4,810 research outputs found
SUMOylation of Rad52-Rad59 synergistically change the outcome of mitotic recombination
Homologous recombination (HR) is essential for maintenance of genome stability through double-strand break (DSB) repair, but at the same time HR can lead to loss of heterozygosity and uncontrolled recombination can be genotoxic. The post-translational modification by SUMO (small ubiquitin-like modifier) has been shown to modulate recombination, but the exact mechanism of this regulation remains unclear. Here we show that SUMOylation stabilizes the interaction between the recombination mediator Rad52 and its paralogue Rad59 in Saccharomyces cerevisiae. Although Rad59 SUMOylation is not required for survival after genotoxic stress, it affects the outcome of recombination to promote conservative DNA repair. In some genetic assays, Rad52 and Rad59 SUMOylation act synergistically. Collectively, our data indicate that the described SUMO modifications affect the balance between conservative and non-conservative mechanisms of HR
Object and Objectivity in Divination
In this article, the author explores basket divination, a technique found in Zambia and neighboring countries, as a form of material religion. Mores specifically, the author shows that in basket divination the idea of objectivity (objective knowledge) is directly associated with the materiality of the oracle used for divining. In the Luvale language spoken in the area, the word employed for the verb knowing shares the same root as the word employed to refer to the divination pieces contained in the oracle
Reification and Fetishism: Processes of Transformation
Reification, fetishism, alienation, mastery, and control – these are some of the key concepts of modernity that have been battered and beaten by postmoderns and nonmoderns alike, with Bruno Latour, a nonmodern, discarding them most recently. Critical of this approach, which creates a rift between moderns and nonmoderns, the author engages in dialogue with modern thinkers – particularly Peter Berger, Thomas Luckmann and Stanley Pullberg – with a view to recycling and redefining the concept of reification from a nonmodern perspective. Marxian scholars associate reification with an attitude of detachment and passivity. The author seeks to convert the negative and asymmetrical Marxian reading of reification, which places subjects above objects, to a positive symmetry. Marx explained the capitalist economy through the lens of religion. Reversing the direction of symmetrical comparison, the author considers the northwestern Zambian universe of ancestors through the lens of Marxian concepts, mainly reification and fetishism. There is much to gain from recycling the old concept of reification. In a non-partisan symmetrical perspective, the redefinition of reification as fetishism yields a new, positive understanding of the place of material and immaterial things in social life and the ways in which we humans apprehend the world and implicate those things in our projects and struggles. Reification is not an impediment to action but a condition for action
Political Evil: Witchcraft from the Perspective of the Bewitched
Instead of asking what evil is, let us see where evil takes us. Based on many conversations on the topic of witchcraft in northwest Zambia, Africa—conversations in which witchcraft is presented from the perspective of the bewitched—the concept of evil takes us to a ghastly realm of destruction and transfiguration where the discourse of morality feels lacking and out of place. This is an ontological realm where humans metamorphose into wild animals, beasts, even monsters. This idea of evil as excess with an ontological weight should be taken a step further: the shift from the moral to the ontological gives rise to highly systematic, often ritualized processes of interpersonal predation, which leads, if not curbed, to suffering and death. In the movement from bad to evil, the process of systematic dehumanization of one by another is unleashed, reducing humans to the conditions of predators and prey. The movement from morality to ontology is also a movement from morality to absolute violence
Mind, Body and Spirit in Basket Divination: An Integrative Way of Knowing
The statements of researchers on the topic of basket divination and the statements of basket diviners in northwest Zambia, Africa, do not fully agree. While researchers rightly stress the importance of observation, analysis and interpretation in basket divination, going so far as to describe diviners as scientists, they fail to recognize that divination is not an abstract, disembodied undertaking. Truthful knowledge is not flushed out of the diviner’s mind as a set of theoretical propositions; it is instead delivered by an ancestral spirit that becomes objectified in three symbiotic forms: physical pain, configurations of material objects laid out inside a basket, and the diviner’s translation of those meaningful configurations into words. In basket divination, human bodies, artifacts, words, and spirits work together in symbiosis. Knowing is a spiritual, intellectual, and embodied undertaking. The challenge then is to conceptualize basket divination as an integrative way of knowing in such a way that one does not fail to recognize either the neurobiological substrate that we all share as humans or those others facets—such as the numen—without which basket divination as a cultural practice would cease to exist
Human mitochondrial degradosome prevents harmful mitochondrial R loops and mitochondrial genome instability
R loops are nucleic acid structures comprising an DNA-RNA hybrid and a displaced single-stranded DNA. These structures may occur transiently during transcription, playing essential biological functions. However, persistent R loops may become pathological as they are important drivers of genome instability and have been associated with human diseases. The mitochondrial degradosome is a functionally conserved complex from bacteria to human mitochondria. It is composed of the ATP-dependent RNA and DNA helicase SUV3 and the PNPase ribonuclease, playing a central role in mitochondrial RNA surveillance and degradation. Here we describe a new role for the mitochondrial degradosome in preventing the accumulation of pathological R loops in the mitochondrial DNA, in addition to preventing dsRNA accumulation. Our data indicate that, similar to the molecular mechanisms acting in the nucleus, RNA surveillance mechanisms in the mitochondria are crucial to maintain its genome integrity by counteracting pathological R-loop accumulation.European Research Council ERC2014 AdG669898 TARLOOPMinisterio de Economía y Competitividad BFU2013-42918-P, BFU2016-75058-
ISOLATION OF A BIOACTIVE PROTEIC FRACTION OF Solanum marginatum
Solanum marginatum belong to the family of Solanaceae, is widely used in traditional Mexican medicine. However, their properties have not been evaluated; so that in this study we tested some biological activities of a protein fraction of S. marginatum. For this, proteins were extracted from S. marginatum leaves, a protein fraction isolated by FPLC, protein content quantified by BCA method, an enzyme activity assay performed by Kunitz method, protein sub-fractions were identified by SDS-PAGE. The ability to capture radicals was determined by the DPPH and ABTS methods. The toxic effect was assessed with the A. salina assay while cell viability in peripheral blood mononuclear cells (PBMC) was tested by MTT method. Isolation of PF-FPLC was carried out at Rt = 2.13 min, further, separated and identified seven subfractions with molecular weights ranging from 18-112 kDa, while the optimal conditions of enzymatic activity were 37 ° C, pH 7 and 120 min. The ABTS and DPPH methods showed a radical capture percentage of 20 and 62 % respectively.PF-FPLC proteins had no toxic effect in A. salina, however, displayed a low antimicrobial effect (inhibition ≤ 35%) as well as an effect on the cellular viability of PBMC
A Pedagogia Freinetiana e as vivências no Programa Mais Educação na oficina do Jornal escolar.
Determinants of working capital management
This paper analyzes the determinants of working capital management (WCM) for a sample of Spanish firms during the period 1997-2004. We find that firms have a target investment in working capital and that they take decisions in order to achieve this. The results appear to support the hypothesis that the working capital competes with investment in fixed assets for the funds of the firms when they have financial constraints. Finally, we also find that WCM depends on bargaining power and other financial factors such as the availability of internal finance, cost of financing and financial constraints.Research Agency of the Spanish Government ECO2008-06179/ECO
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