Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Phase separation and stress granule association of SARS-CoV-2 Nucleocapsid protein

ABSTRACT: The current work identified the protein interactors of SARS-CoV-2 Nucleocapsid RNA binding protein (NCAP or N protein) in lung cancer A-549 cells, using a co-immunoprecipitation strategy, which is coupled with SILAC-based mass spec. A significant proportion of the identified NCAP interacting proteins included stress granule (SG) and immunoregulators. SG nucleator G3BP1 showed specific interaction wit NCAP in unstressed and oxidative- or heat-stressed cells. Following stress treatment, NCAP showed enhanced association with SGs. Recombinant NCAP exhibited in vitro liquid-liquid phase separation (LLPS)to form liquid droplets. RNA stimulated NCAP to develop droplets in vitro and SG assembly in cells, and RNase A treatment completely blocked both of these functions. An RNA intercalating mitoxantrone disrupted NCAP assembly in SGs invitro and in cells. This study provides insight into the biological processes and biophysical properties of the SARS-CoV-2 NCAP and identifies a candidate way to target this protein.

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Epithelial Cell, Cell Culture

DISEASE(S): Lung Carcinoma

SUBMITTER: Syam Prakash Somasekharan

LAB HEAD: Dr. Syam Prakash Somasekharan

PROVIDER: PXD023989 | Pride | 2021-11-25

REPOSITORIES: Pride

ACCESS DATA

Json Xml

Similar Datasets

G3BP1-linked mRNA partitioning supports selective protein synthesis in response to oxidative stress

Project description:Cells limit energy-consuming mRNA translation during stress to maintain metabolic homeostasis. Sequestration of mRNAs by RNA binding proteins (RBPs) into stress granules (SGs) reduces translation, but it remains unclear whether SGs also function in partitioning of specific transcripts to polysomes (PSs) to guide selective translation and stress-adaptation in cancer. Transcripts enriched in PSs, defined by polysome fractionation and RNAseq, were compared with mRNAs complexed with the SG-nucleator protein, G3BP1, defined by spatially-restricted enzymatic tagging. Short-term oxidative stress profoundly altered mRNA translation by promoting selective enrichment of transcripts within SGs or PSs. G3BP1 participates in this compartmentalisation by sequestering transcripts in SGs. Under stress, G3BP1-bound transcripts are PS-depleted and encode proteins involved in mRNA translation, pro-apoptosis, and mitochondrial function. In contrast, specific PS-enriched transcripts disassociate from G3BP1 under stress to encode proteins involved in diverse cellular cytoprotective pathways. Therefore, G3BP1 partitioning guides selective translation to support stress adaptation and cell survival.

2020-04-30 | PXD015491 | Pride

SILAC & LC-MSMS in total cell extracts or in the secretome of POU5F1B- vs. GFP-overexpressing SW480 cells

Project description:The treatment of colorectal cancer (CRC) is an unmet medical need in absence of early diagnosis. Here, upon characterizing cancer-specific transposable element-driven transpochimeric gene transcripts (TcGTs) produced by this tumor, we found that expression of the hominid-restricted retrogene POU5F1B through aberrant activation of a primate-specific endogenous retroviral promoter is a strong negative prognostic CRC biomarker. Correlating this observation, we could demonstrate that POU5F1B fosters the proliferation and metastatic potential of CRC cells. We further determined that POU5F1B, in spite of its phylogenetic relationship with the POU5F1/OCT4 transcription factor, is a membrane-enriched protein that associates with protein kinases and known targets or interactors as well as with cytoskeleton-related molecules, and induces intracellular signaling events and the release of trans-acting factors involved in cell growth and cell adhesion. As POU5F1B is an apparently non-essential gene only lowly expressed in normal tissues, and as POU5F1B-containing TcGTs are detected in other tumors besides CRC, our data provide interesting leads for the development of cancer therapies.

