Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 67
Filtrar
Más filtros

Intervalo de año de publicación
1.
Cell Mol Life Sci ; 81(1): 313, 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39066826

RESUMEN

Bromodomain and extra-terminal (BET) proteins are relevant chromatin adaptors involved in the transcriptional control of thousands of genes. Two tandem N-terminal bromodomains are essential for chromatin attachment through acetyl-histone recognition. Recently, the BET proteins members BRD2 and BRD4 were found to interact with the SARS-CoV-2 envelope (E) protein, raising the question of whether the interaction constitutes a virus hijacking mechanism for transcription alteration in the host cell. To shed light on this question, we have compared the transcriptome of cells overexpressing E with that of cells treated with the BET inhibitor JQ1. Notably, E overexpression leads to a strong upregulation of natural immunity- and interferon response-related genes. However, BET inhibition results in the downregulation of most of these genes, indicating that these two conditions, far from causing a significant overlap of the altered transcriptomes, course with quite different outputs. Concerning the interaction of E protein with BET members, and differing from previous reports indicating that it occurs through BET bromodomains, we find that it relies on SEED and SEED-like domains, BET regions rich in Ser, Asp, and Glu residues. By taking advantage of this specific interaction, we have been able to direct selective degradation of E protein through a PROTAC system involving a dTAG-SEED fusion, highlighting the possible therapeutic use of this peptide for targeted degradation of a viral essential protein.


Asunto(s)
Proteínas de Ciclo Celular , SARS-CoV-2 , Factores de Transcripción , Triazoles , Humanos , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , SARS-CoV-2/metabolismo , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Triazoles/farmacología , Azepinas/farmacología , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/genética , Dominios Proteicos , Transcripción Genética/efectos de los fármacos , COVID-19/virología , COVID-19/metabolismo , Células HEK293 , Unión Proteica , Proteínas que Contienen Bromodominio
2.
Proc Natl Acad Sci U S A ; 119(52): e2210081119, 2022 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-36534808

RESUMEN

Carotenoids are isoprenoid lipids found across the tree of life with important implications in oxidative stress adaptations, photosynthetic metabolisms, as well as in membrane dynamics. The canonical view is that C40 carotenoids are synthesized from phytoene and C30 carotenoids from diapophytoene. Squalene is mostly associated with the biosynthesis of polycyclic triterpenes, although there have been suggestions that it could also be involved in the biosynthesis of C30 carotenoids. However, demonstration of the existence of this pathway in nature is lacking. Here, we demonstrate that C30 carotenoids are synthesized from squalene in the Planctomycetes bacteria and that this squalene route to C30 carotenoids is the most widespread in prokaryotes. Using the evolutionary history of carotenoid and squalene amino oxidases, we propose an evolutionary scenario to explain the origin and diversification of the different carotenoid and squalene-related pathways. We show that carotenoid biosynthetic pathways have been constantly transferred and neofunctionalized during prokaryotic evolution. One possible origin of the squalene pathway connects it with the one of C40 carotenoid synthesis of Cyanobacteria. The widespread occurrence of the squalene route to C30 carotenoids in Bacteria increases the functional repertoire of squalene, establishing it as a general hub of carotenoids and polycyclic triterpenes synthesis.


Asunto(s)
Cianobacterias , Triterpenos , Escualeno , Vías Biosintéticas , Carotenoides
3.
Nucleic Acids Res ; 50(17): 9838-9857, 2022 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-36124662

RESUMEN

High mobility group (HMG) proteins are chromatin regulators with essential functions in development, cell differentiation and cell proliferation. The protein HMG20A is predicted by the AlphaFold2 software to contain three distinct structural elements, which we have functionally characterized: i) an amino-terminal, intrinsically disordered domain with transactivation activity; ii) an HMG box with higher binding affinity for double-stranded, four-way-junction DNA than for linear DNA; and iii) a long coiled-coil domain. Our proteomic study followed by a deletion analysis and structural modeling demonstrates that HMG20A forms a complex with the histone reader PHF14, via the establishment of a two-stranded alpha-helical coiled-coil structure. siRNA-mediated knockdown of either PHF14 or HMG20A in MDA-MB-231 cells causes similar defects in cell migration, invasion and homotypic cell-cell adhesion ability, but neither affects proliferation. Transcriptomic analyses demonstrate that PHF14 and HMG20A share a large subset of targets. We show that the PHF14-HMG20A complex modulates the Hippo pathway through a direct interaction with the TEAD1 transcription factor. PHF14 or HMG20A deficiency increases epithelial markers, including E-cadherin and the epithelial master regulator TP63 and impaired normal TGFß-trigged epithelial-to-mesenchymal transition. Taken together, these data indicate that PHF14 and HMG20A cooperate in regulating several pathways involved in epithelial-mesenchymal plasticity.


