Relación de ototoxicidad y cisplatino en pacientes de oncología en dos hospitales de la región metropolitana

Tesis (Magíster en Fonoaudiología)El Cáncer es una enfermedad en las que células anormales se dividen sin control y pueden invadir otros tejidos. Uno de los medicamentos que se utiliza en ciertos tipos de cánceres como son de cabeza/cuello, ováricos y germinales, es el cisplatino fármaco quimioterapéutico que es administrado de forma intravenosa. Los efectos secundarios y su gravedad dependen de diversos factores. Dentro de los efectos secundarios que produce este medicamento antineoplásico se encuentra la hipoacusia y/o el tinnitus. La presente investigación es un estudio analítico, cuasi experimental y longitudinal, que tiene como objetivo verificar si existe alguna relación entre la quimioterapia con cisplatino y la ototoxicidad, en aquellos pacientes que presentaron cáncer (germinal y/o cabeza-cuello) y que fueron tratados con este medicamento antineoplásico. La muestra obtenida se encontró entre los 4 a 73 años, pertenecientes al sistema de salud público atendido en 2 hospitales de la Región Metropolitana. La obtención de datos se llevó a cabo a través de la revisión de fuentes secundarias (documentales) y examen auditivo (Audiometría). Tras el análisis de resultados, se encontró que el cisplatino está relacionado con la hipoacusia en aquellos pacientes posterior a sus quimioterapias con este medicamento, más del 50 % de los pacientes presentó hipoacusia o tinnitus post tratamiento, la presencia de ototoxicidad es mayor en pacientes pequeños y adultos mayores que en adultos jóvenes, el sexo no tiene mayor relevancia en la presencia de ototoxicidad, la cantidad de dosis no es predictiva ante la presencia de hipoacusia a diferencia de la cantidad de ciclos, por ende la presencia de hipoacusia posterior a las quimioterapias con cisplatino dependerá de una serie de factores, tales como: edad, fisiología auditiva, platino en el plasma no desechado por los riñones, ciclos, etc. De acuerdo a los resultados de la investigación, se concluye que es de gran relevancia que los pacientes que cursan con cáncer y que por consiguiente son tratados con cisplatino se deben realizar una evaluación auditiva durante y al término de su proceso quimioterapéutico, además se sugiere audiometría anual en el seguimiento de los pacientes.Cancer is a disease in which abnormal cells are divided out of control and may invade other tissues. One of the drugs used in certain types of cancer such as head and neck, ovarían and germinal, is cisplatin which is a chemotherapy medication given intravenously. The second effects and their severity depend on the dose of cisplatin given and other factors in addition. However, this antineoplastic medication may cause serious side effects, such as hearing loss and/or tinnitus. This current research is a quasi-experimental and longitudinal analytical study, which aims to verifying whether a relationship exists between chemotherapy with cisplatin and ototoxicity in those patients who presented germinal and/or head-neck cancers, and who were treated with cisplatin between the ages of 4 and 73 years old. These patients belonged to the public health system attended in 2 hospitals from Metropolitan Region. The collection of data was carried out through secondary data review (documentary references) and a hearing test (Audiometry). According to the analysis of results, it was found that cisplatin is related to hearing loss in patients after chemotherapy with cisplatin. Over 50% of the patients presented hearing loss or tinnitus after their treatment. The presence of ototoxicity is greater in children and older adults than in young adults. Gender was of no relevance in ototoxicity presence or absence. The dosage in milligrams is not predictive before the presence of hearing loss unlike the number of cycles. And the presence of hearing loss after chemotherapy with cisplatin will depend on a number of factors, such as: age, hearing physiology, platinum amount in plasma which has not been removed from the body by the kidneys, cycles, and so on. In the view of the above results, it is concluded that it is vital for patients who suffer from cancer, and consequently, are treated with cisplatin to have a hearing evaluation during and at the end of their chemotherapeutic process. Moreover, it is suggested that patients have an annual audiometry for control patient follow-up

