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1.
Int J Biol Sci ; 20(7): 2622-2639, 2024.
Article En | MEDLINE | ID: mdl-38725840

Sorafenib is a standard first-line drug for advanced hepatocellular carcinoma, but the serious cardiotoxic effects restrict its therapeutic applicability. Here, we show that iron-dependent ferroptosis plays a vital role in sorafenib-induced cardiotoxicity. Remarkably, our in vivo and in vitro experiments demonstrated that ferroptosis inhibitor application neutralized sorafenib-induced heart injury. By analyzing transcriptome profiles of adult human sorafenib-treated cardiomyocytes, we found that Krüppel-like transcription factor 11 (KLF11) expression significantly increased after sorafenib stimulation. Mechanistically, KLF11 promoted ferroptosis by suppressing transcription of ferroptosis suppressor protein 1 (FSP1), a seminal breakthrough due to its ferroptosis-repressing properties. Moreover, FSP1 knockdown showed equivalent results to glutathione peroxidase 4 (GPX4) knockdown, and FSP1 overexpression counteracted GPX4 inhibition-induced ferroptosis to a substantial extent. Cardiac-specific overexpression of FSP1 and silencing KLF11 by an adeno-associated virus serotype 9 markedly improved cardiac dysfunction in sorafenib-treated mice. In summary, FSP1-mediated ferroptosis is a crucial mechanism for sorafenib-provoked cardiotoxicity, and targeting ferroptosis may be a promising therapeutic strategy for alleviating sorafenib-induced cardiac damage.


Cardiotoxicity , Ferroptosis , S100 Calcium-Binding Protein A4 , Sorafenib , Sorafenib/adverse effects , Ferroptosis/drug effects , Animals , Mice , Cardiotoxicity/metabolism , Cardiotoxicity/etiology , Humans , S100 Calcium-Binding Protein A4/metabolism , S100 Calcium-Binding Protein A4/genetics , Male , Mice, Inbred C57BL , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/drug effects , Repressor Proteins/metabolism , Repressor Proteins/genetics
2.
Int J Biol Sci ; 20(7): 2422-2439, 2024.
Article En | MEDLINE | ID: mdl-38725842

Background & Aims: Reactive oxygen species (ROS) act as modulators triggering cellular dysfunctions and organ damage including liver fibrosis in which hepatic stellate cell (HSC) activation plays a key role. Previous studies suggest that microRNA-144 (miR-144) acts as a pro-oxidant molecule; however, whether and how miR-144 affects HSC activation and liver fibrosis remain unknown. Methods: Carbon tetrachloride (CCl4) and bile duct ligation (BDL)-induced experimental liver fibrosis models were used. Hepatic miR-144 expression was analyzed by miRNA in situ hybridization with RNAscope probe. The in vivo effects of silencing or overexpressing miR-144 were examined with an adeno-associated virus 6 (AAV6) carrying miR-144 inhibitor or mimics in fibrotic mouse experimental models. Results: In this study, we demonstrated that ROS treatment significantly upregulated miR-144 in HSCs, which further promoted HSC activation in vitro. Interestingly, miR-144 was preferentially elevated in HSCs of experimental liver fibrosis in mice and in human liver fibrotic tissues. Furthermore, in vivo loss or gain-of-function experiments via AAV6 carrying miR-144 antagomir or agomir revealed that blockade of miR-144 in HSCs mitigated, while overexpression of miR-144 in HSCs accelerated the development of experimental liver fibrosis. Mechanistically, SIN3 transcription regulator family member A (SIN3A), a transcriptional repressor, was identified to be the target of miR-144 in HSCs. MiR-144 downregulated Sin3A, and in line with this result, specific knockdown of Sin3a in HSCs remarkedly activated p38 MAPK signaling pathway to promote HSC activation, eventually exacerbating liver fibrosis. Conclusions: Oxidative stress-driven miR-144 fuels HSC activation and liver fibrogenesis by limiting the SIN3A-p38 axis. Thus, a specific inhibition of miR-144 in HSCs could be a novel therapeutic strategy for the treatment of liver fibrosis.


Hepatic Stellate Cells , Liver Cirrhosis , MicroRNAs , Oxidative Stress , Reactive Oxygen Species , Sin3 Histone Deacetylase and Corepressor Complex , p38 Mitogen-Activated Protein Kinases , MicroRNAs/metabolism , MicroRNAs/genetics , Animals , Hepatic Stellate Cells/metabolism , Liver Cirrhosis/metabolism , Liver Cirrhosis/genetics , Liver Cirrhosis/pathology , Mice , Humans , p38 Mitogen-Activated Protein Kinases/metabolism , Sin3 Histone Deacetylase and Corepressor Complex/metabolism , Reactive Oxygen Species/metabolism , Male , Mice, Inbred C57BL , Repressor Proteins/metabolism , Repressor Proteins/genetics , Carbon Tetrachloride
3.
Cells ; 13(9)2024 Apr 23.
Article En | MEDLINE | ID: mdl-38727269

