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Optimization of HTS hit 1 for NPY Y5 receptor binding affinity, CYP450 inhibition, solubility and metabolic stability led to the identification of some orally available oxygen-linker derivatives for in vivo study. Among them, derivative 4i inhibited food intake induced by the NPY Y5 selective agonist, and chronic oral administration of 4i in DIO mice caused a dose-dependent reduction of body weight gain.  相似文献   
33.
Cryptomeria japonica pollinosis is one of the most serious allergic diseases in Japan; this is a social problem because C. japonica is the most important Japanese forestry species. In order to reduce the amount of pollen dispersed, breeding programs using trees with male-sterile genes have been implemented. High-density linkage maps with stable ordering of markers facilitate the localization of male-sterile genes and the construction of partial linkage maps around them in order to develop markers for use in marker-assisted selection. In this study, a high-density linkage map for C. japonica with 2560 markers was constructed. The observed map length was 1266.2 cM and the mean distance between adjacent markers was 0.49 cM. Using information from this high-density map, we newly located two male-sterile genes (ms3 and ms4) on the first and fourth linkage groups, respectively, and constructed partial linkage maps around these loci. We also constructed new partial linkage maps around the ms1 and ms2 loci using additional SNP markers. The closest markers to the ms1, ms2, ms3, and ms4 male-sterile loci were estSNP04188 (1.8 cM), estSNP00695 (7.0 cM), gSNP05415 (3.1 cM), and estSNP01408 (7.0 cM) respectively. These results allowed us to develop SNP markers tightly linked to the male sterile genes for use in MAS; this will accelerate the future isolation of these genes by map-based cloning approaches.  相似文献   
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Abstract

CD1d is a non-polymorphic antigen-presenting glycoprotein that recognizes glycolipids as ligands. Ligands bind to the hydrophobic grooves of CD1d, and the resulting ligand-CD1d complexes activate natural killer T (NKT) cells by means of T cell receptor recognition, leading to the secretion of various cytokines. However, details of the ligand recognition mechanism of a large hydrophobic ligand binding pocket and the relationship between cytokine induction and ligand structure are unclear. We report the synthesis of α-GalCer derivatives containing a Bz amide group having various substituting groups in the ceramide moiety, and the analysis of the structure-activity relationships. The assays reveal that the Bz amide-containing CD1d ligands function as NKT cell modulators displaying Th2 cytokine biasing responses. Furthermore, molecular dynamics simulation studies suggest that the phenyl groups can interact with the aromatic amino acid residues in the lipid binding pocket of CD1d.  相似文献   
36.
Artificial RING fingers (ARFs) are created by transplanting active sites of RING fingers onto cross‐brace structures. Human hydroxymethylglutaryl‐coenzyme A reductase degradation protein 1 (HRD1) is involved in the degradation of the endoplasmic reticulum (ER) proteins. HRD1 possesses the RING finger domain (HRD1_RING) that functions as a ubiquitin‐ligating (E3) enzyme. Herein, we determined the solution structure of HRD1_RING using nuclear magnetic resonance (NMR). Moreover, using a metallochromic indicator, we determined the stoichiometry of zinc ions spectrophotometrically and found that HRD1_RING binds to two zinc atoms. The Simple Modular Architecture Research Tool database predicted the structure of HRD1_RING as a typical RING finger. However, it was found that the actual structure of HRD1_RING adopts an atypical RING‐H2 type RING fold. This structural analysis unveiled the position and range of the active site of HRD1_RING that contribute to its specific ubiquitin‐conjugating enzyme (E2)‐binding capability.  相似文献   
37.
Lewis acid-promoted reactions of peracetylated sugars (glucose, galactose, maltose, lactose) with omega-bromo-1-alkanols (C(8), C(12)) were investigated. ZnCl(2) was found to promote the 1,2-trans-glycosylation of the alcohols in toluene at about 60 degrees C in a stereocontrolled manner with better yields than commonly employed promoters such as SnCl(4). The omega-bromoalkyl acetylated glycosides were readily converted to omega-mercaptoalkyl glycosides, which are useful for the preparation of glycoclusters.  相似文献   
38.
Nod1 is an intracellular protein that is involved in recognition of bacterial molecules and whose genetic variation has been linked to several inflammatory diseases. Previous studies suggested that the recognition core of Nod1 stimulatory molecules is gamma-D-glutamyl-meso-diaminopimelic acid (iE-DAP), but the identity of the major Nod1 stimulatory molecule produced by bacteria remains unknown. Here we show that bacteria produce lipophilic molecules capable of stimulating Nod1. Analysis of synthetic compounds revealed stereoselectivity of the DAP residue and that conjugation of lipophilic acyl residues specifically enhances the Nod1 stimulatory activity of the core iE-DAP. Furthermore, we demonstrate that lipophilic molecules induce and/or enhance the secretion of innate immune mediators from primary mouse mesothelial cells and human monocytic MonoMac6 cells, and this effect is mediated through Nod1. These results provide insight into the mechanism of immune recognition via Nod1, which might be useful in the design and testing of novel immunoregulators.  相似文献   
39.
Nucleocytoplasmic translocation constitutes a foundation for nuclear proteins to exert their proper functions and hence for various biological reactions to occur normally in eukaryotic cells. We reported previously that EZI/Zfp467, a 12 zinc finger motif-containing protein, localizes predominantly in the nucleus, yet the underlying mechanism still remains elusive. Here we constructed a series of mutant forms of EZI and examined their subcellular localization. The results delineated a non-canonical nuclear localization signal in the region covering the 9th to the 12th zinc fingers, which was necessary for nuclear accumulation of EZI as well as sufficient to confer nuclear localizing ability to a heterologous protein. We also found that the N-terminal domain of EZI is necessary for its nuclear export, the process of which was not sensitive to the CRM1 inhibitor leptomycin B. An interaction proteomics approach and the following co-immunoprecipitation experiments identified the nuclear import receptor importin-7 as a molecule that associated with EZI and, importantly, short interfering RNA-mediated knockdown of importin-7 expression completely abrogated nuclear accumulation of EZI. Taken together, these results identify EZI as a novel cargo protein for importin-7 and demonstrate a nucleocytoplasmic shuttling mechanism that is mediated by importin-7-dependent nuclear localization and CRM1-independent nuclear export.  相似文献   
40.
High accumulation and selective delivery of boron into tumor tissues are the most important requirements to achieve efficient neutron capture therapy of cancers. We focused on liposomal boron delivery system to achieve a large amount of boron delivery to tumor. We succeeded in the synthesis of the double-tailed boron cluster lipids 4a–c and 5a–c, which has a B12H11S-moiety as a hydrophilic function, by S-alkylation of B12H11SH with bromoacetyl and chloroacetocarbamate derivatives of diacylglycerols. Size distribution of liposomes prepared from the boron cluster lipid 4b, dimyristoylphosphatidylcholine, polyethyleneglycol-conjugated distearoylphosphatidylethanolamine, and cholesterol was determined as 100 nm in diameter by an electrophoretic light scattering spectrophotometer. Calcein-encapsulation experiments revealed that these boronated liposomes are stable at 37 °C in fetal bovine serum solution for 24 h.  相似文献   
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