ABSTRACT
Self-renewal and pluripotency of the embryonic stem cell (ESC) state are established and maintained by multiple regulatory networks that comprise transcription factors and epigenetic regulators. While much has been learned regarding transcription factors, the function of epigenetic regulators in these networks is less well defined. We conducted a CRISPR-Cas9-mediated loss-of-function genetic screen that identified two epigenetic regulators, TAF5L and TAF6L, components or co-activators of the GNAT-HAT complexes for the mouse ESC (mESC) state. Detailed molecular studies demonstrate that TAF5L/TAF6L transcriptionally activate c-Myc and Oct4 and their corresponding MYC and CORE regulatory networks. Besides, TAF5L/TAF6L predominantly regulate their target genes through H3K9ac deposition and c-MYC recruitment that eventually activate the MYC regulatory network for self-renewal of mESCs. Thus, our findings uncover a role of TAF5L/TAF6L in directing the MYC regulatory network that orchestrates gene expression programs to control self-renewal for the maintenance of mESC state.
Subject(s)
Embryonic Stem Cells/metabolism , Gene Regulatory Networks , Induced Pluripotent Stem Cells/metabolism , Proto-Oncogene Proteins c-myc/genetics , TATA-Binding Protein Associated Factors/genetics , Animals , CRISPR-Cas Systems , Cell Cycle/genetics , Cell Proliferation , Cellular Reprogramming , Embryo, Mammalian , Embryonic Stem Cells/cytology , Epigenesis, Genetic , Fibroblasts/cytology , Fibroblasts/metabolism , Gene Editing , Gene Expression Regulation , HEK293 Cells , Histones/genetics , Histones/metabolism , Humans , Induced Pluripotent Stem Cells/cytology , Mice , Primary Cell Culture , Protein Isoforms/genetics , Protein Isoforms/metabolism , Proto-Oncogene Proteins c-myc/metabolism , Signal Transduction , TATA-Binding Protein Associated Factors/metabolismABSTRACT
The reprogramming of human somatic cells to primed or naive induced pluripotent stem cells recapitulates the stages of early embryonic development1-6. The molecular mechanism that underpins these reprogramming processes remains largely unexplored, which impedes our understanding and limits rational improvements to reprogramming protocols. Here, to address these issues, we reconstruct molecular reprogramming trajectories of human dermal fibroblasts using single-cell transcriptomics. This revealed that reprogramming into primed and naive pluripotency follows diverging and distinct trajectories. Moreover, genome-wide analyses of accessible chromatin showed key changes in the regulatory elements of core pluripotency genes, and orchestrated global changes in chromatin accessibility over time. Integrated analysis of these datasets revealed a role for transcription factors associated with the trophectoderm lineage, and the existence of a subpopulation of cells that enter a trophectoderm-like state during reprogramming. Furthermore, this trophectoderm-like state could be captured, which enabled the derivation of induced trophoblast stem cells. Induced trophoblast stem cells are molecularly and functionally similar to trophoblast stem cells derived from human blastocysts or first-trimester placentas7. Our results provide a high-resolution roadmap for the transcription-factor-mediated reprogramming of human somatic cells, indicate a role for the trophectoderm-lineage-specific regulatory program during this process, and facilitate the direct reprogramming of somatic cells into induced trophoblast stem cells.
Subject(s)
Cellular Reprogramming/genetics , Gene Expression Regulation , Induced Pluripotent Stem Cells/cytology , Induced Pluripotent Stem Cells/metabolism , Trophoblasts/cytology , Trophoblasts/metabolism , Adult , Chromatin/genetics , Chromatin/metabolism , Ectoderm/cytology , Ectoderm/metabolism , Female , Fibroblasts/cytology , Fibroblasts/metabolism , Humans , Transcription, GeneticABSTRACT
Histone H3.3 is an H3 variant which differs from the canonical H3.1/2 at four residues, including a serine residue at position 31 which is evolutionarily conserved. The H3.3 S31 residue is phosphorylated (H3.3 S31Ph) at heterochromatin regions including telomeres and pericentric repeats. However, the role of H3.3 S31Ph in these regions remains unknown. In this study, we find that H3.3 S31Ph regulates heterochromatin accessibility at telomeres during replication through regulation of H3K9/K36 histone demethylase KDM4B. In mouse embryonic stem (ES) cells, substitution of S31 with an alanine residue (H3.3 A31 -phosphorylation null mutant) results in increased KDM4B activity that removes H3K9me3 from telomeres. In contrast, substitution with a glutamic acid (H3.3 E31, mimics S31 phosphorylation) inhibits KDM4B, leading to increased H3K9me3 and DNA damage at telomeres. H3.3 E31 expression also increases damage at other heterochromatin regions including the pericentric heterochromatin and Y chromosome-specific satellite DNA repeats. We propose that H3.3 S31Ph regulation of KDM4B is required to control heterochromatin accessibility of repetitive DNA and preserve chromatin integrity.
