Integrating transcriptome, proteome, and phosphoproteome analysis reveals loss function of IQGAP2 promotes cell proliferation through the mTOR pathway
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE213715 | GEO | 2022/09/22
REPOSITORIES: GEO
Similar Datasets
Project description:Tuberous Sclerosis Complex (TSC) is a disease caused by autosomal dominant mutations in the TSC1 or TSC2 genes, and is characterized by tumor susceptibility, brain lesions, seizures and behavioral impairments. The TSC1 and TSC2 genes encode proteins forming a complex (TSC), which is a major regulator and suppressor of mammalian target of rapamycin (mTOR) in complex 1 (mTORC1), a signaling complex that promotes cell growth and proliferation. TSC1/2 loss of heterozygosity (LOH) and the subsequent complete loss of TSC regulatory activity in null cells causes mTORC1 dysregulation and TSC-associated brain lesions or other tissue tumors. However, it is not clear whether TSC1/2 heterozygous brain cells are abnormal and contribute to TSC neuropathology. To investigate this issue, we generated induced pluripotent stem cells (iPSCs) from TSC patients and unaffected controls, and utilized these to obtain neural progenitor cells (NPCs) and differentiated neurons in vitro. These patient-derived TSC2 heterozygous NPCs were delayed in their ability to differentiate into neurons. Patient-derived progenitor cells also exhibited a modest activation of mTORC1 signaling downstream of TSC, and a marked attenuation of upstream PI3K/AKT signaling. We further show that pharmacologic AKT inhibition, but not mTORC1 inhibition, causes a neuronal differentiation delay, mimicking the patient phenotype. Together these data suggest that heterozygous TSC2 mutations disrupt neuronal development, potentially contributing to the disease neuropathology, and that this defect may result from dysregulated AKT signaling in neural progenitor cells.
2018-08-26 | GSE111584 | GEO
Project description:The tuberous sclerosis complex (TSC) family of tumor suppressors, TSC1 and TSC2, function together in an evolutionarily conserved protein complex that is a point of convergence for major cell signaling pathways that regulate mTOR complex 1 (mTORC1). Mutation or aberrant inhibition of the TSC complex is common in various human tumor syndromes and cancers. The discovery of novel therapeutic strategies to selectively target cells with functional loss of this complex is therefore of substantial clinical relevance to TSC and sporadic cancers. We developed a CRISPR-based method to generate homogenous mutant Drosophila cell lines. By combining TSC1 and TSC2 mutant cell lines with RNAi screens against all kinases and phosphatases, we identified synthetic interactions with TSC1 and TSC2. Knockdown of three candidate genes (mRNA-cap, Pitslre and CycT; orthologs of RNGTT, CDK11 and CCNT1 in humans) reduced the population growth rate of both Drosophila TSC1 and TSC2 mutant cells but not that of wild-type cells. Moreover, knockdown of all three genes displayed similar selective effects in mammalian TSC2-deficient cell lines, including human tumor-derived cells, illustrating the power of this cross species screening strategy to identify potential drug targets.
2018-10-24 | PXD002670 | Pride
Project description:HSP90 and its co-chaperon R2TP are involved to assemble and stabilize many macro-molecular complexes involved in cell proliferation. R2TP complex is composed of RUVBL1 and RUVBL2 AAA+ ATPases and two adapter proteins RPAP3 and PIH1D1. The N-terminal domain of PIH1D1 was described to possess a basic pocket that binds phosphorylated peptides on some of the R2TP clients. Subunits of TSC complex (Tuberous SClerosis) have previously been described in proteomic analysis of proteins immune-precipitated with PIH1D1 N-terminal domain. TSC complex is a regulator of mTOR activity. It is composed of TSC1, TSC2 and TBC1D7 subunits. Here, we show that (i) TSC1 and TSC2 are both substrates of HSP90, (ii) the HSP90/R2TP system has multiple interaction with TSC complex subunits and (iii) it is functionally involved in the assembly of the TSC complex. We found a direct interaction of TSC1 with the phospho-binding pocket of PIH1D1 N-terminal domain regardless of phosphorylationbut in a non-canonical phosphorylation independent manner[XM1] . TSC2 and TBC1D7 would also interact with R2TP but independently of PIH1D1. Taken together, these data suggest that R2TP acts as a platform for the independent recruitment of TSC subunits before the assembly of the TSC complex
2024-11-12 | PXD030402 | Pride
Project description:DallePezze2012 - TSC-independent mTORC2
regulation
This model is described in the article:
A dynamic network model of
mTOR signaling reveals TSC-independent mTORC2 regulation.
