Overexpression Of Transcription Factor Research Articles

Overexpression of anthocyanin regulatory transcription factors can alleviate salt stress-induced growth inhibition in torenia ‘Kauai Rose’

Overexpression of anthocyanin regulatory transcription factors can alleviate salt stress-induced growth inhibition in torenia ‘Kauai Rose’

Netrin-1 mediates nerve innervation and angiogenesis leading to discogenic pain.

Discogenic low back pain (LBP) is associated with nociceptive nerve fibers that grow into degenerated intervertebral discs (IVD) but the etiopathogenesis of disease is not fully understood. The purpose of this study was to clarify the role of Netrin-1 in causing discogenic LBP. The level of nociceptive nerve innervation was examined in disc degenerative patients and rat needle-punctured models by immunohistochemistry. Nucleus pulposus (NP) cells were isolated from IVD tissues of rats and induced degeneration by interleukin-1β (IL-1β) or tumor necrosis factor α (TNFα). The candidate genes related to neuron outgrowth and migration were selected by Next-generation sequencing (NGS). CRISPR/Cas9 was used to knockdown Netrin-1 in NP cells. The impact of Netrin-1 on nerve innervation were evaluated with P2X2、NF200 staining and microfluidics assay. Meanwhile the CD31 staining and transwell assay were used to evaluate the impact of Netrin-1 in angiogenesis. The proteins and RNA extracted from NP cells related to catabolism and anabolism were examined by western blot assay and RT-qPCR experiment. ChIP and luciferase experiments were used to assess the intracellular transcriptional regulation of Netrin-1. Further, a needle-punctured rat model followed by histomorphometry and immunofluorescence histochemistry was used to explore the potential effect of Netrin-1 on LBP in vivo. The level of nerve innervation was increased in severe disc degenerative patients while the expression of Netrin-1 was upregulated. The supernatants of NP cells stimulated with IL-1β or TNFα containing more Netrin-1 could promote axon growth and vascular endothelial cells migration. Knocking down Netrin-1 or overexpressing transcription factor TCF3 as a negative regulator of Netrin-1 attenuated this effect. The needle-punctured rat model brought significant spinal hypersensitivity, nerve innervation and angiogenesis, nevertheless knocking down Netrin-1 effectively prevented disc degeneration-induced adverse impacts. Discogenic LBP was induced by Netrin-1, which mediated nerve innervation and angiogenesis in disc degeneration. Knocking down Netrin-1 by CRISPR/Cas9 or negatively regulating Netrin1 by transcription factor TCF3 could alleviate spinal hypersensitivity. This study on Netrin-1 could provide a new target and theoretical basis for the prevention and treatment for discogenic back pain.

Addressing Transcriptional Dysregulation in Cancer through CDK9 Inhibition.

Undermining transcriptional addiction, the dependence of cancers on selected transcriptional programs, is critically important for addressing cancers with high unmet clinical need. Cyclin-dependent kinase 9 (CDK9) has long been considered an actionable therapeutic target for modulating transcription in many diseases. This appeal is due to its role in coordinating the biochemical events that regulate RNA polymerase II (RNA Pol II) pause-release state, one that offers a way for attenuating transcriptional dysregulation driven by amplified or overexpressed transcription factors implicated in cancer. However, targeting CDK9 in the clinic has historically proven elusive, a challenge that stems from the often highly intolerable cytotoxicity attributed to its essentiality across many cell lineages and the polypharmacology of the first generation of pan-CDK inhibitors to reach the clinic. A new wave of highly selective molecules progressing through the early stages of clinical evaluation offers renewed hope.

Directed differentiation of human iPSCs to functional ovarian granulosa-like cells via transcription factor overexpression.

An in vitro model of human ovarian follicles would greatly benefit the study of female reproduction. Ovarian development requires the combination of germ cells and several types of somatic cells. Among these, granulosa cells play a key role in follicle formation and support for oogenesis. Whereas efficient protocols exist for generating human primordial germ cell-like cells (hPGCLCs) from human induced pluripotent stem cells (hiPSCs), a method of generating granulosa cells has been elusive. Here, we report that simultaneous overexpression of two transcription factors (TFs) can direct the differentiation of hiPSCs to granulosa-like cells. We elucidate the regulatory effects of several granulosa-related TFs and establish that overexpression of NR5A1 and either RUNX1 or RUNX2 is sufficient to generate granulosa-like cells. Our granulosa-like cells have transcriptomes similar to human fetal ovarian cells and recapitulate key ovarian phenotypes including follicle formation and steroidogenesis. When aggregated with hPGCLCs, our cells form ovary-like organoids (ovaroids) and support hPGCLC development from the premigratory to the gonadal stage as measured by induction of DAZL expression. This model system will provide unique opportunities for studying human ovarian biology and may enable the development of therapies for female reproductive health.

