Expression Of Transcription Factors Research Articles

Circadian Rhythm Enhances mTORC1/AMPK Pathway-Mediated Milk Fat Synthesis in Dairy Cows via the Microbial Metabolite Acetic Acid.

Livestock may respond differently to circadian rhythms, leading to differences in the composition of the animal products. Nevertheless, the circadian effects on rumen microorganisms and animal products are poorly understood. In the study, it was found that dairy cows exhibited increased milk fat levels, decreased acetic acid concentrations in the rumen fluid, and elevated acetic acid levels in the blood during the night compared to those of the day. Correlational analyses suggested a high association between Succiniclasticum, Lactobacillus, Prevotellacene NK3B31_group, Muribaculaceae_unclassified, etc., which were significantly enriched in rumen fluid at night, and milk fat levels. The differential metabolite Vitamin B6, significantly elevated at night, promoted the translocation of acetic acid into the circulation by increasing the level of rumen epithelial MCT1 protein expression. In addition, we found that both acetic acid treatment time and dose modulated the expression of lipid metabolism transcription factors (PPARγ, PPARα, and SREBP1c) and downstream genes (FASN, SCD1, ACCα, and CPT1A). Additionally, the mTORC1 and AMPK pathways were responsible for the effects of acetic acid on transcription factors and genes involved in lipid metabolism. Differences in rumen microbial taxa were observed between the day and night. Microbial metabolite (acetic acid) was found to be absorbed into the bloodstream and entered the mammary gland at night at a significantly elevated level. This regulation impacted the expression of lipid metabolism-related transcription factors (PPARγ, PPARα, and SREBP1c), as well as downstream genes through the mTORC1 and AMPK signaling pathways, ultimately affecting milk fat synthesis. These findings provide a new perspective for the microbial regulation of milk synthesis.

Dysregulation of the p53 pathway provides a therapeutic target in aggressive pediatric sarcomas with stem-like traits.

Pediatric sarcomas are bone and soft tissue tumors that often exhibit high metastatic potential and refractory stem-like phenotypes, resulting in poor outcomes. Aggressive sarcomas frequently harbor a disrupted p53 pathway. However, whether pediatric sarcoma stemness is associated with abrogated p53 function and might be attenuated via p53 reactivation remains unclear. We utilized a unique panel of pediatric sarcoma models and tumor tissue cohorts to investigate the correlation between the expression of stemness-related transcription factors, p53 pathway dysregulations, tumorigenicity in vivo, and clinicopathological features. TP53 mutation status was assessed by next-generation sequencing. Major findings were validated via shRNA-mediated silencing and functional assays. The p53 pathway-targeting drugs were used to explore the effects and selectivity of p53 reactivation against sarcoma cells with stem-like traits. We found that highly tumorigenic stem-like sarcoma cells exhibit dysregulated p53, making them vulnerable to drugs that restore wild-type p53 activity. Immunohistochemistry of mouse xenografts and human tumor tissues revealed that p53 dysregulations, together with enhanced expression of the stemness-related transcription factors SOX2 or KLF4, are crucial features in pediatric osteosarcoma, rhabdomyosarcoma, and Ewing's sarcoma development. p53 dysregulation appears to be an important step for sarcoma cells to acquire a fully stem-like phenotype, and p53-positive pediatric sarcomas exhibit a high frequency of early metastasis. Importantly, reactivating p53 signaling via MDM2/MDMX inhibition selectively induces apoptosis in aggressive, stem-like Ewing's sarcoma cells while sparing healthy fibroblasts. Our results indicate that restoring canonical p53 activity provides a promising strategy for developing improved therapies for pediatric sarcomas with unfavorable stem-like traits.

BRAFV600E induces key features of LCH in iPSCs with cell type-specific phenotypes and drug responses.

