Browse
Submit Data
Databases
API
Help

Dataset Information

14 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Nucleocytoplasmic transport blockage by SV40 peptide-modified gold nanoparticles induces cellular autophagy.

ABSTRACT: Gold nanoparticles modified with the nuclear localization signal from simian virus 40 large T antigen (GNP-PEG/SV40) accumulate on the cytoplasmic side of the nuclear membrane in HeLa cells. Accumulation of GNP-PEG/SV40 around the nucleus blocks nucleocytoplasmic transport and prevents RNA export and nuclear shuttling of signaling proteins. This long-term blockage of nucleocytoplasmic transport results in cell death. This cell death is not caused by apoptosis or necrosis because caspases 3 and 9 are not activated, and the expression of annexin V/propidium iodide is not enhanced in HeLa cells after treatment. Using transmission electron microscopy, autophagosomes and autolysosomes were seen to appear after 72 hours of treatment with GNP-PEG/SV40. Increasing levels of enhanced green fluorescent protein-microtubule-associated protein 1 light chain 3 (EGFP-LC3)-positive punctate and LC3-II confirmed GNP-PEG/SV40-induced autophagy. In SiHa cells, treatment did not induce accumulation of GNP-PEG/SV40 around the nucleus and autophagy. Treating cells with wheat germ agglutinin, a nuclear pore complex inhibitor, induced autophagy in both HeLa and SiHa cells. GNP-PEG/SV40-induced autophagy plays a role in cell death, not survival, and virus-mediated small hairpin RNA silencing of Beclin-1 attenuates cell death. Taken together, the results indicate that long-term blockade of nucleocytoplasmic transport results in autophagic cell death.

SUBMITTER: Tsai TL

PROVIDER: S-EPMC3469097 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Structural basis for Sarbecovirus ORF6 mediated blockage of nucleocytoplasmic transport.

Project description:The emergence of heavily mutated SARS-CoV-2 variants of concern (VOCs) place the international community on high alert. In addition to numerous mutations that map in the spike protein of VOCs, expression of the viral accessory proteins ORF6 and ORF9b also elevate; both are potent interferon antagonists. Here, we present the crystal structures of Rae1-Nup98 in complex with the C-terminal tails (CTT) of SARS-CoV-2 and SARS-CoV ORF6 to 2.85 Å and 2.39 Å resolution, respectively. An invariant methionine (M) 58 residue of ORF6 CTT extends its side chain into a hydrophobic cavity in the Rae1 mRNA binding groove, resembling a bolt-fitting-hole; acidic residues flanking M58 form salt-bridges with Rae1. Our mutagenesis studies identify key residues of ORF6 important for its interaction with Rae1-Nup98 in vitro and in cells, of which M58 is irreplaceable. Furthermore, we show that ORF6-mediated blockade of mRNA and STAT1 nucleocytoplasmic transport correlate with the binding affinity between ORF6 and Rae1-Nup98. Finally, binding of ORF6 to Rae1-Nup98 is linked to ORF6-induced interferon antagonism. Taken together, this study reveals the molecular basis for the antagonistic function of Sarbecovirus ORF6, and implies a strategy of using ORF6 CTT-derived peptides for immunosuppressive drug development.

| S-EPMC9376891 | biostudies-literature

Oligonucleotide loading determines cellular uptake of DNA-modified gold nanoparticles.

Project description:The cellular internalization of oligonucleotide-modified nanoparticles is investigated. Uptake is dependent on the density of the oligonucleotide loading on the surface of the particles, where higher densities lead to greater uptake. Densely functionalized nanoparticles adsorb a large number of proteins on the nanoparticle surface. Nanoparticle uptake is greatest where a large number of proteins are associated with the particle.

| S-EPMC8585332 | biostudies-literature

Quantitative Nucleocytoplasmic Transport Assays in Cellular Models of Neurodegeneration.

Project description:Nucleocytoplasmic transport deficits are suggested to play a role in neurodegenerative disorders, including amyotrophic lateral sclerosis (ALS). Given the importance and complexity of this process, understanding when these aberrations occur and which pathways are involved is of great importance. Here, we make use of CRISPR-Cas9 technology to design cell lines stably expressing fluorophore proteins shuttling between the nucleus and cytoplasm by karyopherins of choice. To validate this protocol, we measured an ALS-associated nucleocytoplasmic transport pathway in the presence of the disease-associated peptide poly-PR. This technique allows measuring a particular active nucleocytoplasmic transport pathway in intact cells in a neurodegenerative disease-associated context. Moreover, these experiments can be performed without the need for expensive equipment and have the potential to be upscaled for high-throughput screening purposes.

| S-EPMC7842572 | biostudies-literature

Cellular Stress Induces Nucleocytoplasmic Transport Deficits Independent of Stress Granules.