Dalle Pezze P, Sonntag AG, Thien A,
Prentzell MT, Gödel M, Fischer S, Neumann-Haefelin E, Huber
TB, Baumeister R, Shanley DP, Thedieck K.
Sci Signal 2012 Mar; 5(217): ra25
Abstract:
The kinase mammalian target of rapamycin (mTOR) exists in
two multiprotein complexes (mTORC1 and mTORC2) and is a central
regulator of growth and metabolism. Insulin activation of
mTORC1, mediated by phosphoinositide 3-kinase (PI3K), Akt, and
the inhibitory tuberous sclerosis complex 1/2 (TSC1-TSC2),
initiates a negative feedback loop that ultimately inhibits
PI3K. We present a data-driven dynamic insulin-mTOR network
model that integrates the entire core network and used this
model to investigate the less well understood mechanisms by
which insulin regulates mTORC2. By analyzing the effects of
perturbations targeting several levels within the network in
silico and experimentally, we found that, in contrast to
current hypotheses, the TSC1-TSC2 complex was not a direct or
indirect (acting through the negative feedback loop) regulator
of mTORC2. Although mTORC2 activation required active PI3K,
this was not affected by the negative feedback loop. Therefore,
we propose an mTORC2 activation pathway through a PI3K variant
that is insensitive to the negative feedback loop that
regulates mTORC1. This putative pathway predicts that mTORC2
would be refractory to Akt, which inhibits TSC1-TSC2, and,
indeed, we found that mTORC2 was insensitive to constitutive
Akt activation in several cell types. Our results suggest that
a previously unknown network structure connects mTORC2 to its
upstream cues and clarifies which molecular connectors
contribute to mTORC2 activation.
This model is hosted on
BioModels Database
and identified by:
BIOMD0000000581.
To cite BioModels Database, please use:
BioModels Database:
An enhanced, curated and annotated resource for published
quantitative kinetic models.
To the extent possible under law, all copyright and related or
neighbouring rights to this encoded model have been dedicated to
the public domain worldwide. Please refer to
CC0
Public Domain Dedication for more information.
