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131.
Yan Li Wahyu Surya Stephanie Claudine Jaume Torres 《The Journal of biological chemistry》2014,289(18):12535-12549
Coronavirus envelope (CoV E) proteins are ∼100-residue polypeptides with at least one channel-forming α-helical transmembrane (TM) domain. The extramembrane C-terminal tail contains a completely conserved proline, at the center of a predicted β-coil-β motif. This hydrophobic motif has been reported to constitute a Golgi-targeting signal or a second TM domain. However, no structural data for this or other extramembrane domains in CoV E proteins is available. Herein, we show that the E protein in the severe acute respiratory syndrome virus has only one TM domain in micelles, whereas the predicted β-coil-β motif forms a short membrane-bound α-helix connected by a disordered loop to the TM domain. However, complementary results suggest that this motif is potentially poised for conformational change or in dynamic exchange with other conformations. 相似文献
132.
Novel quantitative trait loci for broad-based resistance to soybean cyst nematode (Heterodera glycines Ichinohe) in soybean PI 567516C 总被引:1,自引:0,他引:1
Tri D. Vuong David A. Sleper James G. Shannon Henry T. Nguyen 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,121(7):1253-1266
Soybean cyst nematode (SCN, Heterodera glycines Ichinohe) is the most destructive pest of soybean worldwide. Host plant resistance is an effective approach to control this
pest. Plant introduction PI 567516C has been reported to be highly resistant to multiple-HG types of SCN. The objectives of
this study were to identify and map novel quantitative trait loci (QTL) for SCN resistance to six HG types (also known as
races 1, 2, 3, 5, 14, and LY1). Mapping was conducted using 250 F2:3 progeny derived from a Magellan (susceptible) × PI 567516C (resistant) cross. F6:7 recombinant inbred lines (RILs) developed from the F2:3 progeny were employed to confirm the putative QTL identified. A total of 927 polymorphic simple sequence repeats (SSR) and
single nucleotide polymorphism (SNP) markers were genotyped. Following the genetic linkage analysis, permutation tests and
composite interval mapping were performed to identify and map QTL. Four QTL were associated with resistance to either multiple-
or single-SCN HG types. Two QTL for resistance to multiple-SCN HG types were mapped to Chromosomes 10 and 18 and have not
been reported in other SCN resistance sources. New QTL were confirmed by analysis of 250 F6:7 RILs from the same population. SSR and SNP markers closely associated with these QTL can be useful for the development of
near-isogenic lines for fine-mapping and positional cloning of candidate genes for SCN resistance. 相似文献
133.
Huong Thuy Le Thien-Y Vu Tran-Van-Anh Nguyen Mai Dinh Tri Nguyen-Kim-Tuyen Pham Huy Truong Nguyen Ngoc-Hong Nguyen Huu-Hung Nguyen Thuc-Huy Duong 《化学与生物多样性》2023,20(6):e202300319
Sphaeranthus africanus L. is native in Vietnam. Little is known about α-glucosidase inhibition of Sphaeranthus africanus and its isolated compounds. A bioactive-guided isolation was applied to the Vietnamese Sphaeranthus africanus to find α-glucosidase inhibitory components. Eight compounds were detected and structurally elucidated. They are 3-angeloyloxy-5-[2′′,3′′-epoxy-2′′-methylbutanoyloxy]-7-hydroxycarvotacetone, 3-angeloyloxy-5-[3′′-chloro-2′′-hydroxy-2′′-methylbutanoyloxy]-7-hydroxycarvotacetone, 3-angeloyloxy-5-[2′′R,3′′R-dihydroxy-2′′-methyl-butanoyloxy]-7-hydroxycarvotacetone, 3-angeloyloxy-5-[2′′S,3′′R-dihydroxy-2′′-methylbutanoyloxy]-7-hydroxycarvotacetone, 3-angeloyloxy-5-[2′′S,3′′S-dihydroxy-2′′-methylbutanoyloxy]-7-hydroxycarvotacetone, 5-angeloyloxy-7-hydroxy-3-tigloyloxycarvotacetone, 3-O-methylquercetin, and chrysosplenol D. Their chemical structures were elucidated by extensive 1D and 2D NMR analysis and high-resolution mass spectroscopy as well as comparisons in literature. 3-Angeloyloxy-5-[2′′S,3′′S-dihydroxy-2′′-methylbutanoyloxy]-7-hydroxycarvotacetone is a new compound. Isolated compounds were evaluated for the α-glucosidase inhibition. Isolated compounds showed moderate activity with IC50 values ranging from 128.9–274.3 μM while others are weak. A molecular docking study was conducted, indicating that isolated compounds are potent α-glucosidase inhibitory compounds. 相似文献
134.
135.
Although the asymmetry in the upward and downward bending of insect wings is well known, the structural origin of this asymmetry is not yet clearly understood. Some researchers have suggested that based on experimental results, the bending asymmetry of insect wings appears to be a consequence of the camber inherent in the wings. Although an experimental approach can reveal this phenomenon, another method is required to reveal the underlying theory behind the experimental results. The finite element method (FEM) is a powerful tool for evaluating experimental measurements and is useful for studying the bending asymmetry of insect wings. Therefore, in this study, the asymmetric bending of the Allomyrina dichotoma beetle''s hind wing was investigated through FEM analyses rather than through an experimental approach. The results demonstrated that both the stressed stiffening of the membrane and the camber of the wing affect the bending asymmetry of insect wings. In particular, the chordwise camber increased the rigidity of the wing when a load was applied to the ventral side, while the spanwise camber increased the rigidity of the wing when a load was applied to the dorsal side. These results provide an appropriate explanation of the mechanical behavior of cambered insect wings, including the bending asymmetry behavior, and suggest an appropriate approach for analyzing the structural behavior of insect wings. 相似文献
136.
