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481.
482.
Jing Zhang Yingzi Yun Yi Lou Yakubu Saddeeq Abubakar Pusheng Guo Shumin Wang Chunling Li Yuan Feng Muhammad Adnan Jie Zhou Guo‐dong Lu Wenhui Zheng 《Cellular microbiology》2019,21(8)
AP‐2 complex is widely distributed in eukaryotes in the form of heterotetramer that functions in the uptake of membrane proteins during mammalian/plant clathrin‐mediated endocytosis. However, its biological function remains mysterious in pathogenic fungi. In this study, the wheat scab fungus, Fusarium graminearum, was used to characterise the biological function of the AP‐2 complex. Our study shows that FgAP‐2 complex plays a critical role in the maintenance of hyphal polarity. Lack of any subunit (FgAP2α, FgAP2β, FgAP2σ, and FgAP2mu) of the FgAP‐2 complex significantly affects the fungal vegetative growth, conidial morphology, and germination. Remarkably, FgAP‐2 complex is important for the fungal pathogenicity, especially during colonisation and extension after infecting the host. The FgAP‐2 complex is expressed ubiquitously at all developmental stages but having more concentrated protein distribution at the subapical collar and septa in young growing hyphae. Although FgAP‐2 complex displays similar dynamic behaviour to the actin patch components and accumulates at endocytic sites, it is dispensable for general endocytosis. We further demonstrated that FgAP‐2 complex is required for polar localisation of the lipid flippases FgDnfA and FgDnfB, which led to the proposal that FgAP‐2 functions as a cargo‐specific adaptor that promotes polar growth and colonising ability of F. graminearum. 相似文献
483.
Muhammad Nadeem Waqar Ahmad Adnan Zahir Christophe Hano Bilal Haider Abbasi 《Engineering in Life Science》2019,19(3):168-174
Linum usitatsimum L. (flax) is a perennial herb with magnitude of medicinal and commercial applications. In the present study, we investigated the effects of salicylic acid (SA) on biosynthesis of lignans (secoisolariciresinol diglucoside (SDG) and lariciresinol diglucoside (LDG)) and neolignans (dehydrodiconiferyl alcohol glucoside (DCG) and guaiacylglycerol‐β‐coniferyl alcohol ether glucoside (GGCG)) in cell cultures of flax. Moderate concentration of SA (50 μM) enhanced biomass accumulation (10.98 g/L dry weight (DW)), total phenolic content (37.81 mg/g DW), and antioxidant potential (87.23%) to two‐fold than their respective controls after 72 h of exposure. However, higher levels of total flavonoid content (5.32 mg/g DW) were noted after 48 h of exposure to 50 μM of SA. HPLC analyses revealed that 50 μM SA, significantly enhanced biosynthesis of SDG (7.95 mg/g DW), LDG (7.52 mg/g DW), DCG (54.90 mg/g DW), and GGCG (16.78 mg/g DW), which was almost 2.7, 1.8, 3.88, and 3.98 fold higher than their respective controls after 72 h of exposure time, respectively. These results indicated that moderate concentrations of SA had significant effects on biosynthesis and productivity of lignans and neolignans in cell culture of L. usitatissimum. 相似文献
484.
Abd El-Fattah Adnan Dababat Richard Alexander Sikora 《Biocontrol Science and Technology》2007,17(9):969-975
The non-pathogenic endophytic fungus, Fusarium oxysporum strain 162, originally isolated from the endorhiza of tomato roots, reduces damage caused by Meloidogyne incognita, by inhibiting juvenile penetration of and development in the root. However, little is known about the mode of action of this endophyte fungus against the nematode. This study aimed at investigating how the endophyte affects nematode motility and survival and if induced resistance plays a role in the relationship. In a previous study, F. oxysporum strain 162 decreased nematode penetration of tomato up to 60%. In experiments using a split-root chamber to test for induced resistance, nematode penetration, number of galls, and number of egg masses were investigated 2 and 5 weeks after nematode inoculation. Split-root plants treated with F. oxysporum strain 162 showed 26-45% less nematode penetration, 21-36% less galls and a 22-26% reduction in the number of egg masses in the roots not directly inoculated with the fungus when compared to untreated control plants in repeated tests. In conclusion, inoculation of tomato plants with the non-pathogenic fungal endophyte F. oxysporum strain 162 resulted in a signficant reduction of nematode infection, which was in part due to induced resistance in the first 2-3 weeks after fungal inoculation. 相似文献
485.