Langerhans cell histiocytosis (LCH) is a clonal hematopoietic disorder defined by tumorous lesions containing CD1a+/CD207+ cells. Two severe complications of LCH are systemic hyperinflammation and progressive neurodegeneration. The scarcity of primary samples and lack of appropriate models limit our mechanistic understanding of LCH pathogenesis and affect patient care. We generated a human in vitro model for LCH using induced pluripotent stem cells (iPSCs) harboring the BRAFV600E mutation, the most common genetic driver of LCH. We show that BRAFV600E/WT iPSCs display myelo-monocytic skewing during hematopoiesis and spontaneously differentiate into CD1a+/CD207+ cells that are similar to lesional LCH cells and are derived from a CD14+ progenitor. We show that BRAFV600E modulates the expression of key transcription factors regulating monocytic differentiation and leads to an upregulation of pro-inflammatory molecules and LCH marker genes early during myeloid differentiation. In vitro drug testing revealed that BRAFV600E-induced transcriptomic changes are reverted upon treatment with MAPK-pathway inhibitors (MAPKi). Importantly, MAPKi do not affect myeloid progenitors but reduces only the mature CD14+ cell population. Furthermore, iPSC-derived neurons (iNeurons) co-cultured with BRAFV600E/WT iPSC-derived microglia-like cells (iMGL), differentiated from iPSC-derived CD34+ progenitors, exhibit signs of neurodegeneration with neuronal damage and release of neurofilament light chain. In summary, the iPSC-based model described here provides a platform to investigate the effects of BRAFV600E in different hematopoietic cell types and provides a tool to compare and identify novel approaches for the treatment of BRAFV600E-driven diseases.

The mechanism of DEHP-induced lipid accumulation in liver of female zebrafish

Diethylhexyl phthalate (DEHP) is a typical environmental pollutant and poses a potential threat to organisms by disrupting the lipid metabolism. This study found that DEHP at environmental concentrations, led to lipid accumulation in female zebrafish, as indicated by significant increases in the content of total cholesterol, triglycerides and the lipid droplets, in a concentration-dependent manner. However, how DEHP induces the lipid accumulation remains poorly understood. Our results demonstrated that DEHP up-regulated the expression of fat synthesis related-genes fas, acc, acs, elvol6, scd and dgat1, and increased the enzymatic activity of fatty acid synthase and acetyl-CoA carboxylase. Furthermore, the expression of several key transcription factors that regulate fat synthesis was detected, among which active sterol regulatory element-binding protein-1 (SREBP-1) was significantly increased. When active SREBP-1 was inhibited with specific inhibitor or knocked down by transient transfection, the expression of lipid synthesis-related genes was significantly decreased in DEHP group, indicating that DEHP disrupted the lipid synthesis via SREBP-1 pathway. Additionally, molecular docking revealed direct interaction sites between DEHP and SREBP-1. Our findings revealed that DEHP could directly activate SREBP-1-mediated lipid synthesis, providing theoretical basis for DEHP threatening biological health.

Assessment of the relative cardiotoxicity and behavioral effects of butylated hydroxytoluene and its metabolites in developing zebrafish (Danio rerio)

Butylated hydroxytoluene (BHT) and its transformation products are ubiquitously detected in aquatic environments. Despite studies reporting on the adverse effects of BHT exposure in early-staged zebrafish, the comparative toxicity of its metabolites is not known. To address this, zebrafish embryos were exposed continuously to 0.01–1 μM BHTs (BHT, BHT-Q, BHT-OH, BHT-CHO, and BHT-COOH) for up to 6 days. Each chemical altered the heart rates of developing zebrafish at 72 hpf. When assessing cardiac morphology at 48 and 72 hpf, BHT-COOH showed stronger effects compared to BHT in inducing pericardial edema and myocardial hypertrophy. This effect is hypothesized to be attributed to differences in transcriptional regulation of key genes during cardiac development. BHT predominantly affected transcript expression in the early (15 hpf) or late stages (48–72 hpf) of heart development, but did not impact the transcription during the middle stage (24–36 hpf). Conversely, BHT-COOH altered the expression of early transcription factors (i.e. tbx5, nkx2.5, gata4, hand2) and functional genes (i.e. myh6, nppa, cacna1ab, and atp2a2) at all stages of cardiac development. The effects on the heart may also be related to behavioral changes observed in larval fish. Behavior was most sensitive with low chemical exposures (0.01 μM), while at higher concentrations, heart rate was a more sensitive indicator of BHT-induced toxicity. Taken together, our results indicate that BHTs induce adverse effects on cardiovascular function and BHT metabolites may pose higher risk than the parent compound.