2022-10-14 | PXD028035 | Pride

SILAC & LC-MSMS in total cell extracts or in the secretome of sh-scramble vs. shRNA3 & shRNA5 LS1034 cells

2022-10-14 | PXD028036 | Pride

Chromosomal instability adaptation dependencies confer unique targetable vulnerabilities in therapy refractory lethal prostate cancer

Project description:Chromosomal instability (CIN), an ongoing rate of chromosome missegregation during mitosis, is a defining feature of cancer. However, high chromosomal aberrations are detrimental for cell fitness. Here we investigated mechanisms allowing lethal prostate cancer (PCa) to tolerate and survive increasing CIN. Transcriptomic and proteomic analysis of patient datasets and experimental models showed a concomitant increase of CIN and cell division fidelity kinases in lethal PCa. Functional studies identified MASTL as a key kinase to which therapy-resistant PCa cells become addicted to restrain lethal CIN and ensure survival. Combined analysis of transcription factors increased in high CIN PCa patient datasets with detailed promoter analysis identified that MASTL expression is regulated by the Androgen Receptor variant 7 (AR-V7) and E2F7. Finally, targeting MASTL addiction vulnerability in vivo using the small molecule inhibitor GKI-1, improves survival of pre-clinical models. These findings provide proof-of-concept for exploiting CIN levels as a therapeutic approach in cancer.

2023-01-14 | PXD028271 | Pride

SILAC-based quantitative proteomics using mass spectrometry identifies BAG-6 mediated changes in the subproteome degraded by endosomal microautophagy (eMI).

Project description:To identify the subproteome degraded by endosomal microautophagy (eMI) in a Bag6-dependent manner, we compared the proteome of late endosomal compartments LE/MVBs isolated from control(wild type) and Bag6(-) cells using SILAC labeling and quantitative proteomics.

2024-01-26 | PXD046760 | Pride

CHD7- and HDAC1/2-dependent chromatin remodeling activities cooperate to promote DNA double-strand break repair

Project description:The DNA double-strand break (DSB) response is a multi-step process that requires chromatin reorganization at each stage. 53BP1 is a nodal point in this response as it directs chromatin-based DSB repair. However, how chromatin reorganization impacts DSB repair upstream of 53BP1 is not fully understood. Here we reveal that Chromodomain Helicase DNA Binding Protein 7 (CHD7) rapidly recruits to damaged chromatin in a poly(ADP-ribose) polymerase 1 (PARP1)-dependent manner. CHD7 facilitates chromatin relaxation and the loading of canonical non-homologous end-joining (cNHEJ) factors, while restraining 53BP1 accumulation at DSBs. Moreover, CHD7 physically associates with HDAC1/2, thereby recruiting this complex to DNA breaks independently of its chromatin remodeling activity. HDAC1/2 promote histone H4 de-acetylation and chromatin re-compaction to prevent supraphysiological retention of cNHEJ factors at DBSs. Thus, the cooperation between distinct yet coordinated chromatin remodeling activities driven by CHD7 and HDAC1/2 ensures proper assembly dynamics of the cNHEJ machinery and efficient DSB repair.

2020-08-28 | PXD014339 | Pride

SMC Complexes Are Guarded by the SUMO Protease Ulp2 Against SUMO-Chain-Mediated Turnover

Project description:Structural maintenance of chromosomes (SMC) complexes, cohesin, condensin and Smc5/6, are essential for viability and participate in multiple processes, including sister chromatid cohesion, chromosome condensation, and DNA repair. Here we show that SUMO chains target all three SMC complexes and are antagonized by the SUMO protease Ulp2 to prevent their turnover. We uncover that the essential role of the cohesin-associated subunit Pds5 is to counteract SUMO chains jointly with Ulp2. Importantly, fusion of Ulp2 to kleisin Scc1 supports viability of PDS5 null cells and protects cohesin from proteasomal degradation mediated by the SUMO-targeted ubiquitin ligase Slx5/Slx8. The lethality of PDS5 deleted cells can also be bypassed by simultaneous loss of the PCNA unloader, Elg1, and the cohesin releaser, Wpl1, but only when Ulp2 is functional. Condensin and Smc5/6 complex are similarly guarded by Ulp2 against unscheduled SUMO-chain assembly, which we propose to time the availability of SMC complexes on chromatin.