Subject(s)
Heterochromatin , Histones , Animals , Mice , Histones/genetics , Histones/metabolism , Heterochromatin/genetics , Histone Demethylases/metabolism , Phosphorylation , Chromatin Assembly and DisassemblyABSTRACT
Regulatory elements (REs) consist of enhancers and promoters that occupy a significant portion of the noncoding genome and control gene expression programs either in cis or in trans Putative REs have been identified largely based on their regulatory features (co-occupancy of ESC-specific transcription factors, enhancer histone marks, and DNase hypersensitivity) in mouse embryonic stem cells (mESCs). However, less has been established regarding their regulatory functions in their native context. We deployed cis- and trans-regulatory elements scanning through saturating mutagenesis and sequencing (ctSCAN-SMS) to target elements within the â¼12-kb cis-region (cis-REs; CREs) of the Oct4 gene locus, as well as genome-wide 2,613 high-confidence trans-REs (TREs), in mESCs. ctSCAN-SMS identified 10 CREs and 12 TREs as novel candidate REs of the Oct4 gene in mESCs. Furthermore, deletions of these candidate REs confirmed that the majority of the REs are functionally active, and CREs are more active than TREs in controlling Oct4 gene expression. A subset of active CREs and TREs physically interact with the Oct4 promoter to varying degrees; specifically, a greater number of active CREs, compared with active TREs, physically interact with the Oct4 promoter. Moreover, comparative genomics analysis reveals that a greater number of active CREs than active TREs are evolutionarily conserved between mice and primates, including humans. Taken together, our study demonstrates the reliability and robustness of ctSCAN-SMS screening to identify critical REs and investigate their roles in the regulation of transcriptional output of a target gene (in this case Oct4) in their native context.
Subject(s)
Genetic Loci , Mouse Embryonic Stem Cells/metabolism , Octamer Transcription Factor-3/metabolism , Regulatory Elements, Transcriptional , Animals , CRISPR-Cas Systems , Cell Line , Genome-Wide Association Study , Humans , Mice , Mouse Embryonic Stem Cells/cytology , Octamer Transcription Factor-3/geneticsABSTRACT
Contaminations of heavy metals such as lead (Pb) and cadmium (Cd) in medicinal plants (MPs) not only restrict their safe consumption due to health hazards but also lower their productivity. Biochar amendments in the soil are supposed to immobilize the toxic metals, improve the soil quality and agricultural productivity. However, the impact of biochar on growth attributes, metal accumulation, pharmacologically active compounds of MPs, and health risk is less explored. An experiment was performed on three medicinal plants (Bacopa monnieri (L.), Andrographis paniculata (Burmf.) Nees, and Withaniasomnifera (L.)) grown in a greenhouse in soil co-contaminated with Pb and Cd (at two concentrations) without and with biochar amendments (2 and 4% application rates). The fractionation of Pb and Cd, plant growth parameters, stress enzymes, photosynthetic capacity, pharmacologically active compounds, nutrient content, uptake and translocation of metals, antioxidant activities, and metabolite content were examined in the three MPs. The accumulation of Pb and Cd varied from 3.25-228 mg kg1 and 1.29-20.2 mg kg-1 , respectively, in the three MPs, while it was reduced to 0.08-18 mg kg-1 and 0.03-6.05 mg kg-1 upon biochar treatments. Plants grown in Pb and Cd co-contaminated soil had reduced plant biomass (5-50% depending on the species) compared to control and a deleterious effect on photosynthetic attributes and protein content. However, biochar amendments significantly improved plant biomass (21-175%), as well as photosynthesis attributes, chlorophyll, and protein contents. Biochar amendments in Pb and Cd co-contaminated soil significantly reduced the health hazard quotient (HQ) estimated for the consumption of these medicinal herbs grown on metal-rich soil. An enhancement in secondary metabolite content and antioxidant properties was also observed upon biochar treatments. These multiple beneficial effects of biochar supplementation in Pb and Cd co-contaminated soil suggested that a biochar amendment is a sustainable approach for the safe cultivation of MPs. This article is protected by copyright. All rights reserved.