Control of cell fate upon transcription factor-driven cardiac reprogramming.

Adult mammals are susceptible to substantial cardiomyocyte (CM) loss following various cardiac diseases due to the limited capacity of CM proliferation and regeneration. Recently, direct cardiac reprogramming, converting fibroblasts into induced CMs, has been achieved both in vitro and in vivo through forced expression of transcription factors (TFs). This review encapsulates the advancements made in enhancing reprogramming efficiency and underlying molecular mechanisms. It covers the optimization of TF-based reprogramming cocktails and in vivo delivery platform and recently identified regulators in enhancing reprogramming efficiency. In addition, we discuss recent insights into the molecular mechanisms of direct cardiac reprogramming from single-cell omics analyses. Finally, we briefly touch on remaining challenges and prospective direction of this field.

Expression of PPAR-γ TF by newly synthesized thiazolidine-2,4-diones to manage glycemic control: Insights from in silico, in vitro and experimental pharmacology in wistar rats.

In pursuit of novel antidiabetic agents to combat type II diabetes mellitus, our study focused on identifying pharmacophoric features responsible for PPAR-γ expression, a key regulator of glucose homeostasis and lipid metabolism. This goal was achieved through pharmacophore model generation and screening of rationally designed library of thiazolidine-2,4-dione hybrids (7a-7f). The top hits were synthesized, characterized, and evaluated for their in vitro and in vivo antidiabetic activities. Among these, compounds 7b and 7c emerged as promising candidates, exhibiting significant in vitro inhibitory activity against human pancreatic α-amylase (HPA) and human liver α-glucosidase (HLAG) enzymes, along with enhanced glucose uptake in L6 myotube cell lines. Specifically, compound 7b showed 29.04±1.13µM HPA inhibition, 34.21±1.16µg/mL HLAG inhibition, and 77.12±1.02% glucose uptake, while compound 7c displayed 28.35±1.01µM HPA inhibition, 26.21±1.17µM HLAG inhibition, and 78.54±0.54% glucose uptake. Mechanistic studies revealed a dose-dependent increase in PPAR-γ transcription factor expression, supported by molecular docking that showed favorable interactions with key residues TYR473, SER289, and HIE323. Molecular dynamics simulations confirmed the stability of these interactions, and MM/GBSA binding free energy calculations indicated potential for further optimization. In vivo studies in STZ-induced diabetic Wistar rats demonstrated significant improvements in glucose homeostasis, insulin sensitivity, and lipid metabolism, with a notable decrease in triglycerides and VLDL levels. Compound 7c also showed an improved pharmacokinetic profile with a half-life of 4.01h and an elimination rate constant of 0.325, compared to compound 7b. Both compounds enhanced glycogen content and antioxidant biomarkers, with a high safety profile (LD50 of 500mg/kg). Overall, compound 7c stands out as a promising lead for further development, with compound 7b also showing strong potential, providing valuable insights for future antidiabetic drug development efforts.

In human CD4+ T-Cells, omeprazole suppresses proliferation, downregulates V-ATPase, and promotes differentiation toward an autoimmunity-favoring phenotype

