MAGE Proteins and the Regulation of E2F Pathway

Melanoma Antigens Genes (MAGE) constitutes a mutagenic family divided in two subfamilies, MAGE-I and MAGE-II, according to its tissue pattern expression. While MAGE-I in adult humans are only expressed in testis and tumors tissues, those belonging to MAGE-II subfamily are ubiquitously expressed. During the last decade, functional characterization of MAGE proteins points to a role in transcription regulation. E2F1 is a member of the E2F family and is among the transcription factors reported to be modulated by MAGE proteins. In this article we will focus on reported cases of E2F1 modulation by members of MAGE-I and MAGE-II subfamilies and the resulting biological consequences observed in normal and tumor cells.Fil: Ladelfa, Maria Fatima. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Monte, Martín. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentin

O papel do monitor acadêmico na disciplina de leitura e produção de textos em língua portuguesa I

Este Trabalho de Conclusão de Curso tem como objetivo geral averiguar o papel do monitor acadêmico na disciplina de Leitura e Produção de Textos em Língua Portuguesa I (LPT I) ofertada aos alunos do curso de bacharelado em Letras na UFRGS. Perseguindo esse objetivo, o trabalho se divide em cinco partes. A primeira parte apresenta o lugar de onde essa pesquisa começa. A segunda traz a análise da Instrução Normativa nº 03/2013 da Prograd/Sead e uma síntese de outras pesquisas servindo de ponto de partida para a reflexão sobre o papel do monitor na universidade. A terceira parte exemplifica como é o andamento da disciplina de LPT I bem como o seu objeto de estudo. A quarta parte descreve a concepção de língua que baseia as reflexões deste trabalho a partir da Linguística da Enunciação de Émile Benveniste. A quinta parte se destina a discutir sobre o papel do monitor em LPT I, concluindo de que é possível percebê-lo em quatro diferentes posições: o monitor um pouco professor, um pouco aluno; o monitor como um modelo de aluno; o monitor em um metalugar — ensina escrita ao mesmo tempo que aprende escrita —; e o monitor como interlocutor e mediador de letramento.This bachelor’s thesis aims to make a discussion about the role of the university monitor in the discipline Leitura e Produção de textos em Língua Portuguesa I (LPT I), which is offered to Letras’s Bachelor students at UFRGS. To reach this objective, this work is divided into four parts. The first one shows where this research starts. The second one brings an analysis of the Instrução Normativa nº 03/2013 from Prograd/Sead as well as a summary of other research, serving as a starting point for the following discussion. The third part exemplifies how the LPT I classes are handled and its purpose. The fourth part describes the concept of language through Emile Benveniste’s Linguistics of Enunciation on which the following reflections are going to be based. The fifth part intends to discuss the roles of the monitor in LPT I concluding that it is possible to divide them into four different positions: the monitor as a teacher and as a student; the monitor as a student model; the monitor in a meta place — teaches writing at the same time as learns writing; and the monitor as interlocutor and mediator

In vitro growth properties of bovine herpesvirus type 5 (BoHV-5) A663 strain and study of the Us3 protein function