Project description:Stress granules are non-membrane bound granules temporarily forming in the cytoplasm in response to stress. Proteins of the nucleocytoplasmic transport machinery were found in these stress granules and it was suggested that stress granules contribute to the nucleocytoplasmic transport defects in several neurodegenerative disorders, including amyotrophic lateral sclerosis (ALS). The aim of this study was to investigate whether there is a causal link between stress granule formation and nucleocytoplasmic transport deficits. Therefore, we uncoupled stress granule formation from cellular stress while studying nuclear import. This was carried out by preventing cells from assembling stress granules despite being subjected to cellular stress either by knocking down both G3BP1 and G3BP2 or by pharmacologically inhibiting stress granule formation. Conversely, we induced stress granules by overexpressing G3BP1 in the absence of cellular stress. In both conditions, nuclear import was not affected demonstrating that stress granule formation is not a direct cause of stress-induced nucleocytoplasmic transport deficits.

| S-EPMC9138870 | biostudies-literature

Global genetic impact of surface-modified gold nanoparticles on two model human cell lines

Project description:Gold nanoparticles (Au NPs) are uniquely suited for various biomedical applications due to the combination of their optical properties with their easily functionalized surfaces. The Au NP surface can be tailored to improve biocompatibility while also attaching targeting ligands or drugs. However, information on how these tailored surface chemistries may affect cell gene expression is scarce. Using two model human cells line, human dermal fibroblasts and prostate cancer cells, microarray experiments measured gene expression over 27,000 human genes. Each of the cell lines was exposed to four related types of surface-modified Au NPs at two different concentrations, and the microarray data was analyzed by weighted gene correlation network analysis and gene functional annotation. Au NPs were shown to affect genes associated with a variety of cellular functions, and surface charge and chemistry were linked with the types of parthways changed and the degree of which those changes occured.

2014-10-01 | GSE56432 | GEO

Nucleocytoplasmic transport rates are regulated by cellular processes that modulate GTP availability.

Project description:Nucleocytoplasmic transport (NCT), the facilitated diffusion of cargo molecules between the nucleus and cytoplasm through nuclear pore complexes (NPCs), enables numerous fundamental eukaryotic cellular processes. Ran GTPase uses cellular energy in the direct form of GTP to create a gradient across the nuclear envelope (NE) that drives the majority of NCT. We report here that changes in GTP availability resulting from altered cellular physiology modulate the rate of NCT, as monitored using synthetic and natural cargo, and the dynamics of Ran itself. Cell migration, cell spreading and/or modulation of the cytoskeleton or its connection to the nucleus alter GTP availability and thus rates of NCT, regulating RNA export and protein synthesis. These findings support a model in which changes in cellular physiology that alter GTP availability can regulate the rate of NCT, impacting fundamental cellular processes that extensively utilize NCT.

| S-EPMC10793428 | biostudies-literature

STRT RNAseq of THP-1 monocytic cells exposed to surface modified-gold nanoparticles

Project description:Transcriptome comparison to assess the responses of human monocytic cells (THP-1) to gold-nanoparticles (Au-NPs) of two different diameter sizes (5 or 20 nm) with different surface functional groups, i.e., alkylammonium bromide, alkyl sodium carboxylate, or poly(ethylene glycol) (PEG)-terminated thiolate Au-NPs.

2019-06-04 | E-MTAB-7093 | biostudies-arrayexpress

Thermal Transport through Polymer-Linked Gold Nanoparticles.

Project description:Polymer-nanoparticle networks have potential applications in molecular electronics and nanophononics. In this work, we use all-atom molecular dynamics to reveal the fundamental mechanisms of thermal transport in polymer-linked gold nanoparticle (AuNP) dimers at the molecular level. Attachment of the polymers to AuNPs of varying sizes allows the determination of effects from the flexibility of the chains when their ends are not held fixed. We report heat conductance (G) values for six polymers-viz. polyethylene, poly(p-phenylene), polyacene, polyacetylene, polythiophene, and poly(3,4-ethylenedioxythiophene)-that represent a broad range of stiffness. We address the multimode effects of polymer type, AuNP size, polymer chain length, polymer conformation, system temperature, and number of linking polymers on G. The combination of the mechanisms for phonon boundary scattering and intrinsic phonon scattering has a strong effect on G. We find that the values of G are larger for conjugated polymers because of the stiffness in their backbones. They are also larger in the low-temperature region for all polymers owing to the quenching of segmental rotations at low temperature. Our simulations also suggest that the total G is additive as the number of linking polymers in the AuNP dimer increases from 1 to 2 to 3.

| S-EPMC9639611 | biostudies-literature

Global genetic impact of surface-modified gold nanoparticles on two model human cell lines

2014-10-01 | E-GEOD-56432 | biostudies-arrayexpress

Reversibility in nucleocytoplasmic transport.

Project description:Nucleocytoplasmic exchange of proteins and RNAs is mediated by receptors that usher their cargo through the nuclear pores. Peptide localization signals on each cargo determine the receptors with which it will interact. Those interactions are normally regulated by the small GTPase Ran. Hydrolysis of GTP provides the chemical energy required to create a bona fide thermodynamic pump that selectively and directionally accumulates its substrates across the nuclear envelope. A common perception is that cargo delivery is irreversible, e.g., a protein imported to the nucleus does not return to the cytoplasm except perhaps via a specific export receptor. Quantitative measurements using cell-free nuclei reconstituted in Xenopus egg extract show that nuclear accumulation follows first-order kinetics and reaches steady state at a level that follows a Michaelis-Menten function of the cytoplasmic cargo concentration. This saturation suggests that receptor-mediated translocation across the nuclear pore occurs bidirectionally. The reversibility of accumulation was demonstrated directly by exchange of the cytosolic medium and by fluorescence recovery after photobleaching. Based on our results, we offer a simple biophysical model that predicts the observed behavior. A far-reaching consequence is that the nuclear localization signal dictates the fate of a protein population rather than that of the individual molecules that bear it, which remain free to shuttle back and forth. This implies an open communication between the nucleus and cytoplasm and a ubiquitous mechanism for signaling in both directions.

| S-EPMC1937537 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data