Consistent prediction of GO protein localization

The GO-Cellular Component (GO-CC) ontology provides a controlled vocabulary for the consistent description of the subcellular compartments or macromolecular complexes where proteins may act. Current machine learning-based methods used for the automated GO-CC annotation of proteins suffer from the inconsistency of individual GO-CC term predictions. Here, we present FGGA-CC+, a class of hierarchical graph-based classifiers for the consistent GO-CC annotation of protein coding genes at the subcellular compartment or macromolecular complex levels. Aiming to boost the accuracy of GO-CC predictions, we make use of the protein localization knowledge in the GO-Biological Process (GO-BP) annotations to boost the accuracy of GO-CC prediction. As a result, FGGA-CC+ classifiers are built from annotation data in both the GO-CC and GO-BP ontologies. Due to their graph-based design, FGGA-CC+ classifiers are fully interpretable and their predictions amenable to expert analysis. Promising results on protein annotation data from five model organisms were obtained. Additionally, successful validation results in the annotation of a challenging subset of tandem duplicated genes in the tomato non-model organism were accomplished. Overall, these results suggest that FGGA-CC+ classifiers can indeed be useful for satisfying the huge demand of GO-CC annotation arising from ubiquitous high throughout sequencing and proteomic projects.Fil: Spetale, Flavio Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas. Universidad Nacional de Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas; ArgentinaFil: Arce, Debora Pamela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Krsticevic, Flavia Jorgelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas. Universidad Nacional de Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas; Argentina. Universidad Tecnológica Nacional. Facultad Regional San Nicolás; ArgentinaFil: Bulacio, Pilar. Universidad Tecnológica Nacional. Facultad Regional San Nicolás; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas. Universidad Nacional de Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas; ArgentinaFil: Tapia, Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas. Universidad Nacional de Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas; Argentin

A pipeline design for downloading and analyzing promoter sequences in solanum lycopersicum

Se presenta el desarrollo de una arquitectura en pipeline que automatiza la descarga de promotores de Solanum lycopersicum desde la Sol Genomics Network y luego los analiza con los programas MEME y TOMTOM. El código está disponible en www.github.com/lalebot/pip-prom-tom y utiliza Git como software de control de versiones. Se combina el uso de threads en Python, expresiones regulares y base de datos SQLite para que conjuntamente disminuyan el tiempo de descarga de los promotores y optimicen la utilización de recursos informáticos. La metodología que presenta este trabajo es potencialmente aplicable a otras áreas biológicas.A pipeline architecture is implemented to automatize gene promoter sequence download from tomato genome Solanum lycopersicum annotated in Sol Genomics Network. Output gene promoters can be analyzed with MEME and TOMTOM programs. The code is available at www.github.com/lalebot/pip-prom-tom and Git is used as ontrol versions software. Combined Python threads, regular expressions, and SQLite databases are used to reduce time for downloading sequences and optimize informatic resources. The methodology presented in this work is potentially applicable to other biological fields.Fil: Pistilli, Alejandro D.. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias; ArgentinaFil: Pratta, Guillermo Raúl. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Angelone, Laura Monica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas. Universidad Nacional de Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas; ArgentinaFil: Arce, Debora Pamela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; Argentin

Targeting hodgkin and reed–sternberg cells with an inhibitor of heat-shock protein 90: Molecular pathways of response and potential mechanisms of resistance