The histone deacetylase inhibitor (HDACi) valproic acid (VPA) has neuroprotective and anti-inflammatory effects in experimental traumatic brain injury (TBI), which have been partially attributed to the epigenetic disinhibition of the transcription repressor RE1-Silencing Transcription Factor/Neuron-Restrictive Silencer Factor (REST/NRSF). Additionally, VPA changes post-traumatic brain injury (TBI) brain metabolism to create a neuroprotective environment. To address the interconnection of neuroprotection, metabolism, inflammation and REST/NRSF after TBI, we subjected C57BL/6N mice to experimental TBI and intraperitoneal VPA administration or vehicle solution at 15 min, 1, 2, and 3 days post-injury (dpi). At 7 dpi, TBI-induced an up-regulation of REST/NRSF gene expression and HDACi function of VPA on histone H3 acetylation were confirmed. Neurological deficits, brain lesion size, blood-brain barrier permeability, or astrogliosis were not affected, and REST/NRSF target genes were only marginally influenced by VPA. However, VPA attenuated structural damage in the hippocampus, microgliosis and expression of the pro-inflammatory marker genes. Analyses of plasma lipidomic and polar metabolomic patterns revealed that VPA treatment increased lysophosphatidylcholines (LPCs), which were inversely associated with interleukin 1 beta (Il1b) and tumor necrosis factor (Tnf) gene expression in the brain. The results show that VPA has mild neuroprotective and anti-inflammatory effects likely originating from favorable systemic metabolic changes resulting in increased plasma LPCs that are known to be actively taken up by the brain and function as carriers for neuroprotective polyunsaturated fatty acids.


Brain Injuries, Traumatic , Inflammation , Lysophosphatidylcholines , Mice, Inbred C57BL , Neurons , Valproic Acid , Animals , Brain Injuries, Traumatic/drug therapy , Brain Injuries, Traumatic/pathology , Brain Injuries, Traumatic/blood , Brain Injuries, Traumatic/complications , Valproic Acid/pharmacology , Valproic Acid/therapeutic use , Mice , Male , Neurons/drug effects , Neurons/pathology , Neurons/metabolism , Inflammation/pathology , Inflammation/drug therapy , Lysophosphatidylcholines/blood , Cell Death/drug effects , Disease Models, Animal , Histone Deacetylase Inhibitors/pharmacology , Histone Deacetylase Inhibitors/therapeutic use , Neuroprotective Agents/pharmacology , Neuroprotective Agents/therapeutic use , Repressor Proteins/metabolism , Repressor Proteins/genetics
4.
Nat Commun ; 15(1): 3916, 2024 May 10.
Article En | MEDLINE | ID: mdl-38729927

The UK observed a marked increase in scarlet fever and invasive group A streptococcal infection in 2022 with severe outcomes in children and similar trends worldwide. Here we report lineage M1UK to be the dominant source of invasive infections in this upsurge. Compared with ancestral M1global strains, invasive M1UK strains exhibit reduced genomic diversity and fewer mutations in two-component regulator genes covRS. The emergence of M1UK is dated to 2008. Following a bottleneck coinciding with the COVID-19 pandemic, three emergent M1UK clades underwent rapid nationwide expansion, despite lack of detection in previous years. All M1UK isolates thus-far sequenced globally have a phylogenetic origin in the UK, with dispersal of the new clades in Europe. While waning immunity may promote streptococcal epidemics, the genetic features of M1UK point to a fitness advantage in pathogenicity, and a striking ability to persist through population bottlenecks.


COVID-19 , Phylogeny , Streptococcal Infections , Streptococcus pyogenes , Streptococcus pyogenes/genetics , Streptococcus pyogenes/pathogenicity , Streptococcus pyogenes/isolation & purification , United Kingdom/epidemiology , Humans , Streptococcal Infections/epidemiology , Streptococcal Infections/microbiology , COVID-19/epidemiology , Pandemics , Scarlet Fever/epidemiology , Scarlet Fever/microbiology , Mutation , Repressor Proteins/genetics , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , Genome, Bacterial , Europe/epidemiology , Bacterial Proteins
5.
Int J Mol Sci ; 25(9)2024 Apr 23.
Article En | MEDLINE | ID: mdl-38731837

Chromatin architecture is critical for the temporal and tissue-specific activation of genes that determine eukaryotic development. The functional interaction between enhancers and promoters is controlled by insulators and tethering elements that support specific long-distance interactions. However, the mechanisms of the formation and maintenance of long-range interactions between genome regulatory elements remain poorly understood, primarily due to the lack of convenient model systems. Drosophila became the first model organism in which architectural proteins that determine the activity of insulators were described. In Drosophila, one of the best-studied DNA-binding architectural proteins, Su(Hw), forms a complex with Mod(mdg4)-67.2 and CP190 proteins. Using a combination of CRISPR/Cas9 genome editing and attP-dependent integration technologies, we created a model system in which the promoters and enhancers of two reporter genes are separated by 28 kb. In this case, enhancers effectively stimulate reporter gene promoters in cis and trans only in the presence of artificial Su(Hw) binding sites (SBS), in both constructs. The expression of the mutant Su(Hw) protein, which cannot interact with CP190, and the mutation inactivating Mod(mdg4)-67.2, lead to the complete loss or significant weakening of enhancer-promoter interactions, respectively. The results indicate that the new model system effectively identifies the role of individual subunits of architectural protein complexes in forming and maintaining specific long-distance interactions in the D. melanogaster model.


