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KEY MESSAGE: miR6024 acts as a negative regulator of R genes, hence of Tomato plant immunity, and facilitates disease by the necrotrophic pathogen A. solani. Plant resistance genes or Nucleotide-binding leucine-rich repeat (NLR) genes, integral components of plant disease stress-signaling are targeted by variable groups of miRNAs. However, the significance of miRNA-mediated regulation of NLRs during a pathogen stress response, specifically for necrotrophic fungus, is poorly understood. A thorough examination of Tomato NLRs and miRNAs could map substantial interactions of which half the annotated NLRs were targets of Solanaceae-specific and conserved miRNAs, at the NB subdomain. The Solanaceae-specific miR6024 and its NLR targets analysed in different phytopathogenic stresses revealed differential and mutually antagonistic regulation. Interestingly, miR6024-targeted cleavage of a target NLR also triggered the generation of secondary phased siRNAs which could potentially amplify the defense signal. RNA-seq analysis of leaf tissues from miR6024 overexpressing Tomato plants evidenced a perturbation in the defense transcriptome with the transgenics showing unwarranted immune response-related genes' expression with or without infection with necrotrophic Alternaria solani, though no adverse effect could be observed in the growth and development of the transgenic plants. Transgenic plants exhibited constitutive downregulation of the target NLRs, aggravated disease phenotype with an enhanced lesion, greater ROS generation and hypersusceptibility to A. solani infection, thus establishing that miR6024 negatively impacts plant immune response during necrotrophic pathogenesis. Limited knowledge about the outcome of NLR-miRNA interaction during necrotrophic pathogenesis is a hindrance to the deployment of miRNAs in crop improvement programs. With the elucidation of the necrotrophic disease-synergistic role played by miR6024, it becomes a potent candidate for biotechnological manipulation for the rapid development of pathogen-tolerant solanaceous plants.
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MicroARNs , Solanum lycopersicum , Solanum lycopersicum/microbiología , MicroARNs/genética , MicroARNs/metabolismo , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Inmunidad de la Planta , Plantas Modificadas Genéticamente/genéticaRESUMEN
PIWI interacting RNAs (piRNAs) have emerged as important gene regulators in recent times. Since the release of our first version of piRNAQuest in 2014, lots of novel piRNAs have been annotated in different species other than human, mouse and rat. Such new developments in piRNA research have led us to develop an updated database piRNAQuest V.2. It consists of 92,77,689 piRNA entries for 25 new species of different phylum along with human, mouse and rat. Besides providing primary piRNA features which include their genomic location, with further information on piRNAs overlapping with repeat elements, pseudogenes and syntenic regions, etc., the novel features of this version includes (i) density based cluster prediction, (ii) piRNA expression profile across various healthy and disease systems and (iii) piRNA target prediction. The concept of density-based piRNA cluster identification is robust as it does not consider parametric distribution in its model. The piRNA expression profile for 21 disease systems including cancer have been hosted in addition to 32 tissue specific piRNA expression profile for various species. Further, the piRNA target prediction section includes both predicted and curated piRNA targets within eight disease systems and developmental stages of mouse testis. Further, users can visualize the piRNA-target duplex structure and the ping-pong signature pattern for all the ping-pong piRNA partners in different species. Overall, piRNAQuest V.2 is an updated user-friendly database which will serve as a useful resource to survey, search and retrieve information on piRNAs for multiple species. This freely accessible database is available at http://dibresources.jcbose.ac.in/zhumur/pirnaquest2.