137.
Ho QT Verboven P Verlinden BE Herremans E Wevers M Carmeliet J Nicolaï BM 《Plant physiology》2011,155(3):1158-1168
Respiration of bulky plant organs such as roots, tubers, stems, seeds, and fruit depends very much on oxygen (O2) availability and often follows a Michaelis-Menten-like response. A multiscale model is presented to calculate gas exchange in plants using the microscale geometry of the tissue, or vice versa, local concentrations in the cells from macroscopic gas concentration profiles. This approach provides a computationally feasible and accurate analysis of cell metabolism in any plant organ during hypoxia and anoxia. The predicted O2 and carbon dioxide (CO2) partial pressure profiles compared very well with experimental data, thereby validating the multiscale model. The important microscale geometrical features are the shape, size, and three-dimensional connectivity of cells and air spaces. It was demonstrated that the gas-exchange properties of the cell wall and cell membrane have little effect on the cellular gas exchange of apple (Malus×domestica) parenchyma tissue. The analysis clearly confirmed that cells are an additional route for CO2 transport, while for O2 the intercellular spaces are the main diffusion route. The simulation results also showed that the local gas concentration gradients were steeper in the cells than in the surrounding air spaces. Therefore, to analyze the cellular metabolism under hypoxic and anoxic conditions, the microscale model is required to calculate the correct intracellular concentrations. Understanding the O2 response of plants and plant organs thus not only requires knowledge of external conditions, dimensions, gas-exchange properties of the tissues, and cellular respiration kinetics but also of microstructure. 相似文献
138.
Wu X Vuong TD Leroy JA Grover Shannon J Sleper DA Nguyen HT 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,122(6):1179-1187
Soybean BAC-based physical maps provide a useful platform for gene and QTL map-based cloning, EST mapping, marker development,
genome sequencing, and comparative genomic research. Soybean physical maps for “Forrest” and “Williams 82” representing the
southern and northern US soybean germplasm base, respectively, have been constructed with different fingerprinting methods.
These physical maps are complementary for coverage of gaps on the 20 soybean linkage groups. More than 5,000 genetic markers
have been anchored onto the Williams 82 physical map, but only a limited number of markers have been anchored to the Forrest
physical map. A mapping population of Forrest × Williams 82 made up of 1,025 F8 recombinant inbred lines (RILs) was used to construct a reference genetic map. A framework map with almost 1,000 genetic
markers was constructed using a core set of these RILs. The core set of the population was evaluated with the theoretical
population using equality, symmetry and representativeness tests. A high-resolution genetic map will allow integration and
utilization of the physical maps to target QTL regions of interest, and to place a larger number of markers into a map in
a more efficient way using a core set of RILs. 相似文献
139.
Firyal Dhiyaul Haqqi Arief Sudarmaji Wahyu Edy Wibowo Nuruddin Nasution Handoko Handoko Annisa Rahma Fauzia Jihadil Qudsi Supriyanto Ardjo Pawiro 《Reports of Practical Oncology and Radiotherapy》2022,27(2):360
BackgroundThis study aimed to evaluate the target volume and dose accuracy in intrafraction cases using 4-dimensional imaging modalities and an in-house dynamic thorax phantom. Intrafraction motion can create errors in the definition of target volumes, which can significantly affect the accuracy of radiation delivery. Motion management using 4-dimensional modalities is required to reduce the risk.Materials and methodsTwo variations in both breathing amplitude and target size were applied in this study. From these variations, internal target volume (ITVs) contoured in 10 phases of 4D-CT (ITV10), average intensity projection (AIP), and mid-ventilation (Mid-V) images were reconstructed from all 4D-CT datasets as reference images. Free-breathing (FB), augmentation free-breathing (Aug-FB), and static images were also acquired using the 3D-CT protocol for comparisons. In dose evaluations, the 4D-CBCT modality was applied before irradiation to obtain position correction. Then, the dose was evaluated with Gafchromic film EBT3.ResultsThe ITV10, AIP, and Mid-V provide GTVs that match the static GTV. The AIP and Mid-V reference images allowed reductions in ITVs and PTVs without reducing the range of target movement areas compared to FB and Aug-FB images with varying percentages in the range of 29.17% to 48.70%. In the dose evaluation, the largest discrepancies between the measured and planned doses were 10.39% for the FB images and 9.21% for the Aug-FB images.ConclusionThe 4D-CT modality can enable accurate definition of the target volume and reduce the PTV. Furthermore, 4D-CBCT provides localization images during registration to facilitate position correction and accurate dose delivery. 相似文献
140.
Eastburn A Scherzer R Zolopa AR Benson C Tracy R Do T Bacchetti P Shlipak M Grunfeld C Tien PC 《PloS one》2011,6(11):e26320