Exploración de la interacción entre la región 5´UTR del Sugarcane Mosaic Virus (SCMV) y proteínas del hospedero maíz

  Antecedentes: El virus del mosaico de la caña de azúcar, SCMV (Potyviridae) es un miembro de la gran familia de virus de ARN de cadena positiva, sin una estructura CAP en su extremo 5´no traducido (5`UTR), pero con una proteína viral unida al genoma (VPg) y una cola poli A en su extremo 3´UTR. Se ha sugerido que proteínas del hospedero hacen un puente entre las regiones no traducidas virales 5´y 3´ para potenciar la traducción viral. Dado que las regiones no traducidas presentes en los genomas virales contienen elementos involucrados en la regulación de su ciclo replicativo, es importante analizar la interacción entre estas regiones y las proteínas virales o del hospedero para inferir su función. Objetivo: Determinar si existen proteínas del hospedero maíz que pudieran estar interactuando con la región 5´UTR de SCMV. Metodología: La región 5´UTR de SCMV se amplificó por PCR incluyendo la secuencia del promotor T7 en la secuencia del oligo 5´ UTR y se generaron sus transcritos marcados radiactivamente. Los transcritos marcados fueron entrecruzados con extractos proteicos de hojas de maíz sanas e infectadas. Resultados: Los resultados sugieren la presencia de una proteína putativa de interacción del hospedante maíz de aproximadamente 53kDa, con la región 5´UTR de SCMV. Conclusión: Los ensayos de entrecruzamiento, especificidad y estabilidad de los complejos ARN-proteína sugieren que en el hospedante maíz existe al menos una proteína que interactúa con la región 5´ UTR de SCMV.Palabras Clave: Complejo ARN-proteína, entrecruzamiento UV, fracción proteica, Potyvirus, VPg. Abstract Background: Sugarcane mosaic virus is a member of the great family of positive sense RNA viruses, without a CAP structure in its 5´UTR end, but with a viral protein attached to the genome (VPg) and a poli A tail in its 3´UTR end. It has been suggested that some host proteins make a bridge between the untranslated 5´and 3´ regions (UTRs) to enhance the canonical and/or non-canonical virus translation. Since the UTR regions present in the viral genomes have some elements involved in the regulation of their replicative cycle, it is important to analyze the interaction that may occur between these regions and the viral or host proteins to infer regarding its function. Objective: To identify proteins of the host maize that could be interacting with the 5´UTR region of SCMV. Methodology: 5´UTR region of SCMV was amplified by PCR including the sequence of the T7 promoter in the 5´oligo sequence. The transcripts were radioactively labeled. Labeled transcripts were crosslinked with proteins extracts from healthy and infected maize leaves. Results: The results suggest the presence of a 53 kDa putative protein interacting with the 5 ´UTR region of SCMV. Conclusion: Crosslinking essays, specificity and the stability of the RNA-protein complex suggest that in maize host there is at least one protein that interacts with the 5´UTR region of SCMV.Keywords: RNA-Protein complex, UV crosslinking, protein fraction, Potyvirus, VPg. ResumoAntecedentes: O vírus do mosaico da cana de açúcar (SCMV) da Família Potyviridae é um membro da grande família de vírus de ARN de cadeia positiva, sem uma estrutura CAP em seu extremo 5´ não traduzido (5`UTR), mas com uma proteína viral unida ao genoma (VPg) e uma cola poli A em seu extremo 3´UTR. Tem-se sugerido que proteínas do hospedeiro fazem uma ponte entre as regiões não traduzidas virales 5´e 3´ para potenciar a tradução viral. Devido que as regiões não traduzidas presentes nos genomas virais contém elementos involucrados na regulação de seu ciclo replicativo, é importante analisar a interação entre estas regiões e as proteínas virales O do hospedeiro para inferir sua função. Objetivo: Determinar se existem proteínas hospedeiras milho que puderam estar interatuando com a região 5´UTR de SCMV. Metodologia: A região 5´UTR de SCMV se amplificou por PCR incluindo a sequência do promotor T7 na sequência do oligo 5´ UTR e se geraram seus transcritos marcados radiativamente. Os transcritos marcados foram entrecruzados com extratos proteicos de folhas de milho saudáveis e infetadas. Resultados: Os resultados sugerem a presença de uma proteína putativa de interação do hospedeiro milho de aproximadamente 53 kDa, com a região 5´UTR de SCMV. Conclusão: Os ensaios de entrecruzamento, especificidade e estabilidade dos complexos ARN proteía sugerem que no hospedeiro milho existe pelo menos uma proteína que interatua com a região 5´ UTR de SCMV.Palavras-chave: complexo ARN-proteína, entrecruzamento UV, fracção proteica, Potyvirus, VPg