BackgroundProton pump inhibitors (PPIs) represent a commonly prescribed class of medications. Triggered by findings indicating a correlation between PPI usage and susceptibility to infectious or autoimmune diseases, we studied the impact of a pharmacological concentration of omeprazole on human CD4+ T-cells. MethodsIn mixed lymphocyte reactions (MLRs), we analyzed the proliferation index and measured the concentration of key cytokines representative of distinct CD4+ T-cell subsets. In CD4+ T-cells isolated from the MLRs, we evaluated proliferation markers and pathways, the expression of signature transcription factors of CD4+ T-cell subsets, vacuolar H+- ATPase (V-ATPase) levels, and the activation status of AMP-activated kinase (AMPK) and mammalian target of rapamycin complex-1 (mTORC1). ResultsOmeprazole reduced proliferation index in MLRs, and in isolated CD4+ T-cells, it downregulated the proliferation marker Ki-67, possibly mediated by the p53- p21 pathway. Analysis of cytokines and signature transcription factors of CD4+ T-cell subsets indicated that omeprazole decreased T helper 1 (Th1) differentiation, had negligible impact on Th2 differentiation, increased Th17 differentiation, and reduced regulatory T-cell (Treg) differentiation. Omeprazole also decreased V-ATPase, a known target of PPIs and a site for AMPK and mTORC1 activation. Consequently, this led to diminished activation of these kinases, potentially elucidating the mechanism by which omeprazole influences CD4+ T-cell differentiation. ConclusionOmeprazole downregulates V-ATPase and inhibits activation of AMPK and mTORC1. As a result, omeprazole suppresses CD4+ T-cell clonal expansion, potentially contributing to the observed association between PPIs and susceptibility to infections. Additionally, it modulates CD4+ T-cell differentiation in a manner that favors autoimmunity.

Analysis of Transcriptional and Metabolic Differences in the Petal Color Change Response to High-Temperature Stress in Various Chrysanthemum Genotypes

Flower color is one of the most important ornamental traits of chrysanthemums. Previous studies have shown that high temperatures can cause the petals of some chrysanthemum varieties to fade; however, the molecular mechanisms behind this phenomenon remain poorly understood. This study examines the mechanisms of color change in purple chrysanthemums under high-temperature stress using combined metabolomic and transcriptomic analyses. Four chrysanthemum varieties—two heat-stable (‘Zi Feng Che’ and ‘Chrystal Regal’) and two heat-sensitive (‘Zi Hong Tuo Gui’ and ‘Zi Lian’)—were analyzed. High-temperature conditions (35 °C) significantly downregulated key anthocyanins in heat-sensitive varieties, particularly cyanidin-3-O-(3″,6″-O-dimalonyl)glucoside and pelargonidin-3-O-(3″,6″-O-dimalonyl)glucoside. Transcriptome analysis revealed differential gene expression involved in anthocyanin biosynthesis and degradation, with significant enrichment in the MAPK signaling, phenylpropanoid biosynthesis, flavonoid biosynthesis, and anthocyanin biosynthesis pathways. The study highlighted the differential expression of CHS, DFR, ANS, GT1, 3AT, and UGT75C1 genes in anthocyanin synthesis between heat-sensitive and heat-tolerant varieties. Compared to heat-stable varieties, the petals of heat-sensitive varieties exhibited greater differential expression of heat-responsive transcription factors, including HSFs, ERFs, MYBs, and WRKYs. Genes that show a significant negative correlation with the downregulated anthocyanins, including Cse_sc012959.1_g030.1 (βG), Cse_sc001798.1_g020.1 (MYB), Cse_sc006944.1_g010.1 (MYB), and Cse_sc000572.1_g090.1 (HSF), might regulate anthocyanin accumulation in chrysanthemums in response to high-temperature stress. These results provide guidance for the cultivation management and variety selection of chrysanthemums under high-temperature conditions. Additionally, they lay the foundation for elucidating the molecular mechanisms of flower color stability under heat stress and for breeding new heat-tolerant varieties.

Exploring the Anti-melanogenic, Antioxidant, and Anti-inflammatory Activities of A Composition: Glabridin, Resveratrol and Ellagic Acid

Background: Plant extracts have wide applications in food, nutrition, and cosmetics, which results in a deeper investigation of natural ingredients. Numerous natural ingredients have been demonstrated to exhibit multiple activities, including antioxidation, anti-inflammation, and anti-melanogenesis. However, their combinations have not been well investigated, which could provide stronger performance with less toxicity and easier applications. Methods: We used B16F10 cells treated with alpha-melanocyte stimulating hormone (αMSH) for melanogenesis-related studies, including cellular melanin content, tyrosinase activity, and gene or protein expression. MTT assay was used to evaluate cell viability. DPPH scavenging activity was measured for antioxidation. Nitric oxide (NO) content was evaluated in lipopolysaccharide (LPS) treated RAW264.7 cells to indicate the performance on anti-inflammation. Results: In this study, six different compounds and their combinations were tested for melanogenesis. The results showed that the combination of glabridin, resveratrol, and ellagic acid (GRE) exhibited the highest efficiency, which was mainly manifested as inhibition of melanin production and tyrosinase activity, higher DPPH scavenging rate, and inhibition of nitric oxide (NO) production. Meanwhile, our results showed that GRE could significantly downregulate the expression of microphthalmia-associated transcription factor (MITF) related genes and proteins and could also inhibit the phosphorylation of cyclic AMP response element-binding protein (CREB), which was the upstream signal of MITF. Conclusion: The results suggest GRE exhibits high efficiency in inhibiting anti-melanogenesis, antioxidation, and anti-inflammation. Furthermore, GRE could downregulate the phosphorylation of the CREB and MITF signal pathway, which provides a theoretical basis for its application in pigmentation disorder disease and cosmetics.

Potassium Release From the Habenular Astrocytes Induces Depressive-Like Behaviors in Mice.

The habenula has been implicated in psychiatric disorders such as depression, primarily because of its role in the modulation of the dopaminergic and serotonergic systems, which play a role in the pathophysiology of these disorders. Despite growing evidence supporting the role of the habenula in behavioral regulation, the process by which neural cells develop in the habenula remains elusive. Since the habenular anlage is found in the prosomere 2 domain expressing transcription factor Dbx1 in mouse embryos, we hypothesized that the Dbx1-expressing prosomere domain is a source of astrocytes that modulate neuronal activity in the habenula. To address this, we examined the cell lineage generated from Dbx1-expressing cells in male mice using tamoxifen-inducible Cre recombinase under the control of the Dbx1 promoter. Perinatal induction of Cre activity labeled cells migrating radially from the ventricular zone to the pial side of the habenular anlage, and eventually showed astrocyte-like morphology with expression of the marker protein, S100β, for mature astrocytes in the habenula of the adult mouse. Photostimulation of astrocytes expressing ChR2 released potassium ions into the extracellular space, which in turn excited the neurons with an increased firing rate in the lateral habenula. Finally, photostimulation of habenular astrocytes exacerbated depression-like phenotypes with reduced locomotor activity, exaggerated despair behavior and impaired sucrose preference in open-field, tail suspension and sucrose preference tests, respectively. These results indicated that the Dbx1-expressing perinatal domain generated astrocytes that modulated neuronal activity via the regulation of extracellular potassium levels.

Novel Immunohistochemical Profiling of Small-Cell Lung Cancer: Correlations Between Tumor Subtypes and Immune Microenvironment

Background/Objectives: Small-cell lung cancer (SCLC) is a highly aggressive malignancy with an emerging molecular classification based on the expression of the transcription factors ASCL1, NEUROD1, and POU2F3. This study aimed to explore the relationship between these novel subtypes and the tumor immune microenvironment (TIME), particularly CD8+ and CD4+ tumor-infiltrating lymphocytes (TILs). Methods: In 51 cases of patients with SCLC, immunohistochemical (IHC) stains for ASCL1, NEUROD1, POU2F3, CD56, Ki67, CD8, and CD4 were performed. H-scores for the novel transcription factors were calculated to determine tumor subtype. CD8+ and CD4+ TIL counts were averaged across 10 high-power fields. The Kruskal–Wallis test and subsequent post hoc Dunn tests were used to determine the differences in transcription factor expression and TILs across subtypes. Results: In our cohort, 68.62% of our cases were SCLC-A, 9.80% were SCLC-N, 7.84% were SCLC-P, and 13.72% were SCLC-I. Significant differences were observed in the expression of ASCL1, NEUROD1, and POU2F3 across subtypes. CD8+ TILs were more abundant in SCLC-P and SCLC-I. CD8+ TILs were negatively correlated with ASCL1 expression (p < 0.05) and positively correlated with POU2F3 expression (p < 0.005). Conclusions: This study highlights the need to integrate the novel SCLC classification with data regarding the TIME to better inform patient prognosis and treatment.

Defense-related enzymes associated with resistance to onion Fusarium basal rot

This study was carried out to quantify changes in the activities of antioxidative enzymes such as catalase (CAT), peroxidase (POX) and superoxide dismutase (SOD) in two resistant onion cultivars 'Saba - HS' and 'Saba' and two susceptible cultivars 'Golden Eye' and 'Savannah Sweet' following an inoculation with Fusarium oxysporum f. sp. cepae (FOC) at seedling stage. Further, we assessed the expression of transcription factors (TFs), R1, PR5 and RGA29-genes that are involved in conferring resistance post-inoculation using qRT-PCR. The results revealed that the least disease severity occurred with the resistant 'Saba - HS' (4.7%) and 'Saba' (6.7%) cultivars, whereas the highest disease severity occurred with the susceptible 'Golden Eye' (89.6%) and 'Savannah Sweet' (88.9%) cultivars, respectively. Both resistant genotypes 'Saba' and 'Saba-HS' showed a significant increase in CAT, POX, and SOD activities at a transcriptional level. CAT activity was upregulated 4.81-fold in 'Saba' and 4.22-fold in 'Saba-HS' followed by POX where 'Saba' showed an increase by 3.53-fold and 'Saba-HS' by 2.35-fold, and SOD 'Saba' 17.46-fold and 'Saba-HS' 22.95-fold, relatively. Marker genes, RGA29, R1 and PR5, were also upregulated in the resistant-genotypes by 3.83, 4.78 and 5.01-fold, in comparison to their-controls, respectively. Similar trends were recorded for the biomass growth parameters (BGPs).

The Chicken HDAC4 Promoter and Its Regulation by MYC and HIF1A

Background: Histone deacetylase 4 (HDAC4) is a member of the class II histone deacetylase family, whose members play a crucial role in various biological processes. An in-depth investigation of the transcriptional characteristics of chicken HDAC4 can provide fundamental insights into its function. Methods: We examined HDAC4 expression in chicken embryonic stem cells (ESC) and spermatogonial stem cells (SSC) and cloned a 444 bp fragment from upstream of the chicken HDAC4 transcription start site. Subsequently, we constructed pEGFP-HDAC4 and a series of 5′-deletion luciferase reporter constructs, which we transfected into DF-1 cells to measure their transcriptional activity. The regulatory mechanisms of chicken HDAC4 expression were investigated by performing trichostatin A (TSA) treatment, deleting putative transcription factor binding sites, and altering transcription factor expression levels. Results: HDAC4 exhibited higher expression in SSC than in ESC. We confirmed that the upstream region from −295 bp to 0 bp is the core transcriptional region of HDAC4. TSA effectively inhibited HDAC4 transcription, and bioinformatics analysis indicated that the chicken core HDAC4 promoter sequence exhibits high homology with those of other avian species. The myelocytomatosis viral oncogene homolog (MYC) and hypoxia-inducible factor 1 α (HIF1A) transcription factors were predicted to bind to this core region. Treatment with TSA for 24 h resulted in the upregulation of MYC and HIF1A, which repressed HDAC4 transcription. Conclusions: Our results provide a basis for subsequent investigations into the regulation of HDAC4 expression and biological function.

Metabolite differences and molecular mechanism between dehiscent and indehiscent capsule of mature sesame

The loss of sesame capsule seed prior to harvest poses a significant economical challenge in mechanized production. The metabolites involved in capsule closure are still unclear. Using comparative metabolome and transcriptome analysis, this work investigated the molecular regulation and enrichment pathways in two sesame types of indehiscent capsule WanZhi28 (ND) and dehiscent capsule WanZhi2 (WZ2). The findings demonstrated that genes and metabolites were significantly enriched in lignin synthesis-related pathways. Furthermore, data suggests that lipid and sugar metabolism may have an impact on capsule closure. Apart from its function in cell signaling, the latter may contribute to the glycosylation of lignin monomers, while the former may provide ATP for cellular microtubule movement. This work concurrently focused on a large number of differentially expressed transcription factors linked to the sesame capsule's anti-cleft mechanism, providing new evidence for the discovery and use of functional markers and genes for capsule dehiscence. The identification of key pathways and regulatory mechanisms offers valuable information for developing strategies to mitigate seed loss during harvest, ultimately contributing to more efficient and profitable sesame production.