Drosophila Proteins , Enhancer Elements, Genetic , Promoter Regions, Genetic , Drosophila Proteins/metabolism , Drosophila Proteins/genetics , Animals , Drosophila melanogaster/genetics , Drosophila melanogaster/metabolism , CRISPR-Cas Systems , DNA-Binding Proteins/metabolism , DNA-Binding Proteins/genetics , Chromatin/metabolism , Chromatin/genetics , Insulator Elements/genetics , Binding Sites , Protein Binding , Nuclear Proteins/metabolism , Nuclear Proteins/genetics , Gene Editing/methods , Repressor Proteins/metabolism , Repressor Proteins/genetics , Microtubule-Associated Proteins
6.
Proc Natl Acad Sci U S A ; 121(20): e2321711121, 2024 May 14.
Article En | MEDLINE | ID: mdl-38713624

During development, neural stem cells in the cerebral cortex, also known as radial glial cells (RGCs), generate excitatory neurons, followed by production of cortical macroglia and inhibitory neurons that migrate to the olfactory bulb (OB). Understanding the mechanisms for this lineage switch is fundamental for unraveling how proper numbers of diverse neuronal and glial cell types are controlled. We and others recently showed that Sonic Hedgehog (Shh) signaling promotes the cortical RGC lineage switch to generate cortical oligodendrocytes and OB interneurons. During this process, cortical RGCs generate intermediate progenitor cells that express critical gliogenesis genes Ascl1, Egfr, and Olig2. The increased Ascl1 expression and appearance of Egfr+ and Olig2+ cortical progenitors are concurrent with the switch from excitatory neurogenesis to gliogenesis and OB interneuron neurogenesis in the cortex. While Shh signaling promotes Olig2 expression in the developing spinal cord, the exact mechanism for this transcriptional regulation is not known. Furthermore, the transcriptional regulation of Olig2 and Egfr has not been explored. Here, we show that in cortical progenitor cells, multiple regulatory programs, including Pax6 and Gli3, prevent precocious expression of Olig2, a gene essential for production of cortical oligodendrocytes and astrocytes. We identify multiple enhancers that control Olig2 expression in cortical progenitors and show that the mechanisms for regulating Olig2 expression are conserved between the mouse and human. Our study reveals evolutionarily conserved regulatory logic controlling the lineage switch of cortical neural stem cells.


Basic Helix-Loop-Helix Transcription Factors , Cerebral Cortex , ErbB Receptors , Hedgehog Proteins , Nerve Tissue Proteins , Neural Stem Cells , Neurogenesis , Oligodendrocyte Transcription Factor 2 , PAX6 Transcription Factor , Animals , Neurogenesis/physiology , Cerebral Cortex/metabolism , Cerebral Cortex/cytology , Basic Helix-Loop-Helix Transcription Factors/metabolism , Basic Helix-Loop-Helix Transcription Factors/genetics , ErbB Receptors/metabolism , ErbB Receptors/genetics , Mice , Oligodendrocyte Transcription Factor 2/metabolism , Oligodendrocyte Transcription Factor 2/genetics , Nerve Tissue Proteins/metabolism , Nerve Tissue Proteins/genetics , Hedgehog Proteins/metabolism , Hedgehog Proteins/genetics , PAX6 Transcription Factor/metabolism , PAX6 Transcription Factor/genetics , Neural Stem Cells/metabolism , Neural Stem Cells/cytology , Homeodomain Proteins/metabolism , Homeodomain Proteins/genetics , Zinc Finger Protein Gli3/metabolism , Zinc Finger Protein Gli3/genetics , Eye Proteins/metabolism , Eye Proteins/genetics , Repressor Proteins/metabolism , Repressor Proteins/genetics , Paired Box Transcription Factors/metabolism , Paired Box Transcription Factors/genetics , Neuroglia/metabolism , Neuroglia/cytology , Gene Expression Regulation, Developmental , Signal Transduction , Olfactory Bulb/metabolism , Olfactory Bulb/cytology , Cell Lineage , Humans
7.
Front Immunol ; 15: 1293723, 2024.
Article En | MEDLINE | ID: mdl-38690263

T cells must adapt to variations in tissue microenvironments; these adaptations include the degree of oxygen availability. The hypoxia-inducible factor (HIF) transcription factors control much of this adaptation, and thus regulate many aspects of T cell activation and function. The HIFs are in turn regulated by oxygen-dependent hydroxylases: both the prolyl hydroxylases (PHDs) which interact with the VHL tumour suppressor and control HIF turnover, and the asparaginyl hydroxylase known as the Factor inhibiting HIF (FIH), which modulates HIF transcriptional activity. To determine the role of this latter factor in T cell function, we generated T cell-specific FIH knockout mice. We found that FIH regulates T cell fate and function in a HIF-dependent manner and show that the effects of FIH activity occur predominantly at physiological oxygen concentrations. T cell-specific loss of FIH boosts T cell cytotoxicity, augments T cell expansion in vivo, and improves anti-tumour immunotherapy in mice. Specifically inhibiting FIH in T cells may therefore represent a promising strategy for cancer immunotherapy.