The AP-1 transcription factor Fosl-2 drives cardiac fibrosis and arrhythmias under immunofibrotic conditions

Fibrotic changes in the myocardium and cardiac arrhythmias represent fatal complications in systemic sclerosis (SSc), however the underlying mechanisms remain elusive. Mice overexpressing transcription factor Fosl-2 (Fosl-2tg) represent animal model of SSc. Fosl-2tg mice showed interstitial cardiac fibrosis, disorganized connexin-43/40 in intercalated discs and deregulated expression of genes controlling conduction system, and developed higher heart rate (HR), prolonged QT intervals, arrhythmias with prevalence of premature ventricular contractions, ventricular tachycardias, II-degree atrio-ventricular blocks and reduced HR variability. Following stimulation with isoproterenol Fosl-2tg mice showed impaired HR response. In contrast to Fosl-2tg, immunodeficient Rag2−/−Fosl-2tg mice were protected from enhanced myocardial fibrosis and ECG abnormalities. Transcriptomics analysis demonstrated that Fosl-2-overexpression was responsible for profibrotic signature of cardiac fibroblasts, whereas inflammatory component in Fosl-2tg mice activated their fibrotic and arrhythmogenic phenotype. In human cardiac fibroblasts FOSL-2-overexpression enhanced myofibroblast signature under proinflammatory or profibrotic stimuli. These results demonstrate that under immunofibrotic conditions transcription factor Fosl-2 exaggerates myocardial fibrosis, arrhythmias and aberrant response to stress.

HWJMSC-derived extracellular vesicles ameliorate IL-1β-induced chondrocyte injury through regulation of the BMP2/RUNX2 axis via up-regulation TFRC

Articular osteochondral injury is a common and frequently occurring disease in orthopedics that is caused by aging, disease, and trauma. The cytokine interleukin-1β (IL-1β) is a crucial mediator of the inflammatory response, which exacerbates damage during chronic disease and acute tissue injury. Human Wharton's jelly mesenchymal stem cell (HWJMSC) extracellular vesicles (HWJMSC-EVs) have been shown to promote cartilage regeneration. The study aimed to investigate the influence and mechanisms of HWJMSC-EVs on the viability, apoptosis, and cell cycle of IL-1β-induced chondrocytes. HWJMSC-EVs were isolated by Ribo™ Exosome Isolation Reagent kit. Nanoparticle tracking analysis was used to determine the size and concentration of HWJMSC-EVs. We characterized HWJMSC-EVs by western blot and transmission electron microscope. The differentiation, viability, and protein level of chondrocytes were measured by Alcian blue staining, Cell Counting Kit-8, and western blot, respectively. Flow cytometer was used to determine apoptosis and cell cycle of chondrocytes. The results showed that HWJMSCs relieved IL-1β-induced chondrocyte injury by inhibiting apoptosis and elevating viability and cell cycle of chondrocyte, which was reversed with exosome inhibitor (GW4869). HWJMSC-EVs were successfully extracted and proven to be uptake by chondrocytes. HWJMSC-EVs ameliorate IL-1β-induced chondrocyte injury by inhibiting cell apoptosis and elevating viability and cycle of cell, but these effects were effectively reversed by knockdown of transferrin receptor (TFRC). Notably, using bone morphogenetic protein 2 (BMP2) pathway agonist and inhibitor suggested that HWJMSC-EVs ameliorate IL-1β-induced chondrocyte injury through activating the BMP2 pathway via up-regulation TFRC. Furthermore, over-expression of runt-related transcription factor 2 (RUNX2) reversed the effects of BMP2 pathway inhibitor promotion of IL-1β-induced chondrocyte injury. These results suggested that HWJMSC-EVs ameliorate IL-1β-induced chondrocyte injury by regulating the BMP2/RUNX2 axis via up-regulation TFRC. HWJMSC-EVs may play a new insight for early medical interventions in patients with articular osteochondral injury.