Genetic Evidence for Estrogenic Effects of Benzophenone-2 on Zebrafish Neurodevelopment and Its Signaling Mechanism.

Estrogens play a crucial role in regulating various biological responses during the early stages of neurodevelopment. Benzophenone-2 (BP2), a widely used organic ultraviolet (UV) filter, has been proven as an estrogenic compound, whereas the estrogenic effects of BP2 on neurodevelopment remain largely unknown. Here, we investigated the neurodevelopmental toxicity of BP2 by exposing zebrafish embryos from 2 to 120 h postfertilization (hpf) at environmentally relevant concentrations. We demonstrated that early life exposure to BP2 induced multiple concentration-dependent impairments in the nervous system, including hypoactivity, abnormal brain morphology, impaired neurocyte proliferation, shortened axon, and increased neurocyte apoptosis. Moreover, metabolomic profiling revealed a decrease in dopamine (DA) and its metabolites in BP2-treated larvae. Using E2 treatment and morpholino knockdown assays, we provided strong genetic evidence that the BP2-induced behavioral disorders were associated with estrogen-dependent signaling, especially estrogen receptors 2a and 2b (esr2). Subsequently, transcriptomic profiling indicated that the activation of esr2 further inhibited the expression of LIM homeobox transcription factor 1 β a (lmx1ba), which is vital for normal neurodevelopment. Consistently, the overexpression of lmx1ba and inhibition of esr2 obviously alleviated BP2-caused neurotoxicity, uncovering a seminal role of esr2 and lmx1ba in BP2-induced neurodevelopmental toxicity. Our findings provide the first evidence in fish that BP2 can induce neurodevelopmental deficits and brain dysfunction and offer novel insights into the mechanisms of toxicity of BP2 as well as other emerging benzophenones.

Exposure to Radiofrequency Electromagnetic Fields Enhances Melanin Synthesis by Activating the P53 Signaling Pathway in Mel-Ab Melanocytes.

The skin is the largest body organ that can be physiologically affected by exposure to radiofrequency electromagnetic fields (RF-EMFs). We investigated the effect of RF-EMFs on melanogenesis; Mel-Ab melanocytes were exposed to 1760 MHz radiation with a specific absorption rate of 4.0 W/kg for 4 h/day over 4 days. Exposure to the RF-EMF led to skin pigmentation, with a significant increase in melanin production in Mel-Ab melanocytes. The phosphorylation level of cAMP response element binding protein (CREB) and the expression of microphthalmia-associated transcription factor (MITF), which regulate the expression of tyrosinase, were significantly increased in Mel-Ab after RF-EMF exposure. Interestingly, the expression of tyrosinase was significantly increased, but tyrosinase activity was unchanged in the RF-EMF-exposed Mel-Ab cells. Additionally, the expression of p53 and melanocortin 1 receptor (MC1R), which regulate MITF expression, was significantly increased. These results suggest that the RF-EMF induces melanogenesis by increasing phospho-CREB and MITF activity. Importantly, when Mel-Ab cells were incubated at 38 °C, the melanin production and the levels of tyrosinase significantly decreased, indicating that the increase in melanin synthesis by RF-EMF exposure is not due to a thermal effect. In conclusion, RF-EMF exposure induces melanogenesis in Mel-Ab cells through the increased expression of tyrosinase via the activation of MITF or the phosphorylation of CREB, which are initiated by the activation of p53 and MC1R.