Cell Differentiation , Mice, Knockout , Animals , Mice , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Repressor Proteins/genetics , Repressor Proteins/metabolism , Lymphocyte Activation/immunology , Mixed Function Oxygenases/genetics , Mixed Function Oxygenases/metabolism , Neoplasms/immunology , Neoplasms/metabolism , Mice, Inbred C57BL
8.
BMC Pediatr ; 24(1): 308, 2024 May 06.
Article En | MEDLINE | ID: mdl-38711055

BACKGROUND: ASXL3-related disorder, first described in 2013, is a genetic disorder with an autosomal dominant inheritance that is caused by a heterozygous loss-of-function variant in ASXL3. The most characteristic feature is neurodevelopmental delay with consistently limited speech. Feeding difficulty is a main symptom observed in infancy. However, no adolescent case has been reported. CASE PRESENTATION: A 14-year-old girl with ASXL3-related syndrome was referred to our hospital with subacute onset of emotional lability. Limbic encephalitis was ruled out by examination; however, the patient gradually showed a lack of interest in eating, with decreased diet volume. Consequently, she experienced significant weight loss. She experienced no symptoms of bulimia, or food allergy; therefore, avoidant/restrictive food intake disorder (ARFID) was clinically suspected. CONCLUSIONS: We reported the first case of ASXL3-related disorder with adolescent onset of feeding difficulty. ARFID was considered a cause of the feeding difficulty.


Abnormalities, Multiple , Facies , Feeding and Eating Disorders , Neurodevelopmental Disorders , Humans , Female , Adolescent , Feeding and Eating Disorders/etiology , Feeding and Eating Disorders/complications , Feeding and Eating Disorders/diagnosis , Repressor Proteins/genetics
9.
CNS Neurosci Ther ; 30(5): e14683, 2024 05.
Article En | MEDLINE | ID: mdl-38738952

INTRODUCTION: Alzheimer's disease (AD) and atherosclerosis (AS) are widespread diseases predominantly observed in the elderly population. Despite their prevalence, the underlying molecular interconnections between these two conditions are not well understood. METHODS: Utilizing meta-analysis, bioinformatics methodologies, and the GEO database, we systematically analyzed transcriptome data to pinpoint key genes concurrently differentially expressed in AD and AS. Our experimental validations in mouse models highlighted the prominence of two genes, NKRF (NF-κB-repressing factor) and ZBTB17 (MYC-interacting zinc-finger protein 1). RESULTS: These genes appear to influence the progression of both AD and AS by modulating the NF-κB signaling pathway, as confirmed through subsequent in vitro and in vivo studies. CONCLUSIONS: This research uncovers a novel shared molecular pathway between AD and AS, underscoring the significant roles of NKRF and ZBTB17 in the pathogenesis of these disorders.


Alzheimer Disease , Atherosclerosis , NF-kappa B , Signal Transduction , Alzheimer Disease/genetics , Alzheimer Disease/metabolism , Humans , Animals , Signal Transduction/genetics , Signal Transduction/physiology , NF-kappa B/metabolism , NF-kappa B/genetics , Atherosclerosis/genetics , Atherosclerosis/metabolism , Mice , Transcriptome , Gene Expression Profiling , Repressor Proteins/genetics , Repressor Proteins/metabolism , Mice, Transgenic
10.
Acta Neuropathol Commun ; 12(1): 72, 2024 May 06.
Article En | MEDLINE | ID: mdl-38711090

The RE1-silencing transcription factor (REST) acts either as a repressor or activator of transcription depending on the genomic and cellular context. REST is a key player in brain cell differentiation by inducing chromatin modifications, including DNA methylation, in a proximity of its binding sites. Its dysfunction may contribute to oncogenesis. Mutations in IDH1/2 significantly change the epigenome contributing to blockade of cell differentiation and glioma development. We aimed at defining how REST modulates gene activation and repression in the context of the IDH mutation-related phenotype in gliomas. We studied the effects of REST knockdown, genome wide occurrence of REST binding sites, and DNA methylation of REST motifs in IDH wild type and IDH mutant gliomas. We found that REST target genes, REST binding patterns, and TF motif occurrence proximal to REST binding sites differed in IDH wild-type and mutant gliomas. Among differentially expressed REST targets were genes involved in glial cell differentiation and extracellular matrix organization, some of which were differentially methylated at promoters or gene bodies. REST knockdown differently impacted invasion of the parental or IDH1 mutant glioma cells. The canonical REST-repressed gene targets showed significant correlation with the GBM NPC-like cellular state. Interestingly, results of REST or KAISO silencing suggested the interplay between these TFs in regulation of REST-activated and repressed targets. The identified gene regulatory networks and putative REST cooperativity with other TFs, such as KAISO, show distinct REST target regulatory networks in IDH-WT and IDH-MUT gliomas, without concomitant DNA methylation changes. We conclude that REST could be an important therapeutic target in gliomas.


