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121.
As PCR methods have improved over the last 15 years, there has been an upsurge in the number of new DNA marker tools, which has allowed the generation of high-density molecular maps for all the key Brassica crop types. Biotechnology and molecular plant breeding have emerged as a significant tool for molecular understanding that led to a significant crop improvement in the Brassica napus species. Brassica napus possess a very complicated polyploidy-based genomics. The quantitative trait locus (QTL) is not sufficient to develop effective markers for trait introgression. In the coming years, the molecular marker techniques will be more effective to determine the whole genome impairing desired traits. Available genetic markers using the single-nucleotide sequence (SNP) technique and high-throughput sequencing are effective in determining the maps and genome polymorphisms amongst candidate genes and allele interactions. High-throughput sequencing and gene mapping techniques are involved in discovering new alleles and gene pairs, serving as a bridge between the gene map and genome evaluation. The decreasing cost for DNA sequencing will help in discovering full genome sequences with less resources and time. This review describes (1) the current use of integrated approaches, such as molecular marker technologies, to determine genome arrangements and interspecific outcomes combined with cost-effective genomes to increase the efficiency in prognostic breeding efforts. (2) It also focused on functional genomics, proteomics and field-based breeding practices to achieve insight into the genetics underlying both simple and complex traits in canola.  相似文献   
122.
HIV gp41(24-157) unfolds cooperatively over the pH range of 1.0-4.0 with T(m) values of > 100 degrees C. At pH 2.8, protein unfolding was 80% reversible and the DeltaH(vH)/DeltaH(cal) ratio of 3.7 is indicative of gp41 being trimeric. No evidence for a monomer-trimer equilibrium in the concentration range of 0.3-36 micro m was obtained by DSC and tryptophan fluorescence. Glycosylation of gp41 was found to have only a marginal impact on the thermal stability. Reduction of the disulfide bond or mutation of both cysteine residues had only a marginal impact on protein stability. There was no cooperative unfolding event in the DSC thermogram of gp160 in NaCl/P(i), pH 7.4, over a temperature range of 8-129 degrees C. When the pH was lowered to 5.5-3.4, a single unfolding event at around 120 degrees C was noted, and three unfolding events at 93.3, 106.4 and 111.8 degrees C were observed at pH 2.8. Differences between gp41 and gp160, and hyperthermostable proteins from thermophile organisms are discussed. A series of gp41 mutants containing single, double, triple or quadruple point mutations were analysed by DSC and CD. The impact of mutations on the protein structure, in the context of generating a gp41 based vaccine antigen that resembles a fusion intermediate state, is discussed. A gp41 mutant, in which three hydrophobic amino acids in the gp41 loop were replaced with charged residues, showed an increased solubility at neutral pH.  相似文献   
123.
BotXIV and LqhalphaIT are two structurally related long chain scorpion alpha-toxins that inhibit sodium current inactivation in excitable cells. However, while LqhalphaIT from Leiurus quinquestriatus hebraeus is classified as a true and strong insect alpha-toxin, BotXIV from Buthus occitanus tunetanus is characterized by moderate biological activities. To assess the possibility that structural differences between these two molecules could reflect the localization of particular functional topographies, we compared their sequences. Three structurally deviating segments located in three distinct and exposed loops were identified. They correspond to residues 8-10, 19-22, and 38-43. To evaluate their functional role, three BotXIV/LqhalphaIT chimeras were designed by transferring the corresponding LqhalphaIT sequences into BotXIV. Structural and antigenic characterizations of the resulting recombinant chimera show that BotXIV can accommodate the imposed modifications, confirming the structural flexibility of that particular alpha/beta fold. Interestingly, substitution of residues 8-10 yields to a new electrophysiological profile of the corresponding variant, partially comparable to that one of alpha-like scorpion toxins. Taken together, these results suggest that even limited structural deviations can reflect functional diversity, and also that the structure-function relationships between insect alpha-toxins and alpha-like scorpion toxins are probably more complex than expected.  相似文献   
124.
Modulation of water relations, activities of antioxidant enzymes and ion accumulation was assessed in the plants of two wheat cultivars S-24 (salt tolerant) and MH-97 (moderately salt sensitive) subjected to saline conditions and glycinebetaine (GB) applied foliarly. Different levels of GB, i.e., 0 (unsprayed), 50 and 100 mM (in 0.10% Tween-20 solution) were applied to the wheat plants at the vegetative growth stage. Leaf water potential, leaf osmotic potential and turgor potential were decreased due to salt stress. Salt stress increased the Na+ and Cl accumulation coupled with a decrease in K+ and Ca2+ in the leaves and roots of both cultivars thereby decreasing tissue K+/Na+ and Ca2+/Na+ ratios. Furthermore, salt stress decreased the activities of superoxide dismutase (SOD), whereas it increased the activities of catalase (CAT) and peroxidase (POD) in both wheat cultivars. However, accumulation of GB in the leaves of both wheat cultivars was consistently increased with an increase in concentration of exogenous GB application under both non-saline and saline conditions. Accumulation of Na+ was decreased with an increase in K+ accumulation upon a consistent increase in GB accumulation under salt stress conditions thereby resulting in better K+/Na+ and Ca2+/Na+ ratios in the leaves and roots. High accumulation of GB and K+ mainly contributed to osmotic adjustment, which is one of the factors known to be responsible for improving growth and yield under salt stress. The activities of all antioxidant enzymes, SOD, CAT and POD were enhanced by GB application in cv. MH-97 under saline conditions, whereas all these except SOD were reduced in cv. S-24. It is likely that both applied GB and intrinsic SOD scavenged ROS in the tolerant cultivar thereby resulting into low activities of CAT and POD enzymes under salt stress. In conclusion, the adverse effects of salt stress on wheat can be alleviated by the exogenous application of 100 mM GB by modulating activities of antioxidant enzymes and changes in water relations and ion homeostasis. Furthermore, effectiveness of GB application on regulation of activities of antioxidant enzymes was found to be cultivar-specific.  相似文献   
125.
