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991.
During prepupal stage, the genes expression in silkgland is considered as a model for gene expression and regulation of eukaryotes. Aiming to comprehensively interpret gene expression profile in the silkgland, we collected all currently available EST, complete cDNA and protein expression information and other gene expression testing data published before, and explored their roles in their function pathways level. With the analysis of interaction between the known proteins and putative bio-macromolecules partners in silico, we list our prediction results in the form of pathway classification and test some of their expressions by experiments. 相似文献
992.
家蝇卵黄蛋白基因编码的卵黄蛋白是家蝇胚胎发育的重要营养来源 .根据 3种家蝇卵黄蛋白cDNA保守序列设计引物 ,用PCR技术从家蝇基因组DNA中扩增到大小为 76 8bp的mdYP1基因的部分DNA片段 .经地高辛标记成特异性探针 ,从构建的家蝇基因组文库中筛选出一个阳性克隆 ,并从该克隆中分离到大小为 3991bp的mdYP1基因组基因 .序列分析显示 ,该基因组序列含有约1 6kb的 5′ 上游区和 1 0kb的 3′ 下游区 ,编码区由一个 6 1bp的内含子和大小分别为 2 2 2bp和10 2 8bp的 2个外显子组成 .5′ 上游区含有典型的CAAT TATA盒 . 相似文献
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Hieu T. H. Nguyen François Bouteau Christian Mazars Masaki Kuse 《Bioscience, biotechnology, and biochemistry》2019,83(2):318-321
Dimethyl sulfoxide (DMSO) is a dipolar aprotic solvent widely used in biological assays. Here, we observed that DMSO enhanced the hypo-osmotically induced increases in the concentration of Ca2+ in cytosolic and nucleic compartments in the transgenic cell-lines of tobacco (BY-2) expressing aequorin. 相似文献
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997.
Flores SC Keating KS Painter J Morcos F Nguyen K Merritt EA Kuhn LA Gerstein MB 《Proteins》2008,73(2):299-319
Protein motion is often the link between structure and function and a substantial fraction of proteins move through a domain hinge bending mechanism. Predicting the location of the hinge from a single structure is thus a logical first step towards predicting motion. Here, we describe ways to predict the hinge location by grouping residues with correlated normal-mode motions. We benchmarked our normal-mode based predictor against a gold standard set of carefully annotated hinge locations taken from the Database of Macromolecular Motions. We then compared it with three existing structure-based hinge predictors (TLSMD, StoneHinge, and FlexOracle), plus HingeSeq, a sequence-based hinge predictor. Each of these methods predicts hinges using very different sources of information-normal modes, experimental thermal factors, bond constraint networks, energetics, and sequence, respectively. Thus it is logical that using these algorithms together would improve predictions. We integrated all the methods into a combined predictor using a weighted voting scheme. Finally, we encapsulated all our results in a web tool which can be used to run all the predictors on submitted proteins and visualize the results. 相似文献
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999.
This study examined the 20-yr trend of natural restoration of a degraded rangeland ecosystem after disturbance in Heshan hilly land. The results showed that herbs and shrubs were the dominant plants in the community and only a small number of the shade-intolerant tree species had invaded, showing the characteristics of assembly of pioneer communities. The organic matter content, soluble nitrogen, available phosphorus and available potassium had recovered to the level of the local climax community. Part of the ecological functions such as water and soil conservation had also recovered. While the functions of water and soil conservation recovered first, more time was needed for productivity and other functions to completely recover, suggesting the idiosyncratic nature of different ecosystem variables in response to time and microclimate change. Particularly, nutrient cycling recovered very slowly by natural restoration and artificial plantation may be necessary to accelerate the restoration process. 相似文献
1000.
Lubomir Prochazka Stepan Koudelka Lan-Feng Dong Jan Stursa Jacob Goodwin Jiri Neca Josef Slavik Miroslav Ciganek Josef Masek Katarina Kluckova Maria Nguyen Jaroslav Turanek Jiri Neuzil 《Apoptosis : an international journal on programmed cell death》2013,18(3):286-299
α-Tocopheryl succinate (α-TOS) is a promising anti-cancer agent due to its selectivity for cancer cells. It is important to understand whether long-term exposure of tumour cells to the agent will render them resistant to the treatment. Exposure of the non-small cell lung carcinoma H1299 cells to escalating doses of α-TOS made them resistant to the agent due to the upregulation of the ABCA1 protein, which caused its efflux. Full susceptibility of the cells to α-TOS was restored by knocking down the ABCA1 protein. Similar resistance including ABCA1 gene upregulation was observed in the A549 lung cancer cells exposed to α-TOS. The resistance of the cells to α-TOS was overcome by its mitochondrially targeted analogue, MitoVES, that is taken up on the basis of the membrane potential, bypassing the enhanced expression of the ABCA1 protein. The in vitro results were replicated in mouse models of tumours derived from parental and resistant H1299 cells. We conclude that long-term exposure of cancer cells to α-TOS causes their resistance to the drug, which can be overcome by its mitochondrially targeted counterpart. This finding should be taken into consideration when planning clinical trials with vitamin E analogues. 相似文献