34 research outputs found

    Untranslated regions of diverse plant viral RNAs vary greatly in translation enhancement efficiency

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    Background: Whole plants or plant cell cultures can serve as low cost bioreactors to produce massive amounts of a specific protein for pharmacological or industrial use. To maximize protein expression, translation of mRNA must be optimized. Many plant viral RNAs harbor extremely efficient translation enhancers. However, few of these different translation elements have been compared side-by-side. Thus, it is unclear which are the most efficient translation enhancers. Here, we compare the effects of untranslated regions (UTRs) containing translation elements from six plant viruses on translation in wheat germ extract and in monocotyledenous and dicotyledenous plant cells.Results: The highest expressing uncapped mRNAs contained viral UTRs harboring Barley yellow dwarf virus (BYDV)-like cap-independent translation elements (BTEs). The BYDV BTE conferred the most efficient translation of a luciferase reporter in wheat germ extract and oat protoplasts, while uncapped mRNA containing the BTE from Tobacco necrosis virus-D translated most efficiently in tobacco cells. Capped mRNA containing the Tobacco mosaic virus omega sequence was the most efficient mRNA in tobacco cells. UTRs from Satellite tobacco necrosis virus, Tomato bushy stunt virus, and Crucifer-infecting tobamovirus (crTMV) did not stimulate translation efficiently. mRNA with the crTMV 5′ UTR was unstable in tobacco protoplasts.Conclusions: BTEs confer the highest levels of translation of uncapped mRNAs in vitro and in vivo, while the capped omega sequence is most efficient in tobacco cells. These results provide a basis for understanding mechanisms of translation enhancement, and for maximizing protein synthesis in cell-free systems, transgenic plants, or in viral expression vectors

    Comparison of vapour pressure deficit patterns during cucumber cultivation in a traditional high PE tunnel greenhouse and a tunnel greenhouse equipped with a heat accumulator

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    Plant productivity in protected cultivation is highly influenced by air temperature and humidity. The conditions relating to the moisture content of the air in protected plant cultivation are preferably defined by vapour pressure deficit (VPD), which describes the difference between the maximal and actual water vapour pressure (kPa). VPD is widely used as the parameter describing the climate conditions favourable for the development of fungal diseases and for highlighting conditions unfavourable for plant development. In protected cultivation, both the air temperature and the humidity are influenced by heating systems, and one such system is a heat accumulator, which may store the excessive heat produced during the day by converting the solar energy inside the plastic tunnel, and using it when plant heating is required. The tunnel equipped with a heat accumulator maintained an optimal level of humidity for a longer period, and significantly reduced the time of excessive air humidity. The longest time with an optimal VPD was recorded in August in a tunnel with an accumulator – 30.5% of total time vs. 22.3% of time for control tunnel. The highest difference of total time where the VPD was too low (below 0.2 kPa) was recorded in July – 12.4% of time in a tunnel with an accumulator vs. 39.1% of time for control tunnel. The highest difference of total time with an excessive VPD (over 1.4 kPa) was recorded in May – 12.1% of time in a tunnel with an accumulator vs. 17.9% of time for control tunnel. However, a situation beneficial for plant growth occurred every month during the investigated season

    Morphological and Physiological Responses of Strawberry Plants to Water Stress

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    The most of previous studies have been focused on the effect of water stress on plant yielding. However, the conditions in which plants grow from the moment of planting might affect their morphology and physiological response. The aim of this study was to examine the effect of water deficiency on growth and plant physiological response of strawberry (Fragaria x ananassa Duch. cv. ‘Salut’) under greenhouse conditions. The plants were grown in plastic containers filled with peat substratum. Water stress was imposed by reducing the irrigation according to substratum moisture readings. Water stressed plants had the lowest values of water potential and showed strong decrease in gas exchange rate. Also, biomass and leaf area were the lowest in this group of plants. No differences in the length of root system were observed between control and water stressed plants. The lack of water in growing medium resulted also in a decrease of density and reduction of dimensions of stomata on plant leaves. These changes contribute to optimizing the use of assimilates and water use efficiency in periods when water availability is decreased

    Administracja, zarządzanie i handel zagraniczny w warunkach integracji. Materiały konferencyjne - Handel Zagraniczny

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    Ze wstępu: "Obrady w sekcji H - „Handel zagraniczny” - prowadzone w ramach Międzynarodowej Konferencji Naukowej „Administracja, zarządzanie i handel zagraniczny w warunkach integracj i” dotyczyły szeroko rozumianej wymiany handlowej i współpracy gospodarczej Polski z innymi krajami, zarówno z punktu widzenia gospodarki, jak i poszczególnych przedsiębiorstw. Prezentowane w naszej sekcji referaty dotyczyły w głównej mierze problematyki ujednolicania polskich przepisów w zakresie prowadzenia działalności w szeroko pojętym handlu zagranicznym w celu dostosowania ich do regulacji obowiązujących w Unii Europejskiej."(...

