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61.
Alberto Muñoz Meiling Chu Peter I. Marris Uma S. Sagaram Jagdeep Kaur Dilip M. Shah Nick D. Read 《Molecular microbiology》2014,92(6):1357-1374
MsDef1 and MtDef4 from Medicago spp. are small cysteine‐rich defensins with potent antifungal activity against a broad range of filamentous fungi. Each defensin has a hallmark γ‐core motif (GXCX3–9C), which contains major determinants of its antifungal activity. In this study, the antifungal activities of MsDef1, MtDef4, and peptides derived from their γ‐core motifs, were characterized during colony initiation in the fungal model, Neurospora crassa. These defensins and their cognate peptides inhibited conidial germination and accompanying cell fusion with different potencies. The inhibitory effects of MsDef1 were strongly mediated by the plasma membrane localized sphingolipid glucosylceramide. Cell fusion was selectively inhibited by the hexapeptide RGFRRR derived from the γ‐core motif of MtDef4. Fluorescent labelling of this hexapeptide showed that it strongly bound to the germ tube plasma membrane/cell wall. Using N. crassa expressing the Ca2+ reporter aequorin, MsDef1, MtDef4 and their cognate peptides were each shown to perturb Ca2+ homeostasis in specific and distinct ways, and the disruptive effects of MsDef1 on Ca2+ were mediated by glucosylceramide. Together, our results demonstrate that MsDef1 and MtDef4 differ markedly in their antifungal properties and specific domains within their γ‐core motifs play important roles in their different modes of antifungal action. 相似文献
62.
Kaur P Yousuf S Ansari MA Siddiqui A Ahmad AS Islam F 《Biological trace element research》2003,95(3):247-258
The effect of various doses of sodium tellurite (0.4, 0.8, and 2.0 mg/kg body weight, orally) on the activity of antioxidant
enzymes (glutathione peroxidase, glutathione reductase, glutathione-S-transferase, and catalase) and content of glutathione and thiobarbituric acid reactive substances (TBARSs) in the cerebrum,
cerebellum, and brainstem of male albino mice was studied after 15 d of treatment. All of the doses of tellurium (0.4, 0.8,
and 2.0 mg/kg body weight, orally) have depleted the activity of antioxidant enzymes and the content of glutathione dose dependently
in the cerebrum, cerebellum, and brainstem and it was significant with the dose of 2.0 mg/kg. On the other hand, the 2.0-mg/kg
dose of tellurium has significantly elevated the content of TBARSs in the cerebrum and cerebellum. The 0.8-mg/kg dose of tellurium
has significantly depleted the activities of glutathione peroxidase in the cerebrum and brainstem, glutathione-S-transferase in the cerebrum and cerebellum, catalase in the brainstem, and the content of glutathione in the cerebrum and
cerebellum. In contrast, this dose has significantly elevated the content of TBARSs in the cerebrum and cerebellum. However,
the depletion in the activity of glutathione reductase with various doses of sodium tellurite was not significant in any brain
part of mice. The result suggests that sodium tellurite differentially affects the antioxidant status within various parts
of the mice brain. 相似文献
63.
Jashanpreet Kaur Shu Yao Duan Lea A. I. Vaas Anahit Penesyan Wieland Meyer Ian T. Paulsen Helena Nevalainen 《PloS one》2015,10(3)
Genotyping studies of Australian Scedosporium isolates have revealed the strong prevalence of a recently described species: Scedosporium aurantiacum. In addition to occurring in the environment, this fungus is also known to colonise the respiratory tracts of cystic fibrosis (CF) patients. A high throughput Phenotype Microarray (PM) analysis using 94 assorted substrates (sugars, amino acids, hexose-acids and carboxylic acids) was carried out for four isolates exhibiting different levels of virulence, determined using a Galleria mellonella infection model. A significant difference was observed in the substrate utilisation patterns of strains displaying differential virulence. For example, certain sugars such as sucrose (saccharose) were utilised only by low virulence strains whereas some sugar derivatives such as D-turanose promoted respiration only in the more virulent strains. Strains with a higher level of virulence also displayed flexibility and metabolic adaptability at two different temperature conditions tested (28 and 37°C). Phenotype microarray data were integrated with the whole-genome sequence data of S. aurantiacum to reconstruct a pathway map for the metabolism of selected substrates to further elucidate differences between the strains. 相似文献
64.
