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排序方式: 共有239条查询结果,搜索用时 15 毫秒
31.
Suppression of HIV-1 replication by a combination of endonucleolytic ribozymes (RNase P and tRNnase ZL) 总被引:1,自引:0,他引:1
Ikeda M Habu Y Miyano-Kurosaki N Takaku H 《Nucleosides, nucleotides & nucleic acids》2006,25(4-6):427-437
We examined the combinatorial action of RNase P and tRNase ZL-mediated specific inhibition of HIV-1 in cultured cells. We designed two short extra guide sequences (sEGS) that specifically recognize the tat and vifregions of HIV-1 mRNA and mediate the subsequent cleavage of hybridized mRNA by the RNase P and tRNase ZL components. We constructed an RNase P and tRNase ZL-associated vif and tat sEGS expression vector; which used the RNA-polymerase III dependent U6 promoter, as an expression cassette for EGS. Together, the RNase P and tRNase ZL-associated sEGS molecules allow more efficient suppression of HIV-1 mRNA production when separately applied. The possibilities offered by the vector to encode sEGS will provide a powerful tool for gene therapy. 相似文献
32.
Strickland D Lin Y Wagner E Hope CM Zayner J Antoniou C Sosnick TR Weiss EL Glotzer M 《Nature methods》2012,9(4):379-384
Naturally photoswitchable proteins offer a means of directly manipulating the formation of protein complexes that drive a diversity of cellular processes. We developed tunable light-inducible dimerization tags (TULIPs) based on a synthetic interaction between the LOV2 domain of Avena sativa phototropin 1 (AsLOV2) and an engineered PDZ domain (ePDZ). TULIPs can recruit proteins to diverse structures in living yeast and mammalian cells, either globally or with precise spatial control using a steerable laser. The equilibrium binding and kinetic parameters of the interaction are tunable by mutation, making TULIPs readily adaptable to signaling pathways with varying sensitivities and response times. We demonstrate the utility of TULIPs by conferring light sensitivity to functionally distinct components of the yeast mating pathway and by directing the site of cell polarization. 相似文献
33.
Tadeu AM Ribeiro S Johnston J Goldberg I Gerloff D Earnshaw WC 《The EMBO journal》2008,27(19):2510-2522
The mechanism of mitotic chromosome condensation is poorly understood, but even less is known about the mechanism of formation of the primary constriction, or centromere. A proteomic analysis of mitotic chromosome scaffolds led to the identification of CENP-V, a novel kinetochore protein related to a bacterial enzyme that detoxifies formaldehyde, a by-product of histone demethylation in eukaryotic cells. Overexpression of CENP-V leads to hypercondensation of pericentromeric heterochromatin, a phenotype that is abolished by mutations in the putative catalytic site. CENP-V depletion in HeLa cells leads to abnormal expansion of the primary constriction of mitotic chromosomes, mislocalization and destabilization of the chromosomal passenger complex (CPC) and alterations in the distribution of H3K9me3 in interphase nucleoplasm. CENP-V-depleted cells suffer defects in chromosome alignment in metaphase, lagging chromosomes in anaphase, failure of cytokinesis and rapid cell death. CENP-V provides a novel link between centromeric chromatin, the primary constriction and the CPC. 相似文献
34.
35.
Josiah Brown 《The Western journal of medicine》1960,93(3):132-136
As an index to the rate of fat utilization in human subjects, the recovery of all radioactive carbon dioxide in the expired air was measured for one hour following intravenous injection of palmitate-1-C14. In the normal fasted subject, about 10 per cent of the injected dose was recovered, and the proportion was lowered to about 5 per cent by administration of glucose. With prolonged fasting, the recovery of radioactive carbon dioxide did not change, despite a rising concentration of fatty acids in the serum. This was interpreted as due to the development of a balance between increasing mobilization and oxidation and was thought to indicate increasing fatty acid oxidation.In chronic undernutrition and diabetes mellitus there was increased fatty acid oxidation due presumably to adaptation to a chronic increase in fat utilization for energy.Administration of human growth hormone did not increase fat oxidation but prevented the usual inhibition produced by glucose. This was interpreted to mean that growth hormone increases fat utilization only indirectly by inhibiting the usual preferential utilization of glucose over fat. 相似文献
36.
H.M. Hussein R. Zemek S.O. Habuštová E. Prenerová 《Archives Of Phytopathology And Plant Protection》2013,46(11):1307-1319
Laboratory experiments were conducted to assess the efficiency of the new strain CCM 8367 of Isaria fumosorosea on different stages of the Egyptian cotton leafworm, Spodoptera littoralis (Boisd.), including soil treatments with pre-pupal and pupal stages. Treatments of larval instars showed a high susceptibility with 3rd, 5th and last instars to suspension of this fungus with concentration 5?×?107 spores/ml. Larval mortality was over 90%. There were no significant differences (P?=?0.7929, F?=?0.2346) between instar treatments. The commercial fungus, PreFeRal® strain Apopka 97 of I. fumosorosea, which was used in comparison with this new strain caused mortality rates of between 63.33 and 90%. Statistically, differences between the effects of CCM 8367 strain and Apopka 97 were highly significant on the last instar (P?=?0.0064, F?=?6.479) and extremely significant on the 3rd instar (P?<?0.0001, F?=?13.29). No significant differences were recorded between the two strains on the 5th instar (P?=?0.0597, F?=?3.233). Fungal treatments with the late stage insects (end of the last instar or pupal stage) in soil yielded interesting results: the mortality rate on end of final instar larvae was 16.66% when treated with Apopka 97 and 83.33% when treated with CCM 8367. Soil containing pupae of S. littoralis that were inoculated with CCM8367 resulted in a high number of malformed adults, and the mortality rate was 64.52% (32.27% of malformed adults died and 32.25% of pupae fully infected by fungus). Only 3.23% of samples produced morphologically normal adults in this test. The results conclude that the strain of I. fumosorosea CCM 8367 has strong insecticidal effects on S. littoralis and has the potential to be implemented as a novel biocontrol agent. 相似文献
37.
Winged bean Kunitz chymotrypsin inhibitor (WCI) is encoded by a multigene family and accumulation of its mRNA is restricted in mid-maturation stage seeds and tuberous roots. In this paper, we analyzed the accumulation of mRNA derived from each WCI gene using a novel method: sequence-specific termination analysis. The results demonstrated that the accumulation of each WCI mRNA was differentially regulated in winged bean plants. 相似文献
38.
Josiah Oldfield 《BMJ (Clinical research ed.)》1902,1(2154):931-932
39.
Josiah MC Heyman 《The journal of the Royal Anthropological Institute》2000,6(4):635-652
High-scale morality is the study of moral ideas and sentiments deployed in relations that encompass multiple, geographically or socially distant populaces. The envisioning of distant people, their attributed moral personhood, the evaluation of their perceived behaviour, and the rectification of wrongs through the use of powerful organizations are key topics in high-scale morality. High-scale morality differs from existing anthropological approaches that emphasize local ethnography or contrastive moral ideas; it addresses the moralization of issues like world hunger, the drug trade, or international migration. The officers of the US Immigration and Naturalization Service understand and evaluate legal and illegal immigrants, as well as directly enacting moral rectification for the US polity. As they resolve moral dilemmas on their job, they utilize pervasive models for moral thought and action in capitalist, individualist, stratified, and bureaucratized societies. The article finishes by considering directions in which anthropology can contribute to understanding the moral dimension of global issues. 相似文献
40.