Drought-induced CsMYB6 interacts with CsbHLH111 to regulate anthocyanin biosynthesis in Chaenomeles speciosa.

Chaenomeles speciosa is a plant with high ornamental value, and the color of its petals deepens obviously under drought stress. To understand the mechanism of drought-induced reddening of C. speciosa petal color, the metabolites and transcriptomics of petals from 4% PEG-8000-treated and control cuttings were analyzed. In this study, the analysis of metabolites revealed the accumulation of anthocyanins in petals of PEG-treated cuttings, indicating anthocyanins might be the reason for the deepening of petal color. By using transcriptomics, we identified CsMYB6 as an overexpressed transcription factor in PEG-treated samples. Transient overexpression and suppression of CsMYB6 revealed that it is a key transcription factor for anthocyanin synthesis. We identified genes related to anthocyanin biosynthesis and constructed a network of drought- and anthocyanin-related genes (such as CsMYB6, CsbHLH111, CsANS, CsDFR, and CsUFGT). Further experiments indicated that CsMYB6 directly interacted with CsbHLH111, and this interaction increased the binding ability of CsMYB6 to the promoter regions of three structural genes of anthocyanin biosynthesis: CsANS, CsDFR, and CsUFGT. Our findings provide a molecular basis and new insight into drought-induced anthocyanin biosynthesis in C. speciosa.

Unique Characteristics of Neonatal T Cells

Birth causes complex changes in the individual physiology and organ systems and certainly poses a big immune challenge. The sudden encounter with an antigen full world, with the exposure to food antigens, and the colonization of the skin and mucosa with microbiota, require a tolerant immune system. Nevertheless, neonates must also be able to deal with pathogens, which makes their immune system unique. T lymphocytes are responsible for the coordination of the adaptive immune system response, the elimination of infected cells and the type of immune response and memory. It has been shown that neonatal cells have intrinsic differences with adult cells, biased towards an innate response and a tolerant phenotype. In the perinatal period, the immune system changes from basal signaling and innate like responses, towards stimulus-specific signals, which increase with gestational age. After birth the cells of the immune system continue to change both in composition and function. In this review, we present the intrinsic differences of neonatal CD4+ and CD8+ T cells, as compared with adult naïve cells. A specific transcriptome profile is present in both CD4+ and CD8+ neonatal T cells, with overexpression of homeobox transcription factors. These cells also present differences in cell signaling and metabolic characteristics, which result in unique functional capabilities. Neonatal CD4+ T cells respond differently from adult cells, with a high production of IL-8, a prevalent Th2 over Th1 profile, and an innate inflammatory response. The neonatal period is one of the most vulnerable periods of life, with a high morbidity and mortality rate, approaching on average 17 deaths per 1000 live births worldwide. A better understanding of the neonatal immune system will help to ensure a better care of this vulnerable population.

Overexpression of the Arabidopsis SHN3 transcription factor compromises the rust disease resistance of transgenic switchgrass plants

Switchgrass can generate large amounts of renewable biomass and hence is one of the most promising bioenergy crops. Improving the quality of switchgrass lignocellulosic biomass will enable its utilization for biofuels. Arabidopsis SHINE family of transcription factor <italic>SHN2</italic> was previously identified as a master regulator of cell wall deposition in transgenic rice. However, it is unclear if the Arabidopsis <italic>SHN</italic> genes also have a similar biological function in switchgrass. Here, we generated transgenic switchgrass overexpressing the <italic>Arabidopsis</italic> <italic>SHN3</italic> transcription factor. Compared with the wild-type, <italic>AtSHN3</italic>-overexpressing switchgrass plants were stunted in their growth. There were no significant differences in terms of lignin and cellulose contents between the SHN transgenics and wild-type switchgrass plants. However, two <italic>AtSHN3</italic> transgenic lines SHN7-2 and SHN5-2, displayed significant changes in several matrix polysaccharide monomers. Overexpression of <italic>AtSHN3</italic> in switchgrass did not alter the stem mechanical strength when subjected to tensile-torsion analysis. Interestingly, the <italic>AtSHN3</italic>-overexpressing transgenic lines were more susceptible to switchgrass rust (<italic>Puccinia emaculata</italic>) than wild-type plants. Therefore, AtSHN3 may have a negative role in regulating disease resistance in switchgrass.

