Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Nucleoporin Elys attaches peripheral chromatin to the nuclear pores in interphase nuclei

ABSTRACT: Transport of macromolecules through the nuclear envelope (NE) is mediated by nuclear pore complexes (NPCs) consisting of nucleoporins (Nups). Elys/Mel-28 is the Nup that binds and connects the decondensing chromatin with the reassembled NPCs at the end of mitosis. Whether Elys links chromatin with the NE during interphase is unknown. Using DamID-seq, we identified Elys binding sites in Drosophila late embryos and divided them into those associated with nucleoplasmic or NPC-linked Elys. These Elys binding sites are located within active or inactive chromatin, respectively. Strikingly, Elys knockdown in S2 cells results in peripheral chromatin displacement from the NE, in decondensation of NE-attached chromatin, and in derepression of genes within. It also leads to slightly more compact active chromatin regions. Our findings indicate that NPC-linked Elys, together with the nuclear lamina, anchors peripheral chromatin to the NE, whereas nucleoplasmic Elys decompacts active chromatin.

ORGANISM(S): Drosophila melanogaster

PROVIDER: GSE219152 | GEO | 2024/07/01

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Nucleoporin Elys attaches peripheral chromatin to the nuclear pores in interphase nuclei

Project description:Transport of macromolecules through the nuclear envelope (NE) is mediated by nuclear pore complexes (NPCs) consisting of nucleoporins (Nups). Elys/Mel-28 is the Nup that binds and connects the decondensing chromatin with the reassembled NPCs at the end of mitosis. Whether Elys links chromatin with the NE during interphase is unknown. Using DamID-seq, we identified Elys binding sites in Drosophila late embryos and divided them into those associated with nucleoplasmic or with NPC-linked Elys. These Elys binding sites are located within active or inactive chromatin, respectively. Strikingly, Elys knockdown in S2 cells results in peripheral chromatin displacement from the NE, in decondensation of NE-attached chromatin, and in derepression of genes within. It also leads to slightly more compact active chromatin regions. Our findings indicate that NPC-linked Elys, together with the nuclear lamina, anchors peripheral chromatin to the NE, whereas nucleoplasmic Elys decompacts active chromatin.

2024-06-28 | GSE218886 | GEO

Functional interaction of chromatin with nucleoporins in Drosophila

Project description:Nuclear pore complexes (NPCs) mediate transport across the nuclear envelope. In yeast, they have also been proposed to interact with active genes, attracting or retaining them at the nuclear periphery. However, some NPC components (nucleoporins) in higher eukaryotes are also found in the nucleoplasm, with so far unknown function. Therefore, we have functionally distinguished between nucleoporin-chromatin interactions at the NPC and within the nucleoplasm in Drosophila. For this we analyzed genomic interactions of full-length nucleoporins Nup98, Nup50 and Nup62 and nucleoplasmic and NPC-tethered forms of Nup98. We found that nucleoporins predominantly interacted with transcriptionally active genes inside the nucleoplasm. A smaller set of non-active genes interacted with the NPC. We identified a direct role for nucleoplasmic Nup98 in stimulating gene expression, as genes downregulated upon Nup98 depletion were activated upon nucleoplasmic Nup98 overexpression and showed strong nucleoplasmic Nup98 interaction. Thus, nucleoporins stimulate gene expression away from the NPC by interacting with genes inside the nucleoplasm.

2010-03-01 | GSE19307 | GEO

Pre-assembled Nuclear Pores Insert into the Nuclear Envelope During Early Development

Project description:Nuclear Pore Complexes (NPCs) span the nuclear envelope (NE) and mediate nucleocytoplasmic transport. In metazoan oocytes and early embryos, NPCs not only reside within the NE but also at some endoplasmatic reticulum (ER) membrane sheets, termed annulate lamellae (AL). Although a role for AL as NPC storage pools has been discussed, it remains controversial if and how they contribute to the NPC density at the NE. Here we show that AL insert into the NE as the ER feeds rapid nuclear expansion in Drosophila blastoderm embryos. We demonstrate that NPCs within AL resemble pore scaffolds that mature only upon insertion into the NE. We delineate a topological model in which NE openings are critical for AL uptake that nevertheless occurs without compromising the permeability barrier of the NE. We finally show that this unanticipated mode of pore insertion is developmentally regulated and operates prior to gastrulation.

