321 research outputs found
Geminivirus Rep Protein Interferes with the Plant DNA Methylation Machinery and Modifies the Host Epigenome
The apparent simplicity of viruses hides the complexity of their interactions with their hosts. Viruses are masters at circumventing host defenses and manipulating the cellular environment for their own benefit. The replication of the largest known family of single-stranded DNA viruses, Geminiviridae, is impaired by DNA methylation and Arabidopsis mutants affected in cytosine methylation are hypersusceptible to geminivirus infection. This implies that plants might use methylation as a defense against geminiviruses and that the viral genome is a target for plant DNA methyltransferases. We have found a novel counter-defense strategy used by geminiviruses, that reduces the expression of the plant maintenance DNA methyltransferases, MET1 and CMT3, in both, locally and systemically infected tissues. Furthermore, we demonstrated that the virus-mediated repression of these two maintenance DNA methyltransferases is widely spread among different geminivirus species. Additionally, we identified Rep as the geminiviral protein responsible for the repression of MET1 and CMT3, and another viral protein, C4, as an ancillary player in MET1 downregulation. The presence of Rep, suppresses TGS of an Arabidopsis transgene and of host loci whose expression is strongly controlled by CG methylation. Bisulfite sequencing analyses showed that the expression of Rep caused a substantial reduction in the levels of DNA methylation at CG sites. Our findings suggest that Rep, the only viral protein essential for geminiviral replication, displays TGS suppressor activity through a mechanism distinct from the one thus far described for geminiviruses.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Geminivirus Rep Protein Interferes with the Plant DNA Methylation Machinery and Suppresses Transcriptional Gene Silencing
Cytosine methylation is an epigenetic mark that promotes gene silencing and plays an important role in genome defense against transposons and invading DNA viruses. So far just one geminiviral protein, C2 from Tomato golden mosaic virus (TGMV), Beet curly top virus(BCTV) and Beet severe curly top virus (BSCTV) and a betasatellite protein from Tomato yellow leaf curl China virus (TYLCCNV), have been shown to act as TGS suppressors by interfering with the proper functioning of the plant methylation cycle. We have found that geminiviral infection reduces the expression of the plant maintenance DNA methyltransferases, MET1 and CMT3, in both, locally and systemically infected tissues of Arabidopsis and Nicotianabenthamiana and we demonstrated that the virus-mediated repression of these two maintenance DNA methyltransferases is widely spread among different geminivirus species (TGMV, African cassava mosaic virus (ACMV), Tomato yellow leaf curl Sardinia virus (TYLCSV) and Tomato yellow leaf curl virus (TYLCV-Mld).Furthermore, we have identified Rep as the geminiviral protein responsible for the repression of MET1 and CMT3, and another viral protein, C4, as an ancillary player in MET1 downregulation. The presence of Rep, suppresses TGS of an Arabidopsistransgene and of host loci whose expression is strongly controlled by CG methylation. Additionally, bisulfite sequencing analyses showed that the expression of Rep caused a substantial reduction in the levels of DNA methylation at CG sites. Our findings suggest that Rep, the only viral protein essential for geminiviral replication, displays TGS suppressor activity through a mechanism distinct from the one thus far described for geminiviruses.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Mediación Familiar en México. Avances en Justicia alternativa para conflictos familiares
This article is the result of a review that aimed to analyze the development of mediation directed at the states and its impulse in family mediation, as well as the progress they have made regarding the developments of this alternative justice process to national level, so to make proposals on the matter, it is necessary to inquire about how this alternative process is currently and how they currently contemplate it, from their specialized legislation to the numbers of issues that have been resolved in the last year, so that, according to statistics and legislation, those advances that have been made in family mediation will be analyzed.El presente artículo es resultado de una revisión que tuvo por objetivo analizar el desarrollo de la mediación dirigida a las entidades federativas y su impulso en la mediación familiar, así como los avances que estas han tenido respecto a los desarrollos de este proceso de justicia alternativa a nivel nacional, por lo que para hacer propuestas en la materia, se necesita indagar respecto a cómo se encuentra este proceso alternativo en la actualidad y de qué manera la contemplan actualmente, desde sus legislaciones especializadas hasta los números de asuntos que han resuelto en el último año, de modo que, se analizará conforme a las estadísticas y las legislaciones, aquellos avances que han tenido en la mediación familiar
Studying the role of the strawberry Fra protein family in the flavonoid metabolism during fruit ripening
Strawberry fruits are highly appreciated worldwide due to their pleasant flavor and aroma and to the health benefits associated to their consumption. An important part of these properties is due to their content in secondary metabolites, especially phenolic compounds, of which flavonoids are the most abundant in the strawberry fruit. Although the flavonoid biosynthesis pathway is uncovered, little is known about its regulation.