ABSTRACT
Parkinson's disease (PD) pathogenesis inevitably involves neuroinflammatory responses attained through contribution of both neuron and glial cells. Investigation done in both experimental models of PD and in samples of PD patients suggested the involvement of both central and peripheral inflammatory responses during PD pathogenesis. Such neuroinflammatory responses could be regulated by neuron-glia interaction which is one of the recently focused areas in the field of disease diagnosis, pathogenesis and therapeutics. Such aggravated neuroinflammatory responses during PD are very well associated with augmented levels of cyclooxygenase (COX). An increased expression of cyclooxygenase (COX) with a concomitant increase in the prostaglandin E2 (PGE2) levels has been observed during PD pathology. Ibuprofen is one of the non-steroidal anti-inflammatory drugs (NSAID) and clinically being used for PD patients. This review focuses on the neuroinflammatory responses during PD pathology as well as the effect of ibuprofen on various disease related signaling factors and mechanisms involving nitrosative stress, neurotransmission, neuronal communication and peroxisome proliferator-activated receptor-γ. Such mechanistic effect of ibuprofen has been mostly reported in experimental models of PD and clinical investigations are still required. Since oxidative neuronal death is one of the major neurodegenerative mechanisms in PD, the antioxidant capacity of ibuprofen along with its antidepressant effects have also been discussed. This review will direct the readers towards fulfilling the existing gaps in the mechanistic aspect of ibuprofen and enhance its clinical relevance in PD therapeutics and probably in other age-related neurodegenerative diseases.
Subject(s)
Ibuprofen/pharmacology , Inflammation/drug therapy , Parkinson Disease/drug therapy , Animals , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Antioxidants/pharmacology , Humans , Inflammation/physiopathology , Neuroglia/metabolism , Neurons/pathology , Parkinson Disease/physiopathology , Parkinsonian Disorders/drug therapy , Parkinsonian Disorders/physiopathology , Prostaglandin-Endoperoxide Synthases/metabolismABSTRACT
Parkinson's disease (PD) is a slow progressive, second most common neurodegenerative disease characterized by the loss of dopaminergic neurons from the nigrostriatal pathway. In spite of extensive research the therapeutics options of disease are limited which only offer symptomatic relief and could not prevent the disease progression. Therefore researchers are looking for the probable synthetic or natural compounds for the PD therapeutics. Due to mandatory chronic consumption of anti PD drug to the PD patients, the natural compounds are getting attention recently. Numerous studies have indicated the neuroprotective effects of natural polyphenols including epigallocatechin, quercetin, baicalein, resveratrol, luteolin, curcumin, puerarin, genistein, hyperoside naringin against dopaminergic neuronal death with relatively safe with uncommon, mild or transient side effects. However, their mechanistic interference in dopaminergic neuronal death mechanism is not very well defined. Herein, we have attempted to discuss the various natural polyphenols with their known effects on various PD related pathologies to understand their therapeutic utilization for PD patients either in prophylactic or therapeutic mode. Briefly we have also discussed the major disease mechanisms which could be targeted for utilization of these polyphenols specifically involving oxidative stress and mitochondrial dysfunction. We have also discuss the limitation and probable strategies for the clinical utilization of these polyphenols for the benefit of PD patients.
Subject(s)
Antioxidants/therapeutic use , Neuroprotective Agents/therapeutic use , Parkinson Disease/drug therapy , Polyphenols/therapeutic use , Animals , Brain/drug effects , Cell Line, Tumor , HumansABSTRACT
Arsenic (As) is a serious threat for environment and human health. Rice, the main staple crop is more prone to As uptake. Bioremediation strategies with heavy metal tolerant rhizobacteria are well known. The main objective of the study was to characterize arsenic-resistant yeast strains, capable of mitigating arsenic stress in rice. Three yeast strains identified as Debaryomyces hansenii (NBRI-Sh2.11), Candida tropicalis (NBRI-B3.4) and Candida dubliniensis (NBRI-3.5) were found to have As reductase activity. D. hansenii with higher As tolerance has As expulsion ability as compared to other two strains. Inoculation of D. hansenii showed improved detoxification through scavenging of reactive oxygen species (ROS) by the modulation of SOD and APX activity under As stress condition in rice. Modulation of defense responsive gene (NADPH, GST, GR) along with arsR and metal cation transporter are the probable mechanism of As detoxification as evident with improved membrane (electrolyte leakage) stability. Reduced grain As (~40% reduction) due to interaction with D. hansenii (NBRI-Sh2.11) further validated it's As mitigation property in rice. To the best of our knowledge D. hansenii has been reported for the first time for arsenic stress mitigation in rice with improved growth and nutrient status of the plant.
