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81.
Chavda S Liu Y Babu B Davis R Sielaff A Ruprich J Westrate L Tronrud C Ferguson A Franks A Tzou S Adkins C Rice T Mackay H Kluza J Tahir SA Lin S Kiakos K Bruce CD Wilson WD Hartley JA Lee M 《Biochemistry》2011,50(15):3127-3136
With the aim of incorporating a recognition element that acts as a fluorescent probe upon binding to DNA, three novel pyrrole (P) and imidazole (I)-containing polyamides were synthesized. The compounds contain a p-anisylbenzimidazolecarboxamido (Hx) moiety attached to a PP, IP, or PI unit, giving compounds HxPP (2), HxIP (3), and HxPI (4), respectively. These fluorescent hybrids were tested against their complementary nonfluorescent, non-formamido tetraamide counterparts, namely, PPPP (5), PPIP (6), and PPPI (7) (cognate sequences 5'-AAATTT-3', 5'-ATCGAT-3', and 5'-ACATGT-3', respectively). The binding affinities for both series of polyamides for their cognate and noncognate sequences were ascertained by surface plasmon resonance (SPR) studies, which revealed that the Hx-containing polyamides gave binding constants in the 10(6) M(-1) range while little binding was observed for the noncognates. The binding data were further compared to the corresponding and previously reported formamido-triamides f-PPP (8), f-PIP (9), and f-PPI (10). DNase I footprinting studies provided additional evidence that the Hx moiety behaved similarly to two consecutive pyrroles (PP found in 5-7), which also behaved like a formamido-pyrrole (f-P) unit found in distamycin and many formamido-triamides, including 8-10. The biophysical characterization of polyamides 2-7 on their binding to the abovementioned DNA sequences was determined using thermal melts (ΔT(M)), circular dichroism (CD), and isothermal titration calorimetry (ITC) studies. Density functional calculations (B3LYP) provided a theoretical framework that explains the similarity between PP and Hx on the basis of molecular electrostatic surfaces and dipole moments. Furthermore, emission studies on polyamides 2 and 3 showed that upon excitation at 322 nm binding to their respective cognate sequences resulted in an increase in fluorescence at 370 nm. These low molecular weight polyamides show promise for use as probes for monitoring DNA recognition processes in cells. 相似文献
82.
Different strategies of petal senescence and some important events associated with it have been discussed. On the basis of
sensitivity to ethylene and associated symptoms of senescence, petal senescence has been classified into five different classes;
besides changes in membrane permeability, autophagy and involvement of VPEs (Vacuolar processing enzymes), degradation of
nucleic acids, protein turn over and remobilization of essential nutrients during petal senescence have been discussed. Nucleus
appears to play a central role in administrating the execution of the events associated with petal senescence. Protein turn
over appears to be an important factor governing petal senescence in both ethylene-sensitive and ethylene-insensitive flower
systems and that the loss of membrane integrity, vacuolar autophagy and remobilization of essential nutrients being its important
consequences. Autophagy seems to be a main process responsible for cell dismantling and remobilization of macromolecules besides
final disintegration of nucleus. A large number of senescence-associated genes have been found to be differentially expressed
during petal senescence. On the basis of the available literature, a schematic model representing some important events associated
with petal senescence has been constructed. The review recommends that more elaborate work is required at cellular and organelle
level to understand the ethylene-independent pathway and its execution in both ethylene-sensitive and ethylene-insensitive
flower systems. It also recommends that ethylene sensitivity should not be generally assigned to plants at the family level
on the basis of response of a few species in a family. 相似文献
83.
Zuber M Zia KM Tabassum S Jamil T Barkaat-Ul-Hasin S Khosa MK 《International journal of biological macromolecules》2011,49(1):1-6
The preparation of amino silicone based softeners with different emulsifiers was carried out and adsorbed onto the surfaces of cotton and blends of cotton/polyester fabrics. The softened fabrics have high surface area, so poorly performance in washing and rubbing fastness. It is obvious from the results of colorfastness to rubbing and washing that some of the samples of the dyed fabric treated with prepared softeners have shown some poor rating as compared to the untreated fabrics. However the other two samples have shown acceptable rubbing fastness results without losing softness and permanent handle. It can be observed that washing of the printed treated fabric remains unaffected almost in all the studied samples. Moreover, the application of the prepared softeners has imparted anti pilling property to the fabric. It can be seen that there is a remarkable increase in weights of treated fabrics as compared to the untreated fabrics. 相似文献
84.