The strawberry Fra a (Fra) genes constitute a large family of homologs of the major birch pollen allergen Bet v 1 and for which no equivalents exist in Arabidopsis. Our group has shown that Fra proteins are involved in the formation of colored compounds in strawberries (Muñoz et al., 2010), which mainly depends on the production of certain flavonoids; that they are structurally homologs to the PYR/PYL/RCAR Arabidopsis ABA receptor, and that they are able to bind flavonoids (Casañal et al., 2013). With these previous results, our working hypothesis is that the Fra proteins are involved in the regulation of the flavonoids pathway. They would mechanistically act as the ABA receptor, binding a protein interactor and a ligand to regulate a signaling cascade and/or act as molecular carriers.
The main objective of this research is to characterize the Fra family in strawberry and gain insight into their role in the flavonoid metabolism.
By RNAseq expression analysis in ripening fruits we have identified transcripts for 10 members of the Fra family. Although expressed in all tissues analyzed, each family member presents a unique pattern of expression, which suggests functional specialization for each Fra protein.
Then, our next approach was to identify the proteins that interact with Fras and their ligands to gain knowledge on the role that these proteins play in the flavonoids pathway.
To identify the interacting partners of Fras we have performed a yeast two hybrid (Y2H) screening against cDNA libraries of strawberry fruits at the green and red stages. A protein that shares a 95% homology to the Heat stress transcription factor A-4-C like of Fragaria vesca (HSA4C) interacts specifically with Fra1 and not with other family members, which suggests functional diversification of Fra proteins in specific signaling pathways. The Y2H screening is not yet saturated, so characterization of other interacting proteins with other members of the Fra family will shed light on the functional diversity within this gene family.
This research will contribute to gain knowledge on how the flavonoid pathway, and hence, the fruit ripening, is regulated in strawberry; an economically important crop but for which basic research is still very limited.
References:
Muñoz, C, et al. (2010). The Strawberry Fruit Fra a Allergen Functions in Flavonoid Biosynthesis. Molecular Plant, 3(1): 113–124.
Casañal, A, et al (2013). The Strawberry Pathogenesis-related 10 (PR-10) Fra a Proteins Control Flavonoid Biosynthesis by Binding Metabolic Intermediates. Journal of Biological Chemistry, 288(49): 35322–35332.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
The favourable opinion and the crisis of Abengoa S.A.
Treball Final de Grau en Finances i Comptabilitat. Codi: FC1049. Curs: 2017/2018The aim of this report is the economic-financial analysis of Abengoa S.A, a company
that has been a benchmark in Spain for its evolution and growth in the energy sector.
The analysis covers the period 2011-2014, years previous to the declaration of
bankruptcy, as one of the objectives of this analysis is to see if the data presented by
the company could have predicted the risk of declaring insolvency proceedings.
On July 21, 2015, the new Accounting Audit Law, Law 22/2015 was published. In
general, this new Law is for all companies with economic activity; however the main
changes affect especially the Public Interest Entities.
The articles of this law that affect the Public Interest Entities will be analyzed, in order
to determine if their application to the audit report of Abengoa SA before the
declaration of bankruptcy, would have been useful in detecting the serious risks that
the company had.
The choice of this company is related to the possibility of combining two topics: the
declaration of bankruptcy and the new Law 22/2015, both issues being related to the
current and economic news
Geminivirus Rep Protein Interferes with the Plant DNA Methylation Machinery and Suppresses Transcriptional Gene Silencing
Viruses are masters at circumventing host defenses and manipulating the cellular environment for their own benefit. The replication of the largest known family of single-stranded DNA viruses, Geminiviridae, is impaired by DNA methylation but the fact that plants might use methylation as a defense against geminiviruses and the impact that viral genome methylation may have during the infection, remain controversial.
We have found that geminiviruses reduce the expression of the plant maintenance DNA methyltransferases, MET1 and CMT3, in both, locally and systemically infected tissues. Furthermore, we demonstrated that the virus-mediated repression of these two maintenance DNA methyltransferases is widely spread among different geminivirus species and we have identified Rep as the geminiviral protein responsible for the repression of MET1 and CMT3. The presence of Rep, suppresses transcriptional gene silencing (TGS) of an Arabidopsis transgene and of host loci whose expression is strongly controlled by MET1. Bisulfite sequencing analyses showed that the expression of Rep caused a substantial reduction in the levels of DNA methylation at certain loci at CG sites. The biological relevance of these findings and the role of Rep as a TGS suppressor will be discussed.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
La rentabilidad basada en el costo de venta de productos hidrobiológicos. CRISER E.I.R.L. Paita, 2015 - 2019
La presente investigación titulada la rentabilidad basada en el costo de venta de productos hidrobiológicos. CRISER E.I.R.L. Paita,2015-2019.Tuvo como objetivo general determinar la rentabilidad de la empresa. Se utilizó el diseño no experimental-transversal de tipo descriptivo, la muestra se constituyó por 20
colaboradores y 10 documentos. En la recolección de datos se aplicó como instrumento de medición un cuestionario para la variable costo de venta, luego, se procedió a analizar mediante el software estadístico SPSS 22, logrando medir el
nivel de confiabilidad a través del Alfa de Cronbach. Y asimismo se utilizó guías de análisis documental para la variable rentabilidad, para ambos instrumentos la validez se dispuso a juicio de 3 expertos. Finalmente, se obtuvo como conclusión que hay falta de control en el registro contable en los elementos del costo de ventas, asimismo se encontró otros potenciales problemas en los
cuales incurre la empresa, el no tener políticas de contratación de personal genera que este costo no se registre en su totalidad, por otro lado, frente a la
contratación de servicios de terceros, suele convenir con proveedores de
servicios no formales teniendo como consecuencias un indicador de rentabilidad no real
Clima organizacional y desempeño laboral del personal administrativo de la UGEL Santa, 2022
Esta investigación tuvo como finalidad determinar si existe relación entre el clima
organizacional y el desempeño laboral del personal administrativo de la UGEL
Santa, para lo cual se empleó una población y muestra de 100 trabajadores,
obteniendo un muestreo no probabilístico.