2024-09-02 | BIOMD0000000581 | BioModels
Project description:Tuberous sclerosis complex (TSC), an autosomal dominant disorder caused by mutations in either TSC1 or TSC2, exhibits white matter abnormalities including CNS myelin deficits. however, underlying mechanisms are not fully understood. Here we find that, unexpectedly, constitutive activation of mTOR signaling caused by Tsc1 deletion in the oligodendrocyte lineage results in severe myelination defects and oligodendrocyte cell death. Expression profiling analysis reveals that Tsc1 ablation induces prominent endoplasmic reticulum (ER) stress responses through the PERKâeIF2α dependent signaling axis and activates Fas-JNK apoptotic pathways. Our studies suggest that TSC1-mTOR signaling acts as an important checkpoint for maintaining oligodendrocyte homeostasis. Gene expression profiling of optic nerve from P12 control and Tsc1cKO mice
2016-07-22 | E-GEOD-74893 | biostudies-arrayexpress
Project description:Patients with tuberous sclerosis complex (TSC) develop hamartomas containing biallelic inactivating mutations in either TSC1 or TSC2, resulting in mammalian target of rapamycin (mTOR) activation. Hamartomas overgrow epithelial and mesenchymal cells in TSC skin. The pathogenetic mechanisms for these changes had not been investigated, and the existence or location of cells with biallelic mutations (âtwo-hitâ cells) that resulted in mTOR activation was unclear. We compared TSC skin hamartomas (facial angiofibromas and periungual fibromas) to normal-appearing skin of the same patient, and observed more proliferation and mTOR activation in hamartoma epidermis. âTwo-hitâ cells were not detected in the epidermis. Fibroblast-like cells in the dermis, however, exhibited allelic deletion of TSC2, in both touch preparations of fresh tumor samples and cells grown from TSC skin tumors, suggesting that increased epidermal proliferation and mTOR activation were not caused by second-hit mutations in the keratinocytes but by mesenchymal-epithelial interactions. Gene expression arrays, used to identify potential paracrine factors released by mesenchymal cells, revealed more epiregulin mRNA in fibroblast-like angiofibroma and periungual fibroma cells than in fibroblasts from normal-appearing skin of the same patient. Elevation of epiregulin mRNA was confirmed using real-time PCR, and increased amounts of epiregulin protein were demonstrated using immunoprecipitation and ELISA. Epiregulin stimulated keratinocyte proliferation and phosphorylation of ribosomal protein S6 in vitro. These results suggest that hamartomatous TSC skin tumors are induced by paracrine factors released by âtwo-hitâ cells in the dermis, and that proliferation with mTOR activation of the overlying epidermis is an effect of epiregulin. Experiment Overall Design: The study is of case/control design with biological replication. Tumor (case) and normal (control) fibroblast cells were isolated from each of four patients (biological replicates).
2008-04-06 | E-GEOD-9715 | biostudies-arrayexpress
Project description:Human Tsc1 and Tsc2 genes predispose to Tuberous Sclerosis Complex (TSC), a disorder characterized by the widespread of benign tumors. Tsc1 and Tsc2 proteins form a complex and serve as a GAP (GTP activating protein) for Rheb, a GTPase regulating a downstream kinase, mTor. The fission yeast genome contains tsc1+ and tsc2+, homologs of human Tsc1and Tsc2, respectively. In this study we analyzed gene expression profile in a genome-wide scale and found that deletion of either tsc1+ or tsc2+ affects gene induction upon nitrogen starvation. Three hours after nitrogen depletion genes encoding permeases and genes required for meiosis are less induced. Under the same condition, retrotransposons, G1-cyclin (pas1+) and a gene normally repressed by glucose (inv1+) are more induced. We also demonstrate that a mutation (cpp1-1) in a gene encoding aβ-subunit of a farnesyl transferase can suppress most of the phenotypes associated with deletion of tsc1+ or tsc2+. When a mutant of rhb1+ (homolog of human Rheb), which bypasses the requirement of protein farnesylation, was expressed, the cpp1-1 mutation could no longer suppress, indicating that deficient farnesylation of Rhb1 contributes to the suppression. Based on these results, we discuss the TSC-pathology and possible improvement in chemotherapy for TSC. Keywords: Keywards: Nitrogen starvation, Dtsc1. Dtsc2
2006-06-13 | GSE4449 | GEO
Project description:Tuberous Sclerosis Complex (TSC) is a neurodevelopmental disorder caused by mutations that inactivate TSC1 or TSC2. Hamartin and tuberin are encoded by TSC1 and TSC2 which form a GTPase activating protein heteromer that inhibits the Rheb GTPase from activating a growth promoting protein kinase called mammalian target of rapamycin (mTOR). Growths and lesions occur in the ventricular-subventricular zone (V-SVZ), cortex, olfactory tract, and olfactory bulbs (OB) in TSC. Here, nestin-CRE-ERT2 mice were injected with tamoxifen at postnatal days 2 and 3 and brains harvested at postnatal day 60. OBs were subsequently subjected to RNA sequencing.