Subject(s)
Arsenic/toxicity , Debaryomyces/enzymology , Oryza/drug effects , Agricultural Inoculants , Arsenate Reductases/metabolism , Arsenic/metabolism , Biodegradation, Environmental , Candida/enzymology , Debaryomyces/drug effects , Debaryomyces/genetics , Debaryomyces/metabolism , Oryza/growth & development , Reactive Oxygen Species/metabolismABSTRACT
Arsenic (As) contamination of paddy rice is a serious threat all over the world particularly in South East Asia. Selenium (Se) plays important role in protection of plants against various abiotic stresses including heavy metals. Moreover, arsenite (AsIII) and selenite (SeIV) can be biologically antagonistic due to similar electronic configuration and sharing the common transporter for their uptake in plant. In the present study, the response of oxidative stress, phenolic compounds and nutrient elements was analyzed to investigate Se mediated As tolerance in rice seedlings during AsIII and SeIV exposure in hydroponics. Selenite (25µM) significantly decreased As accumulation in plant than As (25µM) alone treated plants. Level of oxidative stress related parameters viz., reactive oxygen species (ROS), lipid peroxidation, electrical conductivity, nitric oxide and pro-oxidant enzyme (NADPH oxidase), were in the order of As>As+Se>control>Se. Selenium ameliorated As phytotoxicity by increased level of phenolic compounds particularly gallic acid, protocatechuic acid, ferulic acid and rutin and thiol metabolism related enzymes viz., serine acetyl transferase (SAT) and cysteine synthase (CS). Selenium supplementation enhanced the uptake of nutrient elements viz., Fe, Mn, Co, Cu, Zn, Mo, and improved plant growth. The results concluded that Se addition in As contaminated environment might be an important strategy to reduce As uptake and associated phytotoxicity in rice plant by modulation of phenolic compounds and increased uptake of nutrient elements.
Subject(s)
Arsenic/toxicity , Oryza/drug effects , Sodium Selenite/pharmacology , Teratogens/toxicity , Water Pollutants, Chemical/toxicity , Arsenic/metabolism , Arsenites/toxicity , Lipid Peroxidation/drug effects , Metals, Heavy/metabolism , NADPH Oxidases/metabolism , Oryza/metabolism , Oxidative Stress/drug effects , Phenols/metabolism , Plant Roots/metabolism , Reactive Oxygen Species/metabolism , Seedlings/metabolism , Sulfhydryl Compounds/metabolism , Water Pollutants, Chemical/metabolismABSTRACT
Trichoderma reesei is an industrially important fungi which also imparts stress tolerance and plant growth promotion in various crops. Arsenic (As) contamination of field soils is one of the challenging problems in agriculture, posing potential threats for both human health and the environment. Plants in association with microbes are a liable method to improve metal tolerance and enhance crop productivity. Chickpea (Cicer arietinum L.), is an important grain legume providing cheap source of protein in semi-arid regions including As affected areas. In this study we report the role of T. reesei NBRI 0716 (NBRI 0716) in supporting chickpea growth and improving soil quality in As simulated conditions. NBRI 0716 modulated the As speciation and its availability to improve grain yield and quality (amino acids and mineral content) in chickpea (C. arietinum L.) plants grown in As spiked soil (100 mg As kg(-1) soil). Arsenic accumulation and speciation results indicate that arsenate [As(V)] was the dominant species in chickpea seeds and rhizosphere soil. The Trichoderma reduced total grain inorganic As (Asi) by 66% and enhanced dimethylarsonic acid (DMA) and monomethylarsinic acid (MMA) content of seed and rhizosphere soil. The results indicate a probable role of NBRI 0716 in As methylation as the possible mechanism for maneuvering As stress in chickpea. Analysis of functional diversity using carbon source utilization (Biolog) showed significant difference in diversity and evenness indices among the soil microbial rhizosphere communities. Microbial diversity loss caused by As were prevented in the presence of Trichoderma NBRI 0716.
