Nuclear IQGAP1 promotes gastric cancer cell growth by altering the splicing of a cell-cycle regulon in co-operation with hnRNPM
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE146283 | GEO | 2021/09/09
REPOSITORIES: GEO
Similar Datasets
Project description:A constant communication between mitochondria and nucleus ensures cellular homeostasis and adaptation to mitochondrial stress. Anterograde regulatory pathways involving a large number of nuclear-encoded proteins control mitochondrial biogenesis and functions. Such functions are deregulated in cancer, resulting in proliferative advantages for cancer cells, aggressive disease and therapeutic resistance. Transcriptional networks controlling the nuclear-encoded mitochondrial genes are known, however alternative splicing (AS) regulation has not been implicated in this communication. Here, we show that IQGAP1, a scaffold protein that regulates AS of distinct gene subsets in gastric cancer cells, participates in AS regulation that strongly affects mitochondrial respiration. Combined proteomic and RNA-seq analyses of IQGAP1 KO and parental cells show that IQGAP1 KO alters a specific AS event of the mitochondrial respiratory chain complex I (CI) subunit NDUFS4 and downregulates a subset of CI subunits. In IQGAP1 KO cells, CI intermediates accumulate resembling assembly deficiencies observed in patients with Leigh syndrome bearing NDUFS4 mutations. Mitochondrial CI activity is significantly lower in KO compared to parental cells, while exogenous expression of IQGAP1 reverses mitochondrial defects of IQGAP1 KO cells. Our work sheds light to a novel facet of IQGAP1 in mitochondrial quality control that involves fine-tuning of CI activity through AS regulation in gastric cancer.
2023-08-04 | PXD038314 | Pride
Project description:A constant communication between mitochondria and nucleus ensures cellular homeostasis and adaptation to mitochondrial stress. Anterograde regulatory pathways involving a large number of nuclear-encoded proteins control mitochondrial biogenesis and functions. Such functions are deregulated in cancer, resulting in proliferative advantages for cancer cells, aggressive disease and therapeutic resistance. Transcriptional networks controlling the nuclear-encoded mitochondrial genes are known, however alternative splicing (AS) regulation has not been implicated in this communication. Here, we show that IQGAP1, a scaffold protein that regulates AS of distinct gene subsets in gastric cancer cells, participates in AS regulation that strongly affects mitochondrial respiration. Combined proteomic and RNA-seq analyses of IQGAP1 KO and parental cells show that IQGAP1 KO alters a specific AS event of the mitochondrial respiratory chain complex I (CI) subunit NDUFS4 and downregulates a subset of CI subunits. In IQGAP1 KO cells, CI intermediates accumulate resembling assembly deficiencies observed in patients with Leigh syndrome bearing NDUFS4 mutations. Mitochondrial CI activity is significantly lower in KO compared to parental cells, while exogenous expression of IQGAP1 reverses mitochondrial defects of IQGAP1 KO cells. Our work sheds light to a novel facet of IQGAP1 in mitochondrial quality control that involves fine-tuning of CI activity through AS regulation in gastric cancer.
2023-08-04 | PXD038331 | Pride
Project description:A constant communication between mitochondria and nucleus ensures cellular homeostasis and adaptation to mitochondrial stress. Anterograde regulatory pathways involving a large number of nuclear-encoded proteins control mitochondrial biogenesis and functions. Such functions are deregulated in cancer, resulting in proliferative advantages for cancer cells, aggressive disease and therapeutic resistance. Transcriptional networks controlling the nuclear-encoded mitochondrial genes are known, however alternative splicing (AS) regulation has not been implicated in this communication. Here, we show that IQGAP1, a scaffold protein that regulates AS of distinct gene subsets in gastric cancer cells, participates in AS regulation that strongly affects mitochondrial respiration. Combined proteomic and RNA-seq analyses of IQGAP1KO and parental cells show that IQGAP1KO alters a specific AS event of the mitochondrial respiratory chain complex I (CI) subunit NDUFS4 and downregulates a subset of CI subunits. In IQGAP1KO cells, CI intermediates accumulate resembling assembly deficiencies observed in patients with Leigh syndrome bearing NDUFS4 mutations. Mitochondrial CI activity is significantly lower in KO compared to parental cells, while exogenous expression of IQGAP1 reverses mitochondrial defects of IQGAP1KO cells. Our work sheds light to a novel facet of IQGAP1 in mitochondrial quality control that involves fine-tuning of CI activity through AS regulation in gastric cancer.
