Temperature-dependent transport measurements with Arduino

The current performances of single-board microcontrollers render them attractive, not only for basic applications, but also for more elaborate projects, amongst which are physics teaching or research. In this article, we show how temperature-dependent transport measurements can be performed by using an Arduino board, from cryogenic temperatures up to room temperature or above. We focus on two of the main issues for this type of experiments: the determination of the sample temperature and the measurement of its resistance. We also detail two student-led experiments: evidencing the magnetocaloric effect in Gadolinium and measuring the resistive transition of a high critical temperature superconductor

Plant Transformation Technologies II-February 19-22, 2011 Vienna Austria Presentation : Introduction of a 50 Kb intact DNA fragmentinto wheat genome by biolistic technology

Introduction of a 50 Kb Intact DNA Fragment in Wheat Genome Using Biolistic TechnologyGenetic transformation is a powerful tool for studying gene function and regulation of physiological and developmental processes in plants. Although wheat was the last of the major cereal to be transformed, the introduction and expression of transgene in this plant is now quite feasible.Nowadays another challenge in plant transformation technology is the introduction and stable integration of large intact DNA fragments in plant genome. It would make possible the study in one transformation step of multigenic traits or to study the expression of plant gene in their native genomic context. Recently, it has been shown that expression and regulation of a gene frequently require regulatory elements that could be very distantIn the present study we developed a technology, based on biolistic with dephosphorylated cassettes allowing introduction of a 50 kb intact insert DNA in wheat genome. We have chosen Arabidopsis thaliana DNA as large insert fragments to make easier insert detection, and we have flanked the insert by two reporter genes in order to facilitate screening of plants containing the entire cassette.We have first demonstrated that it is possible to obtain transformed plants with a single and intact 50Kb insert, and then we have demonstrated that this insert can be transmitted intact to the T1 progeny.In our knowledge, this is the first time wheat transformation with such a fragment was demonstrated.Developing such technologies could be very useful to improve genetic engineering of wheat which is one of the major food crops in the world

Introduction of a 50 Kb intact DNA fragment into wheat genome by biolistic technology

International audienceGenetic transformation is a powerful tool for studying gene function and regulation of physiological and developmental processes in plants. Although wheat was the last of the major cereal to be transformed, the introduction and expression of transgene in this plant is now quite feasible.Nowadays another challenge in plant transformation technology is the introduction and stable integration of large intact DNA fragments in plant genome. It would make possible the study in one transformation step of multigenic traits or to study the expression of plant gene in their native genomic context. Recently, it has been shown that expression and regulation of a gene frequently require regulatory elements that could be very distantIn the present study we developed a technology, based on biolistic with dephosphorylated cassettes allowing introduction of a 50 kb intact insert DNA in wheat genome. We have chosen Arabidopsis thaliana DNA as large insert fragments to make easier insert detection, and we have flanked the insert by two reporter genes in order to facilitate screening of plants containing the entire cassette.We have first demonstrated that it is possible to obtain transformed plants with a single and intact 50Kb insert, and then we have demonstrated that this insert can be transmitted intact to the T1 progeny.In our knowledge, this is the first time wheat transformation with such a fragment was demonstrated.Developing such technologies could be very useful to improve genetic engineering of wheat which is one of the major food crops in the world

Identification of glycosyltransferases involved in cell wall synthesis of wheat endosperm.

International audiencePlant cell walls are complex structures critical for plant fitness and valuable for human nutrition as dietary fiber and for industrial uses such as biofuel production. The cell wall polysaccharides in wheat endosperm consist of two major polymers, arabinoxylans and beta-glucans, as well as other minor components. Most of these polysaccharides are synthesized in the Golgi apparatus but the mechanisms underlying their synthesis have yet to be fully elucidated and only a few of the enzymes involved have been characterized. To identify actors involved in the wheat endosperm cell wall formation, we used a subcellular fractionation strategy to isolate Golgi-enriched fractions from endosperm harvested during active cell wall deposition. The proteins extracted from these Golgi-enriched fractions were analyzed by LC-MS/MS. We report the identification of 1135 proteins among which 64 glycosyltransferases distributed in 17 families. Their potential function in cell wall synthesis is discussed. In addition, we identified 63 glycosylhydrolases, some of which may be involved in cell wall remodeling. Several glycosyltransferases were validated by showing that when expressed as fusion proteins with a fluorescent reporter, they indeed accumulate in the Golgi apparatus. Our results provide new candidates potentially involved in cell wall biogenesis in wheat endosperm