Classical Hodgkin lymphoma (cHL) cells overexpress heat-shock protein 90 (HSP90), an important intracellular signaling hub regulating cell survival, which is emerging as a promising therapeutic target. Here, we report the antitumor effect of celastrol, an anti-inflammatory compound and a recognized HSP90 inhibitor, in Hodgkin and Reed-Sternberg cell lines. Two disparate responses were recorded. In KM-H2 cells, celastrol inhibited cell proliferation, induced G0/G1 arrest, and triggered apoptosis through the activation of caspase-3/7. Conversely, L428 cells exhibited resistance to the compound. A proteomic screening identified a total of 262 differentially expressed proteins in sensitive KM-H2 cells and revealed that celastrol’s toxicity involved the suppression of the MAPK/ERK (extracellular signal regulated kinase/mitogen activated protein kinase) pathway. The apoptotic effects were preceded by a decrease in RAS (proto-oncogene protein Ras), p-ERK1/2 (phospho-extracellular signal-regulated Kinase-1/2), and c-Fos (proto-oncogene protein c-Fos) protein levels, as validated by immunoblot analysis. The L428 resistant cells exhibited a marked induction of HSP27 mRNA and protein after celastrol treatment. Our results provide the first evidence that celastrol has antitumor effects in cHL cells through the suppression of the MAPK/ERK pathway. Resistance to celastrol has rarely been described, and our results suggest that in cHL it may be mediated by the upregulation of HSP27. The antitumor properties of celastrol against cHL and whether the disparate responses observed in vitro have clinical correlates deserve further research.Fil: Segges, Priscilla. Instituto Nacional de Câncer; BrasilFil: Corrêa, Stephany. Instituto Nacional de Câncer; BrasilFil: Du Rocher, Bárbara. Fundación Oswaldo Cruz; Brasil. Instituto Nacional de Câncer; BrasilFil: Vera Lozada, Gabriela. Instituto Nacional de Câncer; BrasilFil: Krsticevic, Flavia Jorgelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas. Universidad Nacional de Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas; ArgentinaFil: Arce, Debora Pamela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Sternberg, Cinthya. Universidade Federal do Rio de Janeiro; BrasilFil: Abdelhay, Eliana. Instituto Nacional de Câncer; BrasilFil: Hassan, Rocio. Instituto Nacional de Câncer; Brasi

Regulatory motifs found in the small heat shock protein (sHSP) gene family in tomato

Background: In living organisms, small heat shock proteins (sHSPs) are triggered in response to stress situations. This family of proteins is large in plants and, in the case of tomato (Solanum lycopersicum), 33 genes have been identified, most of them related to heat stress response and to the ripening process. Transcriptomic and proteomic studies have revealed complex patterns of expression for these genes. In this work, we investigate the coregulation of these genes by performing a computational analysis of their promoter architecture to find regulatory motifs known as heat shock elements (HSEs). We leverage the presence of sHSP members that originated from tandem duplication events and analyze the promoter architecture diversity of the whole sHSP family, focusing on the identification of HSEs. Results: We performed a search for conserved genomic sequences in the promoter regions of the sHSPs of tomato, plus several other proteins (mainly HSPs) that are functionally related to heat stress situations or to ripening. Several computational analyses were performed to build multiple sequence motifs and identify transcription factor binding sites (TFBS) homologous to HSF1AE and HSF21 in Arabidopsis. We also investigated the expression and interaction of these proteins under two heat stress situations in whole tomato plants and in protoplast cells, both in the presence and in the absence of heat shock transcription factor A2 (HsfA2). The results of these analyses indicate that different sHSPs are up-regulated depending on the activation or repression of HsfA2, a key regulator of HSPs. Further, the analysis of protein-protein interaction between the sHSP protein family and other heat shock response proteins (Hsp70, Hsp90 and MBF1c) suggests that several sHSPs are mediating alternative stress response through a regulatory subnetwork that is not dependent on HsfA2. Conclusions: Overall, this study identifies two regulatory motifs (HSF1AE and HSF21) associated with the sHSP family in tomato which are considered genomic HSEs. The study also suggests that, despite the apparent redundancy of these proteins, which has been linked to gene duplication, tomato sHSPs showed different up-regulation and different interaction patterns when analyzed under different stress situations.Fil: Arce, Debora Pamela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Spetale, Flavio Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas. Universidad Nacional de Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas; ArgentinaFil: Krsticevic, Flavia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas. Universidad Nacional de Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas; ArgentinaFil: Cacchiarelli, Paolo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Las Rivas, Javier De. Universidad de Salamanca; EspañaFil: Ponce, Sergio. Universidad Tecnológica Nacional. Facultad Reg.san Nicolas. Secretaria de Ciencia y Tecnología; ArgentinaFil: Pratta, Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Tapia, Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas. Universidad Nacional de Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas; Argentin

Independent transcriptomic and proteomic networks reveal common differentially expressed chaperone and interactor genes during tomato cv. Micro-Tom fruit ripening

