Thomas Masaryk, Viennois ou Pragois ?

Tomás Garrigue Masaryk (1850-1937) fut le fondateur et le premier président de la République tchécoslovaque (1918-1935). Mais il est peu connu qu’avant 1914, il séjourna une quinzaine d’années de sa vie à Vienne, pour ses études, pour son premier poste universitaire puis comme député au Reichsrat. Président tchécoslovaque, il n’oublia pas cette longue fréquentation de Vienne, au point que dans son pays, il en paraissait suspect malgré sa popularité. Masaryk œuvra pour la réconciliation entre Prague et Vienne.Tomás Garrigue Masaryk (1850-1937) war Mitbegründer und erster Staatspräsident der Tschechoslowakischen Republik (1918-1935). Dass er vor 1914 zuerst als Student, dann als Universitätsdozent und Reichstagsabgeordneter ca. fünfzehn Jahre in Wien verbrachte, ist aber weniger bekannt. Als tschechoslowakischer Präsident vergaß er diese Wiener Jahre nicht, so dass er trotz der großen Popularität, die er in seiner Heimat genoss, als etwas verdächtig erscheinen konnte. Masaryk setzte sich für eine Aussöhnung zwischen Prag und Wien ein.Tomás Garrigue Masaryk (1850-1937) was the founder and first president of the Czechoslovak Republic (1918-1935). However, it is less known that he spent about fifteen years in Vienna as a student, as a young university teacher and as a member of the Reichsrat. As the President of Czechoslovakia, he never forgot these years in Vienna, and therefore he was considered to be suspicious by some of his compatriots in spite of his popularity. Masaryk acted as a go-between, trying to reconcile Prague and Vienna

Le Léon dans la Bretagne des X e -XI e siècles (Kemenet et vicomté)

L’histoire du Léon s’inscrit, de la fin des invasions normandes, vers 936, jusqu’à la première Croisade, en 1096, dans celle du duché de Bretagne. Le fief de Kemenet-Ily, en Léon, fut l’un des sept Kemenet (en incluant la vicomté de Poudouvre) recensés en Bretagne. Ce mot, désignant en langue bretonne un fief donné à un baron, était déjà cité dans les actes dès la première moitié du XIe siècle. On peut penser qu’ils furent créés par le duc Alain Barbetorte, vers le milieu du Xe siècle, afin de restaurer la principauté bretonne, et que certains eurent à leur tête des vicomtes, comme le Kemenet de Cornouaille et le Kemenet-Ily. L’étude cherche à identifier leurs descendants dans des lignages qui portaient encore le titre, devenu honorifique, de vicomte, jusqu’au XVe siècle. Puis, des lignages plus puissants s’imposèrent au XIe siècle. Ainsi, la maison vicomtale de Léon, dont les origines seraient cornouaillaises, supplanta l’aristocratie léonarde (« primates leonenses »). Ils édifièrent la forteresse de la Roche-Morvan et renforcèrent les cités de Lesneven, en Kemenet-Ily, puis de Brest et de Morlaix, cette dernière devenant le centre de leur pouvoir jusqu’à la fin du XIIe siècle.The history of Léon was linked to that of the duchy of Brittany, from the end of Norman invasions (in about 936) up to the first crusade in 1096. The lordship of Kemenet-Ily, in Léon, was one of the seven known Kemenet (including the viscountcy of Poudouvre) in Brittany. A Kemenet was a territory given to a baron, and the word was already employed in deeds in the first half of the eleventh century. They were probably created by Duke Alain Barbetorte in the middle of the tenth century to strengthen the principality of Brittany. Some of their lords were viscounts, as was the case for the Kemenet of Cornouaille and Kement-Ily. This study tries to identify their descendants in lines that bore the title of viscount up to the fifteenth century. Then, more powerful lineages took control during the eleventh century. Thus, the house of the viscounts of Léon, which probably came from Cornouaille, replaced the local aristocracy (the “primates leonenses”). They built the castle of La Roche Morvan and reinforced the city of Lesneven, in Kemenet-Ily, and later those of Brest and Morlaix, the latter town becoming the centre of their power up to the end of twelfth century

Recherches sur les origines du Kemenet de Cornouaille (ixe-xie siècles)