Salman Abdo Al-Shami Che Salmah Md Rawi Suhaila Abdul Hamid Nurul Huda Abdul Mariam Zhafarina Rusli Wan Nur Asiah Wan Mohd Adnan Nur Adibah Mohd Ishadi Mohd Shafiq Zakeyuddin Sanya Abdulkareem Al-Qormuti Khalid A. Al-Mutairi Yap Chee Kong 《农业工程》2021,41(1):50-56
The loss of aquatic biodiversity in tropical streams of SE Asia is evident due to increasing anthropogenic activities. Therefore, there is a necessity for immediate and feasible conservation plans. Effective conservation planning depends on successful application of surrogate groups. However, progress of this approach is hindered by the paucity of relevant reports based on cross-taxon congruence analysis. In this study, we investigated congruence patterns among aquatic groups (Plecoptera, Trichoptera, Ephemeroptera, Odonata and fish) in six rivers located in the Kerian River Basin (KRB), Malaysia. Species richness was significantly correlated among aquatic groups (except for Ephemeroptera and Trichoptera where r = 0.040 and P = 0.202). The strongest relationship in species richness was reported between Ephemeroptera and Plecoptera. The Mantel's r coefficient of similarity matrices (based on the Bray-Curtis distance measure) showed a positive correlation between the matrices of Ephemeroptera-Trichoptera and Plecoptera-Trichoptera. However, a negative relationship was reported between Odonata-fish matrices. The relationships between average Trichoptera-Odonata distance to the centroid (i.e. beta diversity) among the aquatic groups were also investigated. The strongest relationship in the average to the centroids was reported between Ephemeroptera and Odonata (R2 = 0.424, P < 0.05). However, the weakest relationship was reported between Trichoptera and fish with R2 value of 0.024. It is concluded that richness of Plecoptera, Odonata and fish showed correlations patterns, and these can be used as surrogates for each other with some restrictions. 相似文献
486.
Toxoplasma gondii is an obligate intracellular protozoan which infects one-third of the human population. Due to its high infection prevalence, Toxoplasma offers an ideal system for the study of host–parasite interaction. Similar to other eukaryotes, Toxoplasma maintains levels and localization of cytoplasmic mRNAs throughout its life cycle as part of a gene regulation network to meet all cellular and biochemical requirements. More recently, it was reported that the presence of cytoplasmic mRNA granules could contribute to the parasite pathogenesis and viability. Here we identified a novel Toxoplasma DEAD-box RNA helicase, referred to as Toxoplasma gondiiHomolog of DOZI (TgHoDI), because of its high homology (81%) to Plasmodium DOZI. TgHoDI is the functional ortholog of yeast DHH1, and its function was authenticated by complementation studies in Δdhh1 yeast strain. We demonstrated that TgHoDI is a marker of cytoplasmic RNA stress granules, which assemble when the parasites experience cellular stresses and translational arrest. 相似文献
487.