Asunto(s)
Proteínas del Grupo de Alta Movilidad/metabolismo , Histonas , Proteínas Nucleares/metabolismo , Factores de Transcripción/metabolismo , Factor de Crecimiento Transformador beta , Cadherinas/genética , Cadherinas/metabolismo , Línea Celular Tumoral , Cromatina , Vía de Señalización Hippo , Histonas/metabolismo , Humanos , Proteómica , ARN Interferente Pequeño , Factores de Transcripción/genética , Factor de Crecimiento Transformador beta/genética
4.
J Public Health Manag Pract ; 30(1): 89-98, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37350621

RESUMEN

OBJECTIVE: To assess the impact of a multicomponent intervention in women with cervical dysplasia who were treated with loop electrosurgical excision procedure (LEEP), as well as the time between colposcopy and treatment. DESIGN: Retrospective cohort study. INTERVENTION: Clinic participation in a multicomponent cervical cancer prevention program that included community outreach, patient in-reach, and navigation, as well as provider capacity building with in-person training and ongoing telementoring through Project ECHO. MAIN OUTCOME MEASURES: Medical records were reviewed to evaluate women with cervical dysplasia undergoing treatment with LEEP within 90 days of colposcopy, as well as time between colposcopy and treatment. Baseline data from year 1 were compared with each subsequent year of implementation. Additional variables examined included patient's age, history of abnormal screening results, and percentage of families living below poverty line based on county of residence, parity, and clinic site. We performed logistic regression and multiple linear regression analyses to assess the programmatic impact in the outcomes of interest by year of program implementation. RESULTS: A total of 290 women were included in the study. The proportion of women undergoing treatment within 90 days of colposcopy increased from 76.2% at baseline to 91.3% in year 3 and 92.9% in year 4 of program implementation. The odds of undergoing treatment within 90 days were 5.11 times higher in year 4 of program implementation than at baseline. The mean time between colposcopy and LEEP decreased from 62 days at baseline to 45 days by year 4 of program implementation. CONCLUSIONS: Implementation of our multicomponent cervical cancer prevention program increased the proportion of women undergoing LEEP within 90 days of colposcopy and decreased the time between colposcopy and LEEP. This program has the potential to support cervical cancer prevention efforts and could be implemented in other low-resource settings.


Asunto(s)
Lesiones Precancerosas , Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Embarazo , Femenino , Humanos , Neoplasias del Cuello Uterino/cirugía , Neoplasias del Cuello Uterino/diagnóstico , Estudios Retrospectivos , Texas/epidemiología , Electrocirugia/métodos , Displasia del Cuello del Útero/patología , Displasia del Cuello del Útero/cirugía , Lesiones Precancerosas/cirugía
5.
Int Ophthalmol ; 43(8): 2731-2736, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37185774

RESUMEN

PURPOSE: To analyze using Pentacam®, the corneal and anterior chamber changes following periocular botulinum toxin injection in patients with facial dystonia. METHODS: Prospective study that included patients with facial dystonia that were going to receive a periocular botulinum toxin injection for the first time or six months or more after the previous injection. A Pentacam® examination was carried out in all patients before and 4 weeks after the injection. RESULTS: Thirty-one eyes were included. Twenty-two had a diagnosis of blepharospasm and nine of hemifacial spasm. Analysis of corneal and anterior chamber parameters revealed a significant decrease in iridocorneal angle after botulinum toxin injection (from 35 ± 10º to 33.8 ± 9.7º, p = 0.022). No other corneal or anterior chamber parameters changed significantly after the injection. CONCLUSIONS: Periocular botulinum toxin injection causes narrowing of the iridocorneal angle.