La présente étude, qui prolonge un précédent travail sur les origines des vicomtes de Léon au xie siècle, tente de rechercher en Cornouaille les racines de ce lignage dans le Kemenet, l’un de leurs principaux fiefs. Cette seigneurie, qui s’étendait entre l’Odet et l’océan et jusqu’à la Montagne de Locronan, était limitrophe de la baronnie du Pont et d’un fief appartenant aux comtes de Cornouaille, au sud. On peut envisager l’hypothèse du démembrement en trois seigneuries principales d’un fief originel couvrant le Cap Caval. Désignant un territoire attribué à un vassal, le terme Kemenet n’est apparu qu’après les invasions normandes : le premier titulaire pourrait en être Dilès, vicomte d’Alain Barbetorte, à la fin du xe siècle. Le souvenir du vicomte Guiomarch, dont l’existence est attestée au milieu du xie siècle par des actes du cartulaire de l’abbaye de Quimperlé, pourrait s’être conservé dans une version de la légende du roi March, collectée près de Quimper à Penhars, siège du Kemenet, et connue en d’autres lieux de Cornouaille occidentale. En outre, des présomptions existent en faveur d’une alliance ancienne, voire d’une origine commune, entre les seigneurs du Kemenet et les sires de Pont-L’Abbé. Enfin, l’extension du Kemenet jusqu’aux confins de Locronan et les incertitudes sur l’identité des donateurs du minihi de saint Ronan découlant de la charte apocryphe de l’abbaye de Quimperlé, dite de « Guet Ronan », nous conduisent à proposer un lien entre cette donation et la défaite du vicomte Guiomarch face aux troupes du comte de Cornouaille, Alain Canhiart, relatée dans un autre acte du cartulaire de cette abbaye. L’histoire du Kemenet, au xie siècle, serait ainsi liée à celle d’un lignage cornouaillais, dont seraient issus les vicomtes de Léon.The present study which follows a preceding work about origins of Viscount of Léon during 11h Century tries to search in Britannic Kernow roots of this ancient line in Kemenet, one of their main lordships. This one, spreading between Odet’s river, ocean and Locronan’s mountain, was bordering two others: that of Baron of Pont-L’Abbé and that of Kernow Count. We can think that an original lordship, which was spreading on Cap-Caval, had been dismembered in three ones. Word “Kemenet”, meaning in Breton language a territory given to a baron, appeared after Norman invasions: first Kemenet lord could have been Dilès, viscount of Alan Barbetorte, in the end of 10th Century. Memory of Viscount Guiomarch, who is known by charters of middle of 11th Century from Quimperlé Abbe, could have be preserved in a version of king March’s legend collected near Quimper, at Penhars, see of Kemenet, and in others places of West Kernow. Also, some presumptions can be found in favour of ancient alliance, or even common origins, between lords of Kemenet and lords of Pont-L’Abbé. Finally, the extension of Kemenet up to limits of Locronan and the doubts about identity of “minihi sancti Ronani” donors suggested by a spurious charter from Quimperlé Abbey (called “Guet Ronan”) induce a link between this donation and Viscount Guiomarch’s defeat against Alain Canhiart, Count of Kernow, related by another charter from the same abbey. History of Kemenet during 11th Century should then be linked to this of a Kernow line, from which should be descended Viscounts of Léon

Live imaging of DORNRÖSCHEN and DORNRÖSCHEN-LIKE promoter activity reveals dynamic changes in cell identity at the microcallus surface of Arabidopsis embryonic suspensions

Key message Transgenic DRN::erGFP and DRNL::erGFP reporters access the window from explanting Arabidopsis embryos to callus formation and provide evidence for the acquisition of shoot meristem cell fates at the microcalli surface. Abstract The DORNRÖSCHEN (DRN) and DORNRÖSCHEN-LIKE (DRNL) genes encode AP2-type transcription factors, which are activated shortly after fertilisation in the zygotic Arabidopsis embryo. We have monitored established transgenic DRN::erGFP and DRNL::erGFP reporter lines using live imaging, for expression in embryonic suspension cultures and our data show that transgenic fluorophore markers are suitable to resolve dynamic changes of cellular identity at the surface of microcalli and enable fluorescence-activated cell sorting. Although DRN::erGFP and DRNL::erGFP are both activated in surface cells, their promoter activity marks different cell identities based on real-time PCR experiments and whole transcriptome microarray data. These transcriptome analyses provide no evidence for the maintenance of embryogenic identity under callus-inducing high-auxin tissue culture conditions but are compatible with the acquisition of shoot meristem cell fates at the surface of suspension calli

The ribosome-associated chaperone Zuo1 controls translation upon TORC1 inhibition