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Biología Computacional/métodos , Perfilación de la Expresión Génica/métodos , ARN Interferente Pequeño/genética , Programas Informáticos , Transcriptoma , Animales , Mapeo Cromosómico , Bases de Datos Genéticas , Amplificación de Genes , Genómica/métodos , Humanos , Especificidad de Órganos , Secuencias Repetitivas de Ácidos Nucleicos , Especificidad de la Especie , Navegador WebRESUMEN
BACKGROUND: Human Chronic and Acute Myeloid Leukemia are myeloproliferative disorders in myeloid lineage of blood cells characterized by accumulation of aberrant white blood cells. In cancer, the anomalous transcriptome includes deregulated expression of non-coding RNAs in conjunction with protein-coding mRNAs in human genome. The coding or non-coding RNA transcripts harboring miRNA-binding sites can converse with and regulate each other by explicitly contending for a limited pool of shared miRNAs and act as competitive endogenous RNAs (ceRNAs). An unifying hypothesis attributing 'modulation of expression of transcripts' in this fashion had been defined as 'competitive endogenous RNA hypothesis'. Network built with ceRNAs evidently offers a platform to elucidate complex regulatory interactions at post-transcriptional level in human cancers. METHODS: Contemplating cancers of human myeloid lineage we constructed ceRNA networks for CML and AML coding and non-coding repertoire utilizing patient sample data. Through functional enrichment analysis we selected the significant functional modules for transcripts being differentially expressed in Blastic phases of each cancer types with respect to Normal. After retrieving free energy of binding and duplex formation of shared miRNAs on ceRNAs, we performed statistical averaging of energy values over the ensemble of populations considering cellular system as in canonical (Iso-thermal) situation. RESULTS AND CONCLUSIONS: We aimed to shed light on 'Sibling Rivalry' in ceRNA partners from the perspective of statistical thermodynamics, identified major cross-talking tracks and ceRNAs influencing transcripts concerned in myeloid cancer systems. GENERAL SIGNIFICANCE: Insights into ceRNA-regulation will shed light on progression and prognosis of human Chronic and Acute Myeloid Leukemia.
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Biomarcadores de Tumor/genética , Redes Reguladoras de Genes , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Leucemia Mieloide Aguda/genética , MicroARNs/genética , ARN Largo no Codificante/genética , ARN Mensajero/genética , Estudios de Casos y Controles , Bases de Datos Factuales , Regulación Neoplásica de la Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , TranscriptomaRESUMEN
BACKGROUND: High-throughput Next-Generation Sequencing (NGS) techniques are advancing genomics and molecular biology research. This technology generates substantially large data which puts up a major challenge to the scientists for an efficient, cost and time effective solution to analyse such data. Further, for the different types of NGS data, there are certain common challenging steps involved in analysing those data. Spliced alignment is one such fundamental step in NGS data analysis which is extremely computational intensive as well as time consuming. There exists serious problem even with the most widely used spliced alignment tools. TopHat is one such widely used spliced alignment tools which although supports multithreading, does not efficiently utilize computational resources in terms of CPU utilization and memory. Here we have introduced PVT (Pipelined Version of TopHat) where we take up a modular approach by breaking TopHat's serial execution into a pipeline of multiple stages, thereby increasing the degree of parallelization and computational resource utilization. Thus we address the discrepancies in TopHat so as to analyze large NGS data efficiently. RESULTS: We analysed the SRA dataset (SRX026839 and SRX026838) consisting of single end reads and SRA data SRR1027730 consisting of paired-end reads. We used TopHat v2.0.8 to analyse these datasets and noted the CPU usage, memory footprint and execution time during spliced alignment. With this basic information, we designed PVT, a pipelined version of TopHat that removes the redundant computational steps during 'spliced alignment' and breaks the job into a pipeline of multiple stages (each comprising of different step(s)) to improve its resource utilization, thus reducing the execution time. CONCLUSIONS: PVT provides an improvement over TopHat for spliced alignment of NGS data analysis. PVT thus resulted in the reduction of the execution time to ~23% for the single end read dataset. Further, PVT designed for paired end reads showed an improved performance of ~41% over TopHat (for the chosen data) with respect to execution time. Moreover we propose PVT-Cloud which implements PVT pipeline in cloud computing system.