2016-07-12 | PXD004120 | Pride

The nucleoporin Nup50 activates the Ran guanyl-nucleotide exchange factor RCC1 to promote NPC assembly at the end of mitosis

Project description:During mitotic exit, thousands of nuclear pore complexes (NPCs) assemble concomitant with the nuclear envelope to build a transport-competent nucleus. Here, we show that Nup50 plays a crucial role in NPC assembly independent of its well-established function in nuclear transport. RNAi-mediated downregulation in cells or immunodepletion of Nup50 protein in Xenopus egg extracts interferes with NPC assembly. We define a conserved central region of 46 residues in Nup50 that is crucial for Nup153 and MEL28/ELYS binding, and for NPC interaction. Surprisingly, neither NPC interaction nor binding of Nup50 to importin /, the GTPase Ran, or chromatin is crucial for its function in the assembly process. Instead, an N-terminal fragment of Nup50 can stimulate the Ran GTPase guanyl-nucleotide exchange factor RCC1 and NPC assembly, indicating that Nup50 acts via the Ran system in NPC reformation at the end of mitosis. In support of this conclusion, Nup50 mutants defective in RCC1 binding and stimulation cannot replace the wild-type protein in in vitro NPC assembly assays, while excess RCC1 can compensate the loss of Nup50.

2021-11-03 | PXD028701 | Pride

VAPB interacts with phosphorylated ELYS at decondensing chromosomes during mitosis (AP-MS Data)

Project description:ELYS is a nucleoporin that localizes to the nuclear side of the nuclear pore complex (NPC) in interphase cells. In mitosis, it serves as an assembly platform that interacts with chromatin and then with nucleoporin subcomplexes to initiate post-mitotic NPC assembly. Here we identified and characterized ELYS as a major binding partner of the membrane protein VAPB during mitosis. In mitosis, ELYS becomes phosphorylated at many sites, including a predicted FFAT (two phenylalanines in an acidic tract) motif, which is shown to mediate interaction with the MSP (major sperm protein)-domain of VAPB. Phosphorylation-dependent binding of VAPB to ELYS is demonstrated by peptide binding assays and co-immunoprecipitation experiments. In anaphase, the two proteins co-localize to the non-core region of the newly forming nuclear envelope. Depletion of VAPB resulted in prolonged mitosis and slow progression from meta- to anaphase and also to chromosome segregation defects. Together, our results suggest a role of ELYS-VAPB-complexes in recruiting membrane fragments to chromatin.

2024-04-12 | PXD047720 | Pride

A role for the nucleoporin Nup170p in chromatin structure and gene silencing

Project description:Embedded in the nuclear envelope, nuclear pore complexes (NPCs) not only regulate nuclear transport, but also interface with both transcriptionally active euchromatin and largely silenced heterochromatin, as well as the boundaries between these regions. It is unclear what functional role NPCs play in establishing or maintaining these distinct chromatin domains. Here we report that the yeast NPC protein Nup170p interacts with specific regions of the genome containing ribosomal protein and subtelomeric genes. At these locations, Nup170p functions to establish normal nucleosome positioning and as a repressor of transcription. We show that the function of Nup170p in subtelomeric gene silencing is linked to its association with the RSC chromatin-remodeling complex and the silencing factor Sir4p, and that the binding of Nup170p and Sir4p to subtelomeric chromatin is cooperative and necessary for the association of telomeres with the nuclear envelope. Our results establish the NPC as an active participant in the formation of peripheral heterochromatin. This SuperSeries is composed of the SubSeries listed below. Refer to individual Series

