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11.
Amrita Saxena Richa Raghuwanshi Harikesh Bahadur Singh 《Journal of Plant Growth Regulation》2016,35(2):377-389
Biocontrol strategies have been mainly focused on proposing the use of biocontrol agents (BCAs) isolated from the rhizospheric region of the plant for protection against phytopathogens. The present study evaluates the effectiveness of phyllospheric Trichoderma isolates in elevating the defense responses in chilli against Colletotrichum capsici infection and comparing its efficiency to the conventionally recommended rhizospheric Trichoderma strains. The elicitation of the defense network in the plants was analyzed using biochemical assays for important enzymes, that is, PAL, PO, PPO, TPC, SOD along with the total protein level in challenged plants over untreated and unchallenged control plants. The results recorded 2.1, 5.18, 3, 0.67, and 0.5-fold increases in TPC, PAL, PO, PPO, and total protein content in BHUF4 (phyllopsheric Trichoderma isolate)-treated plants when compared to control plants under C. capsici challenge. This was at par with the increment recorded in T16A (rhizospheric Trichoderma isolate)-treated chilli plants. The increment in growth parameters was also recorded after treatment with the isolated Trichoderma strains. Interestingly, the phyllospheric isolate (BHUF4) treatment recorded comparable growth promotion in chilli plants recording 36, 62, and 60 % increases in one of the major parameters of plant growth, that is, root length, no. of leaves, and dry weight, respectively. This study proposes the use of combined application of both rhizospheric as well as phyllospheric Trichoderma isolates for better and all around protection of plants against foliar as well as soil phytopathogens. This would be a novel approach in biological control strategy for better management of anthracnose disease of chilli. 相似文献
12.
Akansha Saxena Kumar Parijat Tripathi Sudeep Roy Feroz Khan Ashok Sharma 《Bioinformation》2008,3(5):198-204
Cytochrome P450 (CYP P450) enzymes are a superfamily of mono-oxygenases that are found in all kingdoms of life. The CYP P450 enzymes constitute a large superfamily of haem-thiolate proteins involved in the metabolism of a wide variety of both exogenous and endogenous compounds. The CYP activities have been shown to be involved in numerous interactions especially between drugs and herbal constituents. The majority of serious cases of drug interactions are as a result of the interference of the metabolic clearance of one drug by yet another co-administered drug, food or natural product. Gaining mechanistic knowledge towards such interactions has been accepted as an approach to avoid adverse reactions. The inductions and inhibition of CYP enzymes by natural products in the presence of a prescribed drug has led to adverse effects. Herbal medicines such as St. John's wort (Hypericum perforatum), garlic (Allium sativa), piperine (from Piper sp.), ginseng (Ginseng sp.), gingko (Gingko biloba), soya beans (Glycine max), alfalfa (Medicago sativa) and grape fruit juice show clinical interactions when co-administered with medicines. This review documents the involvement of CYP enzymes in the metabolism of known available drugs and herbal products. We also document the interactions between herbal constituents & CYP enzymes showing potential drug-herb interactions. Data on CYP450 enzymes in activation (i.e. induction or inhibition) with natural constituents is also reviewed. 相似文献
13.
Helms MN Liu L Liang YY Al-Khalili O Vandewalle A Saxena S Eaton DC Ma HP 《The Journal of biological chemistry》2005,280(49):40885-40891
Whole cell voltage clamp experiments were performed in a mouse cortical collecting duct principal cell line using patch pipettes back-filled with a solution containing phosphatidylinositol 3,4,5-trisphosphate (PIP(3)). PIP(3) significantly increased amiloridesensitive current in control cells but not in the cells prestimulated by aldosterone. Additionally, aldosterone stimulated amiloridesensitive current in control cells, but not in the cells that expressed a PIP(3)-binding protein (Grp1-PH), which sequestered intracellular PIP(3). 12 amino acids from the N-terminal tail (APGEKIKAKIKK) of gamma-epithelial sodium channel (gamma-ENaC) were truncated by PCRbased mutagenesis (gammaT-ENaC). Whole cell and confocal microscopy experiments were conducted in Madin-Darby canine kidney cells co-expressing alpha- and beta-ENaC only or with either gamma-ENaC or gamma(T)-ENaC. The data demonstrated that the N-terminal tail truncation significantly decreased amiloride-sensitive current and that both the N-terminal tail truncation and LY-294002 (a PI3K inhibitor) prevented ENaC translocation to the plasmamembrane. These data suggest that PIP(3) mediates aldosterone-induced ENaC activity and trafficking and that the N-terminal tail of gamma-ENaC is necessary for channel trafficking, probably channel gating as well. Additionally, we demonstrated a novel interaction between gamma-ENaC and PIP(3). 相似文献
14.