Asunto(s)
Blefaroespasmo , Toxinas Botulínicas Tipo A , Toxinas Botulínicas , Distonía , Espasmo Hemifacial , Humanos , Blefaroespasmo/tratamiento farmacológico , Toxinas Botulínicas/efectos adversos , Espasmo Hemifacial/tratamiento farmacológico , Estudios Prospectivos , Distonía/tratamiento farmacológico , Cámara Anterior , Inyecciones Intraoculares , Toxinas Botulínicas Tipo A/efectos adversos
6.
Mol Biol Evol ; 37(7): 1925-1941, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32125435

RESUMEN

Polycyclic triterpenes are members of the terpene family produced by the cyclization of squalene. The most representative polycyclic triterpenes are hopanoids and sterols, the former are mostly found in bacteria, whereas the latter are largely limited to eukaryotes, albeit with a growing number of bacterial exceptions. Given their important role and omnipresence in most eukaryotes, contrasting with their scant representation in bacteria, sterol biosynthesis was long thought to be a eukaryotic innovation. Thus, their presence in some bacteria was deemed to be the result of lateral gene transfer from eukaryotes. Elucidating the origin and evolution of the polycyclic triterpene synthetic pathways is important to understand the role of these compounds in eukaryogenesis and their geobiological value as biomarkers in fossil records. Here, we have revisited the phylogenies of the main enzymes involved in triterpene synthesis, performing gene neighborhood analysis and phylogenetic profiling. Squalene can be biosynthesized by two different pathways containing the HpnCDE or Sqs proteins. Our results suggest that the HpnCDE enzymes are derived from carotenoid biosynthesis ones and that they assembled in an ancestral squalene pathway in bacteria, while remaining metabolically versatile. Conversely, the Sqs enzyme is prone to be involved in lateral gene transfer, and its emergence is possibly related to the specialization of squalene biosynthesis. The biosynthesis of hopanoids seems to be ancestral in the Bacteria domain. Moreover, no triterpene cyclases are found in Archaea, invoking a potential scenario in which eukaryotic genes for sterol biosynthesis assembled from ancestral bacterial contributions in early eukaryotic lineages.


Asunto(s)
Carotenoides/metabolismo , Evolución Molecular , Farnesil Difosfato Farnesil Transferasa/genética , Filogenia , Escualeno/metabolismo , Eucariontes/metabolismo , Farnesil Difosfato Farnesil Transferasa/metabolismo , Genes Bacterianos , Esteroles/biosíntesis
7.
Thorax ; 75(9): 754-763, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32709610

RESUMEN

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive lung disease which presents a grave prognosis for diagnosed patients. Nintedanib (a triple tyrosine kinase inhibitor) and pirfenidone (unclear mechanism of action) are the only approved therapies for IPF, but have limited efficacy. The pathogenic mechanisms of this disease are not fully elucidated; however, a role for mast cells (MCs) has been postulated. OBJECTIVES: The aim of this work was to investigate a role for MCs in IPF and to understand whether nintedanib or pirfenidone could impact MC function. METHODS AND RESULTS: MCs were significantly elevated in human IPF lung and negatively correlated with baseline lung function (FVC). Importantly, MCs were positively associated with the number of fibroblast foci, which has been linked to increased mortality. Furthermore, MCs were increased in the region immediately surrounding the fibroblast foci, and co-culture studies confirmed a role for MC-fibroblast crosstalk in fibrosis. Nintedanib but not pirfenidone inhibited recombinant stem cell factor (SCF)-induced MC survival. Further evaluation of nintedanib determined that it also inhibited human fibroblast-mediated MC survival. This was likely via a direct effect on ckit (SCF receptor) since nintedanib blocked SCF-stimulated ckit phosphorylation, as well as downstream effects on MC proliferation and cytokine release. In addition, nintedanib ablated the increase in lung MCs and impacted high tissue density frequency (HDFm) in a rat bleomycin model of lung fibrosis. CONCLUSION: Nintedanib inhibits MC survival and activation and thus provides a novel additional mechanism by which this drug may exert anti-fibrotic effects in patients with IPF.