2022-06-19 | GSE206287 | GEO
Project description:Tuberous Sclerosis Complex (TSC), an autosomal dominant condition, is engendered by heterozygous mutations in either TSC1 or TSC2 genes, manifesting in systemic growth of benign tumors. In addition to brain lesions, neurologic sequelae represent the greatest morbidity in TSC patients. Investigations utilizing TSC1/2-knockout animal or human stem cell models suggest that TSC deficiency-causing hyper-activation of mTOR signaling might precipitate anomalous neurodevelopmental processes. However, how the pathogenic variants of TSC1/2 genes identified in TSC patients affect the trajectory of human brain development and how they contribute to the neurological manifestations in TSC remain largely unexplored. Here, we employed 3-dimensional cortical organoids derived from induced pluripotent stem cells (iPSCs) from TSC patients harboring TSC2 mutations, alongside organoids from age- and sex-matched healthy individuals as controls. Through comprehensively longitudinal molecular and cellular analysis of TSC organoids, including transcriptomics and single cell transcriptomics, we found that TSC2 pathogenic variants led to dysregulated neurogenesis, synaptogenesis, and gliogenesis, particularly for reactive astrogliosis. The altered developmental trajectory of TSC organoids significantly resembles the molecular signatures of neuropsychiatric disorders, including autism spectrum disorders, epilepsy, and intellectual disability. Through cell-cell communication analysis at the single cell level, we identified that TSC2 pathogenic variants disrupted the cell-cell communications, in particular, neuron-astrocyte interactions within the NLGN-NRXN signaling network. Furthermore, cellular and electrophysiological assessments of TSC cortical organoids, along with proteomics and phosphoproteomics analyses of synaptosomes, revealed that pathogenic TSC2 variants precipitate perturbations in mitochondrial translational integrity, neurofilament formation, synaptic transmission, and neuronal network activity. Intriguingly, the increased neu
2024-11-22 | GSE247367 | GEO
Project description:Tuberous Sclerosis Complex (TSC), an autosomal dominant condition, is engendered by heterozygous mutations in either TSC1 or TSC2 genes, manifesting in systemic growth of benign tumors. In addition to brain lesions, neurologic sequelae represent the greatest morbidity in TSC patients. Investigations utilizing TSC1/2-knockout animal or human stem cell models suggest that TSC deficiency-causing hyper-activation of mTOR signaling might precipitate anomalous neurodevelopmental processes. However, how the pathogenic variants of TSC1/2 genes identified in TSC patients affect the trajectory of human brain development and how they contribute to the neurological manifestations in TSC remain largely unexplored. Here, we employed 3-dimensional cortical organoids derived from induced pluripotent stem cells (iPSCs) from TSC patients harboring TSC2 mutations, alongside organoids from age- and sex-matched healthy individuals as controls. Through comprehensively longitudinal molecular and cellular analysis of TSC organoids, including transcriptomics and single cell transcriptomics, we found that TSC2 pathogenic variants led to dysregulated neurogenesis, synaptogenesis, and gliogenesis, particularly for reactive astrogliosis. The altered developmental trajectory of TSC organoids significantly resembles the molecular signatures of neuropsychiatric disorders, including autism spectrum disorders, epilepsy, and intellectual disability. Through cell-cell communication analysis at the single cell level, we identified that TSC2 pathogenic variants disrupted the cell-cell communications, in particular, neuron-astrocyte interactions within the NLGN-NRXN signaling network. Furthermore, cellular and electrophysiological assessments of TSC cortical organoids, along with proteomics and phosphoproteomics analyses of synaptosomes, revealed that pathogenic TSC2 variants precipitate perturbations in mitochondrial translational integrity, neurofilament formation, synaptic transmission, and neuronal network activity. Intriguingly, the increased neu
2024-11-22 | GSE247368 | GEO