Heat Shock Proteins (HSPs) are a superfamily of chaperones that have been characterized in different organisms. In plants, HSPs contribute to abiotic stress responses and development. The aim of this work was to perform an integrative analysis using bioinformatic and inferential approaches based on protein-protein interactions (PPI) network building, using transcriptomic and proteomic public data from Solanum lycopersicum cultivar (cv.) Micro-Tom during fruit ripening. We were able to identify specific chaperone networks for each maturing stage at both transcriptional and proteomic levels. Also, we noted that the number of induced chaperones was higher at the transcriptomic level than the proteomic one and increased as the fruit matured. Additionally, we identified clusters at both levels during advanced stages of ripening that were over-represented by HSP families (HSP70 and HSP20), chaperones (Proteasome assembly chaperone) and common protein interactors associated with protein folding, protein synthesis and degradation, and response to stress (Glutathione-S-transferase or GST; Endoplasmic reticulum auxin binding protein ER-ABP; tetratricopeptide repeat protein-ripening regulated protein or TRP-RRP). Finally, we found that some of these up-regulated chaperones show the presence of heat shock element (HSE) motifs in their 5′-untranslated regions (5´UTRs). Our combined inferential bioinformatics approach allowed us to integrate RNA, protein expression and co-expression levels of chaperones involved in cv. Micro-Tom fruit ripening. Statement of significance of the study: The Chaperone network is largely characterized by diverse families including Heat Shock Proteins (HSPs), which participate in the refolding of denatured proteins in physiological processes such as developmental changes and abiotic stress response. In the present work, we performed the integrative analysis of transcriptomic and proteomic publicly available data from Solanum lycopersicum cv. Micro-Tom to describe interactome networks at both primary stages (transcription and translation) of gene expression in tomato fruits. Our strategy based on interactomics allowed us to identify specific networks at both levels for each maturing stage at fruit ripening, discovering new interactions and characterizing chaperones and co-chaperons forming these complex biological protein networks during tomato fruit ripening.Fil: Goytia Bertero, Valentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de San Nicolás. - Universidad Tecnológica Nacional. Facultad Regional San Nicolás. Centro de Investigaciones y Transferencia de San Nicolás; ArgentinaFil: Pratta, Guillermo Raúl. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Arce, Debora Pamela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de San Nicolás. - Universidad Tecnológica Nacional. Facultad Regional San Nicolás. Centro de Investigaciones y Transferencia de San Nicolás; Argentin

Structural and functional analysis of two sHSP subfamilies in tomato ripening

The small Heat Shock Proteins (sHSP) gene family shows a high copy number of members, involved in stress and developmental processes in plants. We have studied the genomic structure and function of two sHSP subfamilies on chromosomes 6 and 9 in Solanum lycopersicum cv. Caimanta and S. pimpinellifolium accession LA0722, which are the parental lines of different breeding populations obtained by our research group. A similar tandem genomic arrangement between cv. Caimanta and accession LA0722, compared to the reference tomato genome cv Heinz 1706, has been observed, with 4 and 2 members, respectively. Gene variations having a copy number from 3 to 5 members for these sHSP, were identified in representative exotic tomato species (S. pennelli LA0716 and S. habrochaites LYC4) and the related crop potato. In order to obtain a better understanding of the regulation of both sHSP groups in fruit ripening, transcriptome analysis by RNA-Seq was performed. Differences in gene expression among cv. Caimanta and accession LA0722 were identified, and previously detected interactors were actively expressed for both sHSP clusters. Promoter regions of these sHSP and their interactors had molecular polymorphism with variation on HSE densities. Our results can be used in breeding programs for the design of sequence-based specific molecular markers, enabling a more efficient development of new commercial varieties with desired traits related to sHSP differential expression.Fil: Cacchiarelli, Paolo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Arce, Debora Pamela. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro de Investigaciones y Transferencia de San Nicolas. - Universidad Tecnologica Nacional. Facultad Reg.san Nicolas. Centro de Investigaciones y Transferencia de San Nicolas.; ArgentinaFil: Tapia, Elizabeth. Universidad Nacional de Rosario; ArgentinaFil: Pratta, Guillermo Raúl. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; Argentin