Reproductive success is crucial for the survival and persistence of any species. The Deccan Biogeographic Zone of India is the stronghold of a population of the Indian wolf Canis lupus pallipes . Gaining a better understanding of the den-use pattern of wolves in different areas in this zone is thus vital for their conservation and management. The wolves excavated multiple dens in our study sites and kept shifting their litters among them. Major disturbance factors around denning sites were active stone quarries, traffic, crop harvesting and livestock movement. One wolf pack used 14 dens in four breeding seasons. Discriminant function analysis indicated that den shifting by wolves was not entirely governed by disturbance levels at den sites. Increasing age of pups was one of the main factors associated with den shifting rather than the magnitude of disturbance ( χ 2=34.26, d.f.=12, P <0.001). Tolerance to disturbance around dens during the early stages of pup development was negatively correlated ( r =−0.519, P <0.05) with availability of water and age of pups ( r =−0.613, P <0.01). Excavation of multiple dens by wolves was apparently related to den shifting, which seemingly is a survival strategy of wolves in these semi-wild human-dominated landscapes in the Deccan Biogeographic Zone. Principal components analysis indicated that during the initial stages of pup development, nature of the land, den orientation and distance of the den from roads were important cues in addition to age category of pups for den shifting. The analysis also suggested that factors such as distance of the new den where pups are to be transferred, distance from water source and availability of fox Vulpes bengalensis holes for den use were also important.  相似文献   
126.
Increasing emphasis has been recently put on large-scale network processing of brain functions. To explore these networks, many approaches have been proposed in functional magnetic resonance imaging (fMRI). Their objective is to answer the following two questions: (1) what brain regions are involved in the functional process under investigation? and (2) how do these regions interact? We review some of the key concepts and corresponding methods to cope with both issues.  相似文献   
127.
128.
A novel actinomycete, designated strain YIM CF22T, was isolated from a desert soil sample collected from Turpan in Xinjiang Uyghur Autonomous Region, north-western China. The taxonomic position of the strain YIM CF22T is described based on a polyphasic approach. Strain YIM CF22T was found to form irregular sporangia on agar media. It contains meso-diaminopimelic acid in the cell wall peptidoglycan. The major menaquinone was identified as MK-9(H4); the polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, two unidentified phospholipids and two unidentified glycolipids. The whole cell sugars were found to be ribose, mannose, galactose, glucose and xylose. The major cellular fatty acids were found to be (>?5%) iso-C16:0 (43.5%), anteiso-C17:0 (10.2%), iso-C15:0 (7.1%), C17:1 ω8c (6.3%) and iso H-C16:1 (5.9%). The G+C content was determined to be 70.8%. 16S rRNA gene sequence analysis of strain YIM CF22T showed high similarity (97.0%) to Actinoplanes rishiriensis NBRC 108556T. The strain also showed high 16S rRNA gene sequence similarities to Verrucosispora sediminis CGMCC 4.3550T (96.9%) and Micromonospora tulbaghiae DSM 45142T (96.8%). Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain YIM CF22T clusters with A. rishiriensis NBRC 108556T, Actinoplanes globisporus JCM 3186T and Actinoplanes rhizophilus NEAU-A-2T. Based on the differential phenotypic characteristics and the results of DNA–DNA relatedness and phylogenetic analysis, it is proposed that strain YIM CF22T represents a novel species of the genus Actinoplanes, for which the name Actinoplanes deserti sp. nov. is proposed. The type strain is YIM CF22T (=?KCTC 39543T?=?CCTCC AB2018113T).  相似文献   
129.
130.
An association between a hypercoagulable state and Mendelian susceptibility to mycobacterial disease (MSMD) has been established in a few studies; resultant thrombosis is considered rare. In a case‐control study, the prevalence of factor V Leiden, prothrombin G20210A and methylenetetrahydrofolate reductase (MTHFR) C677T, A1298C mutations were investigated in mycobacterium‐infected patients. The study comprised 30 patients with mycobacterial infections (invasive, disseminated and/or recurrent infections with Bacille Calmette–Guerin or non‐tuberculosis mycobacteria and Mycobacterium Tuberculosis with positive results for acid‐fast bacilli and tuberculin skin tests) and 30 normal healthy controls. Forty female (66.7%) and 20 male subjects (33.3%) aged from 3 to 70 years were recruited into this study. Genotyping of targeted genes was performed by RT‐PCR and cytokine TNF‐α concentrations were quantified using a commercially available ELISA kit. Significant associations between mycobacterial infection and TNF‐α production after stimulating peripheral blood mononuclear cells with LPS alone and with IFN‐γ plus LPS were identified. Moreover, genotyping analysis in the studied population revealed a significant association between MTHFR c.677C>T (OR, 3.28; 95% CI, 1.35–7.92; P < 0.05), MTHFR c.1298A>C (OR, 2.33; 95% CI, 1.10–4.93; P < 0.05) and mycobacterial infection in affected patients, indicating susceptibility to venous thromboembolism according to previous studies. Additionally, mycobacterium‐infected patients had a significantly greater prevalence of MTHFR C677T and A1298C mutations than controls.  相似文献   
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