45 research outputs found
Physiological Responses to Fe Deficiency in Split-Root Tomato Plants: Possible Roles of Auxin and Ethylene?
No full textIron (Fe) bioavailability in soils is often limited and can be further exacerbated by a non- homogeneous distribution in the soil profile, which has been demonstrated to vary both in space and time. Consequently, plants respond with morphological and physiological modifications at the root level involving a complex local and systemic signaling machinery. The present work unravels the role of two phytohormones (i.e., ethylene and auxin) and their integrated signaling in plant response to Fe deficiency. Inhibitors of auxin polar transport and of ethylene biosynthesis (N-1-naphthylphthalamic acid - NPA and aminoethoxyvinylglycine - AVG, respectively) were applied on tomato (Solanum lycopersicum L.) plants grown by the split-root technique, which allows to simulate condition of Fe heterogeneous distribution. Results showed that plants, exposed to an uneven Fe supply, triggered a complex auxin-ethylene signaling. A systemic action of auxin on FERRIC REDUCTASE OXIDASE 1 (SlFRO1) expression was revealed, while ethylene signaling was effective both locally and systemically. In addition, the investigation of Fe concentration in tissues showed that when leaves overcame Fe deficiency a Fe “steady state” was maintained. Therefore, physiological adaptation to this heterogeneous Fe supply could be mediated by the integration of the complex signaling pathways prompted by both auxin and ethylene activities
Isolation and functional characterization of a flavonoid transporter in roots of white lupin plants
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Ludwig: The physiologist
No full textThe thought reproduced in the above epigraph is taken from an article by Thurau et al. [1], who attribute it to Arthur Schopenhauer (17881860), an outstanding philosopher and author of the far-reaching piece Die Welt als Wille und Vorstellung (The World as Will and Representation). In German, it would perhaps read as etwas denken, das niemand vorher gedacht hat, während etwas sehen, was jeder sieht. We could not assert whether Schopenhauer really said that, but it should not be at all surprising if it were, because it sounds simple, perhaps even naïve, and very deep, indeed. It fits perfectly to Carl Friedrich Wilhelm Ludwigs personality (18161895), whom we will look at as physiologist in this second note. Yes, second notebecause in the first one [2], we looked at him as bioengineer. A third and last Retrospectroscope column completing this series will deal with his wonderful and always humble and generous activities as teacher. © 2012 IEEE.Fil: Valentinuzzi, Maximo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires; ArgentinaFil: Beneke, Klaus. Christin-Albrechts-University; AlemaniaFil: González, Germán Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; Argentin
Análisis espacial y percepción de los espacios públicos locales en los cantones de San José, Montes de Oca y Curridabat. Una contribución al diseño de políticas urbanas sostenibles desde la gestión ambiental
No full textUno de los problemas que caracteriza la gran expansión urbana a nivel mundial es la ausencia de planificación y ordenamiento territorial. La rápida urbanización se asocia directamente con la aglomeración, degradación ambiental y otros impedimentos a la productividad que intervienen en el bienestar humano, donde los espacios públicos locales, gracias a su importancia, se han convertido en factores de calidad de vida en las ciudades. Las áreas verdes en las ciudades tienen como objetivo generar una serie de beneficios sociales y ambientales que van más allá de un uso recreativo. Realizar un diagnóstico sobre Espacios Públicos Locales (en adelante EPL) enfocado en la distribución socio espacial; en los cantones de San José, Montes de Oca y Curridabat; en la percepción del usuario y servicios ecosistémicos brindados; en el distrito de San Pedro, es el objetivo de esta investigación. Al analizar la red de EPL de estos tres cantones, se puede definir que dichas áreas se distribuyen de manera agrupada, específicamente, en clúster de EPL con valores bajos en superficie. Las personas mayores a 50 años son el grupo que usa con mayor frecuencia los EPL analizados, donde el Parque El Retiro, uno de los EPL analizados, posee el mejor Índice de Importancia de Zonas Verdes, ubicándose en una zona donde el valor económico del suelo es alto; siendo que existe una correlación positiva entre las superficies de EPL y su ubicación con respecto al valor del terreno. Los habitantes de la zona de estudio no deberían de caminar más de 460 metros, que equivale aproximadamente a seis minutos a pie, a un EPL igual o mayor a 3200 m2. Se deberían crear políticas o incluir en los reglamentos existentes aspectos relevantes de los EPL, actualmente poco estudiados, tales como la distribución espacial, área de superficie, dispersión y grado de fragmentación.UCR::Vicerrectoría de Investigación::Sistema de Estudios de Posgrado::Interdisciplinarias::Maestría Académica en Gestión Ambiental y Ecoturism
Noninvasive DBS-Based Approaches to Assist Clinical Diagnosis and Treatment Monitoring of Gaucher Disease
