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1.
Phys Rev Lett ; 132(8): 080402, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38457728

RESUMEN

Quantum information scrambling is a unitary process that destroys local correlations and spreads information throughout the system, effectively hiding it in nonlocal degrees of freedom. In principle, unscrambling this information is possible with perfect knowledge of the unitary dynamics [B. Yoshida and A. Kitaev, arXiv:1710.03363.]. However, this Letter demonstrates that even without previous knowledge of the internal dynamics, information can be efficiently decoded from an unknown scrambler by monitoring the outgoing information of a local subsystem. We show that rapidly mixing but not fully chaotic scramblers can be decoded using Clifford decoders. The essential properties of a scrambling unitary can be efficiently recovered, even if the process is exponentially complex. Specifically, we establish that a unitary operator composed of t non-Clifford gates admits a Clifford decoder up to t≤n.

2.
Cell Rep Med ; 4(12): 101306, 2023 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-38052214

RESUMEN

Skeletal muscle atrophy is a hallmark of cachexia, a wasting condition typical of chronic pathologies, that still represents an unmet medical need. Bone morphogenetic protein (BMP)-Smad1/5/8 signaling alterations are emerging drivers of muscle catabolism, hence, characterizing these perturbations is pivotal to develop therapeutic approaches. We identified two promoters of "BMP resistance" in cancer cachexia, specifically the BMP scavenger erythroferrone (ERFE) and the intracellular inhibitor FKBP12. ERFE is upregulated in cachectic cancer patients' muscle biopsies and in murine cachexia models, where its expression is driven by STAT3. Moreover, the knock down of Erfe or Fkbp12 reduces muscle wasting in cachectic mice. To bypass the BMP resistance mediated by ERFE and release the brake on the signaling, we targeted FKBP12 with low-dose FK506. FK506 restores BMP-Smad1/5/8 signaling, rescuing myotube atrophy by inducing protein synthesis. In cachectic tumor-bearing mice, FK506 prevents muscle and body weight loss and protects from neuromuscular junction alteration, suggesting therapeutic potential for targeting the ERFE-FKBP12 axis.


Asunto(s)
Caquexia , Neoplasias , Humanos , Ratones , Animales , Caquexia/tratamiento farmacológico , Caquexia/etiología , Caquexia/metabolismo , Tacrolimus/metabolismo , Tacrolimus/farmacología , Músculo Esquelético/metabolismo , Proteína 1A de Unión a Tacrolimus/genética , Proteína 1A de Unión a Tacrolimus/metabolismo , Proteína 1A de Unión a Tacrolimus/farmacología , Atrofia Muscular/tratamiento farmacológico , Atrofia Muscular/metabolismo , Atrofia Muscular/patología , Neoplasias/patología
4.
Brief Funct Genomics ; 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37801430

RESUMEN

Embryonic stem cells (ESCs) preserve the unique ability to differentiate into any somatic cell lineage while maintaining their self-renewal potential, relying on a complex interplay of extracellular signals regulating the expression/activity of pluripotency transcription factors and their targets. Leukemia inhibitory factor (LIF)-activated STAT3 drives ESCs' stemness by a number of mechanisms, including the transcriptional induction of pluripotency factors such as Klf4 and the maintenance of a stem-like epigenetic landscape. However, it is unknown if STAT3 directly controls stem-cell specific non-coding RNAs, crucial to balance pluripotency and differentiation. Applying a bioinformatic pipeline, here we identify Lncenc1 in mouse ESCs as an STAT3-dependent long non-coding RNA that supports pluripotency. Lncenc1 acts in the cytoplasm as a positive feedback regulator of the LIF-STAT3 axis by competing for the binding of microRNA-128 to the 3'UTR of the Klf4 core pluripotency factor mRNA, enhancing its expression. Our results unveil a novel non-coding RNA-based mechanism for LIF-STAT3-mediated pluripotency.