2013-02-28 | E-GEOD-36795 | biostudies-arrayexpress

A role for the nucleoporin Nup170p in chromatin structure and gene silencing [Agilent ChIP-chip]

Project description:Embedded in the nuclear envelope, nuclear pore complexes (NPCs) not only regulate nuclear transport, but also interface with both transcriptionally active euchromatin and largely silenced heterochromatin, as well as the boundaries between these regions. It is unclear what functional role NPCs play in establishing or maintaining these distinct chromatin domains. Here we report that the yeast NPC protein Nup170p interacts with specific regions of the genome containing ribosomal protein and subtelomeric genes. At these locations, Nup170p functions to establish normal nucleosome positioning and as a repressor of transcription. We show that the function of Nup170p in subtelomeric gene silencing is linked to its association with the RSC chromatin-remodeling complex and the silencing factor Sir4p, and that the binding of Nup170p and Sir4p to subtelomeric chromatin is cooperative and necessary for the association of telomeres with the nuclear envelope. Our results establish the NPC as an active participant in the formation of peripheral heterochromatin. The genome-wide localization profiles of Nup170p and Nup157p were determined by chromatin immunoprecipitation and DNA microarray analysis using agilent whole genome Saccharomyces cerevisiae arrays. In addition, the localization profile of Nup170p was determined in sir4∆ and yku70∆ strains.

2013-02-28 | E-GEOD-36794 | biostudies-arrayexpress

Docking a flexible basket onto the core of the nuclear pore complex

Project description:The nuclear basket attaches to the nucleoplasmic side of the nuclear pore complex (NPC), coupling transcription to mRNA quality control and export. The basket expands the functional repertoire of a subset of NPCs in S. cerevisiae by drawing a unique RNA/protein interactome. Yet, how the basket docks onto the NPC core remains unknown. By integrating AlphaFold-powered interaction screens, electron microscopy and membrane-templated reconstitution, we uncovered a membrane-anchored tripartite junction between basket and NPC core. The basket subunit Nup60 harbours three adjacent short linear motifs (SLiMs) which connect Mlp1, a parallel homodimer consisting of coiled-coil segments interrupted by flexible hinges, and the Nup85 subunit of the Y-complex. We reconstituted the Y-complex•Nup60•Mlp1 assembly on a synthetic membrane and validated the protein interfaces in vivo. Our study explains how a SLiM-based protein junction can substantially reshape NPC structure and function, advancing our understanding of compositional and conformational NPC heterogeneity.

2024-07-11 | PXD052015 | Pride

SUMO protease and proteasome recruitment at the nuclear periphery differently affect replication dynamics at arrested forks.

Project description:Nuclear pores complexes (NPCs) are genome organizers, defining a particular nuclear compartment enriched for SUMO protease and proteasome activities, and act as docking sites for DNA repair. In fission yeast, the anchorage of perturbed replication forks to NPCs is an integral part of the recombination-dependent replication restart mechanism (RDR) that resumes DNA synthesis at terminally dysfunctional forks. By mapping DNA polymerase usage, we report that SUMO protease Ulp1-associated NPCs ensure efficient initiation of restarted DNA synthesis, whereas proteasome-associated NPCs sustain the speed of restarted DNA polymerase. In contrast to Ulp1, this last function occurs independently of SUMO chains formation. By analyzing the role of the nuclear basket, the nucleoplasmic extension of the NPC, we reveal that the activities of Ulp1 and the proteasome cannot compensate for each other and affect the dynamics of RDR in distinct ways. Our work probes the mechanisms by which the NPC environment ensures optimal RDR.

2023-11-13 | GSE247371 | GEO

A role for the nucleoporin Nup170p in chromatin structure and gene silencing [Agilent microarrays]

2013-02-28 | GSE36793 | GEO