Este trabajo de tesis contribuyo a la caracterizacion de la cepa argentina A663 de Herpesvirus Bovino tipo 5 (BoHV-5) mediante el estudio de sus propiedades replicativas in vitro y del rol de la proteina Us3. En el primer caso se realizaron cineticas de crecimiento y se evaluaron los tamanos de las placas de lisis y de infeccion de las cepas A663 y N569 de BoHV-5. La produccion total de particulas virales infectivas en funcion del tiempo fue similar entre ambas cepas, sin embargo la cepa A663 resulto menos eficiente en la liberacion de particulas virales al medio extracelular y en la dispersion celula a celula, observandose para la cepa A663 una reduccion del 90% y del 80% en el tamano de la placa de lisis y de infeccion, respectivamente. Por otro lado, se secuencio la region codificante para la proteina Us3 de la cepa A663 de BoHV-5 y se observo un alto porcentaje de homologia con las secuencias correspondientes a otras cepas de BoHV-5. Mediante las tecnicas de Northern y Western blot se demostro que el gen us3 se expresa tempranamente (desde los 30 minutos post infeccion) y de manera prolongada (hasta las 48 horas post infeccion). Los ensayos in vitro se realizaron utilizando construcciones que expresaban la proteina Us3 wt o una version mutante de esta proteina que carece de actividad de proteina quinasa, fusionadas a la proteina fluorescente ECFP (US3-ECFP y Us3K261D-ECFP). Se observo que la proteina Us3 de BoHV-5 induce el redondeamiento celular y provoca el desensamblado de las fibras de estres, siendo estos efectos independientes de su funcion de quinasa. Ademas, la proteina mutante Us3K261D disminuyo la formacion de proyecciones de celulares y modifico la localizacion subcelular de la proteina Us3 de BoHV-5. En conjunto, los resultados obtenidos permitieron conocer las propiedades replicativas in vitro de la cepa A663 de BoHV-5 y constituyeron el primer reporte sobre el estudio de la funcion de la proteina Us3 de BoHV-5.This thesis contributed to the characterization of the Argentinean bovine herpesvirus type 5 (BoHV-5) A663 strain by studying its in vitro growth properties and the function of the Us3 protein. Firstly, growth kinetics, lysis and infection plaque size assays were performed for BoHV-5 A663 and N569 strains. The total amount of infection virus produced was similar between both strains at each time assayed; however, A663 strain was less efficient than N569 strain in releasing infective viral particles to the extracellular media and in cell-to-cell spread, as shown by a reduction of 90% and 80% in its lysis and infection plaque size, respectively. On the other hand, the region encoding the Us3 protein of BoHV-5 A663 strain was sequenced and high homology was observed between it and other sequences of BoHV-5 strains. Then, early (from 30 minutes post infection) and prolong (up to 48 hours post infection) expression of us3 gene was demonstrated by Northern and Western blots assays. Finally, in vitro studies were performed with genetic constructions to express wt Us3 protein or a mutated version of this protein lacking its kinase activity, fused to the fluorescent protein ECFP (Us3-ECFP and Us3K261D-ECFP). In transient transfection assays it was observed that Us3 BoHV-5 protein induced cell rounding and stress fiber breakdown independently of its kinase activity. Besides, the point mutation in the Us3K261D protein reduced cell projections formation and modified the subcellular localization of BoHV-5 Us3 protein. Taken together, these results allowed the assessment of the in vitro growth properties of BoHV-5 A663 strain and constituted the first report of the function of the BoHV-5 Us3 protein.Fil:Ladelfa, María Fátima. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

Dengue Non-structural Protein 5 Polymerase Complexes With Promyelocytic Leukemia Protein (PML) Isoforms III and IV to Disrupt PML-Nuclear Bodies in Infected Cells

Dengue virus (DENV) threatens almost 70% of the world's population, with no therapeutic currently available. The severe, potentially lethal forms of DENV disease (dengue hemorrhagic fever/dengue shock syndrome) are associated with the production of high level of cytokines, elicited as part of the host antiviral response, although the molecular mechanisms have not been fully elucidated. We previously showed that infection by DENV serotype 2 (DENV2) disrupts promyelocytic leukemia (PML) gene product nuclear bodies (PML-NBs) after viral protein translation in infected cells. Apart from playing a key role as the nucleating agent in forming PML-NBs, PML has antiviral activity against various viruses, including DENV. The present study builds on this work, showing for the first time that all four DENV serotypes elicit PML-NB breakdown. Importantly, we show for the first time that of the nuclear localizing proteins of DENV, DENV non-structural protein (NS) 5 polymerase alone is sufficient to elicit PML-NB disassembly, in part through complexing with PML isoforms III and IV, but not other PML isoforms or other PML-NB components. The results raise the possibility that PML-NB disruption by nuclear localized NS5 contributes to DENV's suppression of the host antiviral response.Fil: Giovannoni, Federico. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ladelfa, Maria Fatima. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica; ArgentinaFil: Monte, Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica; ArgentinaFil: Jans, David A.. Monash University; AustraliaFil: Hemmerich, Peter. Leibniz Institute On Aging; AlemaniaFil: Garcia, Cybele. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica; Argentin