Tandem duplication events in the expansion of the small heat shock protein gene family in solanum lycopersicum (cv. Heinz 1706)

In plants, fruit maturation and oxidative stress can induce small heat shock protein (sHSP) synthesis to maintain cellular homeostasis. Although the tomato reference genome was published in 2012, the actual number and functionality of sHSP genes remain unknown. Using a transcriptomic (RNA-seq) and evolutionary genomic approach, putative sHSP genes in the Solanum lycopersicum (cv. Heinz 1706) genome were investigated. A sHSP gene family of 33 members was established. Remarkably, roughly half of the members of this family can be explained by nine independent tandem duplication events that determined, evolutionarily, their functional fates. Within a mitochondrial class subfamily, only one duplicated member, Solyc08g078700, retained its ancestral chaperone function, while the others, Solyc08g078710 and Solyc08g078720, likely degenerated under neutrality and lack ancestral chaperone function. Functional conservation occurred within a cytosolic class I subfamily, whose four members, Solyc06g076570, Solyc06g076560, Solyc06g076540, and Solyc06g076520, support ~57% of the total sHSP RNAm in the red ripe fruit. Subfunctionalization occurred within a new subfamily, whose two members, Solyc04g082720 and Solyc04g082740, show heterogeneous differential expression profiles during fruit ripening. These findings, involving the birth/death of some genes or the preferential/plastic expression of some others during fruit ripening, highlight the importance of tandem duplication events in the expansion of the sHSP gene family in the tomato genome. Despite its evolutionary diversity, the sHSP gene family in the tomato genome seems to be endowed with a core set of four homeostasis genes: Solyc05g014280, Solyc03g082420, Solyc11g020330, and Solyc06g076560, which appear to provide a baseline protection during both fruit ripening and heat shock stress in different tomato tissues.Fil: Krsticevic, Flavia Jorgelina. Universidad Tecnológica Nacional. Facultad Regional San Nicolás; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas. Universidad Nacional de Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas; ArgentinaFil: Arce, Debora Pamela. Universidad Tecnológica Nacional. Facultad Regional San Nicolás; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias; ArgentinaFil: Ezpeleta, Joaquin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas. Universidad Nacional de Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Exactas, Ingeniería y Agrimensura; ArgentinaFil: Tapia Paredes, Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas. Universidad Nacional de Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Exactas, Ingeniería y Agrimensura; Argentin

The analysis of an Arabidopsis triple knock-down mutant reveals functions for MBF1 genes under oxidative stress conditions

Transcriptional co-activators of the multiprotein bridging factor 1 (MBF1) type belong to a small multigenic family that controls gene expression by connecting transcription factors and the basal transcription machinery. In this report, a triple knock-down mutant (abc-) for the Arabidopsis thaliana MBF1 genes AtMBF1a, AtMBF1b and AtMBF1c was generated. The phenotypic characterization using oxidative agents such as hydrogen peroxide and methyl viologen revealed that the abc- mutant was more sensitive to oxidative stress. The triple knock-down mutant, abc- was also sensitive to osmotic stress mediated by high concentrations of sorbitol. Furthermore, the abc- phenotype was partially or completely rescued by AtMBF1c cDNA over-expression (abc- +c) depending on physiological and developmental conditions. AtMBF1s regulate the expression of ABR1, which is a member of the ethylene-response factor family and acts as ABA repressor. Thus, we conclude that AtMBF1 gene family may function as a regulatory component of the cross-talk node between ethylene, ABA and stress signal pathways. Furthermore, higher levels of a HSP70 mRNA and an immunoreactive HSP70 protein were detected in the abc- mutant. The participation of MBF1c as a possible negative regulator of HSP genes was discussed.Fil: Arce, Debora Pamela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Godoy, Andrea Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Biológicas. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Biológicas; ArgentinaFil: Tsuda, Kenichi. University of Minnesota; Estados UnidosFil: Yamazaki, Ken Ichi. Hokkaido University; JapónFil: Valle, Estela Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Iglesias, María José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Biológicas. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Biológicas; ArgentinaFil: Di Mauro, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Biológicas. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Biológicas; ArgentinaFil: Casalongue, Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Biológicas. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Biológicas; Argentin