Key Message
Efficient induction of unreduced gamete in different crops and its genetic consequences will open new avenues for plant breeding.Abstract
Unreduced gamete formation derived via abnormal meiotic cell division is an important approach to polyploidy breeding. This process is considered the main driving force in spontaneous polyploids formation in nature, but the potential application of these gametes to plant breeding has not been fully exploited. An effective mechanism for their artificial induction is needed to attain greater genetic variation and enable efficient use of unreduced gametes in breeding programs. Different approaches have been employed for 2n-pollen production including interspecific hybridization, manipulation of environmental factors and treatment with nitrous oxide, trifluralin, colchicine, oryzalin and other chemicals. These chemicals can act as a stimulus to produce viable 2n pollen; however, their exact mode of action, optimum concentration and developmental stages are still not known. Identification of efficient methods of inducing 2n-gamete formation will help increase pollen germination of sterile interspecific hybrids for inter-genomic recombination and introgression breeding to develop new polyploid cultivars and increase heterozygosity among plant populations. Additionally, the application of genomic tools and identification and isolation of genes and mechanisms involved in the induction of 2n-gamete will enable increased exploitation in different plant species, which will open new avenues for plant breeding. 相似文献488.
High dimensionality and small sample sizes, and their inherent risk of overfitting, pose great challenges for constructing efficient classifiers in microarray data classification. Therefore a feature selection technique should be conducted prior to data classification to enhance prediction performance. In general, filter methods can be considered as principal or auxiliary selection mechanism because of their simplicity, scalability, and low computational complexity. However, a series of trivial examples show that filter methods result in less accurate performance because they ignore the dependencies of features. Although few publications have devoted their attention to reveal the relationship of features by multivariate-based methods, these methods describe relationships among features only by linear methods. While simple linear combination relationship restrict the improvement in performance. In this paper, we used kernel method to discover inherent nonlinear correlations among features as well as between feature and target. Moreover, the number of orthogonal components was determined by kernel Fishers linear discriminant analysis (FLDA) in a self-adaptive manner rather than by manual parameter settings. In order to reveal the effectiveness of our method we performed several experiments and compared the results between our method and other competitive multivariate-based features selectors. In our comparison, we used two classifiers (support vector machine, -nearest neighbor) on two group datasets, namely two-class and multi-class datasets. Experimental results demonstrate that the performance of our method is better than others, especially on three hard-classify datasets, namely Wang''s Breast Cancer, Gordon''s Lung Adenocarcinoma and Pomeroy''s Medulloblastoma. 相似文献
489.
Mattia CF Prosperi Susana Marinho Angela Simpson Adnan Custovic Iain E Buchan 《BMC medical genomics》2014,7(Z1):S7
Background
There is increasing recognition that asthma and eczema are heterogeneous diseases. We investigated the predictive ability of a spectrum of machine learning methods to disambiguate clinical sub-groups of asthma, wheeze and eczema, using a large heterogeneous set of attributes in an unselected population. The aim was to identify to what extent such heterogeneous information can be combined to reveal specific clinical manifestations.Methods
The study population comprised a cross-sectional sample of adults, and included representatives of the general population enriched by subjects with asthma. Linear and non-linear machine learning methods, from logistic regression to random forests, were fit on a large attribute set including demographic, clinical and laboratory features, genetic profiles and environmental exposures. Outcome of interest were asthma, wheeze and eczema encoded by different operational definitions. Model validation was performed via bootstrapping.Results
The study population included 554 adults, 42% male, 38% previous or current smokers. Proportion of asthma, wheeze, and eczema diagnoses was 16.7%, 12.3%, and 21.7%, respectively. Models were fit on 223 non-genetic variables plus 215 single nucleotide polymorphisms. In general, non-linear models achieved higher sensitivity and specificity than other methods, especially for asthma and wheeze, less for eczema, with areas under receiver operating characteristic curve of 84%, 76% and 64%, respectively. Our findings confirm that allergen sensitisation and lung function characterise asthma better in combination than separately. The predictive ability of genetic markers alone is limited. For eczema, new predictors such as bio-impedance were discovered.Conclusions
More usefully-complex modelling is the key to a better understanding of disease mechanisms and personalised healthcare: further advances are likely with the incorporation of more factors/attributes and longitudinal measures.490.