Cdk1, Plks, Auroras, and Neks: the mitotic bodyguards.

In: Li JJ, Li SA, Mohla S, Rochefort H, Maudelonde T, (eds), 2008, Hormonal Carcinogenesis V : Proceedings of the Fifth International Symposium, New York, Springer-Verlag. (Adv. Exp. Med. Biol. 617)International audienceThe coordination of progression through mitosis is mainly orchestrated by protein phosphorylation insured by several serine/threonine kinases. In this short review we will focus on the four main mitotic kinase families: the cyclin-dependent kinase: Cdks, the polo-like kinases: Plks, the Aurora kinases and the NIMArelated kinases: Nerks

En finit elementmodell av bi-stabila tejp-fjädrar av vävda kompositer.

The recent development of CubeSat nano-satellites shows that it is an effective way to send a payload onto orbit, as it is a relatively inexpensive and quick access to space. If the small size of these satellites is their main advantage, it is also the principal source of problems when it comes to designing it. The control electronics, electric power system and the payload are limited in mass and have to t in a tiny ten-centimeter cube. The necessity of a compact deployable structure to hold the payload once the satellite reached its orbit is one of the principal subject of study for the design of a CubeSat. In the CubeSat program SWIM (Space Weather using Ion Spectrometers and Magnetometers) that KTH takes part in, the  deployablestructure developed consists of bi-stable semi-tubular booms made by a woven-composite fabric. Preliminary tests show that this structure is very compact and stable in the packaged con guration while being suciently long and stiin the deployed con guration. However little is known about the deployment phase, the physical model of the booms is very inaccurate in determining the deployment force and speed, because of the complexity of the material mechanics behind it. Modeling a woven composite material in a nite element analysis software is a dicult task due the structure of the material itself. The ber yarns interlace each other like in textile material, and they are impregnated in a soft matrix resin. Although in-plane properties of these materials can be calculated accurately using the classic lamination theory (CLT), the corresponding out-of-plane properties lack any accuracy for one-ply woven composites. Solutions are found through micromechanical approaches but these models are dicult to implement and are computationally expensive. The solution to this problem is to decline the CLT model of the material in two versions, each with a its own purpose. This paper presents rst a CLT model of the woven composite which aim is to predict in-plane properties accurately and giving a good estimation of the out-of-plane properties. The second version of the CLT model is developed with the aim of predicting accurately the amount of strain energy stored and the stable radius of the rolled-up con guration. The purpose of this version is to be used in deployment analysis. This paper also presents the main lines of a fully parameterized nite element model of the deployment analysis for future use

A classical lamination model of bi-stable woven composite tape-springs

This extended abstract presents the work done so far on modeling woven composite materials, specifically two carbon fiber reinforced plastics materials: twill and plain weave. The material model has been initially verified against data available in a database.QC 2012021

Tactic : A New Detector for Nuclear Astrophysics

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Guide d’utilisation de l’exécutable QrCodeGenerator

L’exécutable QrCodeGenrator permet la génération de codes de traçabilité et leur impression sur des étiquettes autocollantes. L’exécutable est conçu pour répondre en premier lieu au besoin Obsbio. A savoir un code de traçabilité unique faisant référence aux lignes de plan Imagine (https://doi.org/10.13155/86111). L’utilisation d’un code de traçabilité devient primordial dans la vie de la donnée et des échantillons biologiques. Cet outil s’inscrit totalement dans l’objectif du projet SI MORSE (Marine Oganisms and Ressources and Storage systEm) dont l’objectif est de tracer tous les échantillons biologiques non détruits (https://w3z.ifremer.fr/morse/ ). Le code de traçabilité a pour objectif de tracer tous les échantillons depuis leur prélèvement, leur traitement, jusqu’à leur archivage. Ces actions viennent compléter les dispositifs déjà en place tel que l’utilisation du module workflow dans Labcollector pour le suivi des lots de pièces calcifiées (https://archimer.ifremer.fr/doc/00116/22764/)

Exploiting rhizosphere microbial cooperation for developing sustainable agriculture strategies

International audienc

Mnk1 kinase activity is required for abscission.