Asunto(s)
Supervivencia Celular/efectos de los fármacos , Fibroblastos/fisiología , Fibrosis Pulmonar Idiopática/patología , Indoles/farmacología , Mastocitos/fisiología , Inhibidores de Proteínas Quinasas/farmacología , Anciano , Animales , Antiinflamatorios no Esteroideos/farmacología , Bleomicina , Proliferación Celular/efectos de los fármacos , Quimiocina CCL2/metabolismo , Técnicas de Cocultivo , Modelos Animales de Enfermedad , Femenino , Fibroblastos/patología , Fibrosis , Humanos , Fibrosis Pulmonar Idiopática/tratamiento farmacológico , Fibrosis Pulmonar Idiopática/fisiopatología , Pulmón/patología , Masculino , Mastocitos/patología , Persona de Mediana Edad , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-kit/metabolismo , Piridonas/farmacología , Ratas , Proteínas Recombinantes/farmacología , Transducción de Señal/efectos de los fármacos , Factor de Células Madre/farmacología , Capacidad Vital
9.
Antonie Van Leeuwenhoek ; 113(12): 1915-1926, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32583191

RESUMEN

Access to axenic cultures is crucial to extend the knowledge of the biology, lifestyle or metabolic capabilities of bacteria from different phyla. The phylum Planctomycetes is an excellent example since its members display an unusual cell biology and complex lifestyles. As a contribution to the current collection of axenic planctomycete cultures, here we describe strain Mal48T isolated from phytoplankton material sampled at the coast of S'Arenal close to Palma de Mallorca (Spain). The isolated strain shows optimal growth at pH 7.0-7.5 and 30 °C and exhibits typical features of Planctomycetes. Cells of the strain are spherical to pear-shaped, divide by polar budding with daughter cells showing the same shape as the mother cell, tend to aggregate, display a stalk and produce matrix or fimbriae. Strain Mal48T showed 95.8% 16S rRNA gene sequence similarity with the recently described Thalassoglobus neptunius KOR42T. The genome sequence of the novel isolate has a size of 6,357,355 bp with a G+C content of 50.3%. A total of 4874 protein-coding genes, 41 tRNA genes and 2 copies of the 16S rRNA gene are encoded in the genome. Based on phylogenetic, morphological and physiological analyses, we conclude that strain Mal48T (= DSM 100737T = LMG 29019T) should be classified as the type strain of a new species in the genus Thalassoglobus, for which the name Thalassoglobus polymorphus sp. nov. is proposed.


Asunto(s)
Ácidos Grasos , ADN Bacteriano/genética , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , España
10.
Antonie Van Leeuwenhoek ; 113(12): 1901-1913, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32583192

RESUMEN

Planctomycetes are ubiquitous bacteria with environmental and biotechnological relevance. Axenic cultures of planctomycetal strains are the basis to analyse their unusual biology and largely uncharacterised metabolism in more detail. Here, we describe strain Mal4T isolated from marine sediments close to Palma de Mallorca, Spain. Strain Mal4T displays common planctomycetal features, such as division by polar budding and the presence of fimbriae and crateriform structures on the cell surface. Cell growth was observed at ranges of 10-39 °C (optimum at 31 °C) and pH 6.5-9.0 (optimum at 7.5). The novel strain shows as pear-shaped cells of 2.0 ± 0.2 × 1.4 ± 0.1 µm and is one of the rare examples of orange colony-forming Planctomycetes. Its genome has a size of 7.7 Mb with a G+C content of 63.4%. Phylogenetically, we conclude that strain Mal4T (= DSM 100296T = LMG 29133T) is the type strain representing the type species of a novel genus, for which we propose the name Maioricimonas rarisocia gen. nov., sp. nov.


Asunto(s)
Ácidos Grasos , Sedimentos Geológicos , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Ácidos Grasos/análisis , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , España
11.
Plant Cell ; 27(9): 2560-81, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26342016

