Genomic DNA PCR analysis to assess xenograft development in mouse mammary gland

The mouse transplantation model remains the most relevant methodology to assess the functional capacities of mammary cells and is particularly appropriate for investigations regarding mammary stem cells, whatever the species studied. Following xenotransplantation in mice mammary fat pad, the development of the xenograft is commonly evaluated by immunohistology. Here, we present a simple and rapid method to control the species specificity of a xenograft based on genomic DNA PCR amplification. DNA is extracted from the fixed samples intended for histology, thus allowing the reuse of precious samples. Standard and digital droplet PCR (requiring low DNA quantities) methods have been used to make the present method suitable for the analysis of xenotransplanted samples

Liberalisation, surveillance and suicide at La Poste

This article examines how the contradictory dynamics of freedom and control that characterise neoliberal capitalism are played out on lived experiences of work in the context of the newly liberalised and restructured French postal services (La Poste). At La Poste, liberalisation was framed as a great emancipatory project that would reinvigorate a moribund state-owned company, remove regulatory constraints, deepen economic freedoms and strip away deadening bureaucracy. Yet, whilst liberalisation freed La Poste of regulatory controls, it was accompanied by an intensified surveillance and control of everyday working life. The new control measures were not limited to external working practices and structures, but sought to capture the individual worker’s personality, communication and values and harness them towards the company’s redefined commercial goals. Drawing on critical scholarship on neoliberal capitalism and labour, the article shows that when capitalist rationality extends beyond working activity and encroaches on complex, intimate and vulnerable dimensions of the person, this can have dangerous human consequences. At La Poste, liberalisation triggered a profound crisis across the company, transforming it into an ‘entreprise en souffrance’ characterised by escalating levels of psychological distress, chronic stress and a series of employee suicides

Structural basis of RNA polymerase III transcription initiation.

RNA polymerase (Pol) III transcribes essential non-coding RNAs, including the entire pool of transfer RNAs, the 5S ribosomal RNA and the U6 spliceosomal RNA, and is often deregulated in cancer cells. The initiation of gene transcription by Pol III requires the activity of the transcription factor TFIIIB to form a transcriptionally active Pol III preinitiation complex (PIC). Here we present electron microscopy reconstructions of Pol III PICs at 3.4-4.0 Å and a reconstruction of unbound apo-Pol III at 3.1 Å. TFIIIB fully encircles the DNA and restructures Pol III. In particular, binding of the TFIIIB subunit Bdp1 rearranges the Pol III-specific subunits C37 and C34, thereby promoting DNA opening. The unwound DNA directly contacts both sides of the Pol III cleft. Topologically, the Pol III PIC resembles the Pol II PIC, whereas the Pol I PIC is more divergent. The structures presented unravel the molecular mechanisms underlying the first steps of Pol III transcription and also the general conserved mechanisms of gene transcription initiation

L'artisanat du textile à Pompéi au Ier siècle après J.-C.

79 après J.-C. : le temps s’arrête à Pompéi. Quelques heures suffisent à figer l’activité humaine sous plusieurs mètres de cendres qui assureront la parfaite conservation des vestiges pour les siècles à venir. Bien représentée au travers des éléments d’architecture encore en place dans la ville (ateliers de teinture, fullonicae), par les peintures et les textes, la production textile occupait une place importante dans l’économie urbaine. Une campagne d’étude menée durant trois ans débouche ici sur une réflexion approfondie à propos de cet artisanat. Elle se fonde sur l’analyse d’une remarquable collection de tissus, en grande partie inédite. Plus de deux cents pièces, diverses et exceptionnellement conservées, ont été systématiquement étudiées du point de vue des techniques et des matériaux. Les procédés de fabrication et la qualité des réalisations ne sont pleinement appréciables que par une analyse et une relecture critique de tous les instruments nécessaires au travail du textile. Cet axe de recherche remet ainsi en perspective les textiles et les outils de production. Indissociables et complémentaires, les fusaïoles, fuseaux, quenouilles, pesons de tisserand, peignes, grilles de tissage sont pris en considération individuellement ou en série selon la richesse des collections. L’acte technique du travailleur du textile, significatif en termes d’innovation, de tradition et de savoir-faire, nous fait entrer dans l’organisation de la production, dans l’économie, dans la société et dans la culture des artisans. Au-delà des nécessaires descriptions techniques, ce livre tente une approche socio-économique de l’activité textile au sein de la cité de Pompéi

Spatial behaviour of free ranging red deer hind (Cervus elaphus) after a 15 months parking period

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Functions and regulation of the Nox family in the filamentous fungus Podospora anserina: a new role in cellulose degradation.

