Single-molecule Dynamics in Protein Interactions: Characterization of RarA and RecD2 of Bacillus subtilis

Maintenance of genome integrity is one of the crucial functions in life, to preserve the appropriate genetic information, being homologous recombination a key process in the DNA repair. I have used a novel technique, using slim-field microscopy to obtain single-molecule dynamics of two poorly described proteins, RarA and RecD2, in different recombination deficient mutants and conditions to characterize them. Single-molecule microscopy has been shown as a powerful method for in vivo characterization of proteins and its interactions. Together with genetics, I have added a new level of complexity in the regulation of homologous recombination as a multiway process in which many factors are involved in different avenues with partially overlapping functions depending on the kind of DNA damage generated. I have characterized RarA and RecD2 as factors involved in recombination, but also in replication of the DNA, being part of both RecA-independent and RecA-dependent replication progression, and antagonistic regulators of RecA filamentation. RarA plays its role in replication through interactions with DnaB, and in recombination as a RecA positive regulator through its interactions with RecA, RecO, RecR, RecD2 and RecU. RarA is regulated by the RecQ-like helicases RecQ and RecS. RecD2 plays a role in chromosomal segregation that becomes essential in the absence of RecG or RuvAB, and is a negative regulator in homologous recombination that interacts with RecA, RarA, RecX, RecF and PcrA

Unidad similar en la construcción de la multiplicación: una mirada a los elementos

En este artículo se resalta la existencia de la unidad similar propuesta en Confrey (1994) en el tratamiento que de las magnitudes hace Euclides en los Elementos. La proporción, la tercera y la cuarta proporcional, la extrema y media razón, así como los gnomones son objetos matemáticos que, en relación mutua en la actividad matemática euclidea, se proporcionan significado. El uso iterativo de la unidad similar potencia la construcción de figuras, como en el caso del pentágono, de secuencias potencialmente convergentes de figuras y magnitudes así como la generación de bases posicionales de representación

Medicinal plants utilized by farmers from the neighboring area of the Reserva de Biósfera Yabotí (Misiones, Argentina)

Se presentan los resultados de un estudio etnobotánico de las plantas medicinales utilizadas por pequeños agricultores de un sector del área de influencia de la Reserva de Biósfera Yabotí. Se efectuaron 65 entrevistas semi-estructuradas a hombres y mujeres de distinta edad. El número de especies medicinales relevadas alcanza un total de 176 plantas vasculares, de las cuales 78 son cultivadas y 93 se recolectan en su estado silvestre de distintas situaciones de vegetación. Solamente 5 especies medicinales mencionadas son obtenidas del mercado. Las especies cultivadas y espontáneas son muy similares en cuanto a riqueza, frecuencia de mención y diversidad expresada por medio del índice de ShannonThe results of a ethnobotanical study of the medicinal plants used by small farmers near to the Reserva de Biósfera Yabotí, are presented. Sixty-five semi structured interviews were made to men and women of different age. The number of medicinal species reaches the 176 vascular plants, of which 78 are cultivated and 93 are gathered in its wild state. Only five medicinal species are obtained of the market. The cultivated and spontaneous species are very similar as for richness, mention frequency and diversity expressed by Shannon index (H’)Fil: Keller, Hector Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Romero, Héctor F.. Universidad Nacional de Misiones; Argentin

Camellia sinensis (Theaceae) en la Argentina : naturalización y usos locales

Sobre la base de ejemplares recolectados en las provincias de Misiones y Corrientes (Argentina) se cita por primera vez al té como una especie naturalizada en el país. La especie es descripta e ilustrada y además se dan a conocer sus usos locales.Camellia sinensis (Theaceae) in Argentina: Naturalization and local uses. By means of herbarium specimens collected in Misiones and Corrientes provinces (Argentina), the tea is mentioned for the first time as a naturalized plant in our country. The species is described and illustrated. Local uses of this species are also mentioned.Fil: Keller, Hector Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Nordeste. Instituto de Botánica del Nordeste (i); ArgentinaFil: Delucchi, Gustavo. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo; ArgentinaFil: Romero, Héctor F.. Universidad Nacional de Misiones. Facultad de Ciencias Forestales; Argentin

Single-molecule Dynamics in Protein Interactions: Characterization of RarA and RecD2 of Bacillus subtilis

Maintenance of genome integrity is one of the crucial functions in life, to preserve the appropriate genetic information, being homologous recombination a key process in the DNA repair. I have used a novel technique, using slim-field microscopy to obtain single-molecule dynamics of two poorly described proteins, RarA and RecD2, in different recombination deficient mutants and conditions to characterize them. Single-molecule microscopy has been shown as a powerful method for in vivo characterization of proteins and its interactions. Together with genetics, I have added a new level of complexity in the regulation of homologous recombination as a multiway process in which many factors are involved in different avenues with partially overlapping functions depending on the kind of DNA damage generated. I have characterized RarA and RecD2 as factors involved in recombination, but also in replication of the DNA, being part of both RecA-independent and RecA-dependent replication progression, and antagonistic regulators of RecA filamentation. RarA plays its role in replication through interactions with DnaB, and in recombination as a RecA positive regulator through its interactions with RecA, RecO, RecR, RecD2 and RecU. RarA is regulated by the RecQ-like helicases RecQ and RecS. RecD2 plays a role in chromosomal segregation that becomes essential in the absence of RecG or RuvAB, and is a negative regulator in homologous recombination that interacts with RecA, RarA, RecX, RecF and PcrA

Relative stability of ordered phases in bcc Cu-Al-Zn

The relative stability of the short range ordered and different long range ordered structures in body centered cubic CuAlZn is studied by means of the Cluster Variation Method in the Irregular Tetrahedron approximation (IT-CVM). The energetic parameters (constant pair interchange energies for first and second neighbor pairs) used in our calculations have been extracted from experimental orderdisorder transition temperatures. It is shown that the use of constant pair interchange energies allows accurate reproduction of the experimental transition temperatures in the binary subsystems CuAl and CuZn. Several isothermal sections of the ternary system at temperatures between 600 and 900 K have been calculated. The two-phase field for compositions around Cu3Al in the ternary system was determined: It was found that such region extends to around 15 at.% Zn in the pseudo-binary Cu 0.760.5xAl0.240.5xZnx.Fil: Lanzini, Fernando Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Física de Materiales; ArgentinaFil: Romero, R.. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Física de Materiales; ArgentinaFil: Rubiolo, Gerardo Hector. Universidad Nacional de San Martín. Instituto Sabato; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Interdisciplinariedad y Ciencias Humanas

Este artículo quiere ilustrar la problemática del método interdisciplinario en los estudios sociales, teniendo como principal referencia los discursos de los grandes autores del mundo que se han interesado en esta materia