The present investigation was undertaken to identify the possible mode of mechanism that could provide tolerance to maize (Zea mays L.) seedlings under waterlogging. Using cup method, a number of maize genotypes were screened on the basis of survival of the seedlings kept under waterlogging. Two tolerant (LM5 and Parkash) and three susceptible (PMH2, JH3459 and LM14) genotypes were selected for the present study. Activities of antioxidant and ethanolic fermentation enzymes and content of hydrogen peroxide (H2O2), glutathione and ascorbic acid were determined in roots of these genotypes after 72 h of waterlogging. Waterlogging treatment caused decline in activities of superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) in all the genotypes. However, only susceptible genotypes showed slight increase in glutathione reductase (GR) activity. Significant reduction in APX/GR ratio in susceptible genotypes might be the cause of their susceptibility to waterlogging. The tolerant seedlings had higher GR activity than susceptible genotypes under unstressed conditions. Stress led to decrease in H202 and increase in glutathione content of both tolerant and susceptible genotypes, but only tolerant genotypes exhibited increase in ascorbic acid under waterlogging conditions. In the tolerant genotypes, all the enzymes of anaerobic metabolism viz. alcohol dehydrogenase (ADH), aldehyde dehydrogenase (ALDH) and pyruvate decarboxylase (PDC) were upregulated under waterlogging, whereas in susceptible genotypes, only ADH was upregulated, suggesting that efficient upregulation of entire anaerobic metabolic machinery is essential for providing tolerance against waterlogging. The study provides a possible mechanism for waterlogging tolerance in maize. 相似文献
65.
66.
Singh AK Parshad R Pasi S Madhavan T Das SN Mishra B Gill K Dalal K Dey S 《DNA and cell biology》2011,30(10):801-807
Cyclooxygenase-2 (COX-2), an inducible enzyme, has been implicated in the progression and angiogenesis of breast cancer. The aim of the study is to quantify the concentration of COX-2 and its association with clinico-pathological parameters and response to treatment in patients with invasive ductal carcinoma receiving both neo-adjuvant and adjuvant chemotherapy. The level of COX-2 was estimated using a novel biosensor-based surface plasmon resonance technique in serum of 84 patients with breast cancer (48 patients of neo-adjuvant chemotherapy and 36 patients of adjuvant chemotherapy) and 40 age- and gender-matched normal individuals. A significant increase in COX-2 level was observed in patients compared with normal individuals (p>0.0001). The COX-2 level in serum was found to be significantly higher in patients with lymph node involvement (p<0.0061). 68% (33/48) of the patients receiving neo-adjuvant chemotherapy showed significantly (p<0.0025) reduced COX-2 levels. This study shows significant decrease of COX-2 level in patients with breast cancer treated with both neo-adjuvant and adjuvant chemotherapy. Estimation of COX-2 level in serum may serve as a tumor biomarker in patients with breast cancer. 相似文献
67.
68.
Jain S Jain RK McCouch SR 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2004,109(5):965-977
Genetic relationships among Indian aromatic and quality rice (Oryza sativa) germplasm were assessed using 30 fluorescently labeled rice microsatellite markers. The 69 rice genotypes used in this study included 52 Basmati and other scented/quality rice varieties from different parts of India and 17 indica and japonica varieties that served as controls. A total of 235 alleles were detected at the 30 simple sequence repeat (SSR) loci, 62 (26.4%) of which were present only in Basmati and other scented/quality rice germplasm accessions. The number of alleles per locus ranged from 3 to 22, with an average of 7.8, polymorphism information content (PIC) values ranged from 0.2 to 0.9, with an average of 0.6, and the size range between the smallest and the largest allele for a given microsatellite locus varied between 3 bp and 68 bp. Of the 30 SSR markers, 20 could distinguish traditional Basmati rice varieties, and a single panel of eight markers could be used to differentiate the premium traditional Basmati, cross-bred Basmati, and non-Basmati rice varieties having different commercial value in the marketplace. When estimates of inferred ancestry or similarity coefficients were used to cluster varieties, the high-quality Indian aromatic and quality rice genotypes could be distinguished from both indica and japonica cultivars, and crossbred varieties could be distinguished from traditional Basmati rices. The results indicate that Indian aromatic and quality germplasm is genetically distinct from other groups within O. sativa and is the product of a long, independent pattern of evolution. The data also suggest that there is scope for exploiting the genetic diversity of aromatic/quality rice germplasm available in India for national Basmati rice breeding programs.Electronic Supplementary Material Supplementary material is available for this article at . 相似文献
69.
Renu Deswal Ravi Gupta Vivek Dogra Raksha Singh Jasmeet Kaur Abat Abhijit Sarkar Yogesh Mishra Vandana Rai Yelam Sreenivasulu Ramesh Sundar Amalraj Manish Raorane Ram Prasad Chaudhary Ajay Kohli Ashok Prabhakar Giri Niranjan Chakraborty Sajad Majeed Zargar Vishwanath Prasad Agrawal Ganesh Kumar Agrawal Dominique Job Jenny Renaut Randeep Rakwal 《Physiology and Molecular Biology of Plants》2013,19(4):461-477
Plant proteomics has made tremendous contributions in understanding the complex processes of plant biology. Here, its current status in India and Nepal is discussed. Gel-based proteomics is predominantly utilized on crops and non-crops to analyze majorly abiotic (49 %) and biotic (18 %) stress, development (11 %) and post-translational modifications (7 %). Rice is the most explored system (36 %) with major focus on abiotic mainly dehydration (36 %) stress. In spite of expensive proteomics setup and scarcity of trained workforce, output in form of publications is encouraging. To boost plant proteomics in India and Nepal, researchers have discussed ground level issues among themselves and with the International Plant Proteomics Organization (INPPO) to act in priority on concerns like food security. Active collaboration may help in translating this knowledge to fruitful applications. 相似文献
70.