International audienceNADPH oxidases are enzymes that produce reactive oxygen species. Studies in mammals, plants and fungi have shown that they play important roles in differentiation, defence, host/pathogen interaction and mutualistic symbiosis. In this paper, we have identified a Podospora anserina mutant strain impaired for processes controlled by PaNox1 and PaNox2, the two Nox isoforms characterized in this model ascomycete. We show that the gene mutated is PaNoxR, the homologue of the gene encoding the regulatory subunit p67(phox), conserved in mammals and fungi, and that PaNoxR regulates both PaNox1 and PaNox2. Genome sequence analysis of P. anserina reveals that this fungus posses a third Nox isoform, PaNox3, related to human Nox5/Duox and plant Rboh. We have generated a knock-out mutant of PaNox3 and report that PaNox3 plays a minor role in P. anserina, if any. We show that PaNox1 and PaNox2 play antagonist roles in cellulose degradation. Finally, we report for the first time that a saprobic fungus, P. anserina, develops special cell structures dedicated to breach and to exploit a solid cellulosic substrate, cellophane. Importantly, as for similar structures present in some plant pathogens, their proper differentiation requires PaNox1, PaNox2, PaNoxR and the tetraspanin PaPls1

Absence of hyperplasia in Gasp-1 overexpressing mice is dependent on myostatin up-regulation

Background/Aims: Overexpression of Gasp-1, an inhibitor of myostatin, leads to a hypermuscular phenotype due to hypertrophy rather than hyperplasia in mice. However to date, the cellular and molecular mechanisms underlying this phenotype are not investigated. Methods: Skeletal muscles of overexpressing Gasp-1 mice, called Tg(Gasp-1) mice, were analyzed by histological methods. Satellite cell-derived myoblasts from these mice were used to investigate the molecular mechanisms. Results: We demonstrated that hypertrophy in Tg(Gasp-1) mice was related to a myonuclear accretion during the first 3 postnatal weeks and an activation of the pro-hypertrophic Akt/mTORC/p70S6K signaling. In accordance with these results, we showed that overexpressing Gasp-1 primary myoblasts proliferated faster and myonuclei average per myotube was increased during differentiation. Molecular analysis revealed that Gasp-1 overexpression resulted in increased myostatin expression related to its auto-regulation. Despite its inhibition, myostatin led to Pax7 deregulation through its non-canonical Erk1/2 signaling pathway. Consistent with this, inhibition of Erk1/2 signaling pathway as well as neutralization of secreted myostatin rescue the Pax7 expression in overexpressing Gasp-1 myoblasts. Conclusion: Our study shows that myostatin is able to act independently of its canonical pathway to regulate the Pax7 expression. Altogether, our results indicate that myostatin could regulate muscle development despite its protein inhibition

Dare to be resilient: the key to future pesticide-free orchards?

International audienceIn a context of urgent need for a more sustainable fruit tree production, it's high time to find durable alternatives to the systematic use of phytosanitary products in orchards. To this aim, resilience can deliver a number of benefits. Relying on a combination of tolerance, resistance and recovery traits, disease resilience appears as a corner stone to cope with the multiple pest and disease challenge over the orchard’s lifetime. Here, we propose to describe resilience as the capacity of a tree to be minimally affected by external disturbances or to rapidly bounce back to normal functioning after being exposed to these disturbances. Based on a literature survey largely inspired from research on livestock, we highlight different approaches for dissecting resilience phenotypic and genotypic components. In particular, multisite experimental designs and longitudinal measures of so-called ‘resilience biomarkers’ are required. We identified a list of promising biomarkers relying on eco-physiological and digital measurements. Recent advances in high-throughput phenotyping and genomics tools will likely facilitate the fine and temporal monitoring of tree health, allowing to identify resilient genotypes with the calculation of specific resilience indicators. Although resilience can appear as ‘black box’ trait, we demonstrate how it could become a realistic breeding goal