Gene regulatory network reconfiguration in direct lineage reprogramming.

In direct lineage conversion, transcription factor (TF) overexpression reconfigures gene regulatory networks (GRNs) to reprogram cell identity. We previously developed CellOracle, a computational method to infer GRNs from single-cell transcriptome and epigenome data. Using inferred GRNs, CellOracle simulates gene expression changes in response to TF perturbation, enabling in silico interrogation of network reconfiguration. Here, we combine CellOracle analysis with lineage tracing of fibroblast to induced endoderm progenitor (iEP) conversion, a prototypical direct reprogramming paradigm. By linking early network state to reprogramming outcome, we reveal distinct network configurations underlying successful and failed fate conversion. Via in silico simulation of TF perturbation, we identify new factors to coax cells into successfully converting their identity, uncovering a central role for the AP-1 subunit Fos with the Hippo signaling effector, Yap1. Together, these results demonstrate the efficacy of CellOracle to infer and interpret cell-type-specific GRN configurations, providing new mechanistic insights into lineage reprogramming.

A transcription factor atlas of directed differentiation

Transcription factors (TFs) regulate gene programs, thereby controlling diverse cellular processes and cell states. To comprehensively understand TFs and the programs they control, we created a barcoded library of all annotated human TF splice isoforms (>3,500) and applied it to build a TF Atlas charting expression profiles of human embryonic stem cells (hESCs) overexpressing each TF at single-cell resolution. We mapped TF-induced expression profiles to reference cell types and validated candidate TFs for generation of diverse cell types, spanning all three germ layers and trophoblasts. Targeted screens with subsets of the library allowed us to create a tailored cellular disease model and integrate mRNA expression and chromatin accessibility data to identify downstream regulators. Finally, we characterized the effects of combinatorial TF overexpression by developing and validating a strategy for predicting combinations of TFs that produce target expression profiles matching reference cell types to accelerate cellular engineering efforts.

PUB30-mediated downregulation of the HB24-SWEET11 module is involved in root growth inhibition under salt stress by attenuating sucrose supply in Arabidopsis.

One of the strategies that plants adopt to cope with an unfavorable environment is to sacrifice their growth for tolerance. Although moderate salt stress can induce root growth inhibition, the molecular mechanisms regulating this process have yet to be elucidated. Here, we found that overexpression of a zinc finger-homeodomain family transcription factor, HOMEOBOX PROTEIN 24 (HB24), led to longer primary roots than in the wild-type in the presence of 125 mM NaCl, whereas this phenotype was reversed for the hb24 loss-of-function mutant, indicating a negative impact of HB24 on salt-induced root growth inhibition. We then found that salt stress triggered the degradation of HB24 via the ubiquitin-proteasome pathway, as mediated by a plant U-box type E3 ubiquitin ligase 30 (PUB30) that directly targets HB24. We verified that HB24 is able to directly bind to the promoters of Sugars Will Eventually be Exported Transporter 11/12 (SWEET11/12) to regulate their expression in roots. Through genetic and biochemical assays, we further demonstrated that the HB24-SWEET11 module plays a negative role in salt-induced root growth inhibition. Therefore, we propose that under salt stress, PUB30 mediates HB24's degradation, thereby downregulating the expression of SWEET11, resulting in reduced sucrose supply and root growth inhibition.

SOX2-high cancer cells exhibit an aggressive phenotype, with increases in stemness, proliferation and invasion, as well as higher metabolic activity and ATP production.

Cancer stem cells (CSCs) are responsible for cancer recurrence, treatment failure and metastatic dissemination. As such, the elimination of CSCs represents one of the most important approaches for the future of cancer treatment. Among other properties, CSCs show the activation of particular cell signalling pathways and the over-expression of certain transcription factors, such as SOX2. Herein, we describe a new model system to isolate stem-like cancer cells, based on the functional transcriptional activity of SOX2. Briefly, we employed a SOX2-enhancer-GFP-reporter system to isolate cancer cells with high SOX2 transcriptional activity by FACS sorting. The over-expression of SOX2 in this sub-population was validated by Western blot analysis and flow cytometry. SOX2-high cancer cells showed CSCs features, such as greater mammosphere forming ability, validating that this sub-population was enriched in CSCs. To further explore the model, we analysed other stemness characteristics in MCF7 and MDA-MB-231 breast cancer cell lines, corroborating that SOX2-high cells were more metabolically active, proliferative, migratory, invasive, and drug-resistant. SOX2-high MDA-MB-231 cells also showed a loss of E-cadherin expression, and increased Vimentin expression, consistent with an epithelial-mesenchymal transition (EMT). Therefore, endogenous SOX2 transcriptional activity and protein levels are mechanistically linked to aggressive phenotypic behaviours and energy production in CSCs.