International audienceMnk1 is a serine/threonine kinase identified as a target for MAP kinase pathways. Using chemical drug, kinase-dead expression or knock down by RNA interference, we show that inhibition of Mnk1 induces the formation of multinucleated cells, which can be rescued by expressing an RNA interference resistant form of Mnk1. We found that active human Mnk1 localises to centrosomes, spindle microtubules and the midbody. Time-lapse recording of Mnk1 depleted cells display cytokinesis defects, as daughter cells fuse back together. Under inhibition of Mnk1 activity, no microtubule defect at the midbody was detected, however membrane vesicles anchorage at the midbody was impaired as lumenal-GFP positive-vesicles did not accumulate at the midbody. At the molecular level, we found that centriolin localisation was impaired at the midbody in Mnk1 depleted cells. As a consequence endobrevin, a V-SNARE protein implicated in the abscission step, was not properly localised at the midbody. Altogether our data show that Mnk1 activity is required for abscission

Localization of aurora A and aurora B kinases during interphase: role of the N-terminal domain.: Interphase localization of Aurora kinases A and B

International audienceAurora kinases possess a conserved catalytic domain (CD) and a N-terminal domain (ND) that varies in size and sequence. We have previously reported that the N-terminal domain of AuroraA (AurA) participates in the localization of the kinase to the centrosome in interphase. AuroraB (AurB) is a chromosome passenger protein and its N-terminal domain is not necessary for its localization or function during mitosis. Using various combinations of GFP-AurA and AurB protein domains we show that AurB N-terminal domain is required for nuclear localization in Xenopus XL2 cells in interphase. In human cells, however, we found both AurA and AurB kinases in the nucleus, AurA being mainly cytoplasmic and AurB mainly nuclear. Both proteins are actively excluded from the nucleus by a CRM1 dependent pathway. Interestingly, at a functional level, in interphase, every combination of Aurora kinase domains (ND-CD) rescues histone H3 Serine10 phosphorylation defect induced by AurB knockdown. This clearly indicates the presence of a functional AurA in the nucleus. However, the chimera ND-AurA/CD-AurB was much more efficient than the ND-AurB/ CD-AurA to rescue multinucleation also induced by AurB knockdown. This indicates that the catalytic domain of AurB is required to fulfill specific functions during mitosis that cannot be fulfilled by the catalytic domain of AurA, probably for localization reasons during mitosis

Does in vitro selection of biocontrol agents guarantee success in planta? A study case of wheat protection against Fusarium seedling blight by soil bacteria

International audienceBiological control is a great hope for reducing the overutilization of pesticides in agricultural soils. It often involves microorganisms or molecules produced by microorganisms that will be able to interact with either a plant or pathogens of this plant to reduce the growth of the pathogen and limit its negative impact on the host plant. When new biocontrol products are developed, strains were mostly selected based on their ability to inhibit a pathogen of interest under in vitro conditions via antagonistic effects. Strains with no in vitro effect are often discarded and not tested in planta. But is the in vitro selection of bacterial agents according to their antagonism activities towards a plant pathogen the best way to get effective biocontrol products? To answer this question, we used wheat and the fungal pathogen Fusarium graminearum as a study pathosystem model. A library of 205 soil bacteria was screened in 2 types of in vitro growth inhibition tests against F. graminearum, and in an in planta experiment. We find strains which do not have inhibition phenotypes in vitro but good efficacy in planta. Interestingly, some strains belong to species (Microbacterium, Arthrobacter, Variovorax) that are not known in the literature for their ability to protect plants against fungal pathogens. Thus, developing a biocontrol product against F. graminearum must be preferentially based on the direct screening of strains for their protective activity on wheat plants against fungal diseases, rather than on their in vitro antagonistic effects on fungal growth