Brain Neoplasms , DNA Methylation , Gene Regulatory Networks , Glioma , Isocitrate Dehydrogenase , Mutation , Isocitrate Dehydrogenase/genetics , Glioma/genetics , Glioma/pathology , Glioma/metabolism , Humans , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Brain Neoplasms/metabolism , Cell Line, Tumor , Repressor Proteins/genetics , Repressor Proteins/metabolism , Gene Expression Regulation, Neoplastic/genetics
11.
PLoS One ; 19(5): e0300751, 2024.
Article En | MEDLINE | ID: mdl-38717999

Transcriptional response to changes in oxygen concentration is mainly controlled by hypoxia-inducible transcription factors (HIFs). Besides regulation of hypoxia-responsible gene expression, HIF-3α has recently been shown to be involved in lung development and in the metabolic process of fat tissue. However, the precise mechanism for such properties of HIF-3α is still largely unknown. To this end, we generated HIF3A gene-disrupted mice by means of genome editing technology to explore the pleiotropic role of HIF-3α in development and physiology. We obtained adult mice carrying homozygous HIF3A gene mutations with comparable body weight and height to wild-type mice. However, the number of litters and ratio of homozygous mutation carriers born from the mating between homozygous mutant mice was lower than expected due to sporadic deaths on postnatal day 1. HIF3A gene-disrupted mice exhibited abnormal configuration of the lung such as a reduced number of alveoli and thickened alveolar walls. Transcriptome analysis showed, as well as genes associated with lung development, an upregulation of stearoyl-Coenzyme A desaturase 1, a pivotal enzyme for fatty acid metabolism. Analysis of fatty acid composition in the lung employing gas chromatography indicated an elevation in palmitoleic acid and a reduction in oleic acid, suggesting an imbalance in distribution of fatty acid, a constituent of lung surfactant. Accordingly, administration of glucocorticoid injections during pregnancy resulted in a restoration of normal alveolar counts and a decrease in neonatal mortality. In conclusion, these observations provide novel insights into a pivotal role of HIF-3α in the preservation of critically important structure and function of alveoli beyond the regulation of hypoxia-mediated gene expression.


Animals, Newborn , Pulmonary Alveoli , Animals , Mice , Pulmonary Alveoli/metabolism , Pulmonary Alveoli/pathology , Female , Repressor Proteins/genetics , Repressor Proteins/metabolism , Aryl Hydrocarbon Receptor Nuclear Translocator/genetics , Aryl Hydrocarbon Receptor Nuclear Translocator/metabolism , Male , Fatty Acids/metabolism , Stearoyl-CoA Desaturase/genetics , Stearoyl-CoA Desaturase/metabolism , Apoptosis Regulatory Proteins
12.
J Cell Biol ; 223(8)2024 Aug 05.
Article En | MEDLINE | ID: mdl-38709169

Histone H3 lysine36 dimethylation (H3K36me2) is generally distributed in the gene body and euchromatic intergenic regions. However, we found that H3K36me2 is enriched in pericentromeric heterochromatin in some mouse cell lines. We here revealed the mechanism of heterochromatin targeting of H3K36me2. Among several H3K36 methyltransferases, NSD2 was responsible for inducing heterochromatic H3K36me2. Depletion and overexpression analyses of NSD2-associating proteins revealed that NSD2 recruitment to heterochromatin was mediated through the imitation switch (ISWI) chromatin remodeling complexes, such as BAZ1B-SMARCA5 (WICH), which directly binds to AT-rich DNA via a BAZ1B domain-containing AT-hook-like motifs. The abundance and stoichiometry of NSD2, SMARCA5, and BAZ1B could determine the localization of H3K36me2 in different cell types. In mouse embryos, H3K36me2 heterochromatin localization was observed at the two- to four-cell stages, suggesting its physiological relevance.