Subject(s)
Amino Acids/metabolism , Arsenic/metabolism , Cicer/microbiology , Edible Grain/metabolism , Trichoderma/physiology , Agriculture , Cicer/growth & development , Cicer/metabolism , Crops, Agricultural , Humans , Metals/analysis , Microbial Consortia , Minerals/metabolism , Proteins/metabolism , Rhizosphere , Seeds/metabolism , SoilABSTRACT
Astroglia from the postnatal cerebral cortex can be reprogrammed in vitro to generate neurons following forced expression of neurogenic transcription factors, thus opening new avenues towards a potential use of endogenous astroglia for brain repair. However, in previous attempts astroglia-derived neurons failed to establish functional synapses, a severe limitation towards functional neurogenesis. It remained therefore also unknown whether neurons derived from reprogrammed astroglia could be directed towards distinct neuronal subtype identities by selective expression of distinct neurogenic fate determinants. Here we show that strong and persistent expression of neurogenic fate determinants driven by silencing-resistant retroviral vectors instructs astroglia from the postnatal cortex in vitro to mature into fully functional, synapse-forming neurons. Importantly, the neurotransmitter fate choice of astroglia-derived neurons can be controlled by selective expression of distinct neurogenic transcription factors: forced expression of the dorsal telencephalic fate determinant neurogenin-2 (Neurog2) directs cortical astroglia to generate synapse-forming glutamatergic neurons; in contrast, the ventral telencephalic fate determinant Dlx2 induces a GABAergic identity, although the overall efficiency of Dlx2-mediated neuronal reprogramming is much lower compared to Neurog2, suggesting that cortical astroglia possess a higher competence to respond to the dorsal telencephalic fate determinant. Interestingly, however, reprogramming of astroglia towards the generation of GABAergic neurons was greatly facilitated when the astroglial cells were first expanded as neurosphere cells prior to transduction with Dlx2. Importantly, this approach of expansion under neurosphere conditions and subsequent reprogramming with distinct neurogenic transcription factors can also be extended to reactive astroglia isolated from the adult injured cerebral cortex, allowing for the selective generation of glutamatergic or GABAergic neurons. These data provide evidence that cortical astroglia can undergo a conversion across cell lineages by forced expression of a single neurogenic transcription factor, stably generating fully differentiated neurons. Moreover, neuronal reprogramming of astroglia is not restricted to postnatal stages but can also be achieved from terminally differentiated astroglia of the adult cerebral cortex following injury-induced reactivation.
Subject(s)
Astrocytes/cytology , Cell Differentiation , Cerebral Cortex/cytology , Neurogenesis/physiology , Neuroglia/physiology , Neurons/cytology , Adult , Animals , Astrocytes/virology , Basic Helix-Loop-Helix Transcription Factors/genetics , Basic Helix-Loop-Helix Transcription Factors/metabolism , Cells, Cultured , Cerebral Cortex/embryology , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Humans , Mice , Mice, Inbred C57BL , Mice, Transgenic , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Neuroglia/cytology , Neuroglia/virology , Retroviridae/genetics , Stem Cells/cytology , Stem Cells/physiology , Synapses/physiology , Transcription Factors/genetics , Transcription Factors/metabolism , Transduction, Genetic/methodsABSTRACT
Arsenic, a carcinogenic metalloid severely affects plant growth in contaminated areas. Present study shows role of Trichoderma reesei NBRI 0716 (NBRI 0716) in ameliorating arsenic (As) stress on chickpea under greenhouse conditions. Arsenic stress adversely affected seed germination (25%), chlorophyll content (44%) and almost eliminated nodule formation that were significantly restored on NBRI 0716 inoculation. It also restored stem anomalies like reduced trichome turgidity and density, deformation in collenchymatous and sclerenchymatous cells induced by As stress. Semi-quantitative RT-PCR of stress responsive genes showed differential expression of genes involved in synthesis of cell wall degrading enzymes, dormancy termination and abiotic stress. Upregulation of drought responsive genes (DRE, EREBP, T6PS, MIPS, and PGIP), enhanced proline content and shrunken cortex cells in the presence of As suggests that it creates water deficiency in plants and these responses were modulated by NBRI 0716 which provides a protective role. NBRI0716 mediated production of As reductase enzyme in chickpea and thus contributed in As metabolism. The study suggests a multifarious role of NBRI0716 in mediating stress tolerance in chickpea towards As.