2023-08-04 | GSE218220 | GEO
Project description:Heterogeneous nuclear ribonucleoproteins (hnRNPs) are involved in many processes in RNA metabolism. In addition to their functions in the nucleus, hnRNPs can function in the replication of RNA viruses in the cytoplasm. In vesicular stomatitis virus (VSV)-infected cells, several hnRNPs relocalize from the nucleus to the cytoplasm. This raises the question of whether these hnRNPs are relocalized together with their host nuclear RNAs or whether they associate with new RNAs in the cytoplasm. hnRNP A1, hnRNP C1/C2, and hnRNP K were immunoprecipitated from mock- or VSV-infected cells, and RNAs were analyzed by high content RNA sequencing. Each hnRNP displayed a loss of interaction with cellular transcripts in favor of viral mRNAs. hnRNP A1 was preferentially associated with VSV phosphoprotein (P) mRNA; hnRNP C1/C2 was preferentially associated with VSV glycoprotein (G) mRNA, and hnRNP K bound viral transcripts in rank of abundance.
2016-06-04 | GSE82226 | GEO
Project description:Nuclear IQGAP1 promotes gastric cancer cell growth by altering the splicing of a cell-cycle regulon in co-operation with hnRNPM
| PRJNA609974 | ENA
Project description:This SuperSeries is composed of the following subset Series: GSE10697: Self-Self Hybridisation were used to set confidence 99% intervals GSE10698: The effects of artificial tethering of chromosomes to the nuclear periphery using LacI/lap2b anchorage constructs 1 GSE10699: The effects of artificial tethering of chromosomes to the nuclear periphery using LacI/lap2b anchorage constructs 2 Background: The spatial organisation of the genome in the nucleus has a role in the regulation of gene expression. In mammals, chromosomal regions with low gene-density are located close to the nuclear periphery. Correlations have also been made between the transcriptional state of some genes and their location near the nuclear periphery. However, a crucial issue is whether this level of nuclear organisation directly affects gene function, rather than merely reflecting it. Methodology: To directly investigate whether proximity to the nuclear periphery can influence gene expression in mammalian cells. here we relocate specific human chromosomes to the nuclear periphery by tethering them to a protein of the inner nuclear membrane. Principal findings: We show that this can reversibly suppress the expression of some endogenous human genes located near the tethering sites, and even genes further away. However, the expression of many other genes is not detectably reduced and we show that location at the nuclear periphery is not incompatible with active transcription. The dampening of gene expression around the nuclear periphery is dependent on the activity of histone deacetylases. Significance: Our data show that the radial position within the nucleus can influence the expression of some, but not all, genes. This is compatible with the suggestion that re-localisation of genes to the peripheral zone of the nucleus could be used by metazoans to modulate the expression of selected genes during development and differentiation. Keywords: SuperSeries Refer to individual Series
2010-05-26 | E-GEOD-10701 | biostudies-arrayexpress
Project description:Tumor metastasis remains the major cause of cancer-related death, but its molecular basis is still not well understood. Here we uncovered a splicing-mediated pathway that is essential for breast cancer metastasis. We show that the RNA-binding protein hnRNPM promotes breast cancer metastasis by activating the switch of alternative splicing that occurs during epithelial-mesenchymal transition (EMT). Genome-wide deep sequencing analysis suggests that hnRNPM potentiates TGFb signaling and identifies CD44 as a key downstream target of hnRNPM. hnRNPM ablation prevents TGFb-induced EMT and inhibits breast cancer metastasis in mice, whereas enforced expression of the specific CD44s splice isoform overrides the loss of hnRNPM and permits EMT and metastasis. Mechanistically, we demonstrate that the ubiquitously expressed hnRNPM acts in a mesenchymal-specific manner to precisely control CD44 splice isoform switching during EMT. This restricted cell-type activity of hnRNPM is achieved by competition with ESRP1, an epithelial-splicing regulator that binds to the same cis-regulatory RNA elements and is repressed during EMT. Importantly, hnRNPM is associated with aggressive breast cancer and correlates with increased CD44s in patient specimens. These findings demonstrate a novel molecular mechanism through which tumor metastasis is endowed by the hnRNPM-mediated splicing program. RNAseq for control, hnRNPM siRNA treated lung metastatic LM2 clonal line, derived from the mesenchymal MDA-MB-231 cells
2014-06-03 | E-GEOD-57243 | biostudies-arrayexpress
Project description:Reiterer2013 - pseudophosphatase STYX role in
ERK signalling
This model is described in the article:
Pseudophosphatase STYX
modulates cell-fate decisions and cell migration by
spatiotemporal regulation of ERK1/2.