Short distance movement of genomic negative strands in a host and nonhost for Sugarcane mosaic virus (SCMV)

<p>Abstract</p> <p>Background</p> <p>In order to obtain an initial and preliminary understanding of host and nonhost resistance in the initial step of potyvirus replication, both positive and negative <it>Sugarcane mosaic virus </it>(SCMV) strands where traced in inoculated and systemic leaves in host and nonhost resistant maize and sugarcane for one Mexican potyviral isolate (SCMV-VER1). Intermediary replication forms, such as the negative viral strand, seem to only move a short distance as surveyed by RT-PCR analysis and ELISA in different leaves. Virus purification was also done in leaves and stems.</p> <p>Results</p> <p>Susceptible maize plants allowed for viral SCMV replication, cell-to-cell, and long distance movement, as indicated by the presence of the coat protein along the plant. In the host resistant maize plants for the SCMV-VER1 isolate, the virus was able to establish the disease though the initial steps of virus replication, as detected by the presence of negative strands, in the basal area of the inoculated leaves at six and twelve days post inoculation. The nonhost sugarcane for SCMV-VER1 and the host sugarcane for SCMV-CAM6 also allowed the initial steps of viral replication for the VER1 isolate in the local inoculated leaf. SCMV-VER1 virions could be extracted from stems of susceptible maize with higher titers than leaves.</p> <p>Conclusion</p> <p>Nonhost and host resistance allow the initial steps of potyvirus SCMV replication, as shown by the negative strands' presence. Furthermore, both hosts allow the negative viral strands' local movement, but not their systemic spread through the stem. The presence of larger amounts of extractable virions from the stem (as compared to the leaves) in susceptible maize lines suggests their long distance movement as assembled particles. This will be the first report suggesting the long distance movement of a monocot potyvirus as a virion.</p

Identificación de la aplicación de políticas públicas de educación inclusiva en la institución educativa sagrado corazón de jesús colombia entre los años 2017 a 2019

Entrevistas y cronogramasEl siguiente trabajo de investigación se realizará en la Institución Educativa Sagrado Corazón de Jesús, municipio de Turbo, cuyo objeto es identificar aplicación de políticas públicas de Educación Inclusiva que se desarrollaron entre los años 2017 y 2019, con el fin de generar propuestas participativas de intervención educativa que brinde a los docentes del establecimientos pautas y sugerencias para atender población con capacidades educativas especiales y dar cumplimiento con las políticas pública que respalda la educación inclusiva en el país.The following research work will be carried out at the Sagrado Corazón de Jesús Educational Institution, Turbo municipality, whose objective is to identify the application of inclusive education public policies that were developed between 2017 and 2019, in order to generate participatory intervention proposals program that provides the teachers of the establishments with guidelines and suggestions to serve the population with special educational capacities and comply with public policies that support inclusive education in the country

Marcadores rapd para la identificación del sexo en papaya (carica papaya l.) en colombia

La determinación del sexo en plantas de papaya es considerado un sistema intrigante, debido a que esta especie presenta tres sexos (macho, hembra y hermafrodita) determinados por un locus multialélico. Además, esta especie no presenta cromosomas sexuales morfológicamente diferenciables. Los marcadores moleculares pueden asociarse a características de interés, como en el presente caso, al sexo en plántulas de papaya. Con el objetivo de identificar marcadores moleculares que permitan una rápida identificación del sexo en genotipos colombianos de plántulas de papaya, se aplicó la técnica RAPD (ampliación aleatoria de polimorfismos del ADN). El estudio encontró tres marcadores RAPD polimórficos, los cuales permitieron diferenciar los sexos de la papaya. Dos marcadores fueron específicos para plantas macho y hermafrodita, y un tercero para plantas hembra. Estos nuevos marcadores moleculares podrán ser beneficiosos en la determinación del sexo en genotipos colombianos de papaya

Efecto de la aplicación de agroquímicos en un cultivo de arroz sobre los microorganismos del suelo