La metodología empleada se consideró un enfoque paradigma positivista, de tipo
cuantitativo y de diseño no experimental correlacional. Asimismo la técnica
empleada fue la encuesta y el instrumento conformada por 2 cuestionarios de 22
y 16 ítems, validada por 2 expertos, obteniendo un excelente grado de
confiabilidad.
Como conclusión se determinó que existe una correlación positiva muy fuerte
entre las variables clima organizacional y desempeño laboral, debido a que el
coeficiente de correlación salió 0.838, y la significancia bilateral salió 0.000, el
cual es menor al margen de error (0.05), esto porque el clima organizacional está
en un proceso de implementación y que es de aceptación total por parte de la
población. Sin embargo, se tiene que continuar en su aplicación con la finalidad
de aumentar el desempeño laboral de los trabajadores. A su vez, se determinó
que en la variable clima organizacional el 40% tienen una percepción de nivel
bueno; el 19% un nivel regular, y el 41% tienen un nivel malo; en la variable
desempeño laboral el 38% tienen un nivel alto, el 44% tienen un nivel medio, y el
18% tienen un nivel bajo
Clima organizacional en el desempeño laboral en una institución educativa del distrito de Chaclacayo 2021
En el presente trabajo de investigación se determinó la incidencia que existe entre el
clima organizacional en el desempeño laboral en la I. E. Felipe Santiago Estenos,
Chaclacayo, teniendo en cuenta la teoría de Mayo para la primera variable y Campbell
para la segunda.
Se utilizó el enfoque cuantitativo, diseño no experimental, descriptivo-explicativo -
causal, transversal, básica, recogiendo información a través de dos cuestionarios
referente a Clima organizacional y desempeño laboral. Esta investigación estuvo
conformada por una muestra de 72 personas, a quienes se aplicó la encuesta, los que
fueron sometidos al juicio de tres expertos para comprobar su validez del contenido y
para la confiabilidad se usó el alfa de Crombach obteniéndose los coeficientes de
0,916 para el cuestionario de Clima organizacional y 0,901 para el de Desempeño
laboral, indicando una alta confiabilidad.
En los resultados se niega la hipótesis nula, es decir, la prueba logística es
significativa. En tal sentido el clima organizacional incide en el desempeño laboral. De
igual forma se observó, respecto a la prueba Nagelkerke, un valor de ,258 lo cual
señaló que el clima organizacional incide en 25,8%
Importance of the temperature in the interaction plant-geminivirus
Introduction. Geminivirusare plant viruses that have circular single-stranded DNA (ssDNA) genome encapsidated in twinned quasi-icosahedral (geminate) virionsand are a serious threat to diverse economically important crops such as tomato, pepper and cassava. TYLCV (Tomato yellow leaf curl virus) belongs to the genus begomovirus which is by far, the largest of the seven genera in the family Geminiviridae and it is a pathogen that induces a devastating disease in tomato in the Mediterranean region. Cultured tomatoes are often exposed to a combination of extreme heat and infection with TYLCV and this combination leads to intense disease symptoms and yield losses.The impact of temperature over the interaction tomato-
TYLCVhas been characterized (Ghandi et al., 2016) but these results seem to be contradictory to our findings.
Objective. The main objective of this work is to improve our understanding of the impact that high temperature has in the interaction plant-geminivirus.Material and methods. Nicotianabenthamiana plants were infected with TYLCV and growth in a chamber at 21 ºC or at 35 ºC. The amount of virus, symptoms, plant height and number of leaves were monitored at 14, 21 and 28 dpi (days post-infection). Three biological replicates were performed, each containing 15 infected plants and 10 non-infected plants (mock).
Results. No differences were observed between non-infected and infected plants at both temperatures, in plant height or in the number of leaves, but the amount of virus and the severity of symptoms were significantly reduced in plants at high temperature.
Conclusions. We conclude that TYLCV yield decreases in N. benthamiana due to high temperature and ongoing experiments in tomato TYLCV-infected plants will let us determine the
importance of this finding in an agronomical important crop and to compare our results with the published data.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
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