PROTEOSTASIS: NOVEL INSIGHTS AND TECHNOLOGIES

Abstract Skeletal muscle has recently arisen as a novel regulators of Central Nervous System (CNS) function and aging, secreting bioactive molecules known as myokines with proteostasis and metabolism-modifying functions in targeted tissues, including the CNS. Myokine secretion is heavily modified by exercise, suggesting that myokine signaling in the periphery may underlie the well document geroprotective benefits of exercise on the brain. The following studies address muscle proteostasis, a pathway highly activated during exercise, as a potential new regulator of the neurocognitive benefits of exercise. We have recently generated a novel transgenic mouse with enhanced muscle proteostasis via moderate overexpression of Transcription Factor E-B (TFEB), a powerful master regulator of cellular clearance and proteostasis. We have discovered that the resulting enhanced skeletal muscle proteostasis function can significantly ameliorate proteotoxicity and reduce neuroinflammation in the aging CNS. We derived cTFEB;HSA-Cre transgenic mice in the P301S MAPT background and we detected a significant reduction in hyperphosphorylated tau[AT8 phospho-tau antibody] in whole hippocampal lysates and in the dentate gyrus of cTFEB;HSACre;P301S mice compared to their single transgenic P301S littermate controls. Nanostring nCounter®AD panel analysis reveals displayed reductions in microglia activation modules in P301S MAPT/cTFEB:HSACre hippocampi, suggesting reduced neuroinflammation. We also determined that these CNS benefit sin P301S MAPT/cTFEB:HSACre mice were accompanied by activation of exercise-associated neurotrophic signaling and reduced markers of advancing tau-associated pathologies in the hippocampus. These provocative results suggest that enhanced skeletal muscle proteostasis modifies the accumulation of pathogenic tau isoforms and reduces neuroinflammation in the CNS of P301S MAPT mice via activation of exercise-associated signaling in the CNS.

DNASE1L3 regulation by transcription factor FOXP2 affects the proliferation, migration, invasion and tube formation of lung adenocarcinoma.

Lung adenocarcinoma (LUAD) is prone to bone metastasis, resulting in poor prognosis. The present study aimed to detect the expression of deoxyribonuclease 1-like 3 (DNASE1L3) and forkhead-box P2 (FOXP2) in LUAD cells to investigate the role of DNASE1L3 in the regulation of proliferation, migration, invasion and tube formation of LUAD cells and how FOXP2 affects DNASE1L3 expression. The expression of DNASE1L3 and FOXP2 in LUAD cells was analyzed by reverse transcription-quantitative PCR (RT-qPCR) and western blotting. The transfection efficiency of DNASE1L3 overexpression plasmids, FOXP2 overexpression or interference plasmids into A549 cells was also confirmed by RT-qPCR and western blotting. The viability, proliferation, migration and invasion and tube formation of LUAD cells following transfection was in turn detected by MTT, EdU staining, wound healing, Transwell and tube formation assay. The expression of proteins associated with epithelial-mesenchymal transformation and tube formation was detected by western blotting. Binding between DNASE1L3 and FOXP2 was confirmed by dual-luciferase reporter assay and chromatin immunoprecipitation. Gene Expression Profiling Interactive Analysis database predicted that underexpression of DNASE1L3 in LUAD was associated with poor prognosis. DNASE1L3 expression was decreased in LUAD cells and overexpression of DNASE1L3 inhibited the proliferation, migration, invasion and tube formation of LUAD cells. Transcription factor FOXP2 positively regulated DNASE1L3 transcription in LUAD cells. FOXP2 was also underexpressed in LUAD cells and downregulation of FOXP2 promoted proliferation, migration, invasion and tube formation of LUAD cells, which was reversed by overexpression of DNASE1L3. In conclusion, DNASE1L3 was positively regulated by transcription factor FOXP2 and overexpression inhibited proliferation, migration, invasion and tube formation of LUAD cells.