Hypothalamic LHRH, pituitary LH and plasma LH levels were measured in rats of both sexes from day 5-60 after birth. The content of hypothalamic LHRH was very high in one-week-old male and female rats. It declined gradually till day 17 in the female rat and sharply on day 10 in the male rat. Subsequently the content of hypothalamic LHRH increased and showed peak values on day 25 in the female rat and on day 45 in the male rat. It decreased markedly at respective times of puberty in both sexes (day 37 in the female rat and day 52-60 in the male rat). Results of the study suggest that maturation of hypothalamo-hypophyseal-axis proceeds in three distinct stages. Observations on days 17, 25 and 37 in the female rat and on days 5, 7, 10 and 22 in the male rat clearly show an inverse relationship between hypothalamic LHRH and plasma LH and a parallel relationship between pituitary and plasma LH. Marked decline in the content of hypothalamic LHRH at respective times of puberty in both sexes indicates that the release of threshold levels of LHRH from the hypothalamus may apparently be the event initiating the pubertal changes in rat. 相似文献
15.
16.
Incorporation of photosynthetically fixed 14C was studied at different time intervals of 12, 24, and 36 h in various plant parts—leaf 1 to 4 from apex, roots, and rhizome—into primary metabolites—sugars, amino acids, and organic acids, and secondary metabolites—essential oil and curcumin—in turmeric. The youngest leaves were most active in fixing 14C at 24 h. Fixation capacity into primary metabolites decreased with leaf position and time. The primary metabolite levels in leaves were maximal in sugars and organic acids and lowest in amino acids. Roots as well as rhizome received maximum photoassimilate from leaves at 24 h; this declined with time. The maximum metabolite concentrations in the roots and rhizome were high in sugars and organic acids and least in amino acids. 14C incorporation into oil in leaf and into curcumin in rhizome was maximal at 24 h and declined with time. These studies highlight importance of time-dependent translocation of 14C-primary metabolites from leaves to roots and rhizome and their subsequent biosynthesis into secondary metabolite, curcumin, in rhizome. This might be one of factors regulating the secondary metabolite accumulation and rhizome development. 相似文献
17.
Reshu Saxena Sudipti Gupta Kavita Singh Kalyan Mitra Anil Kumar Tripathi Raj Kamal Tripathi 《PloS one》2015,10(4)
Nef is an accessory viral protein that promotes HIV-1 replication, facilitating alterations in cellular pathways via multiple protein-protein interactions. The advent of proteomics has expanded the focus on better identification of novel molecular pathways regulating disease progression. In this study, nef was sequenced from randomly selected patients, however, sequence variability identified did not elicited any specific mutation that could have segregated HIV-1 patients in different stages of disease progression. To explore the difference in Nef functionality based on sequence variability we used proteomics approach. Proteomic profiling was done to compare the effect of Nef variants in host cell protein expression. 2DGE in control and Nef transfected SupT1 cells demonstrated several differentially expressed proteins. Fourteen protein spots were detected with more than 1.5 fold difference. Significant down regulation was seen in six unique protein spots in the Nef treated cells. Proteins were identified as Cyclophilin A, EIF5A-1 isoform B, Rho GDI 1 isoform a, VDAC1, OTUB1 and α-enolase isoform 1 (ENO1) through LC-MS/MS. The differential expression of the 6 proteins was analyzed by Real time PCR, Western blotting and Immunofluorescence studies with two Nef variants (RP14 and RP01) in SupT1 cells. There was contrasting difference between the effect of these Nef variants upon the expression of these six proteins. Downregulation of α-enolase (ENO1), VDAC1 and OTUB1 was more significant by Nef RP01 whereas Cyclophilin A and RhoGDI were found to be more downregulated by Nef RP14. This difference in Nef variants upon host protein expression was also studied through a site directed mutant of Nef RP01 (55AAAAAAA61) and the effect was found to be reversed. Deciphering the role of these proteins mediated by Nef variants will open a new avenue of research in understanding Nef mediated pathogenesis. Overall study determines modulation of cellular protein expression in T cells by HIV-1 Nef variants. 相似文献
18.