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Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Genómica/métodos , Humanos , Programas Informáticos , Factores de TiempoRESUMEN
BACKGROUND: PIWI-interacting RNA (piRNA) is a novel and emerging class of small non-coding RNA (sncRNA). Ranging in length from 26-32 nucleotides, this sncRNA is a potent player in guiding the vital regulatory processes within a cellular system. Inspite of having such a wide role within cellular systems, piRNAs are not well organized and classified, so that a researcher can pool out the biologically relevant information concerning this class. DESCRIPTION: Here we present piRNAQuest- a unified and comprehensive database of 41749 human, 890078 mouse and 66758 rat piRNAs obtained from NCBI and different small RNA sequence experiments. This database provides piRNA annotation based on their localization in gene, intron, intergenic, CDS, 5/UTR, 3/UTR and repetitive regions which has not been done so far. We have also annotated piRNA clusters and have elucidated characteristic motifs within them. We have looked for the presence of piRNAs and piRNA clusters in pseudogenes, which are known to regulate the expression of protein coding transcripts by generating small RNAs. All these will help researchers progress towards solving the unanswered queries on piRNA biogenesis and their mode of action. Further, expression profile for piRNA in different tissues and from different developmental stages has been provided. In addition, we have provided several tools like 'homology search', 'dynamic cluster search' and 'pattern search'. Overall, piRNAQuest will serve as a useful resource for exploring human, mouse and rat piRNAome. The database is freely accessible and available at http://bicresources.jcbose.ac.in/zhumur/pirnaquest/. CONCLUSION: piRNAs play a remarkable role in stem cell self-renewal and various vital processes of developmental biology. Although researchers are mining different features on piRNAs, the exact regulatory mechanism is still fuzzy. Thus, understanding the true potential of these small regulatory molecules with respect to their origin, localization and mode of biogenesis is crucial. piRNAQuest will provide us with a better insight on piRNA origin and function which will help to explore the true potential of these sncRNAs.
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Bases de Datos de Ácidos Nucleicos , ARN Interferente Pequeño/genética , Animales , Elementos Transponibles de ADN , Humanos , Ratones , Anotación de Secuencia Molecular , Familia de Multigenes , Interferencia de ARN , ARN Interferente Pequeño/clasificación , Ratas , Secuencias Repetitivas de Ácidos Nucleicos , TranscriptomaRESUMEN
Interleukin-6 (IL-6) is a major pro-inflammatory cytokine for which the levels in plasma demonstrate a robust correlation with age and body mass index (BMI) as part of the senescence-associated secretory phenotype. IL-6 cytokines also play a crucial role in metabolic homeostasis and regenerative processes, primarily via the canonical STAT3 pathway. Thus, selective modulation of IL-6 signaling may offer a unique opportunity for therapeutic interventions. Recently, we discovered that a non-canonical signaling pathway downstream of tyrosine (Y) 814 within the intracellular domain of gp130, the IL-6 co-receptor, is responsible for the recruitment and activation of SRC family of kinases (SFK). Mice with constitutive genetic inactivation of gp130 Y814 (F814 mice) show accelerated resolution of inflammatory response and superior regenerative outcomes in skin wound healing and posttraumatic models of osteoarthritis. The current study was designed to explore if selective genetic or pharmacological inhibition of the non-canonical gp130-Y814/SFK signaling reduces systemic chronic inflammation and multimorbidity in a high-fat diet (HFD)-induced model of accelerated aging. F814 mice showed significantly reduced inflammatory response to HFD in adipose and liver tissue, with significantly reduced levels of systemic inflammation compared to wild type mice. F814 mice were also protected from HFD-induced bone loss and cartilage degeneration. Pharmacological inhibition of gp130-Y814/SFK in mice on HFD mirrored the effects observed in F814 mice on HFD; furthermore, this pharmacological treatment also demonstrated a marked increase in physical activity levels and protective effects against inflammation-associated suppression of neurogenesis in the brain tissue compared to the control group. These findings suggest that selective inhibition of SFK signaling downstream of gp130 receptor represents a promising strategy to alleviate systemic chronic inflammation. Increased degenerative changes and tissue senescence are inevitable in obese and aged organisms, but we demonstrated that the systemic response and inflammation-associated multi-morbidity can be therapeutically mitigated.