En un Oxisol de los Llanos Orientales de Colombia, en condiciones de campo se evaluó el efecto de la aplicación de agroquímicos sobre los microorganismos presentes en un cultivo de arroz secano. Los agroquímicos evaluados fueron Glifosato, Bispiribac, Azoxystrobin y Malatión, aplicados en dosis comerciales, en un diseño experimental de bloques con medidas repetidas. Para el recuento de microorganismos se tomaron muestras compuestas de suelo rizosférico usando la metodología de transectos. A partir de las muestras fueron realizados conteos microbianos empleando dilución en placa y los datos se analizaron empleando análisis de varianza y prueba de comparaciones múltiples. En los conteos se encontraron bacterias Gram (+), Gram (-), actinomicetos, y los grupos funcionales fijadores de nitrógeno y solubilizadores de fósforo, junto con los hongos Trichoderma spp., Fusarium spp. y Penicillium spp. Los hongos, los actinomicetos y los solubilizadores de fósforo fueron los microorganismos más afectados por los agroquímicos, con reducciones en la abundancia. Las bacterias presentaron comportamientos variables dependiendo del agroquímico y los fijadores de nitrógeno fueron estimulados por los tratamientos. Estos resultados indican que los agroquímicos utilizados en el estudio pueden impactar de diferente manera los microorganismos que se encargan de la descomposición de la materia orgánica.This paper show an analysis of the effect of agrochemicals used in a rice crop on the abundance of Oxisol soil microorganisms in the region of the Eastern Plains of Colombia, under field conditions. Evaluated Agrochemicals were Glyphosate, Bispiribac, Azoxystrobin and Malathion, applied in commercial dosages, in a block design with repeated measures. For the enumeration of microorganisms, soil samples were taken from rhizospheric soil using the transects methodology. From the samples, microbial counts were carried out using the method of dilution in plate and the data were analyzed using the Minitab 14 software using analysis of variance and test for multiple comparisons. In the counts bacteria Gram (+), Gram (-), actinomycetes, and functional groups: nitrogen fixers, and phosphorus solubilizing, together with the fungus, Trichoderma spp., Fusarium spp., and Penicillium spp. were found. In general, fungi, actinomycetes and the phosphorus solubilizing microorganisms were more affected by the agrochemicals with reductions in their abundance. Bacteria presented varying behaviors depending on the agrochemical and the nitrogen fixers were stimulated by the treatments. These results indicate that the chemicals may impact in different ways to the microorganisms that are responsible for the decomposition of organic matter

Genetic diversity of moringa oleifera Lam. in the Northeast of Colombia using RAMs markers

1 recurso en línea (páginas 408-415) : ilustraciones color.Moringa oleifera Lam., also known as Moringa pterygosperma Gaertn., is a fast growing tree, indigenous to Himalaya that has been used as food or as medicine, recognized for its bioactive compounds. In Colombia, moringa has been promoted primarily because of its medicinal properties. However, despite the importance of this phytogenetic resource, there are no studies on its genetic variability. In this study, we analyzed 45 accessions of moringa from four departments in the northeast of Colombia. The DICE and Nei-Li coefficients, at a level of similarity of 0.75, differentiated the population into four genetic groups. The expected heterozygosity was 0.13 for the oligo CT and 0.29 for the oligos CGA and GT. The percentage of polymorphic loci ranged from 31 to 100% for the primers CT and CA, respectively. With the UPGMA grouping, we revealed that the Moringa accessions from Villa del Rosario in Norte de Santander are genetically isolated. The genetic diversity of the studied Moringa accessions was low. This knowledge on the genetic variability of moringa provides a new contribution to Colombian growers that can be used in future breeding programs.Moringa oleifera Lam., también conocida como Moringa pterygosperma Gaertn., es un árbol endógeno de la región Himalaya, de crecimiento rápido que puede alcanzar los 12 m de alto. Moringa es empleado como alimento o como medicina, reconocido por sus compuestos bioactivos. En Colombia, moringa se ha promovido principalmente por sus propiedades medicinales. Sin embargo, a pesar de la importancia de este recurso fitogenético, no existen estudios de su variabilidad genética en el país. En esta investigación, empleando marcadores moleculares microsatélites amplificados al azar (RAMs), se analizaron 45 accesiones de moringa procedentes de 4 departamentos del Nor Oriente de Colombia. Los coeficientes de Dice y Nei-Li a un nivel de similitud de 0,75 diferenciaron la población en 4 grupos genéticos. La heterocigocidad estimada fue de 0,13 para el cebador CT y de 0,29 para los cebadores CGA y GT. El porcentaje de loci polimórfico osciló entre 31 y 100% para los cebadores CT y CA, respectivamente. Por la agrupación UPGMA, se identificó que las accesiones de Villa del Rosario en Norte de Santander están genéticamente aislados. Se encontró que la diversidad genética de las accesiones de Moringa estudiadas es baja. El conocimiento de la variabilidad genética de moringa en las regiones de estudio, proporciona un nuevo aporte a los cultivadores colombianos que puede ser empleado en futuros programas de mejoramiento.Bibliografía: páginas 414-415

