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1.
Assessment of genetic diversity and relationship among a collection of US sweet sorghum germplasm by SSR markers 总被引:1,自引:0,他引:1
M. L. Ali J. F. Rajewski P. S. Baenziger K. S. Gill K. M. Eskridge I. Dweikat 《Molecular breeding : new strategies in plant improvement》2008,21(4):497-509
Sweet sorghum (Sorghum bicolor L.) is a type of cultivated sorghums and has been recognized widely as potential alternative source of bio-fuel because of
its high fermentable sugar content in the stalk. A substantial variation of sugar content and related traits is known to exist
in US sweet sorghum. The objectives of the study were to assess the genetic diversity and relationship among the US sweet
sorghum cultivars and lines using SSR markers and to examine the genetic variability within sweet sorghum accessions for sugar
content. Sixty-eight sweet sorghum and four grain sorghum cultivars and lines were genotyped with 41 SSR markers that generated
132 alleles with an average of 3.22 alleles per locus. Polymorphism information content (PIC) value, a measure of gene diversity,
was 0.40 with a range of 0.03–0.87. The genetic similarity co-efficient was estimated based on the segregation of the 132
SSR alleles. Clustering analysis based on the genetic similarity (GS) grouped the 72 sorghum accessions into 10 distinct clusters.
Grouping based on clustering analysis was in good agreement with available pedigree and genetic background information. The
study has revealed the genetic relationship of cultivars with unknown parentage to those with known parentage. A number of
diverse pairs of sweet sorghum accessions were identified which were polymorphic at many SSR loci and significantly different
for sugar content as well. Information generated from this study can be used to select parents for hybrid development to maximize
the sugar content and total biomass, and development of segregating populations to map genes controlling sugar content in
sweet sorghum. 相似文献
2.
《Bioorganic & medicinal chemistry》2016,24(1):1-11
Four kinds of tetravalent double-headed glycoclusters [(LacNAc)4-DHGs] were designed with linkers of varying lengths consisting of alkanedioic carboxyamido groups (C6, C12, C18 and C24) between two bi-antennary LacNAc-glycosides. These glycoclusters served as high-affinity cross-linking ligands for the LacNAc-binding lectin Erythrina cristagalli agglutinin (ECA). The binding activity and cross-linking between each ligand and ECA were characterized by a hemagglutination inhibition (HI) assay, isothermal titration calorimetry (ITC), a quantitative precipitation assay and dynamic light scattering (DLS). For the precipitation assay and DLS measurement, the synthesized (LacNAc)4-DHGs were found to be capable of binding and precipitating the ECA as multivalent ligands. ITC analysis indicated the binding of (LacNAc)4-DHGs was driven by a favorable enthalpy change. Furthermore, the entropy penalty from binding (LacNAc)4-DHGs clearly decreased in a spacer length-dependent manner. The binding affinities of flexible (LacNAc)4-DHGs (C18 and C24) with long spacers were found to be more favorable than those of the clusters having short spacers (C6 and C12). These results were supported by molecular dynamics simulations with explicit water molecules for the tetravalent glycoclusters with ECA. We concluded that the subtle modification in the epitope-presenting scaffolds exerts the significant effect in the recognition efficiency involved in the LacNAc moieties by ECA. 相似文献
3.
Oxygen incorporation in the product of the reaction between YCl3 and the lithium salt of 1,3,4,6,7,8-hexahydro-2Hpyrimido[1,2-a]pyrimidine (hppH) afforded the tetrametallic cluster Y4(hpp)8Cl2(μ4-O), in which four of the guanidinate anions are involved in a previously unreported μ,η2,η2-bridging mode between two metal centres. 相似文献
4.
Genotypic variation in seedling root architectural traits and implications for drought adaptation in wheat (Triticum aestivum L.) 总被引:1,自引:0,他引:1
Ahmad M. Manschadi Graeme L. Hammer John T. Christopher Peter deVoil 《Plant and Soil》2008,303(1-2):115-129
Root system characteristics are of fundamental importance to soil exploration and below-ground resource acquisition. Root
architectural traits determine the in situ space-filling properties of a root system or root architecture. The growth angle
of root axes is a principal component of root system architecture that has been strongly associated with acquisition efficiency
in many crop species. The aims of this study were to examine the extent of genotypic variability for the growth angle and
number of seminal roots in 27 current Australian and 3 CIMMYT wheat (Triticum aestivum L.) genotypes, and to quantify using fractal analysis the root system architecture of a subset of wheat genotypes contrasting
in drought tolerance and seminal root characteristics. The growth angle and number of seminal roots showed significant genotypic
variation among the wheat genotypes with values ranging from 36 to 56 (degrees) and 3 to 5 (plant−1), respectively. Cluster analysis of wheat genotypes based on similarity in their seminal root characteristics resulted in
four groups. The group composition reflected to some extent the genetic background and environmental adaptation of genotypes.
Wheat cultivars grown widely in the Mediterranean environments of southern and western Australia generally had wider growth
angle and lower number of seminal axes. In contrast, cultivars with superior performance on deep clay soils in the northern
cropping region, such as SeriM82, Baxter, Babax, and Dharwar Dry exhibited a narrower angle of seminal axes. The wheat genotypes
also showed significant variation in fractal dimension (D). The D values calculated for the individual segments of each root system suggested that, compared to the standard cultivar Hartog,
the drought-tolerant genotypes adapted to the northern region tended to distribute relatively more roots in the soil volume
directly underneath the plant. These findings suggest that wheat root system architecture is closely linked to the angle of
seminal root axes at the seedling stage. The implications of genotypic variation in the seminal root characteristics and fractal
dimension for specific adaptation to drought environment types are discussed with emphasis on the possible exploitation of
root architectural traits in breeding for improved wheat cultivars for water-limited environments. 相似文献
5.