    Zarządzanie i handel zagraniczny w małych i średnich przedsiębiorstwach w warunkach integracji europejskiej: materiały z konferencji

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    Z przedmowy: "Integracja europejska to proces łączenia, scalania się odrębnych ekonomicznie, społecznie, kulturowo gospodarek europejskich krajów. Proces integracji prowadzi do istotnych przekształceń w sferze gospodarki, strategiach organizacji i funkcjonowania przedsiębiorstw, handlu międzynarodowym, działalności marketingowej, strukturach organizacyjnych i mechanizmach ekonomicznych przedsiębiorstw i instytucji działających w krajach integrujących się. Proces integracji to w praktyce proces dostosowywania się struktur gospodarczych; tworzenia związków kooperacyjno-produkcyjnych; powstawania trwałych więzi ekonomicznych między przedsiębiorstwami integrujących się krajów a więc proces kształtowania jednolitego obszaru gospodarczego z odrębnych a często także wzajemnie konkurencyjnych krajów, gospodarek, regionów, gałęzi, branż. Proces międzynarodowej integracji gospodarczej to w dużej mierze proces tworzenia komplementamości przedsiębiorstw i instytucji, komplementamości międzygałęziowej i wewnątrz gałęziowej, w produkcji i wymianie jak też kształtowanie niezbędnej infrastruktury technicznej i ekonomicznej umożliwiającej tworzenie sytemu trwałych powiązań gospodarczych między poszczególnymi krajami."(...

    Morphological and Physiological Responses of Strawberry Plants to Water Stress

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    The most of previous studies have been focused on the effect of water stress on plant yielding. However, the conditions in which plants grow from the moment of planting might affect their morphology and physiological response. The aim of this study was to examine the effect of water deficiency on growth and plant physiological response of strawberry (Fragaria x ananassa Duch. cv. ‘Salut’) under greenhouse conditions. The plants were grown in plastic containers filled with peat substratum. Water stress was imposed by reducing the irrigation according to substratum moisture readings. Water stressed plants had the lowest values of water potential and showed strong decrease in gas exchange rate. Also, biomass and leaf area were the lowest in this group of plants. No differences in the length of root system were observed between control and water stressed plants. The lack of water in growing medium resulted also in a decrease of density and reduction of dimensions of stomata on plant leaves. These changes contribute to optimizing the use of assimilates and water use efficiency in periods when water availability is decreased

    Review article Prevalence and clinical specificity of fatigue symptoms in chronic fatigue syndrome, multiple sclerosis, and myasthenia gravis

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    This article provides a critical review of the psychological and related literature on fatigue resulting in both mental and physical experiences. On one hand, prolonged severe fatigue is a prominent disabling symptom in various diseases of different aetiology – psychiatric (e.g. depression), somatic (e.g. some infections) and neurologic (e.g. multiple sclerosis, myasthenia gravis). For instance, fatigue is a main symptom of myasthenia that leads to pathological skeletal muscle weakness. Furthermore, 40 to 90 per cent of individuals suffering from multiple sclerosis confirm they have experienced fatigue, which impairs their cognitive functioning. In both multiple sclerosis and myasthenia, fatigue has not only a physical but also a psychological dimension. On the other hand, fatigue can be seen as an isolated set of symptoms of unknown origin called the chronic fatigue syndrome (CFS). The development of the concept, diagnostic criteria and some strategies of coping with CFS are presented. Various somatic disorders, as well as subjective cognitive and emotional complaints, are common and well documented in patients with CFS. The most typical include depression, as well as problems with concentration of attention, decision-making and reasoning in complex situations. However, general intellectual abilities and higher order cognitive skills are intact. Directions for future research are outlined

    Untranslated regions of diverse plant viral RNAs vary greatly in translation enhancement efficiency

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    Abstract Background Whole plants or plant cell cultures can serve as low cost bioreactors to produce massive amounts of a specific protein for pharmacological or industrial use. To maximize protein expression, translation of mRNA must be optimized. Many plant viral RNAs harbor extremely efficient translation enhancers. However, few of these different translation elements have been compared side-by-side. Thus, it is unclear which are the most efficient translation enhancers. Here, we compare the effects of untranslated regions (UTRs) containing translation elements from six plant viruses on translation in wheat germ extract and in monocotyledenous and dicotyledenous plant cells. Results The highest expressing uncapped mRNAs contained viral UTRs harboring Barley yellow dwarf virus (BYDV)-like cap-independent translation elements (BTEs). The BYDV BTE conferred the most efficient translation of a luciferase reporter in wheat germ extract and oat protoplasts, while uncapped mRNA containing the BTE from Tobacco necrosis virus-D translated most efficiently in tobacco cells. Capped mRNA containing the Tobacco mosaic virus omega sequence was the most efficient mRNA in tobacco cells. UTRs from Satellite tobacco necrosis virus, Tomato bushy stunt virus, and Crucifer-infecting tobamovirus (crTMV) did not stimulate translation efficiently. mRNA with the crTMV 5′ UTR was unstable in tobacco protoplasts. Conclusions BTEs confer the highest levels of translation of uncapped mRNAs in vitro and in vivo, while the capped omega sequence is most efficient in tobacco cells. These results provide a basis for understanding mechanisms of translation enhancement, and for maximizing protein synthesis in cell-free systems, transgenic plants, or in viral expression vectors.</p
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