An in vitro comparative study on the reactivation of nerve agent-inhibited guinea pig and human acetylcholinesterases by oximes 总被引:1,自引:0,他引:1
The reactivation of nerve agent-inhibited acetylcholinesterase (AChE) by oxime is the most important step in the treatment of nerve agent poisoning. Since the evaluation of nerve agent antidotes cannot be conducted in humans, results from animal experiments are extrapolated to humans. Guinea pig is one of the animal models that is frequently used for conducting nerve agent antidote evaluations. Several investigations have demonstrated that the efficacy of an oxime primarily depends on its ability to reactivate nerve agent-inhibited AChE. If the in vitro oxime reactivation of nerve agent-inhibited animal AChE is similar to that of human AChE, it is likely that the results of an in vivo animal study will reliably extrapolate to humans. Therefore, the goal of this study was to compare the reactivation of guinea pig and human AChEs inhibited by six different G and V type nerve agents. Reactivation kinetic studies with five mono- and bis-pyridinium oximes showed that oxime reactivation of nerve agent-inhibited human AChE in most cases was faster than guinea pig AChE. The most significant enhancement was observed in the reactivation of human AChE inhibited by nerve agents containing bulky side chains GF, GD, and VR, by H-series oximes HLo-7, HI-6, and ICD-585. In these cases, species-related differences observed between the two AChEs, based on the second-order reactivation rate constants, were 90- to over 400-fold. On the other hand, less than 3-fold differences were observed in the rates of aging of nerve agent-inhibited guinea pig and human AChEs. These results suggest that the remarkable species-related differences observed in the reactivation of nerve agent-inhibited guinea pig and human AChEs were not due to differences in the rates of aging. These results also suggest that guinea pig may not be an appropriate animal model for the in vivo evaluation of oxime therapy. 相似文献
19.
Subash Chandra Gupta Hifzur Rahman Siddique Neeraj Mathur Achchhe Lal Vishwakarma Ranjit Kishore Mishra Daya Krishna Saxena Debapratim Kar Chowdhuri 《Biochimica et Biophysica Acta (BBA)/General Subjects》2007
We examined a hypothesis that reactive oxygen species (ROS) generated by organophosphate compound dichlorvos modulates Hsp70 expression and anti-oxidant defense enzymes and acts as a signaling molecule for apoptosis in the exposed organism. Dichlorvos (0.015–15.0 ppb) without or with inhibitors of Hsp70, superoxide dismutase (SOD) and catalase (CAT) were fed to the third instar larvae of Drosophila melanogaster transgenic for hsp70 (hsp70-lacZ) Bg9 to examine Hsp70 expression, oxidative stress and apoptotic markers. A concentration- and time-dependent significant increase in ROS generation accompanied by a significant upregulation of Hsp70 preceded changes in antioxidant defense enzyme activities and contents of glutathione, malondialdehyde and protein carbonyl in the treated organisms. An inhibitory effect on SOD and CAT activities significantly upregulated ROS generation and Hsp70 expression in the exposed organism while inhibition of Hsp70 significantly affected oxidative stress markers induced by the test chemical. A comparison made among ROS generation, Hsp70 expression and apoptotic markers showed that ROS generation is positively correlated with Hsp70 expression and apoptotic cell death end points indicating involvement of ROS in the overall adversity caused by the test chemical to the organism. The study suggests that (a) Hsp70 and anti-oxidant enzymes work together for cellular defense against xenobiotic hazard in D. melanogaster and (b) free radicals may modulate Hsp70 expression and apoptosis in the exposed organism. 相似文献
20.
Basic Local Alignment Search Tool (BLAST) is a popular tool used for determining the patterns in genomic sequences. The algorithm of BLAST has gone for various changes from time to time. One third of the time is taken by BLAST to perform the gapped analysis on the sequences. An efficient algorithm has been presented that employs a new approach for curtailing the amount of sequences that proceed for gapped alignment. So this method will work after the ungapped alignment process is over. This works because of the fact that it is not necessary to perform gapped alignment for all the sequences that are coming from ungapped analysis. There is a significant increase in speed of the alignment process without compromising on the sensitivity of the result. 相似文献