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181.
Hassan Ashktorab Hamed Rahi Daniel Wansley Sudhir Varma Babak Shokrani Edward Lee Mohammad Daremipouran Adeyinka Laiyemo Ajay Goel John M Carethers Hassan Brim 《Epigenetics》2013,8(8):807-815
CpG Island Methylator Phenotype (CIMP) is one of the underlying mechanisms in colorectal cancer (CRC). This study aimed to define a methylome signature in CRC through a methylation microarray analysis and a compilation of promising CIMP markers from the literature. Illumina HumanMethylation27 (IHM27) array data was generated and analyzed based on statistical differences in methylation data (1st approach) or based on overall differences in methylation percentages using lower 95% CI (2nd approach). Pyrosequencing was performed for the validation of nine genes. A meta-analysis was used to identify CIMP and non-CIMP markers that were hypermethylated in CRC but did not yet make it to the CIMP genes’ list. Our 1st approach for array data analysis demonstrated the limitations in selecting genes for further validation, highlighting the need for the 2nd bioinformatics approach to adequately select genes with differential aberrant methylation. A more comprehensive list, which included non-CIMP genes, such as APC, EVL, CD109, PTEN, TWIST1, DCC, PTPRD, SFRP1, ICAM5, RASSF1A, EYA4, 30ST2, LAMA1, KCNQ5, ADHEF1, and TFPI2, was established. Array data are useful to categorize and cluster colonic lesions based on their global methylation profiles; however, its usefulness in identifying robust methylation markers is limited and rely on the data analysis method. We have identified 16 non-CIMP-panel genes for which we provide rationale for inclusion in a more comprehensive characterization of CIMP+ CRCs. The identification of a definitive list for methylome specific genes in CRC will contribute to better clinical management of CRC patients. 相似文献
182.
Mahnaz Sadeghi Sara Dehghan Rainer Fischer Uwe Wenzel Andreas Vilcinskas Hamid Reza Kavousi Mohammad Rahnamaeian 《Plant signaling & behavior》2013,8(11)
Salicylic acid (SA) is a prominent signaling molecule during biotic and abiotic stresses in plants biosynthesized via cinnamate and isochorismate pathways. Cinnamate 4-hydroxylase (C4H) and isochorismate synthase (ICS) are the main enzymes in phenylpropanoid and isochorismate pathways, respectively. To investigate the actual roles of these genes in resistance mechanism to environmental stresses, here, the coding sequences of these enzymes in safflower (Carthamus tinctorius), as an oilseed industrial medicinal plant, were partially isolated and their expression profiles during salinity stress, wounding, and salicylic acid treatment were monitored. As a result, safflower ICS (CtICS) and C4H (CtC4H) were induced in early time points after wounding (3–6 h). Upon salinity stress, CtICS and CtC4H were highly expressed for the periods of 6–24 h and 3–6 h after treatment, respectively. It seems evident that ICS expression level is SA concentration dependent as if safflower treatment with 1 mM SA could induce ICS much stronger than that with 0.1 mM, while C4H is less likely to be so. Based on phylogenetic analysis, safflower ICS has maximum similarity to its ortholog in Vitis vinifera up to 69%, while C4H shows the highest similarity to its ortholog in Echinacea angustifolia up to 96%. Overall, the isolated genes of CtICS and CtC4H in safflower could be considered in plant breeding programs for salinity tolerance as well as for pathogen resistance. 相似文献
183.
Dipti Verma Mohammad Wahid Ansari Ganesh Kumar Agrawal Randeep Rakwal Alok Shukla Narendra Tuteja 《Plant signaling & behavior》2013,8(4)
Drought is the major environmental stress that limits rice productivity worldwide. In vitro somaclonal variation using different selection agents has been used for crop improvement. Here, rice plants of cv PR113 were selected in vitro on 30, 50 and 70 g L-1 polyethylene glycol 6,000 (PEG). Callus growth, proliferation, calli volume (first and second culture) and plantlet regeneration (third culture) were found to be decreased upto a certain level to acquire tolerance to PEG-induced drought. From the field data, 30 g L-1 PEG lines showed higher vegetative growth (plant height, tiller number, leaf number, shoot weight and root growth) as compared with 50 g L-1 PEG selected somaclone lines under limited irrigation. The yield parameters-panicle length, panicle weight, grains per panicle, 1,000-grain weight, grain yield per plant, harvest index and grain straw ratio were also higher in 30 g L-1 PEG lines as compared with 50 g L-1 PEG lines. The results, therefore indicate that 30 g L-1 PEG selected somaclone lines were more suited than 50 g L-1 PEG selected somaclone lines under stress as compared with WT. The finding suggests that rice cv PR113 somaclones generated on PEG are found to be drought tolerant under field condition with better yield. 相似文献
184.
Mohammad Wahid Ansari Alok Shukla Ramesh Chandra Pant Narendra Tuteja 《Plant signaling & behavior》2013,8(1)
Malformation is arguably the most crucial disease of mango (Mangifera indica L.) at present. It is receiving great attention not only because of its widespread and destructive nature but also because of its etiology and control is not absolutely understood. Recently, Fusarium mangiferae is found to be associated with mango malformation disease. There are indications that stress ethylene production could be involved in the disease. Here we have shown the first direct evidence of production of ethylene in pure culture of F. mangiferae obtained from mango. The study also revealed that all the isolates dissected from mango acquire morphological features of F. mangiferae showing most similarity to the features of species with accepted standard features. The isolates of F. mangiferae from mango were observed to produce ethylene in significant amounts, ranging from 9.28–13.66 n mol/g dry wt/day. The findings presented here suggest that F. mangiferae could contribute to the malformation of mango by producing ethylene and probably stimulating stress ethylene production in malformed tissue of mango. Ethylene might be produced through 2-oxoglutarate-dependent oxygenase-type ethylene-forming-enzyme (EFE) pathway in Fusarium sp, which needs to be investigated. 相似文献
185.