RESUMEN

Prior to the release of their cargoes into the vacuolar lumen, sorting endosomes mature into multivesicular bodies (MVBs) through the action of ENDOSOMAL COMPLEX REQUIRED FOR TRANSPORT (ESCRT) protein complexes. MVB-mediated sorting of high-affinity phosphate transporters (PHT1) to the vacuole limits their plasma membrane levels under phosphate-sufficient conditions, a process that allows plants to maintain phosphate homeostasis. Here, we describe ALIX, a cytosolic protein that associates with MVB by interacting with ESCRT-III subunit SNF7 and mediates PHT1;1 trafficking to the vacuole in Arabidopsis thaliana. We show that the partial loss-of-function mutant alix-1 displays reduced vacuolar degradation of PHT1;1. ALIX derivatives containing the alix-1 mutation showed reduced interaction with SNF7, providing a simple molecular explanation for impaired cargo trafficking in alix-1 mutants. In fact, the alix-1 mutation also hampered vacuolar sorting of the brassinosteroid receptor BRI1. We also show that alix-1 displays altered vacuole morphogenesis, implying a new role for ALIX proteins in vacuolar biogenesis, likely acting as part of ESCRT-III complexes. In line with a presumed broad target spectrum, the alix-1 mutation is pleiotropic, leading to reduced plant growth and late flowering, with stronger alix mutations being lethal, indicating that ALIX participates in diverse processes in plants essential for their life.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas Portadoras/metabolismo , Proteínas de Transporte de Fosfato/metabolismo , Fosfatos/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas Portadoras/genética , Citosol/metabolismo , Complejos de Clasificación Endosomal Requeridos para el Transporte/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas Fluorescentes Verdes/genética , Homeostasis , Mutación , Proteínas de Transporte de Fosfato/genética , Plantas Modificadas Genéticamente , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo , Multimerización de Proteína , Transporte de Proteínas , Vacuolas/genética , Vacuolas/metabolismo
13.
Antonie Van Leeuwenhoek ; 111(6): 785-799, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29058138

RESUMEN

These are exciting times for PVC researchers! The PVC superphylum is composed of the bacterial phyla Planctomycetes, Verrucomicrobia, Chlamydiae (those three founders giving it its name), Lentisphaerae and Kirimatiellaeota as well as some uncultured candidate phyla, such as the Candidatus Omnitrophica (previously known as OP3). Despite early debates, most of the disagreements that surround this group of bacteria have been recently resolved. In this article, we review the history of the study of PVC bacteria, with a particular focus on the misinterpretations that emerged early in the field and their resolution. We begin with a historical perspective that describes the relevant facts of PVC research from the early times when they were not yet termed PVC. Those were controversial times and we refer to them as the "discovery age" of the field. We continue by describing new discoveries due to novel techniques and data that combined with the reinterpretations of old ones have contributed to solve most of the discordances and we refer to these times as the "illumination age" of PVC research. We follow by arguing that we are just entering the "golden age" of PVC research and that the future of this growing community is looking bright. We finish by suggesting a few of the directions that PVC researches might take in the future.


Asunto(s)
Chlamydiaceae/genética , Evolución Molecular , Planctomycetales/genética , Bacterias Anaerobias/genética , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , ARN Ribosómico 16S/genética , Verrucomicrobia/genética
14.
Plant Physiol ; 167(4): 1511-26, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25670816

RESUMEN

Arabidopsis (Arabidopsis thaliana) absorbs inorganic phosphate (Pi) from the soil through an active transport process mediated by the nine members of the PHOSPHATE TRANSPORTER1 (PHT1) family. These proteins share a high level of similarity (greater than 61%), with overlapping expression patterns. The resulting genetic and functional redundancy prevents the analysis of their specific roles. To overcome this difficulty, our approach combined several mutations with gene silencing to inactivate multiple members of the PHT1 family, including a cluster of genes localized on chromosome 5 (PHT1;1, PHT1;2, and PHT1;3). Physiological analyses of these lines established that these three genes, along with PHT1;4, are the main contributors to Pi uptake. Furthermore, PHT1;1 plays an important role in translocation from roots to leaves in high phosphate conditions. These genetic tools also revealed that some PHT1 transporters likely exhibit a dual affinity for phosphate, suggesting that their activity is posttranslationally controlled. These lines display significant phosphate deficiency-related phenotypes (e.g. biomass and yield) due to a massive (80%-96%) reduction in phosphate uptake activities. These defects limited the amount of internal Pi pool, inducing compensatory mechanisms triggered by the systemic Pi starvation response. Such reactions have been uncoupled from PHT1 activity, suggesting that systemic Pi sensing is most probably acting downstream of PHT1.


Asunto(s)
Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas , Familia de Multigenes , Proteínas de Transporte de Fosfato/metabolismo , Fosfatos/metabolismo , Transducción de Señal , Arabidopsis/fisiología , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Transporte Biológico , Mutación , Proteínas de Transporte de Fosfato/genética , Raíces de Plantas/metabolismo , Plantas Modificadas Genéticamente
15.
Plant Cell ; 23(11): 3992-4012, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22128124