Response in root development of Arabidopsis thaliana to leaf extract of Moringa oleifera

Páginas 193-199.La respuesta del crecimiento de las raíces se encuentra mediado por fitorreguladores que participan en todas las etapas de crecimiento y desarrollo de la planta. Un adecuado sistema radicular garantiza el anclaje y absorción de nutrientes para los procesos metabólicos requeridos en sus etapas fenológicas. Las citoquininas (CK) y auxinas (AIA), son fitorreguladores que desempeñan un papel importante en el desarrollo del sistema radicular. Se ha reportado que las hojas de Moringa oleifera son particularmente ricas en zeatina por lo que la aplicación de sus extractos puede tener efecto en el desarrollo radicular. Para entender de manera detallada la respuesta de las raíces al extracto de Moringa oleifera, se utilizó un sistema in vitro con Arabidopsis thaliana usando dosx|ABSTRACT: The root growth response is mediated by hormones that participate in all stages of plant growth and development. A good root system guarantees anchoring and absorption of nutrients for the metabolic processes required in the developmental stages. Cytokinins (CK) and auxins (AIA) are hormones that play an important role in the development of the root system. Moringa oleifera has cytokinins, so the application of their extracts can have an effect on the development of the root system. In order to understand the root response to the Moringa oleifera extract, we used an in vitro system with Arabidopsis thaliana and two experiment conditions. (A) Seeds germinated directly in MS medium with application of the Moringa oleifera extract at different dilutions, which determined how the primary root (PR) growth was affected. (B) Plants were germinated and grown for 8 days in the MS medium, without lateral roots (LR), and transferred to media with different dilutions of the extract. The results showed that (A) the best dilution of Moringa oleifera base extract (KOH 0.05 M) for the germination stimulation was seen in the dilutions of 1 mL, 1.5 mL and 2.0 mL, as well as the treatment with trans Zeathine riboside (ZR) with a concentration of 60 μM, and (B) the basic extract of Moringa oleifera in a ratio of 1.5: 0.5 (extract: KOH 0.05 M) was the best treatment for the development of the primary root (PR) and lateral roots (LR). Further studies are needed to determine the validity of these results in field.Bibliografía: páginas 198-199Artículo revisado por pares

High-Performance Flexible Magnetic Tunnel Junctions for Smart Miniaturized Instruments

Flexible electronics is an emerging field in many applications ranging from in vivo biomedical devices to wearable smart systems. The capability of conforming to curved surfaces opens the door to add electronic components to miniaturized instruments, where size and weight are critical parameters. Given their prevalence on the sensors market, flexible magnetic sensors play a major role in this progress. For many high-performance applications, magnetic tunnel junctions (MTJs) have become the first choice, due to their high sensitivity, low power consumption etc. MTJs are also promising candidates for non-volatile next-generation data storage media and, hence, could become central components of wearable electronic devices. In this work, a generic low-cost regenerative batch fabrication process is utilized to transform rigid MTJs on a 500 {\mu}m silicon wafer substrate into 5 {\mu}m thin, mechanically flexible silicon devices, and ensuring optimal utilization of the whole substrate. This method maintains the outstanding magnetic properties, which are only obtained by deposition of the MTJ on smooth high-quality silicon wafers. The flexible MTJs are highly reliable and resistive to mechanical stress. Bending of the MTJ stacks with a diameter as small as 500 {\mu}m is possible without compromising their performance and an endurance of over 1000 cycles without fatigue has been demonstrated. The flexible MTJs were mounted onto the tip of a cardiac catheter with 2 mm in diameter without compromising their performance. This enables the detection of magnetic fields and the angle which they are applied at with a high sensitivity of 4.93 %/Oe and a low power consumption of 0.15 {\mu}W, while adding only 8 {\mu}g and 15 {\mu}m to the weight and diameter of the catheter, respectively.Comment: 20 pages, 6 figures, Intermag 201