Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Nuclear speckles as a key regulator for the 3D genome organization [HiC]

ABSTRACT: The nuclei of eukaryotes contain various higher-order chromatin architectures and nuclear bodies (NBs), which are critical for proper nuclear functions. By using mouse hepatocytes as the model, we knocked-down SRRM2, a core protein component scaffolding NSs, and performed Hi-C experiments to examine genome-wide chromatin interactions. We found that Srrm2 depletion disrupted the NSs and changes expression of about 1,000 genes. The intra-chromosomal interactions were decreased in type A (active) compartments and increased in type B (repressive) compartments. Furthermore, upon Srrm2 knockdown, the insulation of TADs was decreased specifically in active compartments, and the most significant reduction was found in the A1 sub-compartments. We showed that disruption of NSs by Srrm2 knockdown led to a global decrease of chromatin interactions in active compartments, indicating critical functions of NSs in the organization of the 3D genome.

ORGANISM(S): Mus musculus

PROVIDER: GSE131463 | GEO | 2019/06/30

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Nuclear speckles as a key regulator for the 3D genome organization [RNA-Seq]

Project description:The nuclei of eukaryotes contain various higher-order chromatin architectures and nuclear bodies (NBs), which are critical for proper nuclear functions. By using mouse hepatocytes as the model, we knocked-down SRRM2, a core protein component scaffolding NSs, and performed Hi-C experiments to examine genome-wide chromatin interactions. We found that Srrm2 depletion disrupted the NSs and changes expression of about 1,000 genes. The intra-chromosomal interactions were decreased in type A (active) compartments and increased in type B (repressive) compartments. Furthermore, upon Srrm2 knockdown, the insulation of TADs was decreased specifically in active compartments, and the most significant reduction was found in the A1 sub-compartments. We showed that disruption of NSs by Srrm2 knockdown led to a global decrease of chromatin interactions in active compartments, indicating critical functions of NSs in the organization of the 3D genome.

2019-06-30 | GSE130805 | GEO

SRRM2 Phase Separation Drives Assembly of Nuclear Speckle Subcompartments

Project description:Nuclear speckles (NSs) are nuclear biomolecular condensates that are postulated to arise through liquid-liquid phase separation (LLPS), although the detailed underlying forces driving NS formation remain elusive. SRRM2 and SON are 2 non-redundant scaffold proteins for NSs. How each individual protein governs assembly of NS protein network and the functional relationship between SRRM2 and SON are largely unknown. Here, we uncover immiscible multiphase of SRRM2 and SON within NSs. SRRM2 and SON are functionally independent, specifically regulating alternative splicing of subsets of mRNA targets, respectively. We further uncover that SRRM2 forms multicomponent liquid phase in cells to drive NS subcompartmentalization, which is reliant on homotypic interaction and heterotypic non-selective protein-RNA complex coacervation-driven multicomponent LLPS. SRRM2 RS domains form high-order oligomers, and can be replaced by oligomerizable synthetic modules, the serine residues within the RS domains, however, play an irreplaceable role in fine-tuning the liquidity of NSs.

2024-01-31 | GSE242898 | GEO

TAF2 condensation in nuclear speckles links basal transcription factor TFIID to RNA splicing [CUT&RUN]

Project description:TFIID is an essential basal transcription factor, crucial for RNA polymerase II (pol II) promoter recognition and transcription initiation. The TFIID complex consists of the TATA-binding protein (TBP) and 13 TBP-associated factors (TAFs) that contain intrinsically disordered regions (IDRs) with currently unknown functions. Here, we show that a conserved IDR drives TAF2 condensation in nuclear speckles, independently of other TFIID subunits. Quantitative mass spectrometry analyses reveal that the TAF2 IDR specifically interacts with the nuclear speckle and spliceosome-associated protein SRRM2. Consequently, TAF2 recruits SRRM2 to TFIID to form non-canonical TFIID-SRRM2 complexes. Reduced SRRM2 recruitment elicits alternative splicing events in RNAs coding for proteins involved in transcription and transmembrane transport. Further, genome-wide binding analyses suggest TAF2 shuttling between nuclear speckles and pol II promoters. This study identifies an IDR of the basal transcription machinery as a molecular guide for protein partitioning into nuclear compartments, controlling protein complex composition and pre-mRNA splicing.

2024-02-06 | GSE254080 | GEO

TAF2 condensation in nuclear speckles links basal transcription factor TFIID to RNA splicing [RNA-Seq]

2024-02-06 | GSE254060 | GEO

Platform-based gene regulation by an endoderm-specific lncRNA via stabilizing nuclear speckles

Project description:Nuclear speckles (NSs), one of the key non-membrane nuclear bodies, participate in transcription, RNA processing, and chromatin organization, yet their precise functions and mechanisms in vivo remain elusive. Here we show that Falcor, an endoderm-specific long non-coding RNA (lncRNA), is necessary and sufficient for maintaining structural integrity of NSs in mouse liver cells. Disruption and reinstatement of NSs by Falcor coordinately regulate more than one thousand genes, including those related to metabolic processes. Falcor locates in the core of NSs, and interacts with Zinc finger CCCH domain-containing protein 11A (ZC3H11A), thereby facilitating phase separation to maintain NSs' structure. Furthermore, specific knockout of Falcor in the mouse liver uncovered its pivotal role in governing metabolic homeostasis, and its absence affords protection against diet-induced liver steatosis, obesity, and metabolic disorders. Collectively, our study demonstrated essential roles of Falcor in NSs maintenance and regulating metabolic homeostasis, which imply the importance of lineage-specific lncRNAs in “platform-based” gene regulation via NSs during pathophysiological processes.

2024-05-13 | GSE267072 | GEO

TAF2 condensation in nuclear speckles links basal transcription factor TFIID to RNA splicing

Project description:TFIID is an essential eukaryotic transcription factor, which is required for RNA polymerase II promoter recognition and activation. As a multiprotein complex, TFIID contains several intrinsically disordered regions (IDRs), but the functions of these IDRs are unknown. Here, we show that a conserved IDR drives the TFIID subunit TAF2 to nuclear speckles, where it forms biomolecular condensates, separate from the TFIID complex. Quantitative mass spectrometry analyses reveal that the TAF2 IDR is required for the interaction with the nuclear speckle and spliceosome-associated protein SRRM2, which is thereby recruited to TFIID. The formation of SRRM2-free TFIID complexes elicits a set of unique alternative splicing events. These include events in RNAs coding for proteins involved in transcription and transmembrane transport. Together, these data identify an IDR of the basal transcription machinery as a molecular switch between nuclear compartments to control protein complex composition and pre-mRNA splicing.

2024-04-26 | PXD049117 | Pride

PML2‐mediated thread‐like nuclear bodies mark late senescence in Hutchinson–Gilford progeria syndrome [RNA-seq]

Project description:Regular nuclear structure is critical for genome maintenance and proper gene expression, disorder of which has a causal role in aging. Accumulation of Progerin in Hutchinson-Gilford progeria syndrome (HGPS) disrupts the integrity of nuclear lamina and causes nuclear structure abnormalities, leading to premature aging. However, the nuclear structure/function relationships in HGPS cells have not been well addressed, and roles of nuclear sub-compartments for HGPS pathogenesis are rarely reported. Here, evidence reveals that classical dot-like PML nuclear bodies (PML NBs) are reorganized into thread-like morphology in HGPS cells, and these irregular NBs are strongly associated with cell senescence. We demonstrate that farnesylated Progerin interacts with PML isoform 2 specifically, which accounts for the formation of thread-like PML NBs. Moreover, our findings uncover that irregular PML NBs perturb NBs-associated DNA repair and gene transcription, thereby promoting HGPS cell senescence. Thus, our work helps to clarify the roles of nuclear structure and sub-compartments such as PML NBs in cell aging, and evidence presented in this study strongly support that thread-like PML NBs could be a novel biomarker of human cell senescence.

2019-09-10 | GSE137083 | GEO

PML2‐mediated thread‐like nuclear bodies mark late senescence in Hutchinson–Gilford progeria syndrome [ChIP-seq]

2019-09-10 | GSE137084 | GEO

Interplay between PML NBs and HIRA for H3.3 deposition on transcriptionally active interferon-stimulated genes

Project description:Promyelocytic Leukemia Nuclear Bodies (PML NBs) are nuclear membrane-less organelles physically associated with chromatin underscoring their crucial role in genome function. The H3.3 histone chaperone complex HIRA accumulates in PML NBs upon senescence, viral infection or IFN-I treatment in primary cells. Yet, the molecular mechanisms of this partitioning and its function in regulating histone dynamics have remained elusive. Here, by using specific siRNAs and protein Affimers, we identify intermolecular SUMO-SIM interactions as an essential mechanism for HIRA recruitment in PML NBs. In addition, we demonstrate that HIRA localization in the nuclear bodies is intimately linked to the presence of a soluble pool of H3.3-H4 dimers inside PML NBs, that is not found in cancer cells. Transcription inhibition prevents HIRA accumulation in PML NBs underscoring the importance of transcriptional activity to drive HIRA through PML NBs. Finally, in the context of inflammatory responses, HIRA and PML are necessary for the prolonged H3.3 deposition at the transcriptional end sites of interferon-stimulated genes (ISGs), well beyond the peak of transcription. We thus propose that HIRA partitioning in PML NBs is essential to regulate H3.3 deposition on transcriptionally active regions.

2023-05-25 | GSE233298 | GEO

Interplay between PML NBs and HIRA for H3.3 deposition on transcriptionally active interferon-stimulated genes

2023-05-30 | GSE186937 | GEO