2021-08-05 | PXD022717 | Pride

Ubiquitin ligase WWP2 targets RNA polymerase II in a DNA-PK-dependent transcription shutoff circuitry for DNA repair

Project description:DNA double-strand breaks (DSBs) at RNA polymerase II (RNAPII)-transcribed genes lead to inhibition of transcription. DNA protein kinase (DNA-PK) complex plays a pivotal role in transcription inhibition at DSBs by stimulating proteasome-dependent eviction of RNAPII at these lesions. How DNA-PK triggers RNAPII eviction to inhibit transcription at DSBs remained unclear. Here we show that the HECT E3 ubiquitin ligase WWP2 associates with components of the DNA-PK and RNAPII complexes and is recruited to DSBs at RNAPII-transcribed genes. In response to DSBs, WWP2 targets the RNAPII subunit RPB1 for K48-linked ubiquitylation, thereby driving DNA-PK- and proteasome-dependent eviction of RNAPII. The lack of WWP2 or expression of non-ubiquitylatable RPB1 abrogates the loading of Non-Homologous End-Joining (NHEJ) factors, including DNA-PK and XRCC4/DNA ligase IV, and impairs DSB repair. These findings suggest that WWP2 operates in a DNA-PK-dependent shut-off circuitry for RNAPII clearance that promotes DSB repair by protecting the NHEJ machinery from collision with the transcription machinery.

2019-03-29 | PXD012606 | Pride

Identification of heat induced, RNF4 regulated ubiquitylation sites

Project description:Exposure of cells to heat or oxidative stress causes misfolding of proteins. To avoid toxic protein aggregation, cells have evolved nuclear and cytosolic protein quality control (PQC) systems. In response to proteotoxic stress cells also limit protein synthesis by triggering transient storage of mRNAs and RNA binding proteins (RBPs) in cytosolic stress granules (SGs). We demonstrate that the SUMO-targeted ubiquitin ligase (StUbL) pathway, which is part of the nuclear proteostasis network, regulates SG dynamics. We provide evidence that inactivation of SUMO deconjugases under proteotoxic stress initiates SUMO-primed, RNF4-dependent ubiquitylation of RBPs that typically condense into SGs. Impairment of SUMO-primed ubiquitylation drastically delays SG resolution upon stress release. Importantly, the StUbL system regulates compartmentalization of an amyotrophic lateral sclerosis (ALS)-associated mutant of FUS in SGs. We propose that the StUbL system functions as surveillance pathway for aggregation-prone RBPs in the nucleus thereby linking the nuclear and cytosolic axis of proteotoxic stress response. Toidentify heat induced, RNF4 regulated ubiquitylation sites we performed an unbiased SILAC-based mass-spectrometry screen comparing heat-induced ubiquitylation in control and RNF4 depleted cells.

2023-06-30 | PXD017887 | Pride

Loss of ZBTB24, a novel non-homologous end-joining protein, impairs class-switch recombination in ICF syndrome

Project description:The autosomal recessive immunodeficiency, centromeric instability and facial anomalies (ICF) syndrome is a genetically heterogeneous disorder. Despite recent successes in the identification of the underlying gene defects, it is currently unclear how mutations in any of the four known ICF genes cause a primary immunodeficiency. Here we demonstrate that loss of ZBTB24 in B cells from ICF2 patients impairs non-homologous end-joining (NHEJ) during immunoglobulin class-switch recombination and consequently impairs immunoglobulin production and subtype balance. Mechanistically, we found that ZBTB24 associates with poly(ADP-ribose) polymerase 1 (PARP1) and stimulates auto-poly(ADP-ribosyl)ation of this enzyme. The zinc finger in ZBTB24 binds PARP1-associated poly(ADP-ribose) chains and mediates the PARP1-dependent recruitment of ZBTB24 to DNA breaks. Moreover, by binding to poly(ADP-ribose) chains ZBTB24 protects these moieties from degradation by poly(ADP-ribose) glycohydrolase (PARG). This enhances the poly(ADP-ribose)-dependent interaction between PARP1 and the LIG4/XRCC4 NHEJ complex and promotes NHEJ by facilitating the assembly of this repair complex at DNA breaks. Thus, we uncover ZBTB24 as a regulator of PARP1-dependent NHEJ and class-switch recombination, providing a molecular basis for the immunodeficiency in ICF syndrome.

2020-08-19 | PXD014741 | Pride

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

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