Transcription regulation of African swine fever virus: dual role of M1249L

African swine fever virus (ASFV), which poses significant risks to the global economy, encodes a unique host-independent transcription system. This system comprises an eight-subunit RNA polymerase (vRNAP), temporally expressed transcription factors and transcript associated proteins, facilitating cross-species transmission via intermediate host. The protein composition of the virion and the presence of transcription factors in virus genome suggest existence of distinct transcription systems during viral infection. However, the precise mechanisms of transcription regulation remain elusive. Through analyses of dynamic transcriptome, vRNAP-associated components and cell-based assay, the critical role of M1249L in viral transcription regulation has been highlighted. Atomic-resolution structures of vRNAP-M1249L supercomplex, exhibiting a variety of conformations, have uncovered the dual functions of M1249L. During early transcription, M1249L could serve as multiple temporary transcription factors with C-terminal domain acting as a switcher for activation/inactivation, while during late transcription it aids in the packaging of the transcription machinery. The structural and functional characteristics of M1249L underscore its vital roles in ASFV transcription, packaging, and capsid assembly, presenting novel opportunities for therapeutic intervention.

The molecular subtypes of small cell lung cancer defined by key transcription factors and their clinical significance

BackgroundLung cancer, a prevalent and deadly malignancy, is classified into small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). SCLC is further subdivided into four molecular subtypes—SCLC-A, SCLC-N, SCLC-P, and SCLC-I—based on key transcription factor expression. MethodsImmunohistochemistry (IHC) was used to assess ASCL1, NEUROD1, and POU2F3 expression in tumor tissues. The H-Score quantified these results. Clinical characteristics, overall survival (OS), progression-free survival (PFS), and treatment responses were analyzed by subtype, and sensitivity to different treatments was assessed. Risk factors were identified through univariate and multivariate analyses. ResultsIHC and H-Score analysis showed that POU2F3 expression was mutually exclusive with ASCL1 or NEUROD1. Subtype distribution was as follows: SCLC-A (40 %), SCLC-N (33 %), SCLC-P (7 %), and SCLC-I (20 %). There were no significant differences in baseline characteristics, OS (p = 0.829), or PFS (p = 0.924) among subtypes. However, the SCLC-I subtype showed a trend toward improved outcomes with platinum-based doublet chemotherapy plus immune checkpoint inhibitors. Multivariate COX regression identified M stage (HR: 1.72, 95 % CI: 1.13–2.63, p = 0.012) and bone metastasis at diagnosis (HR: 1.58, 95 % CI: 1.02–2.43, p = 0.040) as independent risk factors. ConclusionThis study confirmed the SCLC subtyping based on key transcription factors. While no significant differences in OS and PFS among subtypes were found, the SCLC-I subtype showed potential benefit from platinum-based chemotherapy combined with immune checkpoint inhibitors. M stage and bone metastasis at diagnosis were identified as independent risk factors for SCLC.

A Snapshot of Early Transcriptional Changes Accompanying the Pro-Neural Phenotype Switch by NGN2, ASCL1, SOX2, and MSI1 in Human Fibroblasts: An RNA-Seq Study.

Direct pro-neural reprogramming is a conversion of differentiated somatic cells to neural cells without an intermediate pluripotency stage. It is usually achieved via ectopic expression (EE) of certain transcription factors (TFs) or other reprogramming factors (RFs). Determining the transcriptional changes (TCs) caused by particular RFs in a given cell line enables an informed approach to reprogramming initiation. Here, we characterized TCs in the human fibroblast cell line LF1 on the 5th day after EE of the single well-known pro-neural RFs NGN2, ASCL1, SOX2, and MSI1. As assessed by expression analysis of the bona fide neuronal markers nestin and beta-III tubulin, all four RFs initiated pro-neuronal phenotype conversion; analysis by RNA-seq revealed striking differences in the resulting TCs, although some pathways were overlapping. ASCL1 and SOX2 were not sufficient to induce significant pro-neural phenotype switches using our EE system. NGN2 induced TCs indicative of cell phenotype changes towards neural crest cells, neural stem cells, mature neurons, as well as radial glia, astrocytes, and oligodendrocyte precursors and their mature forms. MSI1 mainly induced a switch towards early stem-like cells, such as radial glia.