No full textGaucher disease (GD) is an autosomal recessive inborn error of metabolism, belonging to the group of lysosomal storage diseases (LSDs). GD is caused by a defect in lysosomal glucocerebrosidase, responsible for glucosylceramide breakdown into glucose and ceramide. Because of this dysfunction, glucosylceramide progressively accumulates in the liver, spleen, bone marrow, bones, and in other tissues and organs, also causing anemia, hepatosplenomegaly, thrombocytopenia, and bone symptoms. Depending on neurological symptoms, GD is classified into three main types. Treatment options for LSDs, including enzyme replacement therapy, hematopoietic stem cell transplantation, small molecular weight pharmacologic chaperones, and, for some LSDs, gene therapy, are increasingly available. For this reason, many efforts are aimed at implementing newborn screening for LSDs since early detection accompanied by a prompt intervention has been demonstrated to be essential for reducing morbidity and mortality and for improved clinical outcomes. Herein, we report two siblings of preschool age, presenting with hepatosplenomegaly and thrombocytopenia. The initial suspicion of GD based on the clinical picture was further supported by biochemical confirmation, through newborn screening workflow, including first- and second-level testing on the same dried blood spot samples, and finally by molecular testing
Chronic Oleoylethanolamide Treatment Decreases Hepatic Triacylglycerol Level in Rat Liver by a PPARγ/SREBP-Mediated Suppression of Fatty Acid and Triacylglycerol Synthesis
No full textOleoylethanolamide (OEA) is a naturally occurring bioactive lipid belonging to the family of N-acylethanolamides. A variety of beneficial effects have been attributed to OEA, although the greater interest is due to its potential role in the treatment of obesity, fatty liver, and eating-related disorders. To better clarify the mechanism of the antiadipogenic effect of OEA in the liver, using a lipidomic study performed by 1H-NMR, LC-MS/MS and thin-layer chromatography analyses we evaluated the whole lipid composition of rat liver, following a two-week daily treatment of OEA (10 mg kg−1 i.p.). We found that OEA induced a significant reduction in hepatic triacylglycerol (TAG) content and significant changes in sphingolipid composition and ceramidase activity. We associated the antiadipogenic effect of OEA to decreased activity and expression of key enzymes involved in fatty acid and TAG syntheses, such as acetyl-CoA carboxylase, fatty acid synthase, diacylglycerol acyltransferase, and stearoyl-CoA desaturase 1. Moreover, we found that both SREBP-1 and PPARγ protein expression were significantly reduced in the liver of OEA-treated rats. Our findings add significant and important insights into the molecular mechanism of OEA on hepatic adipogenesis, and suggest a possible link between the OEA-induced changes in sphingolipid metabolism and suppression of hepatic TAG level
Common and specific responses to iron and phosphorus deficiencies in roots of apple tree (Malus × domestica)
No full textIron and phosphorus are abundant elements in soils but poorly available for plant nutrition. The availability of these two nutrients represents a major constraint for fruit tree cultivation such as apple (Malus × domestica) leading very often to a decrease of fruit productivity and quality worsening. Aim of this study was to characterize common and specific features of plant response to Fe and P deficiencies by ionomic, transcriptomic and exudation profiling of apple roots. Under P deficiency, the root release of oxalate and flavonoids increased. Genes encoding for transcription factors and transporters involved in the synthesis and release of root exudates were upregulated by P-deficient roots, as well as those directly related to P acquisition. In Fe-deficiency, plants showed an over-accumulation of P, Zn, Cu and Mn and induced the transcription of those genes involved in the mechanisms for the release of Fe-chelating compounds and Fe mobilization inside the plants. The intriguing modulation in roots of some transcription factors, might indicate that, in this condition, Fe homeostasis is regulated by a FIT-independent pathway. In the present work common and specific features of apple response to Fe and P deficiency has been reported. In particular, data indicate similar modulation of a. 230 genes, suggesting the occurrence of a crosstalk between the two nutritional responses involving the transcriptional regulation, shikimate pathway, and the root release of exudates
Circadian entrainment by light and host in the Chagas disease vector, Triatoma infestans
No full textTriatoma infestans (Reduviidae: Triatominae, "kissing bug") is the main insect vector of Trypanosoma cruzi, the causative agent of Chagas disease, a chronic trypanosomiasis infecting 10 million people world-wide. This hematophagous bug feeds on diurnal and nocturnal species during each host's quiescent time. As the hosts are also its major predators, kissing bugs are subjected to dual selective pressures from a single source. Therefore, synchronization of feeding with the host's behavior is critical to the insects' survival. We show that nonphotic signals linked to the host eclipse the role of light and dark as the primary circadian zeitgeber for these bugs, although light still strongly inhibits locomotor behavior directly. In nature, this combination provides the insect with great flexibility in organizing physiology and behavior: anticipating a quiescent host or avoiding its potential predation while remaining directly responsive to immediate environmental conditions. Manipulation of nonphotic entrainment could be a useful chronobiotic tool in the control of Chagas disease.Fil: Valentinuzzi, Verónica Sandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de Catamarca. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Secretaría de Industria y Minería. Servicio Geológico Minero Argentino. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Provincia de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja; ArgentinaFil: Amelotti, Ivana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de Catamarca. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Secretaría de Industria y Minería. Servicio Geológico Minero Argentino. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Provincia de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja; ArgentinaFil: Gorla, David Eladio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de Catamarca. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Secretaría de Industria y Minería. Servicio Geológico Minero Argentino. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Provincia de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja; ArgentinaFil: Catala, Silvia Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de Catamarca. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Secretaría de Industria y Minería. Servicio Geológico Minero Argentino. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Provincia de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja; ArgentinaFil: Ralph, Martin Roland. University of Toronto; Canad
Hsa-miR-200 and hsa-miR34 miRNA family members target cellular and viral genes regulating HCMV infection in head and neck paraganglioma
No full textParagangliomas (PGLs) are rare hypervascular tumours of the paraganglia, organelles connected with the autonomic branches of the cranial (head and neck) and thoraco-lumbar nerves (1). PGLs have a strong genetic basis, being frequently (~ 40%) associated with predisposing mutations in one of at least 15 nuclear genes (1), most relevantly SDHA/B/C/D, that encode the four subunits of succinate dehydrogenase (SDH), a mitochondrial enzyme participating in both oxidative phosphorylation and the Krebs cycle, and SDHAF2, required for SDHA flavination. However, the penetrance of these mutations is incomplete and genetically-modeled mice mutated in Sdhb, homolog of the human SDHB gene, do not develop any cancer. In 1971 an isolated report described the retrieval of an infectious virus, then identified as human cytomegalovirus (CMV) in a retroperitoneal PGL (2). This report was not followed-up, and only in the last decade HCMV has emerged as an oncomodulatory agent in neural-derived cancers and as a target of therapy in gliomas (3).
We show here evidence of a CMV-like herpesvirus, in high abundance, in head and neck PGLs. We collected over 100 HN-PGLs and examined them by electron microscopy, rapid in situ hybridation, IHC, IF and WB. All had mitochondrial changes, and all resulted positive for CMV-like viruses, regardless of SDH mutation status. We show here that the PGL-associated CMV-like viruses expresses viral proteins integrated in oncomodulatory pathways controlled by microRNAs of the miR200 and miR34 families.
We previously reported that the miR-200a,b,c and the miR34b,c are constitutively downregulated in PGLs (4), and that this results in upregulated expression of NOTCH1 (4), PDGFRA and ZEB1 (5) in PGL cells.
We enforced miR34s and miR200s overexpression by lentiviral reintroduction in PGL cells (PTJ64i) endogenously infected by the CMV-like PGL virus. This resulted in downregulation of IE2 (UL122), pp65 (UL83) and vMIA viral proteins, therefore affecting viral load. In the same cell system the IFN-inducible antiviral host protein viperin, encoded by the RSAD2 gene and highjacked by the CMV protein vMIA to deregulate mitochondrial metabolism by inhibition of fatty acids beta oxidation (6), was downregulated by reintroduction of miR34s, but not of miR200s.
We found that viperin, the most upregulated host protein induced by HCMV infection, is highly expressed in PGLs and derived cells together with its viral partner protein vMIA. This was consistent with evidence of lipogenesis and glycolysis in PGLs. The 3’UTR of RSAD2 is predicted to contain binding seed regions for the miR34s and the miR200s. Li et al. recently showed that the 3’UTR of RSAD2 is a direct target of miR200a and miR200b (7). We are verifying whether the 3’UTR of RSAD2 gene is direct target of the miR34s. We also show that in PGL cells treatment with the antiviral drug ganciclovir reduces viral load and significantly upregulates the miR200s and the miR34s levels. These results suggest that epigenetic deregulation of the miR-200s and of the miR-34s supports HCMV infection in PGLs and that infection by the CMV-like PGL viruses contributes to the metabolic phenotype of PGLs.
1) Pacak K, Wimalawansa SJ. Pheochromocytoma and paraganglioma. Endocr Pract 2015
2) Heine U, Ultrastructural and biological properties of a cytomegalovirus rescued from a human paraganglioma. Cancer Res. 1971.
3) Söderberg-Nauclér C et al., Cytomegalovirus in human brain tumors: Role in pathogenesis and potential treatment options. World J Exp Med. 2015.
4) Cama et al., Integrative genetic, epigenetic and pathological analysis of paraganglioma reveals complex dysregulation of NOTCH signaling. Acta Neuropatol. 2013
5) Verginelli F, et al. Paragangliomas arise through an autonomous vasculo-angio-neurogenic program inhibited by imatinib. Acta Neuropathol. 2018
6) Seo JY and Cresswell P. Viperin regulates cellular lipid metabolism during human cytomegalovirus infection. PLoS Pathog. 2013.
7) Li Z, et al. miR-200 family promotes podocyte differentiation through repression of RSAD2. Sci Rep. 201