Subject(s)
Arsenic/toxicity , Cicer/drug effects , Cicer/microbiology , Gene Expression Regulation, Plant , Plant Stems/cytology , Trichoderma/physiology , Cicer/anatomy & histology , Cicer/genetics , Cicer/growth & development , Gene Expression Regulation, Plant/drug effects , Hydrogen-Ion Concentration , Plant Roots/drug effects , Plant Roots/growth & development , Plant Roots/microbiology , Plant Stems/drug effects , Plant Stems/microbiology , Soil/chemistry , Soil Pollutants/toxicityABSTRACT
Chlorpyrifos (CP), a broad-spectrum organophosphorus insecticide, is known for deleterious effects on soil enzymatic activities. Hence, the present study aims to examine the resilience effect of biochar (BC) aided Pelargonium graveolens L. plantation on enzymatic activities of chlorpyrifos contaminated soil. The two chlorpyrifos contaminated agriculture soils (with concentrations: S1: 46.1 and S2: 95.5 mg kg-1) were taken for the pot experiment. The plant biomass, plant growth parameters, soil microbial biomass, and enzymatic activities such as alkaline phosphatase, N-acetyl glucosaminidase, aryl sulphatase, cellulase, ß-glucosidase, dehydrogenase, phenoloxidase, and peroxidase enzymes were examined. Ecoenzyme activities and their stoichiometry were used to enumerate the different indices including geometric mean, weighted mean, biochemical activity indices, integrated biological response, treated-soil quality index, and vector analysis in all treatments. The results of the study demonstrated that the biochar incorporation enhanced the tolerance of P. graveolens (from 42-45% to 55-67%) in chlorpyrifos contaminated soil and reduced the CP accumulation in plants. A reduction in the inhibitory effect of chlorpyrifos on soil enzymatic activities and plant growth by BC incorporation was observed along with an increase in the activities of ecoenzymes (16.7-18.6%) in soil. The investigation indicated more microbial investments in C and P than that in N acquisition under CP stress. The BC amendment catalyzed the activities of lignin and cellulose-degrading enzymes and enhanced nutrition acquisition. The CP contamination and BC amendment have no significant effect on the oil quality of P. graveolens. The study demonstrated that BC-aided P. graveolens plantation offers sustainable phytotechnology for CP contaminated soil with an economic return.
Subject(s)
Chlorpyrifos , Insecticides , Pelargonium , Soil Pollutants , Insecticides/analysis , Soil , Organophosphorus Compounds , Charcoal , Hydrolases , Soil Pollutants/analysisABSTRACT
Reactive gliosis is the universal reaction to brain injury, but the precise origin and subsequent fate of the glial cells reacting to injury are unknown. Astrocytes react to injury by hypertrophy and up-regulation of the glial-fibrillary acidic protein (GFAP). Whereas mature astrocytes do not normally divide, a subpopulation of the reactive GFAP(+) cells does so, prompting the question of whether the proliferating GFAP(+) cells arise from endogenous glial progenitors or from mature astrocytes that start to proliferate in response to brain injury. Here we show by genetic fate mapping and cell type-specific viral targeting that quiescent astrocytes start to proliferate after stab wound injury and contribute to the reactive gliosis and proliferating GFAP(+) cells. These proliferating astrocytes remain within their lineage in vivo, while a more favorable environment in vitro revealed their multipotency and capacity for self-renewal. Conversely, progenitors present in the adult mouse cerebral cortex labeled by NG2 or the receptor for the platelet-derived growth factor (PDGFRalpha) did not form neurospheres after (or before) brain injury. Taken together, the first fate-mapping analysis of astrocytes in the adult mouse cerebral cortex shows that some astrocytes acquire stem cell properties after injury and hence may provide a promising cell type to initiate repair after brain injury.
