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191.
Auxin-signaling: short and long   总被引:1,自引:0,他引:1  
  相似文献   
192.
On the basis of potent and selective binding affinity of Cl-IB-MECA to the human A(3) adenosine receptor, its 4'-thioadenosine derivatives were efficiently synthesized starting from D-gulonic gamma-lactone. Among compounds tested, 2-chloro-N(6)-(3-iodobenzyl)- and 2-chloro-N(6)-methyl-4' -thioadenosine-5' -methyluronamides (7a and 7b) exhibited nanomolar range of binding affinity (K(i) = 0.38 nM and 0.28 nM, respectively) at the human A(3)AR. These compounds showed anti-growth effects on HL-60 leukemia cell, which resulted from the inhibition of Wnt signaling pathway.  相似文献   
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A search for a suitable replacement for the central norbornyl scaffold presented in the recently disclosed novel FLAP inhibitors is herein described, as well as the SAR study performed on the endo and exo-aryl groups.  相似文献   
197.
Wu  Liang  Ok  Yong Sik  Xu  Xing Liang  Kuzyakov  Yakov 《Plant and Soil》2012,354(1-2):311-324
Plant and Soil - Various anionic polyacrylamide polymers (PAMs) are frequently used to improve soil properties and reduce erosion. However, the effects of their application on plant growth remain...  相似文献   
198.
The immunophilin-like protein TWISTED DWARF1 (TWD1/FKBP42) has been shown to physically interact with the multidrug resistance/P-glycoprotein (PGP) ATP-binding cassette transporters PGP1 and PGP19 (MDR1). Overlapping phenotypes of pgp1/pgp19 and twd1 mutant plants suggested a positive regulatory role of TWD1 in PGP-mediated export of the plant hormone auxin, which controls plant development. Here, we provide evidence at the cellular and plant levels that TWD1 controls PGP-mediated auxin transport. twd1 and pgp1/pgp19 cells showed greatly reduced export of the native auxin indole-3-acetic acid (IAA). Constitutive overexpression of PGP1 and PGP19, but not TWD1, enhanced auxin export. Coexpression of TWD1 and PGP1 in yeast and mammalian cells verified the specificity of the regulatory effect. Employing an IAA-specific microelectrode demonstrated that IAA influx in the root elongation zone was perturbed and apically shifted in pgp1/pgp19 and twd1 roots. Mature roots of pgp1/pgp19 and twd1 plants revealed elevated levels of free IAA, which seemed to account for agravitropic root behavior. Our data suggest a novel mode of PGP regulation via FK506-binding protein-like immunophilins, implicating possible alternative strategies to overcome multidrug resistance.  相似文献   
199.
Bacillus strain JF-2 (ATCC 39307) is a halotolerant, biosurfactant-producing bacterium that was initially described as a member of the species Bacillus licheniformis based on a limited set of phenotypic characteristics. Here, genetic and phenotypic analyses were employed to determine the relationship of Bacillus strain JF-2 to other Bacillus strains. The restriction patterns with AluI and analysis of gyrA and 16S rRNA gene sequences grouped Bacillus strain JF-2 with B. mojavensisT and not with B. licheniformisT. DNA–DNA similarity showed JF-2 was 75% similar to B. mojavensisT and only 11% similar to B. licheniformisT. Both strain JF-2 and B. mojavensisT required DNA for anaerobic growth, but B. licheniformisT did not. B. mojavensisT and strain JF-2 did not grow anaerobically in thioglycollate medium or aerobically with propionate while B. licheniformisT grew under these conditions. DNA–DNA similarity, gene sequence data and phenotypic characteristics all support the assignment of JF-2 as a member of the species B. mojavensis.  相似文献   
200.
A murine model immunized with plasmid DNA vaccine expressing three glycoproteins pCIgB, pCIgC and pCIgD were used to examine the relative potency of major glycoproteins as well as the contribution of immunological parameters in providing protective immunity against the pseudorabies virus (PrV). Among the three glycoprotein-encoded plasmid DNA vaccines, pCIgB produced the strongest response of PrV-specific IgG in the sera. pCIgB and pCIgD also induced a contrast pattern of immunity that was biased to the Th1 and Th2 types, respectively. pCIgC showed the potent inducer of CD8+ T-cell-mediated CTL activity against PrV. In addition, a cocktail vaccination of all three glycoprotein-encoded plasmid DNA vaccines induced the production of both cytokine types, Th1 and Th2 with levels that were the same as that of each immunogen. With regard to protective efficacy, pCIgB induced the most effective protection against a virulent virus challenge and a cocktail vaccination appeared to offer complete protection against a 5 LD50 challenge, but not a 10 LD50 one. pCIgD induced protection that was same as pCIgB, but pCIgC offered no effective protection. These results show the relative potency of the three glycoprotein-encoded PrV DNA vaccines in inducing protective immunity against PrV infection. The results in this study support previous results showing the importance of Th1-type CD4+ T cells and their antibodies in conferring protection.  相似文献   
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