5.
Nat Commun ; 14(1): 6109, 2023 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-37777550

RESUMEN

The influence of aging on intestinal stem cells and their niche can explain underlying causes for perturbation in their function observed during aging. Molecular mechanisms for such a decrease in the functionality of intestinal stem cells during aging remain largely undetermined. Using transcriptome-wide approaches, our study demonstrates that aging intestinal stem cells strongly upregulate antigen presenting pathway genes and over-express secretory lineage marker genes resulting in lineage skewed differentiation into the secretory lineage and strong upregulation of MHC class II antigens in the aged intestinal epithelium. Mechanistically, we identified an increase in proinflammatory cells in the lamina propria as the main source of elevated interferon gamma (IFNγ) in the aged intestine, that leads to the induction of Stat1 activity in intestinal stem cells thus priming the aberrant differentiation and elevated antigen presentation in epithelial cells. Of note, systemic inhibition of IFNγ-signaling completely reverses these aging phenotypes and reinstalls regenerative capacity of the aged intestinal epithelium.


Asunto(s)
Interferón gamma , Intestinos , Homeostasis , Interferón gamma/metabolismo , Mucosa Intestinal , Intestinos/metabolismo , Animales , Ratones , Factor de Transcripción STAT1/metabolismo
6.
Mol Ther Nucleic Acids ; 33: 47-48, 2023 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-37449044
7.
Dis Model Mech ; 16(6)2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-37260288

RESUMEN

The nuclear receptor NR2F1 acts as a strong transcriptional regulator in embryonic and postnatal neural cells. In humans, mutations in the NR2F1 gene cause Bosch-Boonstra-Schaaf optic atrophy syndrome (BBSOAS), a rare neurodevelopmental disorder characterized by multiple clinical features including vision impairment, intellectual disability and autistic traits. In this study, we identified, by genome-wide and in silico analyses, a set of nuclear-encoded mitochondrial genes as potential genomic targets under direct NR2F1 transcriptional control in neurons. By combining mouse genetic, neuroanatomical and imaging approaches, we demonstrated that conditional NR2F1 loss of function within the adult mouse hippocampal neurogenic niche results in a reduced mitochondrial mass associated with mitochondrial fragmentation and downregulation of key mitochondrial proteins in newborn neurons, the genesis, survival and functional integration of which are impaired. Importantly, we also found dysregulation of several nuclear-encoded mitochondrial genes and downregulation of key mitochondrial proteins in the brain of Nr2f1-heterozygous mice, a validated BBSOAS model. Our data point to an active role for NR2F1 in the mitochondrial gene expression regulatory network in neurons and support the involvement of mitochondrial dysfunction in BBSOAS pathogenesis.


Asunto(s)
Factor de Transcripción COUP I , Anomalías del Ojo , Discapacidad Intelectual , Atrofia Óptica , Animales , Humanos , Ratones , Encéfalo/metabolismo , Factor de Transcripción COUP I/genética , Anomalías del Ojo/genética , Anomalías del Ojo/metabolismo , Discapacidad Intelectual/genética , Mitocondrias , Mutación/genética , Atrofia Óptica/genética , Atrofia Óptica/metabolismo
8.
Comput Struct Biotechnol J ; 21: 3091-3102, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37273849

RESUMEN

Long non-coding RNAs (lncRNAs) regulate gene expression through different molecular mechanisms, including DNA binding via the formation of RNA:DNA:DNA triple helices (TPXs). Despite the increasing amount of experimental evidence, TPXs investigation remains challenging. Here we present 3plex, a software able to predict TPX interactions in silico. Given an RNA sequence and a set of DNA sequences, 3plex integrates 1) Hoogsteen pairing rules that describe the biochemical interactions between RNA and DNA nucleotides, 2) RNA secondary structure prediction and 3) determination of the TPX thermal stability derived from a collection of TPX experimental evidences. We systematically collected and uniformly re-analysed published experimental lncRNA binding sites on human and mouse genomes. We used these data to evaluate 3plex performance and showed that its specific features allow a reliable identification of TPX interactions. We compared 3plex with the other available software and obtained comparable or even better accuracy at a fraction of the computation time. Interestingly, by inspecting collected data with 3plex we found that TPXs tend to be shorter and more degenerated than previously expected and that the majority of analysed lncRNAs can directly bind to the genome by TPX formation. Those results suggest that an important fraction of lncRNAs can exert its biological function through this mechanism. The software is available at https://github.com/molinerisLab/3plex.

