regional Development Fund, and the Regional Government of Andalusia (P07-CVI-02697). In addition, we acknowledge the Fundación Ramón Areces for a fellowship to E.R. and the Junta de Andalucía for institutional support. Some nematode strains used in this work were provided by the National Bioresource Project for the Nematode C. elegans (directed by Shohei Mitani), the C. elegans Gene Knockout Consortium, and the Caenorhabditis Genetic Center (University of Minnesota, Minneapolis, MN), which is funded by the National Institutes of Health, National Center for Research Resources. ; Peer Reviewed

Nuclear envelope (NE) architecture and aging have been associated since the discovery that certain human progeria diseases are due to perturbations in processing of lamin A protein, generating alterations in NE morphology. However, whether changes in the NE are a causal effect of normal and premature aging is still controversial. Caenorhabditis elegans is a model organism where observations supporting both, dependent and independent roles of nuclear architecture in the aging process, have been reported. We found that the long-lived glp-1 mutant and dietary restriction delayed age-associated nuclear morphology changes. In addition, we observed that the long-lived mutant of the insulin/IGF receptor daf-2 delayed the age-dependent changes of nuclear architecture at 25 °C, as previously described. However, when daf-2 animals were incubated at 20 °C they remained long-lived, but nuclear appearance changed at similar rate as in the wild type. This supports the idea that both phenotypes, longevity and maintenance of nuclear architecture are tightly associated but can be separated and argues that nuclear morphology deterioration is not a cause of the natural aging process. ; This work was funded by the Autonomous Government of Andalusia (P07-CVI- 02697). In addition, we wish to acknowledge Fundación Ramón Areces for a fellowship to ER. Some nematode strains used in this work were provided by the ''Caenorhabditis Genetic Center'', which is funded by the NIH National Center for Research Resources (NCRR). ; Peer Reviewed