D. Pangallo K. Chovanov H. Drahovska F. De Leo C. Urzì 《International biodeterioration & biodegradation》2009,63(7):868-872
The aim of this work was the evaluation of fluorescence ITS-PCR (f-ITS) as a molecular tool to analyze the microbial community involved in the biodeterioration of cultural heritage surfaces. As a case study we analyzed by f-ITS ninety-two bacterial strains isolated from a medieval fresco and the surrounding air environment. The internal transcribed spacer between the 16S and 23S rRNA genes was amplified, and then the fluorescently labeled PCR products were separated by capillary electrophoresis. Bacterial strains were identified by 16S rDNA sequencing. The f-ITS electropherograms showed different profiles coherent with the affiliation of the strains at the genus and species levels. Among the isolates obtained from the fresco surface, those belonging to the genus Bacillus were the most prevailing exhibiting 8 different f-ITS profiles. The airborne bacilli exhibited only 2 of these 8 profiles. Staphylococcus were mostly isolated from air and produced 4 different profiles. Pseudomonas isolates presented 3 different profiles, and one of them was typical of Pseudomonas putida. Members of the other genera produced their distinctive profiles. Our results show that f-ITS is a promising molecular tool for the rapid selection and clustering of strains isolated from different sources. 相似文献
6.
Mono- and bis-substituted phosphite complexes [Ru3(CO)12−x Lx] (L = tris(2,4-di-tert-butylphenyl) phosphite; x = 1, 2) were synthesized by simple substitution reactions, and were characterized by spectroscopic methods. The monosubstituted ruthenium complex disproportionates in acetone producing a mononuclear ruthenium complex as one of the decomposition products. Single crystal X-ray diffraction analysis established the molecular structure of this new compound. 相似文献
7.
《Saudi Journal of Biological Sciences》2021,28(12):6957-6962
Asthma is a complicated lung disease, which has increased morbidity and mortality rates in worldwide. There is an overlap between asthma pathophysiology and mitochondrial dysfunction and MSCs may have regulatory effect on mitochondrial dysfunction and treats asthma. Therefore, immune-modulatory effect of MSCs and mitochondrial signaling pathways in asthma was studied.After culturing of MSCs and producing asthma animal model, the mice were treated with MSCs via IV via IT. BALf's eosinophil Counting, The levels of IL-4, −5, −13, −25, –33, INF-γ, Cys-LT, LTB4, LTC4, mitochondria genes expression of COX-1, COX-2, ND1, Nrf2, Cytb were measured and lung histopathological study were done.BALf's eosinophils, the levels of IL-4, −5, −13, −25, –33, LTB4, LTC4, Cys-LT, the mitochondria genes expression (COX-1, COX-2, Cytb and ND-1), perivascular and peribronchial inflammation, mucus hyper-production and hyperplasia of the goblet cell in pathological study were significantly decreased in MSCs-treated asthma mice and reverse trend was found about Nrf-2 gene expression, IFN-γ level and ratio of the INF-γ/IL-4.MSC therapy can control inflammation, immune-inflammatory factors in asthma and mitochondrial related genes, and prevent asthma immune-pathology. 相似文献
8.
9.
Biosynthetic pathway evolution needs to consider the evolution of a group of genes that code for enzymes catalysing the multiple chemical reaction steps leading to the final end product. Tryptophan biosynthetic pathway has five chemical reaction steps that are highly conserved in diverse microbial genomes, though the genes of the pathway enzymes show considerable variations in arrangements, operon structure (gene fusion and splitting) and regulation. We use a combined bioinformatic and statistical analyses approach to address the question if the pathway genes from different microbial genomes, belonging to a wide range of groups, show similar evolutionary relationships within and between them. Our analyses involved detailed study of gene organization (fusion/splitting events), base composition, relative synonymous codon usage pattern of the genes, gene expressivity, amino acid usage, etc. to assess inter- and intra-genic variations, between and within the pathway genes, in diverse group of microorganisms. We describe these genetic and genomic variations in the tryptophan pathway genes in different microorganisms to show the similarities across organisms, and compare the same genes across different organisms to find the possible variability arising possibly due to horizontal gene transfers. Such studies form the basis for moving from single gene evolution to pathway evolutionary studies that are important steps towards understanding the systems biology of intracellular pathways. 相似文献
10.
Reactions of a single-cubane cluster [{Rh(cod)}2{MoCl(dtc)}2(μ3-S)4] (cod = 1,5-cyclooctadiene, dtc = diethyldithiocarbamate) with 1 equiv. of L (L = pyrazine, 4,4′-bipyridyl, trans-1,2-bis(4-pyridyl)ethylene) in the presence of 2 equiv. of AgBF4 in CH2Cl2 gave doubly bridged double-cubane clusters [({Rh(cod)}2{Mo(dtc)}2(μ3-S)4)2(μ-L)2][BF4]4, whose structures were determined by the single-crystal X-ray analysis. 相似文献