Direct Reprogramming Improves Cardiac Function and Reverses Fibrosis in Chronic Myocardial Infarction.

Because adult cardiomyocytes have little regenerative capacity, resident cardiac fibroblasts (CFs) synthesize extracellular matrix after myocardial infarction (MI) to form fibrosis, leading to cardiac dysfunction and heart failure. Therapies that can regenerate the myocardium and reverse fibrosis in chronic MI are lacking. The overexpression of cardiac transcription factors, including Mef2c/Gata4/Tbx5/Hand2 (MGTH), can directly reprogram CFs into induced cardiomyocytes (iCMs) and improve cardiac function under acute MI. However, the ability of in vivo cardiac reprogramming to repair chronic MI with established scars is undetermined. We generated a novel Tcf21iCre/reporter/MGTH2A transgenic mouse system in which tamoxifen treatment could induce both MGTH and reporter expression in the resident CFs for cardiac reprogramming and fibroblast lineage tracing. We first tested the efficacy of this transgenic system in vitro and in vivo for acute MI. Next, we analyzed in vivo cardiac reprogramming and fusion events under chronic MI using Tcf21iCre/Tomato/MGTH2A and Tcf21iCre/mTmG/MGTH2A mice, respectively. Microarray and single-cell RNA sequencing were performed to determine the mechanism of cardiac repair by in vivo reprogramming. We confirmed the efficacy of transgenic in vitro and in vivo cardiac reprogramming for acute MI. In chronic MI, in vivo cardiac reprogramming converted ≈2% of resident CFs into iCMs, in which a majority of iCMs were generated by means of bona fide cardiac reprogramming rather than by fusion with cardiomyocytes. Cardiac reprogramming significantly improved myocardial contraction and reduced fibrosis in chronic MI. Microarray analyses revealed that the overexpression of MGTH activated cardiac program and concomitantly suppressed fibroblast and inflammatory signatures in chronic MI. Single-cell RNA sequencing demonstrated that resident CFs consisted of 7 subclusters, in which the profibrotic CF population increased under chronic MI. Cardiac reprogramming suppressed fibroblastic gene expression in chronic MI by means of conversion of profibrotic CFs to a quiescent antifibrotic state. MGTH overexpression induced antifibrotic effects partly by suppression of Meox1, a central regulator of fibroblast activation. These results demonstrate that cardiac reprogramming could repair chronic MI by means of myocardial regeneration and reduction of fibrosis. These findings present opportunities for the development of new therapies for chronic MI and heart failure.

An Optogenetic-Controlled Cell Reprogramming System for Driving Cell Fate and Light-Responsive Chimeric Mice.

Pluripotent stem cells (PSCs) hold great promise for cell-based therapies, disease modeling, and drug discovery. Classic somatic cell reprogramming to generate induced pluripotent stem cells (iPSCs) is often achieved based on overexpression of transcription factors (TFs). However, this process is limited by side effect of overexpressed TFs and unpredicted targeting of TFs. Pinpoint control over endogenous TFs expression can provide the ability to reprogram cell fate and tissue function. Here, a light-inducible cell reprogramming (LIRE) system is developed based on a photoreceptor protein cryptochrome system and clustered regularly interspaced short palindromic repeats/nuclease-deficient CRISPR-associated protein 9for induced PSCs reprogramming. This system enables remote, non-invasive optogenetical regulation of endogenous Sox2and Oct4loci to reprogram mouse embryonic fibroblasts into iPSCs (iPSCLIRE ) under light-emitting diode-based illumination. iPSCLIRE cells can be efficiently differentiated into different cells by upregulating a corresponding TF. iPSCLIRE cells are used for blastocyst injection and optogenetic chimeric mice are successfully generated, which enables non-invasive control of user-defined endogenous genes in vivo, providing a valuable tool for facile and traceless controlled gene expression studies and genetic screens in mice. This LIRE system offers a remote, traceless, and non-invasive approach for cellular reprogramming and modeling of complex human diseases in basic biological research and regenerative medicine applications.