As an enzyme acting at the junction of gluconeogenic pathway, phosphoenolpyruvate carboxykinase (PEPCK) controls substrate flow from Krebs cycle toward glucose production. Therefore, it would be advantageous to design effective inhibitors to inactivate PEPCK in diabetes mellitus and other abnormalities caused by insulin resistance. Such inhibitors may compensate the metabolic consequences of ex-activity of PEPCK at these conditions. Understanding the mechanism by which inhibitors exert their effect on enzyme activity is of great interest for designing stronger inhibitors. In the present work, molecular dynamic simulations were used to study enzyme-inhibitor interactions. Our results indicate that inhibitors of PEPCK with their short chains interact with enzyme active site through non-covalent interactions of electrostatic and hydrogen bond nature. The data also show that inhibitors neither reach a stable state in their binding site nor make static complex with the enzyme active site. Instead, they interact with functional groups of active site residues in a dynamic fashion. In this way, oxalate and sulfoacetate carrying two negative groups of higher charge density and optimum spacing from each other, show more dynamic behavior (lower stability in their binding site) and more inhibitory effects than other inhibitors used (phosphonoformate, phosphoglycolate and 3-phosphonopropionate). 相似文献
186.
187.
Ghias Uddin Abdul Latif Mohammad Arfan Mumtaz Ali Syed Hamid Hussain Thomas J. Simpson Russel J. Cox Muhammad Iqbal Choudhary 《Phytochemistry letters》2013,6(1):84-89
Three new phenolic compounds, sorlanin (4-(3-(hydroxymethyl)-5-methoxy-7-phenyl-2,3-dihydrobenzo[b][1,4]dioxin-2-yl)-2-methoxyphenol, 1), sorbanin (2-((3,5-dimethoxy-[1,1′-biphenyl]-4-yl)oxy)-1-(4-hydroxy-3-methoxyphenyl)propane-1,3-diol, 2) and sorbalanin (4-(3-(hydroxymethyl)-5,6-dimethoxy-2,3-dihydrobenzo[b][1,4]dioxino[2,3-g]benzofuran-2-yl)-2-methoxyphenol, 3), together with eight known compounds, polystachyol (4), isolariciresinol (5), dihydrodehydrodiconiferyl alcohol (6), tuberculatin (7), ovafolinin E (8), aucuparin (9), 2′-methoxyaucuparin (10), and tetracosyl-3-(3,4-dihydroxyphenyl)acrylate (11), were isolated from Sorbus lanata. The structures of these phytoconstituents were elucidated through extensive spectroscopic techniques, including UV, IR, 1D and 2D NMR, ESI-MS and HRESI-MS experiments. All the compounds except 9 and 10 were isolated for the first time from the genus Sorbus. The isolated compounds were also tested in DPPH radical scavenging reaction where compounds 6, 7, 10 and 11 showed significant activities with IC50 values of 9.2, 11.7, 23.0 and 33.7 μM, respectively. 相似文献
188.
189.
Lisa Kolden Midtb? Mohammad Madani Ibrahim Lene Secher Myrmel Ulrike Liisberg Aune Anita R?yneberg Alvheim Nina S. Liland Bente E. Torstensen Grethe Rosenlund Bj?rn Liaset Trond Brattelid Karsten Kristiansen Lise Madsen 《PloS one》2013,8(1)
Background
To ensure sustainable aquaculture, fish derived raw materials are replaced by vegetable ingredients. Fatty acid composition and contaminant status of farmed Atlantic salmon (Salmo salar L.) are affected by the use of plant ingredients and a spillover effect on consumers is thus expected. Here we aimed to compare the effects of intake of Atlantic salmon fed fish oil (FO) with intake of Atlantic salmon fed a high proportion of vegetable oils (VOs) on development of insulin resistance and obesity in mice.Methodology/principal findings
Atlantic salmon were fed diets where FO was partly (80%) replaced with three different VOs; rapeseed oil (RO), olive oil (OO) or soy bean oil (SO). Fillets from Atlantic salmon were subsequently used to prepare Western diets (WD) for a mouse feeding trial. Partial replacement of FO with VOs reduced the levels of polychlorinated biphenyls (PCB) and dichloro-diphenyl-tricloroethanes (DDT) with more than 50% in salmon fillets, in WDs containing the fillets, and in white adipose tissue from mice consuming the WDs. Replacement with VOs, SO in particular, lowered the n−3 polyunsaturated fatty acid (PUFA) content and increased n−6 PUFA levels in the salmon fillets, in the prepared WDs, and in red blood cells collected from mice consuming the WDs. Replacing FO with VO did not influence obesity development in the mice, but replacement of FO with RO improved glucose tolerance. Compared with WD-FO fed mice, feeding mice WD-SO containing lower PCB and DDT levels but high levels of linoleic acid (LA), exaggerated insulin resistance and increased accumulation of fat in the liver.Conclusion/Significance
Replacement of FO with VOs in aqua feed for farmed salmon had markedly different spillover effects on metabolism in mice. Our results suggest that the content of LA in VOs may be a matter of concern that warrants further investigation. 相似文献190.
Wei Xing Xiaozhou He Mohammad A. Kassir Jie Chen Jiule Ding Jun Sun Jiani Hu Zishu Zhang E. Mark Haacke Yongming Dai 《PloS one》2013,8(2)