Chromatin Assembly and Disassembly , Heterochromatin , Histone-Lysine N-Methyltransferase , Histones , Repressor Proteins , Animals , Humans , Mice , Adenosine Triphosphatases , Bromodomain Containing Proteins/genetics , Bromodomain Containing Proteins/metabolism , Centromere/metabolism , Centromere/genetics , Chromosomal Proteins, Non-Histone/metabolism , Chromosomal Proteins, Non-Histone/genetics , Heterochromatin/metabolism , Heterochromatin/genetics , Histone-Lysine N-Methyltransferase/metabolism , Histone-Lysine N-Methyltransferase/genetics , Histones/metabolism , Histones/genetics , Methylation , Repressor Proteins/metabolism , Repressor Proteins/genetics , Transcription Factors/metabolism , Transcription Factors/genetics
13.
Prep Biochem Biotechnol ; 54(5): 709-719, 2024 May.
Article En | MEDLINE | ID: mdl-38692288

Identification of a single genetic target for microbial strain improvement is difficult due to the complexity of the genetic regulatory network. Hence, a more practical approach is to identify bottlenecks in the regulatory networks that control critical metabolic pathways. The present work focuses on enhancing cellular physiology by increasing the metabolic flux through the central carbon metabolic pathway. Global regulator cra (catabolite repressor activator), a DNA-binding transcriptional dual regulator was selected for the study as it controls the expression of a large number of operons that modulate central carbon metabolism. To upregulate the activity of central carbon metabolism, the cra gene was co-expressed using a plasmid-based system. Co-expression of cra led to a 17% increase in the production of model recombinant protein L-Asparaginase-II. A pulse addition of 0.36% of glycerol every two hours post-induction, further increased the production of L-Asparaginase-II by 35% as compared to the control strain expressing only recombinant protein. This work exemplifies that upregulating the activity of central carbon metabolism by tuning the expression of regulatory genes like cra can relieve the host from cellular stress and thereby promote the growth as well as expression of recombinant hosts.


Asparaginase , Escherichia coli , Recombinant Proteins , Asparaginase/genetics , Asparaginase/metabolism , Asparaginase/biosynthesis , Escherichia coli/genetics , Escherichia coli/metabolism , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Repressor Proteins/genetics , Repressor Proteins/metabolism , Glycerol/metabolism , Gene Expression Regulation, Bacterial
14.
BMC Genomics ; 25(1): 441, 2024 May 03.
Article En | MEDLINE | ID: mdl-38702600

BACKGROUND: Quorum sensing (QS) is a sophisticated cell-to-cell signalling mechanism that allows the coordination of important processes in microbial populations. The AI-1 and AI-2 autoinducer systems are among the best characterized bacterial QS systems at the genetic level. RESULTS: In this study, we present data derived from in silico screening of QS proteins from bacterial genomes available in public databases. Sequence analyses allowed identifying candidate sequences of known QS systems that were used to build phylogenetic trees. Eight categories were established according to the number of genes from the two major QS systems present in each genome, revealing a correlation with specific taxa, lifestyles or metabolic traits. Many species had incomplete QS systems, encoding the receptor protein but not the biosynthesis of the quorum sensing molecule (QSMs). Reconstruction of the evolutionary history of the LuxR family and prediction of the 3D structure of the ancestral protein suggested their monomeric configuration in the absence of the signal molecule and the presence of a cavity for its binding. CONCLUSIONS: Here we correlate the taxonomic affiliation and lifestyle of bacteria from different genera with the QS systems encoded in their genomes. Moreover, we present the first ancestral reconstruction of the LuxR QS receptors, providing further insight in their evolutionary history.


Bacteria , Bacterial Proteins , Evolution, Molecular , Phylogeny , Quorum Sensing , Quorum Sensing/genetics , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Bacteria/genetics , Bacteria/metabolism , Genome, Bacterial , Trans-Activators/genetics , Trans-Activators/metabolism , Trans-Activators/chemistry , Repressor Proteins/genetics , Repressor Proteins/metabolism
15.
Breast Cancer Res ; 26(1): 74, 2024 May 03.
Article En | MEDLINE | ID: mdl-38702730

The transcription factor TRPS1 is a context-dependent oncogene in breast cancer. In the mammary gland, TRPS1 activity is restricted to the luminal population and is critical during puberty and pregnancy. Its function in the resting state remains however unclear. To evaluate whether it could be a target for cancer therapy, we investigated TRPS1 function in the healthy adult mammary gland using a conditional ubiquitous depletion mouse model where long-term depletion does not affect fitness. Using transcriptomic approaches, flow cytometry and functional assays, we show that TRPS1 activity is essential to maintain a functional luminal progenitor compartment. This requires the repression of both YAP/TAZ and SRF/MRTF activities. TRPS1 represses SRF/MRTF activity indirectly by modulating RhoA activity. Our work uncovers a hitherto undisclosed function of TRPS1 in luminal progenitors intrinsically linked to mechanotransduction in the mammary gland. It may also provide new insights into the oncogenic functions of TRPS1 as luminal progenitors are likely the cells of origin of many breast cancers.


Mammary Glands, Animal , Repressor Proteins , Serum Response Factor , Stem Cells , Transcription Factors , Animals , Female , Mice , Mammary Glands, Animal/metabolism , Mammary Glands, Animal/cytology , Transcription Factors/metabolism , Transcription Factors/genetics , Stem Cells/metabolism , Repressor Proteins/metabolism , Repressor Proteins/genetics , Serum Response Factor/metabolism , Serum Response Factor/genetics , Humans , Trans-Activators/metabolism , Trans-Activators/genetics
16.
J Am Coll Cardiol ; 83(18): 1717-1727, 2024 May 07.
Article En | MEDLINE | ID: mdl-38692825

BACKGROUND: The expansion of hematopoietic stem cells caused by acquired somatic mutations (clonal hematopoiesis [CH]) is a novel cardiovascular risk factor. The prognostic value of CH in patients with carotid atherosclerosis remains to be evaluated. OBJECTIVES: This study assessed the prognostic significance of CH in patients with atherosclerosis as detected by ultrasound of the carotid artery. METHODS: We applied deep sequencing of selected genomic regions within the genes DNMT3A, TET2, ASXL1, and JAK2 to screen for CH in 968 prospectively collected patients with asymptomatic carotid atherosclerosis evaluated by duplex sonography. RESULTS: We detected clonal markers at variant allele frequency ≥2% in 133 (13.7%) of 968 patients (median age 69.2 years), with increasing prevalence at advanced age. Multivariate analyses including age and established cardiovascular risk factors revealed overall presence of CH to be significantly associated with increased risk of cardiovascular death (HR: 1.50; 95% CI: 1.12-2.00; P = 0.007), reflected also at the single gene level. The effect of CH was more pronounced in older patients and independent of the patients' inflammatory status as measured by high-sensitivity C-reactive protein. Simultaneous assessment of CH and degree of carotid stenosis revealed combined effects on cardiovascular mortality, depicted by a superior risk for patients with >50% stenosis and concomitant CH (adjusted HR: 1.60; 95% CI: 1.08-2.38; P = 0.020). CONCLUSIONS: CH status in combination with the extent of carotid atherosclerosis jointly predict long-term mortality. Determination of CH can provide additional prognostic information in patients with asymptomatic carotid atherosclerosis.


Carotid Stenosis , Clonal Hematopoiesis , Janus Kinase 2 , Humans , Male , Female , Aged , Clonal Hematopoiesis/genetics , Carotid Stenosis/genetics , Carotid Stenosis/complications , Carotid Stenosis/diagnostic imaging , Middle Aged , DNA Methyltransferase 3A , Dioxygenases , Prospective Studies , DNA-Binding Proteins/genetics , Repressor Proteins/genetics , Proto-Oncogene Proteins/genetics , Prognosis , Cardiovascular Diseases/genetics , Cardiovascular Diseases/mortality , DNA (Cytosine-5-)-Methyltransferases/genetics
17.
FASEB J ; 38(9): e23640, 2024 May 15.
Article En | MEDLINE | ID: mdl-38690715

Osteoarthritis (OA) is the main cause of cartilage damage and disability. This study explored the biological function of S-phase kinase-associated protein 2 (SKP2) and Kruppel-like factor 11 (KLF11) in OA progression and its underlying mechanisms. C28/I2 chondrocytes were stimulated with IL-1ß to mimic OA in vitro. We found that SKP2, Jumonji domain-containing protein D3 (JMJD3), and Notch receptor 1 (NOTCH1) were upregulated, while KLF11 was downregulated in IL-1ß-stimulated chondrocytes. SKP2/JMJD3 silencing or KLF11 overexpression repressed apoptosis and extracellular matrix (ECM) degradation in chondrocytes. Mechanistically, SKP2 triggered the ubiquitination and degradation of KLF11 to transcriptionally activate JMJD3, which resulted in activation of NOTCH1 through inhibiting H3K27me3. What's more, the in vivo study found that KLF11 overexpression delayed OA development in rats via restraining apoptosis and maintaining the balance of ECM metabolism. Taken together, ubiquitination and degradation of KLF11 regulated by SKP2 contributed to OA progression by activation of JMJD3/NOTCH1 pathway. Our findings provide promising therapeutic targets for OA.


Chondrocytes , Jumonji Domain-Containing Histone Demethylases , Osteoarthritis , Receptor, Notch1 , S-Phase Kinase-Associated Proteins , Ubiquitination , Receptor, Notch1/metabolism , Receptor, Notch1/genetics , Animals , S-Phase Kinase-Associated Proteins/metabolism , S-Phase Kinase-Associated Proteins/genetics , Osteoarthritis/metabolism , Osteoarthritis/pathology , Osteoarthritis/genetics , Rats , Chondrocytes/metabolism , Chondrocytes/pathology , Jumonji Domain-Containing Histone Demethylases/metabolism , Jumonji Domain-Containing Histone Demethylases/genetics , Male , Signal Transduction , Rats, Sprague-Dawley , Humans , Apoptosis , Repressor Proteins/metabolism , Repressor Proteins/genetics , Kruppel-Like Transcription Factors/metabolism , Kruppel-Like Transcription Factors/genetics
18.
J Genet ; 1032024.
Article En | MEDLINE | ID: mdl-38736250

In acute lymphoblastic leukaemia (ALL), elevated foetal haemoglobin (HbF) levels have been associated with the prognosis of patients. Genetic variants in HbF regulatory genes: BAF chromatin remodelling complex subunit (BCL11A), HBS1L-MYB transcriptional GTPase intergenic region (HBS1L-MYB), Krüppel-like factor 1 (KLF1), haemoglobin gamma subunit 2 (HBG2), haemoglobin gamma subunit 1 (HBG1), and haemoglobin subunit beta pseudogene 1 (HBBP1) are often associatedwith elevatedHbF concentration. This study investigated the association of genetic variants in HbF regulatory genes with HbF concentration, unfavourable prognosis, and outcome in children with ALL.We quantified HbF concentration and genotyped 17 genetic variants in 48 patients with ALL and 64 children without ALL as a reference group. HbF concentrationwas higher in patients than in the reference group (4.4%vs 1.4%), and 75%(n = 36) of thepatientshadHbF>2.5%.Unfavourable prognosis ALL was established in 68.8% (n = 33) of the patients. Variant HBG2 rs7482144 was associated with high HbF concentration (P = 0.015); while HBS1L-MYB rs9399137 (P = 0.001), HBG2 rs7482144 (P = 0.001) and the ß-globin genes HBG2, HBG1, and HBPP1 haplotypeTGC(P = 0.017) with unfavourable prognosisALL.Additionally, variantBCL11A rs4671393 showed a protective role (P = 0.0001). In conclusion, variants HBG2 rs7482144, HBS1L-MYB rs9399137 and BCL11A rs4671393 may play a significant role in ALL.


Fetal Hemoglobin , Polymorphism, Single Nucleotide , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Repressor Proteins , Humans , Fetal Hemoglobin/genetics , Female , Male , Child , Prognosis , Repressor Proteins/genetics , Child, Preschool , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Infant , Nuclear Proteins/genetics , Proto-Oncogene Proteins c-myb/genetics , Carrier Proteins/genetics , Adolescent , Genotype , gamma-Globins/genetics , GTP-Binding Proteins
19.
Sci Adv ; 10(18): eadm7039, 2024 May 03.
Article En | MEDLINE | ID: mdl-38701209

Long-range glutamatergic inputs originating from the cortex and thalamus are indispensable for striatal development, providing the foundation for motor and cognitive functions. Despite their significance, transcriptional regulation governing these inputs remains largely unknown. We investigated the role of a transcription factor encoded by a high-risk autism-associated gene, FOXP1, in sculpting glutamatergic inputs onto spiny projection neurons (SPNs) within the striatum. We find a neuron subtype-specific role of FOXP1 in strengthening and maturing glutamatergic inputs onto dopamine receptor 2-expressing SPNs (D2 SPNs). We also find that FOXP1 promotes synaptically driven excitability in these neurons. Using single-nuclei RNA sequencing, we identify candidate genes that mediate these cell-autonomous processes through postnatal FOXP1 function at the post-synapse. Last, we demonstrate that postnatal FOXP1 reinstatement rescues electrophysiological deficits, cell type-specific gene expression changes, and behavioral phenotypes. Together, this study enhances our understanding of striatal circuit development and provides proof of concept for a therapeutic approach for FOXP1 syndrome and other neurodevelopmental disorders.


Corpus Striatum , Forkhead Transcription Factors , Neurons , Receptors, Dopamine D2 , Repressor Proteins , Animals , Forkhead Transcription Factors/metabolism , Forkhead Transcription Factors/genetics , Corpus Striatum/metabolism , Corpus Striatum/cytology , Mice , Neurons/metabolism , Repressor Proteins/metabolism , Repressor Proteins/genetics , Phenotype , Synapses/metabolism , Synapses/physiology , Male
20.
J Mol Biol ; 436(10): 168573, 2024 May 15.
Article En | MEDLINE | ID: mdl-38626867

Iron homeostasis is a critical process for living organisms because this metal is an essential co-factor for fundamental biochemical activities, like energy production and detoxification, albeit its excess quickly leads to cell intoxication. The protein Fur (ferric uptake regulator) controls iron homeostasis in bacteria by switching from its apo- to holo-form as a function of the cytoplasmic level of ferrous ions, thereby modulating gene expression. The Helicobacter pylori HpFur protein has the rare ability to operate as a transcriptional commutator; apo- and holo-HpFur function as two different repressors with distinct DNA binding recognition properties for specific sets of target genes. Although the regulation of apo- and holo-HpFur in this bacterium has been extensively investigated, we propose a genome-wide redefinition of holo-HpFur direct regulon in H. pylori by integration of RNA-seq and ChIP-seq data, and a large extension of the apo-HpFur direct regulon. We show that in response to iron availability, new coding sequences, non-coding RNAs, toxin-antitoxin systems, and transcripts within open reading frames are directly regulated by apo- or holo-HpFur. These new targets and the more thorough validation and deeper characterization of those already known provide a complete and updated picture of the direct regulons of this two-faced transcriptional regulator.


Bacterial Proteins , Gene Expression Regulation, Bacterial , Helicobacter pylori , Iron , Regulon , Repressor Proteins , Helicobacter pylori/genetics , Helicobacter pylori/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Iron/metabolism , Regulon/genetics , Repressor Proteins/genetics , Repressor Proteins/metabolism
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