TWIST1 activates cancer stem cell marker genes to promote epithelial-mesenchymal transition and tumorigenesis in esophageal squamous cell carcinoma

BackgroundEsophageal squamous cell carcinoma (ESCC) is one of the deadliest cancers worldwide. Overexpression of EMT master transcription factors can promote differentiated cells to undergo cancer reprogramming processes and acquire a stem cell-like status.MethodsThe KYSE-30 and YM-1 ESCC cell lines were transduced with retroviruses expressing TWIST1 or GFP and analyzed by quantitative reverse transcription PCR (qRT-PCR), chromatin immunoprecipitation (ChIP), and immunostaining to investigate the correlation between TWIST1 and stemness markers expression. Cells expressing TWIST1 were characterized for mRNA candidates by qRT-PCR and for protein candidates by Flow cytometry and Immunocytochemistry. TWIST1-ESCC cells were also evaluated for apoptosis and drug resistance.ResultsHere we identify a role for TWIST1 in the establishment of ESCC cancer stem cell (CSC)-like phenotype, facilitating the transformation of non-CSCs to CSCs. We provide evidence that TWIST1 expression correlates with the expression of CSC markers in ESCC cell lines. ChIP assay results demonstrated that TWIST1 regulates CSC markers, including CD44, SALL4, NANOG, MEIS1, GDF3, and SOX2, through binding to the E-box sequences in their promoters. TWIST1 promoted EMT through E-cadherin downregulation and vimentin upregulation. Moreover, TWIST1 expression repressed apoptosis in ESCC cells through upregulation of Bcl-2 and downregulation of the Bax protein, and increased ABCG2 and ABCC4 transporters expression, which may lead to drug resistance.ConclusionsThese findings support a critical role for TWIST1 in CSC-like generation, EMT progression, and inhibition of apoptosis in ESCC. Thus, TWIST1 represents a therapeutic target for the suppression of esophageal cell transformation to CSCs and ESCC malignancy.

Overexpression of CiMYC2 Transcription Factor from Chrysanthemum indicum var. aromaticum Resulted in Modified Trichome Formation and Terpenoid Biosynthesis in Transgenic Tobacco

Overexpression of CiMYC2 Transcription Factor from Chrysanthemum indicum var. aromaticum Resulted in Modified Trichome Formation and Terpenoid Biosynthesis in Transgenic Tobacco

Exercise‐Associated Signaling Reduces Tau Accumulation and Neuroinflammation in P301S MAPT Transgenic Mice

AbstractBackgroundSkeletal muscle has recently arisen as a novel regulators of Central Nervous System (CNS) function and aging, secreting bioactive molecules known as myokines with proteostasis and metabolism‐modifying functions in targeted tissues, including the CNS. Myokine secretion is heavily modified by exercise, suggesting that myokine signaling in the periphery may underlie the well document geroprotective benefits of exercise on the brain. The following studies address muscle proteostasis, a pathway highly activated during exercise, as a potential new regulator of the neurocognitive benefits of exercise.MethodWe have recently generated a novel transgenic mouse with enhanced muscle proteostasis via moderate overexpression of Transcription Factor E‐B (TFEB), a powerful master regulator of cellular clearance and proteostasis. We have discovered that the resulting enhanced skeletal muscle proteostasis function can significantly ameliorate proteotoxicity and reduce neuroinflammation in the aging CNS. To directly test the potential neuroprotective effectsof enhancing skeletal muscle proteostasisin AD‐associated pathologies, we derived cTFEB;HSA‐Cre transgenic mice in the P301S MAPT background. This is a well‐characterized model of fronto‐temporal dementia and neurofibrillary tangle toxicity and has been previously shown to benefit from exercise interventions.ResultWe detected a significant reduction in the accumulation of hyperphosphorylated tau [AT8 phospho‐tau antibody] in whole hippocampal lysates and in the dentate gyrus of cTFEB;HSACre;P301S mice compared to their single transgenic P301S littermate controls. Nanostring nCounter®AD panel analysis reveals displayed reductions in microglia activation modules in P301S MAPT/cTFEB:HSACre hippocampi, suggesting reduced neuroinflammation. We also determined that these CNS benefits in P301S MAPT/cTFEB:HSACre mice were accompanied by activation of exercise‐associated neurotrophic signaling and reduced markers of advancing tau‐associated pathologies in the hippocampus.ConclusionThese provocative results suggest that enhanced skeletal muscle proteostasis modifies the accumulation of pathogenic tau isoforms and reduces neuroinflammation in the CNS of P301S MAPT mice via activation of exercise‐associated signaling in the CNS.