Comparative study on the in vitro and in vivo properties of two bovine herpesvirus-5 reference strains

<p>Abstract</p> <p>Background</p> <p>Bovine herpesvirus 5 (BoHV-5) is an alphaherpesvirus responsible for meningoencephalitis in young cattle and it is antigenically and genetically related to bovine herpesvirus 1. BoHV-5 outbreaks are sporadic and restricted in their geographical distribution, being mostly detected in the Southern hemisphere. The N569 and A663 strains are prototypes of the "a" and "b" subtypes of BoHV-5, however, scarce information about their <it>in vitro </it>and <it>in vivo </it>properties is currently available.</p> <p>Methods</p> <p>For the <it>in vitro </it>comparison between BoHV-5 A663 and N569 strains, viral growth kinetics, lysis and infection plaque size assays were performed. Additionally, an experimental infection of cattle with BoHV-5 A663 and N569 strains was carried out. Viral excretion, development of neurological signs, presence of specific antibodies in serum and nasal swabs and presence of latent BoHV-5 DNA in trigeminal ganglion, were analyzed. Histopathological examination of samples belonging to inoculated animals was also performed.</p> <p>Results</p> <p>The lytic capacity and the cell-to-cell spread was lower for the A663 strain compared to the N569 strain, however, the production of total infectious viral particles was similar between both strains. Concerning the <it>in vivo </it>properties, the A663 and N569 strains are able to induce similar degrees of pathogenicity in cattle.</p> <p>Conclusions</p> <p>Our results show that the A663 strain used in this study is less adapted to <it>in vitro </it>replication in MDBK cells than the N569 strain and, although slight differences were observed, both strains are able to induce a similar degree of virulence in the natural host.</p

In vitro-generated interspecific recombinants between bovine herpesviruses 1 and 5 show attenuated replication characteristics and establish latency in the natural host

peer reviewe

Characterization of BoHV-5 field strains circulation and report of transient specific subtype of bovine herpesvirus 5 in Argentina

<p>Abstract</p> <p>Background</p> <p>Bovine herpesvirus 5 (BoHV-5) is a member of the subfamily <it>Alphaherpesvirinae </it>responsible for meningo-encephalitis in young cattle. The first case of bovine meningo-encephalitis associated with a herpesvirus infection was reported in Australia. The current geographical distribution of BoHV-5 infection is mainly restricted to South America, especially Brazil and Argentina. Outbreaks of BoHV-5 are regularly observed in Argentina suggesting the circulation of the virus in the bovine population.</p> <p>Results</p> <p>Seventeen field strains of BoHV-5 isolated from 1984 to now were confirmed by differential PCR and subjected to restriction endonuclease analysis (REA). Viral DNA was cleaved with BstEII which allows the differentiation among subtypes a, b and non a, non b. According to the REA with BstEII, only one field strain showed a pattern similar to the Argentinean A663 strain (prototype of BoHV-5b). All other isolates showed a clear pattern similar to the Australian N569 strain (prototype of BoHV-5a) consistent with the subtypes observed in Brazil, the other South-American country where BoHV-5 is known to be prevalent. The genomic region of subtype b responsible for the distinct pattern was determined and amplified by PCR; specifically a point mutation was identified in glycoprotein B gene, on the BstEII restriction site, which generates the profile specific of BoHV-5b.</p> <p>Conclusions</p> <p>This is the first report of circulation of BoHV-5a in Argentina as the prevailing subtype. Therefore the circulation of BoHV-5b was restricted to a few years in Argentina, speculating that this subtype was not able to be maintained in the bovine population. The mutation in the gB gene is associated with the difference in the restriction patterns between subtypes "a" and "b".</p