RESUMEN

Compartmentation of the eukaryotic cell requires a complex set of subcellular messages, including multiple retrograde signals from the chloroplast and mitochondria to the nucleus, to regulate gene expression. Here, we propose that one such signal is a phosphonucleotide (3'-phosphoadenosine 5'-phosphate [PAP]), which accumulates in Arabidopsis thaliana in response to drought and high light (HL) stress and that the enzyme SAL1 regulates its levels by dephosphorylating PAP to AMP. SAL1 accumulates in chloroplasts and mitochondria but not in the cytosol. sal1 mutants accumulate 20-fold more PAP without a marked change in inositol phosphate levels, demonstrating that PAP is a primary in vivo substrate. Significantly, transgenic targeting of SAL1 to either the nucleus or chloroplast of sal1 mutants lowers the total PAP levels and expression of the HL-inducible ASCORBATE PEROXIDASE2 gene. This indicates that PAP must be able to move between cellular compartments. The mode of action for PAP could be inhibition of 5' to 3' exoribonucleases (XRNs), as SAL1 and the nuclear XRNs modulate the expression of a similar subset of HL and drought-inducible genes, sal1 mutants accumulate XRN substrates, and PAP can inhibit yeast (Saccharomyces cerevisiae) XRNs. We propose a SAL1-PAP retrograde pathway that can alter nuclear gene expression during HL and drought stress.


Asunto(s)
Adenosina Difosfato/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Cloroplastos/metabolismo , Nucleotidasas/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Ascorbato Peroxidasas/genética , Ascorbato Peroxidasas/metabolismo , Núcleo Celular/genética , Sequías , Exorribonucleasas/genética , Exorribonucleasas/metabolismo , Regulación de la Expresión Génica de las Plantas , Luz , Mitocondrias/metabolismo , Mutación , Nucleotidasas/genética , Monoéster Fosfórico Hidrolasas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Transducción de Señal
16.
Materials (Basel) ; 17(4)2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38399098

RESUMEN

This paper presents the preparation of heterogeneous catalysts for the direct hydrogenation process of CO2 to methanol. The development of the modern chemical industry is inextricably linked to the use of catalytic processes. As a result, currently over 80% of new technologies introduced in the chemical industry incorporate catalytic processes. Since the basic factor of catalytic processes is the catalysts, the studies for the deepening of the knowledge regarding the nature of the action of the catalysts, for the development of new catalysts and catalytic systems, as well as for their improvement, represent a research priority of a fundamental or applied nature. The Cu/ZnO/Al2O3 catalyst for the synthesis of green methanol, using precursors of an inorganic (copper nitrate, denoted by Cu/ZnO/Al2O3-1) and organic (copper acetate, denoted by Cu/ZnO/Al2O3-2) nature, are obtained by chemical impregnation that includes two stages: preparation and one of calcination. The preparation methods and conditions, as well as the physico-chemical properties of the catalyst precursor, play a major role in the behavior of the catalysts. The prepared catalysts were characterized using atomic adsorption analysis, scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis, specific surface area and pore size analyses, adsorption, and the chemisorption of vapor (BET).

17.
Kidney Int Rep ; 9(6): 1876-1891, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38899206

RESUMEN

Introduction: Inflammation is a significant contributor to cardiorenal morbidity and mortality in diabetic kidney disease (DKD). The pathophysiological mechanisms linking systemic, subacute inflammation and local, kidney injury-initiated immune maladaptation is partially understood. Methods: Here, we explored the expression of proinflammatory cytokines in patients with DKD; investigated mouse models of type 1 and type 2 diabetes (T2D); evaluated glomerular signaling in vitro; performed post hoc analyses of systemic and urinary markers of inflammation; and initiated a phase 2b clinical study (FRONTIER-1; NCT04170543). Results: Transcriptomic profiling of kidney biopsies from patients with DKD revealed significant glomerular upregulation of interleukin-33 (IL-33). Inhibition of IL-33 signaling reduced glomerular damage and albuminuria in the uninephrectomized db/db mouse model (T2D/DKD). On a cellular level, inhibiting IL-33 improved glomerular endothelial health by decreasing cellular inflammation and reducing release of proinflammatory cytokines. Therefore, FRONTIER-1 was designed to test the safety and efficacy of the IL-33-targeted monoclonal antibody tozorakimab in patients with DKD. So far, 578 patients are enrolled in FRONTIER-1. The baseline inflammation status of participants (N > 146) was assessed in blood and urine. Comparison to independent reference cohorts (N > 200) validated the distribution of urinary tumor necrosis factor receptor 1 (TNFR1) and C-C motif chemokine ligand 2 (CCL2). Treatment with dapagliflozin for 6 weeks did not alter these biomarkers significantly. Conclusion: We show that blocking the IL-33 pathway may mitigate glomerular endothelial inflammation in DKD. The findings from the FRONTIER-1 study will provide valuable insights into the therapeutic potential of IL-33 inhibition in DKD.