9.
Nat Commun ; 14(1): 2350, 2023 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-37169737

RESUMEN

The p140Cap adaptor protein is a tumor suppressor in breast cancer associated with a favorable prognosis. Here we highlight a function of p140Cap in orchestrating local and systemic tumor-extrinsic events that eventually result in inhibition of the polymorphonuclear myeloid-derived suppressor cell function in creating an immunosuppressive tumor-promoting environment in the primary tumor, and premetastatic niches at distant sites. Integrative transcriptomic and preclinical studies unravel that p140Cap controls an epistatic axis where, through the upstream inhibition of ß-Catenin, it restricts tumorigenicity and self-renewal of tumor-initiating cells limiting the release of the inflammatory cytokine G-CSF, required for polymorphonuclear myeloid-derived suppressor cells to exert their local and systemic tumor conducive function. Mechanistically, p140Cap inhibition of ß-Catenin depends on its ability to localize in and stabilize the ß-Catenin destruction complex, promoting enhanced ß-Catenin inactivation. Clinical studies in women show that low p140Cap expression correlates with reduced presence of tumor-infiltrating lymphocytes and more aggressive tumor types in a large cohort of real-life female breast cancer patients, highlighting the potential of p140Cap as a biomarker for therapeutic intervention targeting the ß-Catenin/ Tumor-initiating cells /G-CSF/ polymorphonuclear myeloid-derived suppressor cell axis to restore an efficient anti-tumor immune response.


Asunto(s)
Neoplasias de la Mama , Femenino , Humanos , beta Catenina/metabolismo , Mama/patología , Neoplasias de la Mama/genética , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Inmunidad , Células Madre Neoplásicas/inmunología , Células Madre Neoplásicas/metabolismo
10.
Nat Cell Biol ; 25(5): 740-753, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37081165

RESUMEN

Epithelial cells that participated in wound repair elicit a more efficient response to future injuries, which is believed to be locally restricted. Here we show that cell adaptation resulting from a localized tissue damage has a wide spatial impact at a scale not previously appreciated. We demonstrate that a specific stem cell population, distant from the original injury, originates long-lasting wound memory progenitors residing in their own niche. Notably, these distal memory cells have not taken part in the first healing but become intrinsically pre-activated through priming. This cell state, maintained at the chromatin and transcriptional level, leads to an enhanced wound repair that is partially recapitulated through epigenetic perturbation. Importantly wound memory has long-term harmful consequences, exacerbating tumourigenesis. Overall, we show that sub-organ-scale adaptation to injury relies on spatially organized memory-dedicated progenitors, characterized by an actionable cell state that establishes an epigenetic field cancerization and predisposes to tumour onset.


Asunto(s)
Células Epiteliales , Cicatrización de Heridas , Cicatrización de Heridas/fisiología , Células Epiteliales/fisiología , Cromatina/genética , Células Madre/fisiología
11.
Nat Commun ; 14(1): 367, 2023 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-36690616

RESUMEN

The correct establishment of DNA methylation patterns during mouse early development is essential for cell fate specification. However, the molecular targets as well as the mechanisms that determine the specificity of the de novo methylation machinery during differentiation are not completely elucidated. Here we show that the DNMT3B-dependent DNA methylation of key developmental regulatory regions at epiblast-like cells (EpiLCs) provides an epigenetic priming that ensures flawless commitment at later stages. Using in vitro stem cell differentiation and loss of function experiments combined with high-throughput genome-wide bisulfite-, bulk-, and single cell RNA-sequencing we dissected the specific role of DNMT3B in cell fate. We identify DNMT3B-dependent regulatory elements on the genome which, in Dnmt3b knockout (3BKO), impair the differentiation into meso-endodermal (ME) progenitors and redirect EpiLCs towards the neuro-ectodermal lineages. Moreover, ectopic expression of DNMT3B in 3BKO re-establishes the DNA methylation of the master regulator Sox2 super-enhancer, downmodulates its expression, and restores the expression of ME markers. Taken together, our data reveal that DNMT3B-dependent methylation at the epiblast stage is essential for the priming of the meso-endodermal lineages and provide functional characterization of the de novo DNMTs during EpiLCs lineage determination.


Asunto(s)
Endodermo , Células Madre Embrionarias de Ratones , Animales , Ratones , Células Madre Embrionarias de Ratones/metabolismo , Endodermo/metabolismo , ADN (Citosina-5-)-Metiltransferasas/genética , Diferenciación Celular , Linaje de la Célula , Metilación de ADN
12.
Front Immunol ; 13: 915963, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36131938

RESUMEN

Costimulatory molecules of the CD28 family play a crucial role in the activation of immune responses in T lymphocytes, complementing and modulating signals originating from the T-cell receptor (TCR) complex. Although distinct functional roles have been demonstrated for each family member, the specific signaling pathways differentiating ICOS- from CD28-mediated costimulation during early T-cell activation are poorly characterized. In the present study, we have performed RNA-Seq-based global transcriptome profiling of anti-CD3-treated naïve CD4+ T cells upon costimulation through either inducible costimulator (ICOS) or CD28, revealing a set of signaling pathways specifically associated with each signal. In particular, we show that CD3/ICOS costimulation plays a major role in pathways related to STAT3 function and osteoarthritis (OA), whereas the CD3/CD28 axis mainly regulates p38 MAPK signaling. Furthermore, we report the activation of distinct immunometabolic pathways, with CD3/ICOS costimulation preferentially targeting glycosaminoglycans (GAGs) and CD3/CD28 regulating mitochondrial respiratory chain and cholesterol biosynthesis. These data suggest that ICOS and CD28 costimulatory signals play distinct roles during the activation of naïve T cells by modulating distinct sets of immunological and immunometabolic genes.


Asunto(s)
Antígenos CD28 , Linfocitos T CD4-Positivos , Colesterol/metabolismo , Glicosaminoglicanos/metabolismo , Humanos , Proteína Coestimuladora de Linfocitos T Inducibles/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , Transcripción Genética , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
13.
Cell Rep ; 40(13): 111404, 2022 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-36170835

RESUMEN

Dysregulation of alternative splicing in prostate cancer is linked to transcriptional programs activated by AR, ERG, FOXA1, and MYC. Here, we show that FOXA1 functions as the primary orchestrator of alternative splicing dysregulation across 500 primary and metastatic prostate cancer transcriptomes. We demonstrate that FOXA1 binds to the regulatory regions of splicing-related genes, including HNRNPK and SRSF1. By controlling trans-acting factor expression, FOXA1 exploits an "exon definition" mechanism calibrating alternative splicing toward dominant isoform production. This regulation especially impacts splicing factors themselves and leads to a reduction of nonsense-mediated decay (NMD)-targeted isoforms. Inclusion of the NMD-determinant FLNA exon 30 by FOXA1-controlled oncogene SRSF1 promotes cell growth in vitro and predicts disease recurrence. Overall, we report a role for FOXA1 in rewiring the alternative splicing landscape in prostate cancer through a cascade of events from chromatin access, to splicing factor regulation, and, finally, to alternative splicing of exons influencing patient survival.


Asunto(s)
Empalme Alternativo , Neoplasias de la Próstata , Empalme Alternativo/genética , Cromatina , Factor Nuclear 3-alfa del Hepatocito/genética , Factor Nuclear 3-alfa del Hepatocito/metabolismo , Humanos , Masculino , Recurrencia Local de Neoplasia , Neoplasias de la Próstata/genética , Factores de Empalme de ARN/metabolismo , Factores de Empalme Serina-Arginina/metabolismo , Transactivadores/metabolismo
14.
Nat Commun ; 13(1): 5191, 2022 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-36057632

RESUMEN

Epithelial-mesenchymal transition (EMT) is a complex and pivotal process involved in organogenesis and is related to several pathological processes, including cancer and fibrosis. During heart development, EMT mediates the conversion of epicardial cells into vascular smooth muscle cells and cardiac interstitial fibroblasts. Here, we show that the oncogenic transcription factor EB (TFEB) is a key regulator of EMT in epicardial cells and that its genetic overexpression in mouse epicardium is lethal due to heart defects linked to impaired EMT. TFEB specifically orchestrates the EMT-promoting function of transforming growth factor (TGF) ß, and this effect results from activated transcription of thymine-guanine-interacting factor (TGIF)1, a TGFß/Smad pathway repressor. The Tgif1 promoter is activated by TFEB, and in vitro and in vivo findings demonstrate its increased expression when Tfeb is overexpressed. Furthermore, Tfeb overexpression in vitro prevents TGFß-induced EMT, and this effect is abolished by Tgif1 silencing. Tfeb loss of function, similar to that of Tgif1, sensitizes cells to TGFß, inducing an EMT response to low doses of TGFß. Together, our findings reveal an unexpected function of TFEB in regulating EMT, which might provide insights into injured heart repair and control of cancer progression.


Asunto(s)
Transición Epitelial-Mesenquimal , Factor de Crecimiento Transformador beta , Animales , Células Cultivadas , Transición Epitelial-Mesenquimal/fisiología , Ratones , Organogénesis , Pericardio/metabolismo , Factor de Crecimiento Transformador beta/metabolismo
15.
BMC Biol ; 20(1): 171, 2022 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-35918713

RESUMEN

BACKGROUND: The high-mobility group Hmga family of proteins are non-histone chromatin-interacting proteins which have been associated with a number of nuclear functions, including heterochromatin formation, replication, recombination, DNA repair, transcription, and formation of enhanceosomes. Due to its role based on dynamic interaction with chromatin, Hmga2 has a pathogenic role in diverse tumors and has been mainly studied in a cancer context; however, whether Hmga2 has similar physiological functions in normal cells remains less explored. Hmga2 was additionally shown to be required during the exit of embryonic stem cells (ESCs) from the ground state of pluripotency, to allow their transition into epiblast-like cells (EpiLCs), and here, we use that system to gain further understanding of normal Hmga2 function. RESULTS: We demonstrated that Hmga2 KO pluripotent stem cells fail to develop into EpiLCs. By using this experimental system, we studied the chromatin changes that take place upon the induction of EpiLCs and we observed that the loss of Hmga2 affects the histone mark H3K27me3, whose levels are higher in Hmga2 KO cells. Accordingly, a sustained expression of polycomb repressive complex 2 (PRC2), responsible for H3K27me3 deposition, was observed in KO cells. However, gene expression differences between differentiating wt vs Hmga2 KO cells did not show any significant enrichments of PRC2 targets. Similarly, endogenous Hmga2 association to chromatin in epiblast stem cells did not show any clear relationships with gene expression modification observed in Hmga2 KO. Hmga2 ChIP-seq confirmed that this protein preferentially binds to the chromatin regions associated with nuclear lamina. Starting from this observation, we demonstrated that nuclear lamina underwent severe alterations when Hmga2 KO or KD cells were induced to exit from the naïve state and this phenomenon is accompanied by a mislocalization of the heterochromatin mark H3K9me3 within the nucleus. As nuclear lamina (NL) is involved in the organization of 3D chromatin structure, we explored the possible effects of Hmga2 loss on this phenomenon. The analysis of Hi-C data in wt and Hmga2 KO cells allowed us to observe that inter-TAD (topologically associated domains) interactions in Hmga2 KO cells are different from those observed in wt cells. These differences clearly show a peculiar compartmentalization of inter-TAD interactions in chromatin regions associated or not to nuclear lamina. CONCLUSIONS: Overall, our results indicate that Hmga2 interacts with heterochromatic lamin-associated domains, and highlight a role for Hmga2 in the crosstalk between chromatin and nuclear lamina, affecting the establishment of inter-TAD interactions.


Asunto(s)
Membrana Nuclear , Células Madre Pluripotentes , Cromatina/genética , Cromatina/metabolismo , Proteína HMGA2/genética , Proteína HMGA2/metabolismo , Heterocromatina/metabolismo , Histonas/genética , Membrana Nuclear/metabolismo , Células Madre Pluripotentes/metabolismo , Complejo Represivo Polycomb 2/genética
16.
Cell Death Dis ; 13(6): 576, 2022 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-35773274

RESUMEN

The development of different generations of BCR-ABL1 tyrosine kinase inhibitors (TKIs) has led to the high overall survival of chronic myeloid leukemia (CML) patients. However, there are CML patients who show resistance to TKI therapy and are prone to progress to more advanced phases of the disease. So, implementing an alternative approach for targeting TKIs insensitive cells would be of the essence. Dihydroorotate dehydrogenase (DHODH) is an enzyme in the de novo pyrimidine biosynthesis pathway that is located in the inner membrane of mitochondria. Here, we found that CML cells are vulnerable to DHODH inhibition mediated by Meds433, a new and potent DHODH inhibitor recently developed by our group. Meds433 significantly activates the apoptotic pathway and leads to the reduction of amino acids and induction of huge metabolic stress in CML CD34+ cells. Altogether, our study shows that DHODH inhibition is a promising approach for targeting CML stem/progenitor cells and may help more patients discontinue the therapy.


Asunto(s)
Dihidroorotato Deshidrogenasa , Leucemia Mielógena Crónica BCR-ABL Positiva , Resistencia a Antineoplásicos , Proteínas de Fusión bcr-abl/metabolismo , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Inhibidores de Proteínas Quinasas/farmacología
17.
Int J Mol Sci ; 23(11)2022 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-35682796

RESUMEN

In the human brain, long non-coding RNAs (lncRNAs) are widely expressed in an exquisitely temporally and spatially regulated manner, thus suggesting their contribution to normal brain development and their probable involvement in the molecular pathology of neurodevelopmental disorders (NDD). Bypassing the classic protein-centric conception of disease mechanisms, some studies have been conducted to identify and characterize the putative roles of non-coding sequences in the genetic pathogenesis and diagnosis of complex diseases. However, their involvement in NDD, and more specifically in intellectual disability (ID), is still poorly documented and only a few genomic alterations affecting the lncRNAs function and/or expression have been causally linked to the disease endophenotype. Considering that a significant fraction of patients still lacks a genetic or molecular explanation, we expect that a deeper investigation of the non-coding genome will unravel novel pathogenic mechanisms, opening new translational opportunities. Here, we present evidence of the possible involvement of many lncRNAs in the etiology of different forms of ID and NDD, grouping the candidate disease-genes in the most frequently affected cellular processes in which ID-risk genes were previously collected. We also illustrate new approaches for the identification and prioritization of NDD-risk lncRNAs, together with the current strategies to exploit them in diagnosis.


Asunto(s)
Discapacidad Intelectual , Trastornos del Neurodesarrollo , ARN Largo no Codificante , Genómica , Humanos , Discapacidad Intelectual/genética , Trastornos del Neurodesarrollo/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo
18.
FASEB J ; 36(7): e22401, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35726676

RESUMEN

During skeletal myogenesis, the zinc-finger transcription factors SNAI1 and SNAI2, are expressed in proliferating myoblasts and regulate the transition to terminally differentiated myotubes while repressing pro-differentiation genes. Here, we demonstrate that SNAI1 is upregulated in vivo during the early phase of muscle regeneration induced by bupivacaine injury. Using shRNA-mediated gene silencing in C2C12 myoblasts and whole-transcriptome microarray analysis, we identified a collection of genes belonging to the endoplasmic reticulum (ER) stress pathway whose expression, induced by myogenic differentiation, was upregulated in absence of SNAI1. Among these, key ER stress genes, such as Atf3, Ddit3/Chop, Hspa5/Bip, and Fgf21, a myokine involved in muscle differentiation, were strongly upregulated. Furthermore, by promoter mutant analysis and Chromatin immune precipitation assay, we demonstrated that SNAI1 represses Fgf21 and Atf3 in proliferating myoblasts by directly binding to multiple E boxes in their respective promoter regions. Together, these data describe a new regulatory mechanism of myogenic differentiation involving the direct repressive action of SNAI1 on ER stress and Fgf21 expression, ultimately contributing to maintaining the proliferative and undifferentiated state of myoblasts.


Asunto(s)
Desarrollo de Músculos , Fibras Musculares Esqueléticas , Factores de Transcripción de la Familia Snail/metabolismo , Factor de Transcripción Activador 3/metabolismo , Diferenciación Celular , Línea Celular , Factores de Crecimiento de Fibroblastos , Desarrollo de Músculos/genética , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/fisiología , Regiones Promotoras Genéticas/genética , Regulación hacia Arriba
19.
Phys Rev Lett ; 128(5): 050402, 2022 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-35179939

RESUMEN

We introduce a novel measure for the quantum property of "nonstabilizerness"-commonly known as "magic"-by considering the Rényi entropy of the probability distribution associated to a pure quantum state given by the square of the expectation value of Pauli strings in that state. We show that this is a good measure of nonstabilizerness from the point of view of resource theory and show bounds with other known measures. The stabilizer Rényi entropy has the advantage of being easily computable because it does not need a minimization procedure. We present a protocol for an experimental measurement by randomized measurements. We show that the nonstabilizerness is intimately connected to out-of-time-order correlation functions and that maximal levels of nonstabilizerness are necessary for quantum chaos.

20.
Nucleic Acids Res ; 50(5): 2587-2602, 2022 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-35137201

RESUMEN

The histone acetyltransferase p300 (also known as KAT3B) is a general transcriptional coactivator that introduces the H3K27ac mark on enhancers triggering their activation and gene transcription. Genome-wide screenings demonstrated that a large fraction of long non-coding RNAs (lncRNAs) plays a role in cellular processes and organ development although the underlying molecular mechanisms remain largely unclear (1,2). We found 122 lncRNAs that interacts directly with p300. In depth analysis of one of these, lncSmad7, is required to maintain ESC self-renewal and it interacts to the C-terminal domain of p300. lncSmad7 also contains predicted RNA-DNA Hoogsteen forming base pairing. Combined Chromatin Isolation by RNA precipitation followed by sequencing (ChIRP-seq) together with CRISPR/Cas9 mutagenesis of the target sites demonstrate that lncSmad7 binds and recruits p300 to enhancers in trans, to trigger enhancer acetylation and transcriptional activation of its target genes. Thus, these results unveil a new mechanism by which p300 is recruited to the genome.


Asunto(s)
Histonas , ARN Largo no Codificante , Acetilación , Acetiltransferasas/metabolismo , Cromatina/genética , Elementos de Facilitación Genéticos , Histonas/genética , Histonas/metabolismo , ARN Largo no Codificante/metabolismo , Factores de Transcripción p300-CBP/genética , Factores de Transcripción p300-CBP/metabolismo
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