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Acute Myeloid Leukemia (AML) can be detected based on morphology, cytochemistry, immunological markers, and cytogenetics. MicroRNAs (miRNAs) influence key biological pathways in multiple haematological malignancies including AML. In this work, we have analysed the miRNome and the transcriptome of normal and AML samples and have identified the significant set of miRNA-target mRNA pairs present within AML- Peripheral Blood and AML- Bone Marrow samples from both tissue and cell lines. The miRNA target genes are further filtered based on their functional significance in AML system. These filtered genes constitute the set of selected miRNA target features, which have been finally used for developing machine learning based prediction tool, 'TbAMLPred' for preliminary detection of AML. This model implements both unsupervised clustering and supervised classification algorithms that would increase the reliability of prediction. Our results show that the selected miRNA target-based features can separate the control and disease samples linearly. Overall, we put forward 'TbAMLPred' for a non-invasive mode of preliminary AML diagnosis in future. Github link for accessing TbAMLPred: https://github.com/zglabDIB/TbAMLPred.
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Leucemia Mieloide Aguda , MicroARNs , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Reproducibilidad de los Resultados , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Línea Celular , Redes Reguladoras de Genes/genéticaRESUMEN
Epigenetic mechanisms guiding articular cartilage regeneration and age-related disease such as osteoarthritis (OA) are poorly understood. STAT3 is a critical age-patterned transcription factor highly active in fetal and OA chondrocytes, but the context-specific role of STAT3 in regulating the epigenome of cartilage cells remain elusive. In this study, DNA methylation profiling was performed across human chondrocyte ontogeny to build an epigenetic clock and establish an association between CpG methylation and human chondrocyte age. Exposure of adult chondrocytes to a small molecule STAT3 agonist decreased DNA methylation, while genetic ablation of STAT3 in fetal chondrocytes induced global hypermethylation. CUT&RUN assay and subsequent transcriptional validation revealed DNA methyltransferase 3 beta (DNMT3B) as one of the putative STAT3 targets in chondrocyte development and OA. Functional assessment of human OA chondrocytes showed the acquisition of progenitor-like immature phenotype by a significant subset of cells. Finally, conditional deletion of Stat3 in cartilage cells increased DNMT3B expression in articular chondrocytes in the knee joint in vivo and resulted in a more prominent OA progression in a post-traumatic OA (PTOA) mouse model induced by destabilization of the medial meniscus (DMM). Taken together these data reveal a novel role for STAT3 in regulating DNA methylation in cartilage development and disease. Our findings also suggest that elevated levels of active STAT3 in OA chondrocytes may indicate an intrinsic attempt of the tissue to regenerate by promoting a progenitor-like phenotype. However, it is likely that chronic activation of this pathway, induced by IL-6 cytokines, is detrimental and leads to tissue degeneration.
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Cartílago Articular , Osteoartritis , Ratones , Animales , Humanos , Condrocitos/metabolismo , Células Cultivadas , Osteoartritis/genética , Osteoartritis/metabolismo , Cartílago Articular/metabolismo , Epigénesis Genética , Metilación de ADN/genética , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismoRESUMEN
Adult mammals are incapable of multitissue regeneration, and augmentation of this potential may shift current therapeutic paradigms. We found that a common co-receptor of interleukin 6 (IL-6) cytokines, glycoprotein 130 (gp130), serves as a major nexus integrating various context-specific signaling inputs to either promote regenerative outcomes or aggravate disease progression. Via genetic and pharmacological experiments in vitro and in vivo, we demonstrated that a signaling tyrosine 814 (Y814) within gp130 serves as a major cellular stress sensor. Mice with constitutively inactivated Y814 (F814) were resistant to surgically induced osteoarthritis as reflected by reduced loss of proteoglycans, reduced synovitis, and synovial fibrosis. The F814 mice also exhibited enhanced regenerative, not reparative, responses after wounding in the skin. In addition, pharmacological modulation of gp130 Y814 upstream of the SRC and MAPK circuit by a small molecule, R805, elicited a protective effect on tissues after injury. Topical administration of R805 on mouse skin wounds resulted in enhanced hair follicle neogenesis and dermal regeneration. Intra-articular administration of R805 to rats after medial meniscal tear and to canines after arthroscopic meniscal release markedly mitigated the appearance of osteoarthritis. Single-cell sequencing data demonstrated that genetic and pharmacological modulation of Y814 resulted in attenuation of inflammatory gene signature as visualized by the anti-inflammatory macrophage and nonpathological fibroblast subpopulations in the skin and joint tissue after injury. Together, our study characterized a molecular mechanism that, if manipulated, enhances the intrinsic regenerative capacity of tissues through suppression of a proinflammatory milieu and prevents pathological outcomes in injury and disease.
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Citocinas , Osteoartritis , Ratones , Ratas , Animales , Perros , Receptor gp130 de Citocinas , Interleucina-6 , Proteoglicanos , MamíferosRESUMEN
Growth of long bones and vertebrae is maintained postnatally by a long-lasting pool of progenitor cells. Little is known about the molecular mechanisms that regulate the output and maintenance of the cells that give rise to mature cartilage. Here we demonstrate that postnatal chondrocyte-specific deletion of a transcription factor Stat3 results in severely reduced proliferation coupled with increased hypertrophy, growth plate fusion, stunting and signs of progressive dysfunction of the articular cartilage. This effect is dimorphic, with females more strongly affected than males. Chondrocyte-specific deletion of the IL-6 family cytokine receptor gp130, which activates Stat3, phenocopied Stat3-deletion; deletion of Lifr, one of many co-receptors that signals through gp130, resulted in a milder phenotype. These data define a molecular circuit that regulates chondrogenic cell maintenance and output and reveals a pivotal positive function of IL-6 family cytokines in the skeletal system with direct implications for skeletal development and regeneration.
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Condrocitos/metabolismo , Receptor gp130 de Citocinas/genética , Placa de Crecimiento/metabolismo , Ratones/genética , Factor de Transcripción STAT3/genética , Animales , Proliferación Celular/genética , Receptor gp130 de Citocinas/metabolismo , Homeostasis/genética , Ratones/crecimiento & desarrollo , Factor de Transcripción STAT3/metabolismoRESUMEN
Cartilage tissue is comprised of extracellular matrix and chondrocytes, a cell type with very low cellular turnover in adults, providing limited capacity for regeneration. However, in development a significant number of chondrocytes actively proliferate and remodel the surrounding matrix. Uncoupling the microenvironmental influences that determine the balance between clonogenic potential and terminal differentiation of these cells is essential for the development of novel approaches for cartilage regeneration. Unfortunately, most of the existing methods are not applicable for the analysis of functional properties of chondrocytes at a single cell resolution. Here we demonstrate that a novel 3D culture method provides a long-term and permissive in vitro niche that selects for highly clonogenic, colony-forming chondrocytes which maintain cartilage-specific matrix production, thus recapitulating the in vivo niche. As a proof of concept, clonogenicity of Sox9 IRES-EGFP mouse chondrocytes is almost exclusively found in the highest GFP+ fraction known to be enriched for chondrocyte progenitor cells. Although clonogenic chondrocytes are very rare in adult cartilage, we have optimized this system to support large, single cell-derived chondrogenic organoids with complex zonal architecture and robust chondrogenic phenotype from adult pig and human articular chondrocytes. Moreover, we have demonstrated that growth trajectory and matrix biosynthesis in these organoids respond to a pro-inflammatory environment. This culture method offers a robust, defined and controllable system that can be further used to interrogate the effects of various microenvironmental signals on chondrocytes, providing a high throughput platform to assess genetic and environmental factors in development and disease.
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Tissue regeneration is a process that recapitulates and restores organ structure and function. Although previous studies have demonstrated wound-induced hair neogenesis (WIHN) in laboratory mice (Mus), the regeneration is limited to the center of the wound unlike those observed in African spiny (Acomys) mice. Tissue mechanics have been implicated as an integral part of tissue morphogenesis. Here, we use the WIHN model to investigate the mechanical and molecular responses of laboratory and African spiny mice, and report these models demonstrate opposing trends in spatiotemporal morphogenetic field formation with association to wound stiffness landscapes. Transcriptome analysis and K14-Cre-Twist1 transgenic mice show the Twist1 pathway acts as a mediator for both epidermal-dermal interactions and a competence factor for periodic patterning, differing from those used in development. We propose a Turing model based on tissue stiffness that supports a two-scale tissue mechanics process: (1) establishing a morphogenetic field within the wound bed (mm scale) and (2) symmetry breaking of the epidermis and forming periodically arranged hair primordia within the morphogenetic field (µm scale). Thus, we delineate distinct chemo-mechanical events in building a Turing morphogenesis-competent field during WIHN of laboratory and African spiny mice and identify its evo-devo advantages with perspectives for regenerative medicine.
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Epidermis/anatomía & histología , Epidermis/metabolismo , Folículo Piloso/metabolismo , Morfogénesis/fisiología , Regeneración/fisiología , Proteína 1 Relacionada con Twist/metabolismo , Cicatrización de Heridas/fisiología , Animales , Epidermis/fisiología , Perfilación de la Expresión Génica , Folículo Piloso/anatomía & histología , Folículo Piloso/fisiología , Inmunohistoquímica , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Análisis por Micromatrices , Microscopía de Fuerza Atómica , Modelos Psicológicos , Morfogénesis/genética , Murinae , RNA-Seq , Regeneración/genética , Medicina Regenerativa , Transducción de Señal/genética , Transducción de Señal/fisiología , Análisis Espacio-Temporal , Proteína 1 Relacionada con Twist/genética , Cicatrización de Heridas/genéticaRESUMEN
Osteoarthritis (OA) impacts hundreds of millions of people worldwide, with those affected incurring significant physical and financial burdens. Injuries such as focal defects to the articular surface are a major contributing risk factor for the development of OA. Current cartilage repair strategies are moderately effective at reducing pain but often replace damaged tissue with biomechanically inferior fibrocartilage. Here we describe the development, transcriptomic ontogenetic characterization and quality assessment at the single cell level, as well as the scaled manufacturing of an allogeneic human pluripotent stem cell-derived articular chondrocyte formulation that exhibits long-term functional repair of porcine articular cartilage. These results define a new potential clinical paradigm for articular cartilage repair and mitigation of the associated risk of OA.
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The modification of chromatin influences host transcriptional programs during bacterial infection, at times skewing the balance in favor of pathogen survival. To test the role of chromatin modifications during Mycobacterium tuberculosis infection, we analysed genome-wide deposition of H3K4me3 marks in macrophages infected with either avirulent M. tuberculosis H37Ra or virulent H37Rv, by chromatin immunoprecipitation, followed by sequencing. We validated differences in association of H3K4me3 at the loci of special AT-rich sequence binding protein 1 (SATB1) and dual specificity MAP kinase phosphatase 4 (DUSP4) between H37Rv and H37Ra-infected macrophages, and demonstrated their role in regulating bacterial survival in macrophages as well as the expression of chemokines. SATB1 repressed gp91phox (an NADPH oxidase subunit) thereby regulating reactive oxygen species (ROS) generation during infection. Long non-coding RNA HOX transcript antisense RNA (HOTAIR) was upregulated in H37Ra-, but downregulated in H37Rv-infected macrophages. HOTAIR overexpression correlated with deposition of repressive H3K27me3 marks around the TSSs of DUSP4 and SATB1, suggesting that its downregulation favors the transcription of SATB1 and DUSP4. In summary, we have delineated histone modification- and lncRNA-dependent mechanisms regulating gene expression patterns facilitating survival of virulent M. tuberculosis. Our observations raise the possibility of harnessing histone-modifying enzymes to develop host-directed therapies for tuberculosis.
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Fosfatasas de Especificidad Dual/metabolismo , Histonas/metabolismo , Macrófagos/metabolismo , Macrófagos/microbiología , Proteínas de Unión a la Región de Fijación a la Matriz/metabolismo , Fosfatasas de la Proteína Quinasa Activada por Mitógenos/metabolismo , Mycobacterium tuberculosis/patogenicidad , ARN Largo no Codificante/metabolismo , Quimiocinas/genética , Quimiocinas/metabolismo , Fosfatasas de Especificidad Dual/genética , Epigénesis Genética , Interacciones Huésped-Patógeno , Humanos , Macrófagos/inmunología , Proteínas de Unión a la Región de Fijación a la Matriz/genética , Metilación , Viabilidad Microbiana , Fosfatasas de la Proteína Quinasa Activada por Mitógenos/genética , Mycobacterium tuberculosis/inmunología , ARN Largo no Codificante/genética , Especies Reactivas de Oxígeno/metabolismo , Células THP-1 , VirulenciaRESUMEN
Naive and primed pluripotent states are very similar to each other, but subtle differences exist in their maintenance and differentiation programmes. Transcription factors (TFs) play a key role towards maintaining pluripotency and cellular reprogramming. However, TF expression dynamics and regulatory mechanisms in naive and primed pluripotent states are poorly understood. Here, we performed a comprehensive transcriptional analysis of both states, which revealed a gene expression pattern in mESCs (naive state) that appear to be distinct from mEpiSCs (primed state). We screened 10 TFs essential for maintenance, self-renewal and differentiation, of which the TFs- Notch3, Meis1, Gli3 and Srf can act as novel markers distinguishing the two states. Furthermore, a detailed bioinformatic analysis (involving these TFs) elucidated essential transcriptional circuits between the naive and primed pluripotent states.
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Regulación de la Expresión Génica , Células Madre Pluripotentes/fisiología , Factores de Transcripción/genética , Transcripción Genética , Animales , Diferenciación Celular , Células Cultivadas , Reprogramación Celular , Fibroblastos/citología , Fibroblastos/fisiología , Ratones , Células Madre Pluripotentes/citología , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
PIWI-interacting RNAs (piRNAs), â¼23-36 nucleotide-long small non-coding RNAs, earlier believed to be germline-specific, have now been identified in somatic cells including neural cells. However, piRNAs have not yet been studied in the human brain (HB) and Alzheimer's disease (AD)-affected brain. In this study, by next-generation small RNA sequencing, 564 and 451 piRNAs were identified in the HB and AD-affected brain respectively. The majority of the neuronal piRNAs have intronic origin wherein primary piRNAs are mostly from the negative strand. piRNAs originating from the coding sequence of mRNAs and tRNAs are highly conserved compared to other genomic contexts. We found 1923 mRNAs significantly down-regulated in AD as the predicted targets of 125 up-regulated piRNAs. The filtering of targets based on our criteria coupled with pathway enrichment analysis of all the predicted targets resulted in five most significant AD-associated pathways enriched with four genes (CYCS, LIN7C, KPNA6, and RAB11A) found to be regulated by four piRNAs. The qRT-PCR study verified the reciprocal expression of piRNAs and their targets. This study provides the first evidence of piRNAs in the HB and AD which will provide the foundation for future studies to unravel the regulatory role of piRNAs in the human brain and associated diseases. The sequencing data have been submitted to the GEO database (Accession no. GSE85075).
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Enfermedad de Alzheimer/genética , Regulación de la Expresión Génica , ARN Interferente Pequeño/genética , Estudios de Casos y Controles , Exones , Perfilación de la Expresión Génica , Genómica/métodos , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Intrones , Interferencia de ARN , ARN Mensajero/genética , ARN de Transferencia/genética , TranscriptomaRESUMEN
Early blight, caused by the fungus Alternaria solani, is a devastating foliar disease of tomatoes, causes massive yield loss each year worldwide. Molecular basis of the compatible host-pathogen interaction was elusive. We adopted next generation sequencing approach to decipher miRNAs and mRNAs that are differentially expressed during Alternaria-stress in tomato. Some of the interesting findings were also validated by alternative techniques. Our analysis revealed 181 known-miRNAs, belonging to 121 miRNA families, of which 67 miRNAs showed at least 2-fold change in expression level with the majority being downregulated. Concomitantly, 5,450 mRNAs were significantly regulated in the same diseased tissues. Differentially expressed genes were most significantly associated with response to stimulus process, photosynthesis, biosynthesis of secondary metabolites, plant-pathogen interaction and plant hormone signal transduction pathways. GO term enrichment-based categorization of gene-functions further supported this observation, as terms related to pathogen perception, disease signal transduction, cellular metabolic processes including oxidoreductase and kinase activity were over represented. In addition, we have discovered 102 miRNA-mRNA pairs which were regulated antagonistically, and careful study of the targeted mRNAs depicted that multiple transcription factors, nucleotide-binding site leucine-rich repeats, receptor-like proteins and enzymes related to cellular ROS management were profoundly affected. These studies have identified key regulators of Alternaria-stress response in tomato and the subset of genes that are likely to be post-transcriptionally silenced during the infection.
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Alternariosis/genética , MicroARNs , ARN Mensajero , Solanum lycopersicum/genética , Transcriptoma , Susceptibilidad a Enfermedades , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Secuenciación de Nucleótidos de Alto Rendimiento , Solanum lycopersicum/fisiología , Enfermedades de las Plantas/genética , ARN de PlantaRESUMEN
Chronic myelogenous leukemia (CML) is a myeloproliferative disorder characterized by increased proliferation or abnormal accumulation of granulocytic cell line without the depletion of their capacity to differentiate. A reciprocal chromosomal translocation proceeding to the 'Philadelphia chromosome', involving the ABL proto-oncogene and BCR gene residing on Chromosome 9 and 22 respectively, is observed to be attributed to CML pathogenesis. Recent studies have been unraveling the crucial role of genomic 'dark matter' or the non-coding repertoire in cancer initiation and progression. The intricate cross-talk between competitive endogenous RNAs (ceRNAs) provides a scaffold to systematically functionalize the miRNA response element harboring non-coding RNAs and incorporate them with the protein-coding RNA dimension in complex ceRNA networks. This network of coding and non-coding transcriptome linked by shared miRNAs evidently offers a platform to elucidate the complex regulatory interactions at the post-transcriptional level in human cancers. In this context, analyzing CML, from the perspective of the ceRNA hypothesis, surely craves intensive attention and a comprehensive discussion. Here, we performed RNA-seq data analysis to retrieve Lymphoblastoid and CML coding as well as non-coding repertoire and constructed a ceRNA network for the CML cell line, considering the non-cancer lymphoblastoid cell line as the control. We investigated if any alteration exists in the ceRNA landscape of the transcripts which are exhibiting differential expression across the two cell lines and observed that the major ceRNA regulators vary in cancer network when compared with the Lymphoblastoid network. The top ranked significant functional modules in the ceRNA network display cancer associated attributes and reveal putative regulators in CML pathogenesis.