Reiterer V, Fey D, Kolch W,
Kholodenko BN, Farhan H.
Proc. Natl. Acad. Sci. U.S.A. 2013 Jul;
110(31): E2934-43
Abstract:
Serine/threonine/tyrosine-interacting protein (STYX) is a
catalytically inactive member of the dual-specificity
phosphatases (DUSPs) family. Whereas the role of DUSPs in
cellular signaling is well explored, the function of STYX is
still unknown. Here, we identify STYX as a spatial regulator of
ERK signaling. We used predictive-model simulation to test
several hypotheses for possible modes of STYX action. We show
that STYX localizes to the nucleus, competes with nuclear DUSP4
for binding to ERK, and acts as a nuclear anchor that regulates
ERK nuclear export. Depletion of STYX increases ERK activity in
both cytosol and nucleus. Importantly, depletion of STYX causes
an ERK-dependent fragmentation of the Golgi apparatus and
inhibits Golgi polarization and directional cell migration.
Finally, we show that overexpression of STYX reduces ERK1/2
activation, thereby blocking PC12 cell differentiation.
Overall, our results identify STYX as an important regulator of
ERK1/2 signaling critical for cell migration and PC12 cell
differentiation.
This model is hosted on
BioModels Database
and identified by:
BIOMD0000000557.
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To the extent possible under law, all copyright and related or
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2014-11-25 | BIOMD0000000557 | BioModels
Project description:Transcriptionally silent heterochromatin preferentially localizes at the nuclear periphery, but, despite this, certain budding yeast genes relocate to the nuclear periphery following gene activation, implicating the nuclear envelope in both transcriptional activation and silencing. It is unclear how these distinct chromatin domains are established, maintained and distinguished from one another at the nuclear envelope. Here we report that nuclear pore complexes (NPCs) facilitate the transition between chromatin states by providing a platform to which chromatin-remodeling and chromatin-modifying complexes bind. In particular, we show that the RSC chromatin-remodeling complex associates with NPCs and that the nucleoporin Nup170p nucleates heterochromatin formation at telomeres through recruitment of Sir4p. Deletion of NUP170 altered subtelomeric chromatin structure, reduced SIR complex binding at telomeres, impaired telomeric silencing and abated telomere tethering. These results support a model in which telomeric heterochromatin formation occurs through telomere-NPC interactions that both promote Sir4p binding at telomeres and permit chromatin-remodeling complexes to mediate the transition between chromatin states. Examination of genome-wide nucleosome positions in WT and nup170∆ cells via next-generation sequencing of mononucleosomal DNA.
2013-02-28 | E-GEOD-36792 | biostudies-arrayexpress
Project description:Background: The spatial organisation of the genome in the nucleus has a role in the regulation of gene expression. In mammals, chromosomal regions with low gene-density are located close to the nuclear periphery. Correlations have also been made between the transcriptional state of some genes and their location near the nuclear periphery. However, a crucial issue is whether this level of nuclear organisation directly affects gene function, rather than merely reflecting it. Methodology: To directly investigate whether proximity to the nuclear periphery can influence gene expression in mammalian cells. here we relocate specific human chromosomes to the nuclear periphery by tethering them to a protein of the inner nuclear membrane. Principal findings: We show that this can reversibly suppress the expression of some endogenous human genes located near the tethering sites, and even genes further away. However, the expression of many other genes is not detectably reduced and we show that location at the nuclear periphery is not incompatible with active transcription. The dampening of gene expression around the nuclear periphery is dependent on the activity of histone deacetylases. Significance: Our data show that the radial position within the nucleus can influence the expression of some, but not all, genes. This is compatible with the suggestion that re-localisation of genes to the peripheral zone of the nucleus could be used by metazoans to modulate the expression of selected genes during development and differentiation. This SuperSeries is composed of the SubSeries listed below.
2008-03-04 | GSE10701 | GEO