Subject(s)
Astrocytes/physiology , Brain Injuries/pathology , Gliosis/pathology , Pluripotent Stem Cells/cytology , Animals , Astrocytes/cytology , Cell Lineage , Cells, Cultured , Cerebral Cortex , Glial Fibrillary Acidic Protein , Mice , Mice, Inbred Strains , Wounds, StabABSTRACT
The presence of atrazine, a triazine herbicide, and its residues in agriculture soil poses a serious threat to human health and environment through accumulation in edible plant parts. Hence, the present study focused on atrazine induced stress amelioration of Andrographis paniculata, an important medicinal plant, by a plant growth promoting and atrazine degrading endophytic bacterium CIMAP-A7 inoculation. Atrazine has a non-significant effect at a lower dose while at a higher dose (lower: 25 and higher: 50 mg kg-1) 22 and 36% decrease in secondary metabolite content and plant dry weight of A. paniculata was recorded, respectively. Endophyte CIMAP-A7 inoculation significantly reduced atrazine soil content, by 78 and 51% at lower and a higher doses respectively, than their respective control treatments. Inoculation of CIMAP-A7 exhibited better plant growth in terms of increased total chlorophyll, carotenoid, protein, and metabolite content with reduced atrazine content under both atrazine contaminated and un-contaminated treatments. Atrazine induced oxidative stress in A. paniculata was also ameliorated by CIMAP-A7 by reducing stress enzymes, proline, and malondialdehyde accumulation under contaminated soil conditions than un-inoculated treatments. Furthermore, the presence of atrazine metabolites deisopropylatrazine (DIA) and desethylatrazine (DEA) strongly suggests a role of CIMAP-A7 in mineralization however, the absence of these metabolites in uninoculated soil and all plant samples were recorded. These findings advocate that the amelioration of atrazine induced stress with no/least pesticide content in plant tissues by plant-endophyte co-interactions would be efficient in the remediation of atrazine contaminated soils and ensure safe crop produce.
Subject(s)
Andrographis , Atrazine , Herbicides , Soil Pollutants , Atrazine/analysis , Atrazine/toxicity , Biodegradation, Environmental , Herbicides/toxicity , Humans , Soil , Soil Pollutants/analysis , Soil Pollutants/toxicityABSTRACT
The present study explores the differential responses of two genotypes (APwC: wild collection and APMS: mass selection line) of A. paniculata against the three application rates of arsenic (42, 126, and 200 mg kg-1). The oxidative enzymes, As accumulation in different tissues, plant growth, and content of pharmacologically important ent-labdane-related diterpenes (ent-LRDs) of the two genotypes were evaluated in the study. Results demonstrated that As uptake significantly reduced plant biomass in APwC and APMS by 5-41.5% and 9-33% in a dose-response manner, respectively. The APMS exhibited lower bioconcentration and translocation factors, higher As tolerance index, and higher content of ent-LRDs as compared to APWC. As treatment induced a decrease in the sum of four metabolite content of APMS (1.43 times) and an increase in that of APWC (1.12 times) as compared to control. Likewise, variance in the production of 5,7,2',3'-tetramethoxyflavanone, and stress enzymes was also observed between APwC and APMS. The increase in the expression of ApCPS2 suggested its involvement in channeling of metabolic flux towards the biosynthesis of ent-LRDs under As stress.
Subject(s)
Andrographis , Arsenic , Diterpenes , Arsenic/toxicity , Genotype , Oxidative Stress/genetics , Plant ExtractsABSTRACT
The oily fraction (non polar fraction-NPF) of S. anacardium (SA) significantly increased the expression of protein kinase C-delta (PKC-delta) in macrophages in concentration dependent manner, which was similar to phorbol myristate acetate (PMA) response. Further, H-7 (1-(5-isoquinolinesulphonyl)-2-methylpiperazine), an inhibitor of PKC significantly inhibited this NPF mediated response in a concentration dependent manner. In the post treatment kinetics, H-7 showed this inhibition only up to 6 min post NPF/PMA addition, but in similar condition, quercetin, a flavone with reported antioxidant property, showed this inhibition only up to 2 min. The results clearly suggest that oily fraction of SA nuts enhances the expression of PKC protein, which may be responsible for its reported pro-inflammatory property.