Protein requirements of eukaryotic cells are ensured by proteostasis, which is mediated by tight control of TORC1 activity. Upon TORC1 inhibition, protein degradation is increased and protein synthesis is reduced through inhibition of translation initiation to maintain cell viability. Here, we show that the ribosome-associated complex (RAC)/Ssb chaperone system, composed of the HSP70 chaperone Ssb and its HSP40 co-chaperone Zuo1, is required to maintain proteostasis and cell viability under TORC1 inhibition in Saccharomyces cerevisiae. In the absence of Zuo1, translation does not decrease in response to the loss of TORC1 activity. A functional interaction between Zuo1 and Ssb is required for proper translational control and proteostasis maintenance upon TORC1 inhibition. Furthermore, we have shown that the rapid degradation of eIF4G following TORC1 inhibition is mediated by autophagy and is prevented in zuo1Δ cells, contributing to decreased survival in these conditions. We found that autophagy is defective in zuo1Δ cells, which impedes eIF4G degradation upon TORC1 inhibition. Our findings identify an essential role for RAC/Ssb in regulating translation in response to changes in TORC1 signalling.</p

BUB-1 and CENP-C recruit PLK-1 to control chromosome alignment and segregation during meiosis I in C. elegans oocytes

Phosphorylation is a key post-translational modification that is utilised in many biological processes for the rapid and reversible regulation of protein localisation and activity. Polo-like kinase 1 (PLK-1) is essential for both mitotic and meiotic cell divisions, with key functions being conserved in eukaryotes. The roles and regulation of PLK-1 during mitosis have been well characterised. However, the discrete roles and regulation of PLK-1 during meiosis have remained obscure. Here, we used Caenorhabditis elegans (C. elegans) oocytes to show that PLK-1 plays distinct roles in meiotic spindle assembly and/or stability, chromosome alignment and segregation, and polar body extrusion during meiosis I. Furthermore, by a combination of live imaging and biochemical analysis we identified the chromosomal recruitment mechanisms of PLK-1 during C. elegans oocyte meiosis. The spindle assembly checkpoint kinase BUB-1 directly recruits PLK-1 to the kinetochore and midbivalent while the chromosome arm population of PLK-1 depends on a direct interaction with the centromeric-associated protein CENP-CHCP-4. We found that perturbing both BUB-1 and CENP-CHCP-4 recruitment of PLK-1 leads to severe meiotic defects, resulting in highly aneuploid oocytes. Overall, our results shed light on the roles played by PLK-1 during oocyte meiosis and provide a mechanistic understanding of PLK-1 targeting to meiotic chromosomes.</p

Cell wall biogenesis of Arabidopsis thaliana elongating cells: transcriptomics complements proteomics

<p>Abstract</p> <p>Background</p> <p>Plant growth is a complex process involving cell division and elongation. <it>Arabidopsis thaliana </it>hypocotyls undergo a 100-fold length increase mainly by cell elongation. Cell enlargement implicates significant changes in the composition and structure of the cell wall. In order to understand cell wall biogenesis during cell elongation, mRNA profiling was made on half- (active elongation) and fully-grown (after growth arrest) etiolated hypocotyls.</p> <p>Results</p> <p>Transcriptomic analysis was focused on two sets of genes. The first set of 856 genes named cell wall genes (CWGs) included genes known to be involved in cell wall biogenesis. A significant proportion of them has detectable levels of transcripts (55.5%), suggesting that these processes are important throughout hypocotyl elongation and after growth arrest. Genes encoding proteins involved in substrate generation or in synthesis of polysaccharides, and extracellular proteins were found to have high transcript levels. A second set of 2927 genes labeled secretory pathway genes (SPGs) was studied to search for new genes encoding secreted proteins possibly involved in wall expansion. Based on transcript level, 433 genes were selected. Genes not known to be involved in cell elongation were found to have high levels of transcripts. Encoded proteins were proteases, protease inhibitors, proteins with interacting domains, and proteins involved in lipid metabolism. In addition, 125 of them encoded proteins with yet unknown function. Finally, comparison with results of a cell wall proteomic study on the same material revealed that 48 out of the 137 identified proteins were products of the genes having high or moderate level of transcripts. About 15% of the genes encoding proteins identified by proteomics showed levels of transcripts below background.</p> <p>Conclusion</p> <p>Members of known multigenic families involved in cell wall biogenesis, and new genes that might participate in cell elongation were identified. Significant differences were shown in the expression of such genes in half- and fully-grown hypocotyls. No clear correlation was found between the abundance of transcripts (transcriptomic data) and the presence of the proteins (proteomic data) demonstrating (i) the importance of post-transcriptional events for the regulation of genes during cell elongation and (ii) that transcriptomic and proteomic data are complementary.</p