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991.
Ronan Sulpice Anna Flis Alexander A. Ivakov Federico Apelt Nicole Krohn Beatrice Encke Christin Abel Regina Feil John E. Lunn Mark Stitt 《植物生理与分子生物学学报》2014,(1):137-155
In short photoperiods, plants accumulate starch more rapidly in the light and degrade it more slowly at night, ensuring that their starch reserves last until dawn. To investigate the accompanying changes in the timing of growth, Arabidopsis was grown in a range of photoperiods and analyzed for rosette biomass, photosynthesis, respiration, ribosome abundance, polysome loading, starch, and over 40 metabolites at dawn and dusk. The data set was used to model growth rates in the daytime and night, and to identify metabolites that correlate with growth. Modeled growth rates and polysome loading were high in the daytime and at night in long photoperiods, but decreased at night in short photoperiods. Ribosome abundance was similar in all photoperiods. It is discussed how the amount of starch accumulated in the light period, the length of the night, and maintenance costs interact to constrain growth at night in short photoperiods, and alter the strategy for optimizing ribosome use. Significant correlations were found in the day- time and the night between growth rates and the levels of the sugar-signal trehalose 6-phosphate and the amino acid biosynthesis intermediate shikimate, identifying these metabolites as hubs in a network that coordinates growth with diurnal changes in the carbon supply. 相似文献
992.
CRISPR-P: A Web Tool for Synthetic Single-Guide RNA Design of CRISPR-System in Plants 总被引:1,自引:0,他引:1
《植物生理与分子生物学学报》2014,(9):1494-1496
993.
根据已知耐热甘露聚糖酶ManAd3氨基酸序列与毕赤酵母密码子使用偏爱性,设计并合成了甘露聚糖酶ManA全基因(Accession No.KJ806637),与表达载体pPIC9k重组后,转化毕赤酵母GS115,筛选获得重组菌株ManA-GS115。该重组菌株发酵产物经SDS-PAGE鉴定,其中甘露聚糖酶ManA含量达到电泳纯级别,分子量大小约为30 kDa。其酶学性质检测结果显示该酶最适反应温度为75℃,最适反应pH为6.0,比活力高达3200 IU/mg,并且在75℃下处理30 min仍能维持90%以上相对酶活力。该甘露聚糖酶ManA表达量较高,在偏酸性环境下仍能够维持较高的相对酶活力,且热稳定性显著,可广泛应用于食品、酿造、饲料、纺织和医药等工业领域。 相似文献
994.
Agnieszka Ludwikow ;Agata Ciesla ;Anna Kasprowicz-Malusk ;Filip Mitula ;Malgorzata Tajdel ;lukasz Gaigarnski ;Piotr A. Ziolkowski ;Piotr Kubiak ;Arleta Malecka ;Aneta Piechalak ;Marta Szabat ;Alicja Gorska ;Maciej Dabrowskia ;Izabela Ibragimow ;Jan Sadowski 《植物生理与分子生物学学报》2014,(6):960-976
Ethylene plays a crucial role in various biological processes and therefore its biosynthesis is strictly regu- lated by multiple mechanisms. Posttranslational regulation, which is pivotal in controlling ethylene biosynthesis, impacts 1-aminocyclopropane 1-carboxylate synthase (ACS) protein stability via the complex interplay of specific factors. Here, we show that the Arabidopsis thaliana protein phosphatase type 2C, ABI1, a negative regulator of abscisic acid signaling, is involved in the regulation of ethylene biosynthesis under oxidative stress conditions. We found that ABI1 interacts with ACS6 and dephosphorylates its C-terminal fragment, a target of the stress-responsive mitogen-activated protein kinase, MPK6. In addition, ABI1 controls MPK6 activity directly and by this means also affects the ACS6 phosphorylation level. Consistently with this, ozone-induced ethylene production was significantly higher in an ABI1 knockout strain (abiltd) than in wild-type plants. Importantly, an increase in stress-induced ethylene production in the abiltd mutant was compen- sated by a higher ascorbate redox state and elevated antioxidant activities. Overall, the results of this study provide evi- dence that ABI1 restricts ethylene synthesis by affecting the activity of ACS6. The ABI1 contribution to stress phenotype underpins its role in the interplay between the abscisic acid (ABA) and ethylene signaling pathways. 相似文献
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996.
《现代生物医学进展》2014,(25):2
英国《自然》杂志近日公布的一项合成生物学研究显示,科学家首次将人工合成碱基对插入大肠杆菌的DNA(脱氧核糖核酸)中,且并未影响其生长和复制过程。这一成果向利用合成技术"订制"特定生物组织迈进一步。遗传物质DNA由两条很长的糖链结构形成骨架,通过碱基对的结合形成稳定的螺旋结构。自然界的生命多姿多彩,最基本的碱基对却只有两种:腺嘌呤-胸腺嘧啶(A-T)和胞嘧啶-鸟嘌呤(C-G)。但美国研究人员构建出一种自然界不存在的生物体,它稳定包含一种代号为"X-Y"的 相似文献
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998.
Lipidomics is increasingly becoming a viable method for researchers to routinely identify the various sterols present in samples, beyond just measuring cholesterol itself. In particular, the measurement of intermediates in cholesterol synthesis can shed new insights into not only the flux through the pathway, but also numerous disease states where levels of sterol intermediates are drastically altered. In this review, we indicate several intermediates that are relevant to disease, and discuss the challenges for analysing them, including the need for standardised methodology or universal controls across the lipidomics field. 相似文献
999.
对2-甲基-4-硝基-吡啶-N-氧化物的合成方法进行了工艺改进,以2-甲基吡啶为原料,经氧化、硝化合成目标产物。总产率达到70.36%。 相似文献
1000.