Subject(s)
Enzyme Activation/drug effects , Macrophages, Peritoneal/drug effects , Nuts/chemistry , Plant Extracts/pharmacology , Protein Kinase C-delta/metabolism , Semecarpus/chemistry , 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine/pharmacology , Animals , Antioxidants/pharmacology , Carcinogens/pharmacology , Cells, Cultured , Enzyme Inhibitors/pharmacology , Nitric Oxide Synthase Type II/metabolism , Protein Kinase C-delta/antagonists & inhibitors , Quercetin/pharmacology , Rats , Signal Transduction/drug effects , Tetradecanoylphorbol Acetate/pharmacologyABSTRACT
Fungi mediated arsenic (As) stress modulation has emerged as an important strategy for the mitigation of As mediated stress management in plants for reducing As contamination to the food chain. In the present study, total of 45 fungal strains were isolated from the three As contaminated sites of West Bengal, India. These strains were morphologically different and inhibited variable As tolerance (10 to 5000 mg l-1As). Total 21 fungal isolates, tolerant up to 5000 mg l-1 AsV, were investigated for As removal (10 mg l-1 As) after 21 d of cultivation under laboratory conditions. The As bioaccumulation in fungal biomass ranged between 0.146 to 11.36 g kg-1 biomass. Range of volatilized As was between 0.05 to 53.39 mg kg-1 biomass. Most promising bioaccumulation and biovolatilization potential were observed in strains viz., 2WS1, 3WS1 and 2WS9. Strain 2WS1 showed highest As biovolatilization (53.39 mg kg-1 biomass) and was identified as Humicola sp. using ITS/5.8S rDNA gene sequencing. This is the first report of Humicola sp. having As biomethylation property. Best first 8 As biomethylating fungal strains were further tested for their As remediation and PGP potential in Bacopa monnieri plant grown in As contaminated soil (20 mg kg-1) in a pot experiment under greenhouse conditions. The highest leaf stem ratio and lowest As content in leaf tissues were observed in 2WS1 inoculated Bacopa monnieri plants. The presence of arsM gene in 2WS1 strain suggests As biovolatilization as possible bioremediation and As stress mitigation strategy of 2WS1. Therefore, application of this strain of Humicola sp. strain 2WS1 in As contaminated soils could be a potential and realistic mitigation strategy for reducing As contamination to cropping system coupled with enhanced productivity.
Subject(s)
Bacopa , Arsenic , Biodegradation, Environmental , India , Soil , Soil PollutantsABSTRACT
Cellular identity is ultimately dictated by the interaction of transcription factors with regulatory elements (REs) to control gene expression. Advances in epigenome profiling techniques have significantly increased our understanding of cell-specific utilization of REs. However, it remains difficult to dissect the majority of factors that interact with these REs due to the lack of appropriate techniques. Therefore, we developed TINC: TALE-mediated isolation of nuclear chromatin. Using this new method, we interrogated the protein complex formed at the Nanog promoter in embryonic stem cells (ESCs) and identified many known and previously unknown interactors, including RCOR2. Further interrogation of the role of RCOR2 in ESCs revealed its involvement in the repression of lineage genes and the fine-tuning of pluripotency genes. Consequently, using the Nanog promoter as a paradigm, we demonstrated the power of TINC to provide insight into the molecular makeup of specific transcriptional complexes at individual REs as well as into cellular identity control in general.
Subject(s)
Genetic Loci , Human Embryonic Stem Cells/metabolism , Multiprotein Complexes/metabolism , Nanog Homeobox Protein/metabolism , Co-Repressor Proteins/metabolism , Human Embryonic Stem Cells/cytology , HumansABSTRACT
Cu(II), Fe(III), and Mn(II) complexes of a novel ligand N'-[(4-methoxy)thiobenzoyl]benzoic acid hydrazide (H(2)mtbh) have been synthesized and characterized by elemental analyses, IR, UV-vis, NMR, mass, EPR and Mössbauer spectroscopy. The results suggest a square planar structure for [Cu(Hmtbh)Cl] and [Cu(mtbh)] whereas an octahedral structure for [Mn(Hmtbh)(2)] and [Fe(Hmtbh)(mtbh)]. Mn(II) and Fe(III) complexes were found to inhibit proliferation of HT29 cells. [Mn(Hmtbh)(2)] and [Fe(Hmtbh)(mtbh)] inhibited proliferation of HT29 cells with half maximal inhibition (IC(50)) of 8.15+/-0.87 and 68.1+/-4.8 microM, respectively, whereas H(2)mtbh showed growth inhibition with IC(50) of 90.9+/-7.8 microM and were able to inhibit NMT activity in vitro. Mn(II) and Fe(III) complexes inhibited NMT activity in a dose dependent manner with IC(50) values of 20+/-2.2 and 60+/-7.2 microM, respectively, whereas ligand (H(2)mtbh) displayed IC(50) of 3.2+/-0.5 mM.