18.
Cell Rep ; 43(3): 113855, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38427563

RESUMEN

SWI/SNF complexes are evolutionarily conserved, ATP-dependent chromatin remodeling machines. Here, we characterize the features of SWI/SNF-dependent genes using BRM014, an inhibitor of the ATPase activity of the complexes. We find that SWI/SNF activity is required to maintain chromatin accessibility and nucleosome occupancy for most enhancers but not for most promoters. SWI/SNF activity is needed for expression of genes with low to medium levels of expression that have promoters with (1) low chromatin accessibility, (2) low levels of active histone marks, (3) high H3K4me1/H3K4me3 ratio, (4) low nucleosomal phasing, and (5) enrichment in TATA-box motifs. These promoters are mostly occupied by the canonical Brahma-related gene 1/Brahma-associated factor (BAF) complex. These genes are surrounded by SWI/SNF-dependent enhancers and mainly encode signal transduction, developmental, and cell identity genes (with almost no housekeeping genes). Machine-learning models trained with different chromatin characteristics of promoters and their surrounding regulatory regions indicate that the chromatin landscape is a determinant for establishing SWI/SNF dependency.


Asunto(s)
Cromatina , Factores de Transcripción , Cromatina/genética , Factores de Transcripción/metabolismo , Nucleosomas/genética , Ensamble y Desensamble de Cromatina
19.
Plant Cell ; 22(4): 1104-17, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20363771

RESUMEN

Plants adapt to different environmental conditions by constantly forming new organs in response to morphogenetic signals. Lateral roots branch from the main root in response to local auxin maxima. How a local auxin maximum translates into a robust pattern of gene activation ensuring the proper growth of the newly formed lateral root is largely unknown. Here, we demonstrate that miR390, TAS3-derived trans-acting short-interfering RNAs (tasiRNAs), and AUXIN RESPONSE FACTORS (ARFs) form an auxin-responsive regulatory network controlling lateral root growth. Spatial expression analysis using reporter gene fusions, tasi/miRNA sensors, and mutant analysis showed that miR390 is specifically expressed at the sites of lateral root initiation where it triggers the biogenesis of tasiRNAs. These tasiRNAs inhibit ARF2, ARF3, and ARF4, thus releasing repression of lateral root growth. In addition, ARF2, ARF3, and ARF4 affect auxin-induced miR390 accumulation. Positive and negative feedback regulation of miR390 by ARF2, ARF3, and ARF4 thus ensures the proper definition of the miR390 expression pattern. This regulatory network maintains ARF expression in a concentration range optimal for specifying the timing of lateral root growth, a function similar to its activity during leaf development. These results also show how small regulatory RNAs integrate with auxin signaling to quantitatively regulate organ growth during development.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , MicroARNs/genética , Raíces de Plantas/crecimiento & desarrollo , ARN Interferente Pequeño/genética , Factores de Transcripción/metabolismo , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/genética , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Redes Reguladoras de Genes , Genes Reporteros , Ácidos Indolacéticos/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , ARN de Planta/genética , Factores de Transcripción/genética
20.
Nat Commun ; 14(1): 7224, 2023 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-37940686

RESUMEN

Planctopirus limnophila belongs to the bacterial phylum Planctomycetes, a relatively understudied lineage with remarkable cell biology features. Here, we report a genome-wide analysis of essential gene content in P. limnophila. We show that certain genes involved in peptidoglycan synthesis or cell division, which are essential in most other studied bacteria, are not essential for growth under laboratory conditions in this species. We identify essential genes likely involved in lipopolysaccharide biosynthesis, consistent with the view of Planctomycetes as diderm bacteria, and highlight other essential genes of unknown functions. Furthermore, we explore potential stages of evolution of the essential gene repertoire in Planctomycetes and the related phyla Verrucomicrobia and Chlamydiae. Our results provide insights into the divergent molecular and cellular biology of Planctomycetes.


Asunto(s)
Genes Esenciales , Planctomycetales , Planctomycetales/genética , Verrucomicrobia/genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA