Functional interactions between nucleoporins and chromatin - PubMed (original) (raw)

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Functional interactions between nucleoporins and chromatin

Yun Liang et al. Curr Opin Cell Biol. 2011 Feb.

Abstract

As the gatekeepers of the eukaryotic cell nucleus, nuclear pore complexes (NPCs) mediate all molecular trafficking between the nucleoplasm and the cytoplasm. In recent years, transport-independent functions of NPC components, nucleoporins, have been identified including roles in chromatin organization and gene regulation. Here, we summarize our current view of the NPC as a dynamic hub for the integration of chromatin regulation and nuclear trafficking and discuss the functional interplay between nucleoporins and the nuclear genome.

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Figures

Figure 1

Figure 1

Nup-gene association. Vertebrate Nups are shown based on the functions of corresponding homologues in yeast or Drosophila. Subcomplexes of the NPC that are composed of scaffold Nups are colored in blue. Nups that show preferential association with active genes are shown in green. Nup88, the only Nup found to interact with repressed loci, is shown in red [17,18••,19••,20••]. Nups that are linked to both active and repressed genes are shown in orange [17, 47]. Nic96, the Nup93 homologue in yeast, preferentially associates with active genes. By contrast, human Nup93 targets in Hela cells are enriched for repressive histone marks. Asterisks indicate Nups with intranuclear (i.e. away from the pore) gene association. One or more of the Nups in parenthesis (Nup62, Nup153, Nup214, and Nup358), recognized by 414 antibody, interact with active genes in the nucleoplasm in Drosophila salivary glands [20••].

Figure 2

Figure 2

Signal-induced alterations in Nup regulation of gene activities may be achieved by genome reorganization that results in different sets of genes being positioned at the NPCs, Nup relocalization to new intranuclear loci, or both. One example of Nup relocalizing to intranuclear genes in response to signaling is shown.

Figure 3

Figure 3

NPCs function in gene looping, organization of chromatin domains, and coordination of transcription and export. Vertebrate Nups are shown based on the functions of corresponding homologues in yeast or Drosophila. Nup2 (vertebrate homologue Nup153) and Megator (vertebrate homologue Tpr) can protect active regions from heterochromatin spreading, and the SAGA complex may mediate the barrier activity of NPCs [–43]. Mlp1 (vertebrate homologue Tpr) is required for the maintenance of memory gene loops and possibly sequestration of transcription factors during repression, allowing the associated gene to be reactivated faster [45]. In addition, NPCs may be cotranscriptionally tethered to genes by THO/TREX and/or SAGA-TREX-2 complexes [33••,20••]. SAGA complex is also present at coding regions apart from promoters [32], which is omitted here for simplicity. Mlp1 (vertebrate homologue Tpr) can be copurified with SAGA complex, and they associate with the same region of GAL promoters [45]. Sac3 (TREX-2 component) copurified with Nup1 (vertebrate homologue Nup153), and requires Nup1 for NPC anchoring [27]. SAGA-TREX-2 and THO/TREX complexes may physically interact [27, 46]. THO mutation resulted in a stalled mRNA intermediate associated with Nup60 (vertebrate homologue Nup153) and Nup116 (related to vertebrate Nup98), suggesting that THO coordination of mRNP formation and export may involve these two Nups [34••]. Abbreviations: 98, Nup98; 153, Nup153; polII: RNA polymerase II.

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References

    1. Hetzer MW, Walther TC, Mattaj IW. Pushing the envelope: structure, function, and dynamics of the nuclear periphery. Annu Rev Cell Dev Biol. 2005;21:347–380. - PubMed
    1. Rout MP, Aitchison JD, Suprapto A, Hjertaas K, Zhao Y, Chait BT. The yeast nuclear pore complex: composition, architecture, and transport mechanism. J Cell Biol. 2000;148:635–651. - PMC - PubMed
    1. Chadrin A, Hess B, San Roman M, Gatti X, Lombard B, Loew D, Barral Y, Palancade B, Doye V. Pom33, a novel transmembrane nucleoporin required for proper nuclear pore complex distribution. J Cell Biol. 2010;189:795–811. Identification of a novel trnasmembrane Nups, suggesting that more NPC components might be discovered in the future. - PMC - PubMed
    1. Rabut G, Doye V, Ellenberg J. Mapping the dynamic organization of the nuclear pore complex inside single living cells. Nat Cell Biol. 2004;6:1114–1121. - PubMed
    1. D’Angelo MA, Anderson DJ, Richard E, Hetzer MW. Nuclear pores form de novo from both sides of the nuclear envelope. Science. 2006;312:440–443. - PubMed

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