Kenyon JC Tanner SJ Legiewicz M Phillip PS Rizvi TA Le Grice SF Lever AM 《Nucleic acids research》2011,39(15):6692-6704
Feline immunodeficiency virus (FIV) infects many species of cat, and is related to HIV, causing a similar pathology. High-throughput selective 2' hydroxyl acylation analysed by primer extension (SHAPE), a technique that allows structural interrogation at each nucleotide, was used to map the secondary structure of the FIV packaging signal RNA. Previous studies of this RNA showed four conserved stem-loops, extensive long-range interactions (LRIs) and a small, palindromic stem-loop (SL5) within the gag open reading frame (ORF) that may act as a dimerization initiation site (DIS), enabling the virus to package two copies of its genome. Our analyses of wild-type (wt) and mutant RNAs suggest that although the four conserved stem-loops are static structures, the 5' and 3' regions previously shown to form LRI also adopt an alternative, yet similarly conserved conformation, in which the putative DIS is occluded, and which may thus favour translational and splicing functions over encapsidation. SHAPE and in vitro dimerization assays were used to examine SL5 mutants. Dimerization contacts appear to be made between palindromic loop sequences in SL5. As this stem-loop is located within the gag ORF, recognition of a dimeric RNA provides a possible mechanism for the specific packaging of genomic over spliced viral RNAs. 相似文献
85.
Sabuhi R Ali Q Asghar M Al-Zamily NR Hussain T 《American journal of physiology. Renal physiology》2011,300(3):F700-F706
Inflammation and oxidative stress are believed to contribute to hypertension in obesity/diabetes. Recently, we reported a role for the AT(2) receptor in blood pressure control in obese Zucker rats. However, the role of AT(2) receptors in inflammation and oxidative stress in obesity is not known. Therefore, in the present study, we tested the effects of the AT(2) receptor agonist CGP-42112A on inflammation and oxidative stress in obese Zucker rats and compared them in their lean counterparts. Rats were systemically treated with either vehicle (control) or CGP-42112A (1 μg·kg(-1)·min(-1); osmotic pump) for 2 wk. Markers of inflammation (CRP, MCP-1, TNF-α, and IL-6) and oxidative stress (HO-1, gp-91(phox)) as well as an antioxidant (SOD) were determined. Control obese rats had higher plasma levels of CRP, MCP-1, TNF-α, IL-6, and HO-1 compared with control lean rats. Conversely, plasma SOD activity was lower in control obese than in control lean rats. Furthermore, the protein levels of TNF-α and gp-91(phox) were higher in the kidney cortex of control obese rats. Interestingly, CGP-42112A treatment in obese rats reduced the plasma and kidney cortex inflammatory (TNF-α, IL-6) and oxidative stress (gp-91(phox)) markers and increased plasma SOD activity to the levels seen in lean control rats. However, CGP-42112A treatment in lean rats increased inflammatory (TNF-α, IL-6) and oxidative stress (gp-91(phox)) markers in the plasma and kidney cortex. Our present studies suggest anti-inflammatory and antioxidative functions of AT(2) receptor in obese Zucker rats but proinflammatory and prooxidative functions in lean Zucker rats. 相似文献
86.
87.
Sauder CJ Zhang CX Ngo L Werner K Lemon K Duprex WP Malik T Carbone K Rubin SA 《Journal of virology》2011,85(14):7059-7069
Mumps virus (MuV) is highly neurotropic and was the leading cause of aseptic meningitis in the Western Hemisphere prior to widespread use of live attenuated MuV vaccines. Due to the absence of markers of virus neuroattenuation and neurovirulence, ensuring mumps vaccine safety has proven problematic, as demonstrated by the occurrence of aseptic meningitis in recipients of certain vaccine strains. Here we examined the genetic basis of MuV neuroattenuation and neurovirulence by generating a series of recombinant viruses consisting of combinations of genes derived from a cDNA clone of the neurovirulent wild-type 88-1961 strain (r88) and from a cDNA clone of the highly attenuated Jeryl Lynn vaccine strain (rJL). Testing of these viruses in rats demonstrated the ability of several individual rJL genes and gene combinations to significantly neuroattenuate r88, with the greatest effect imparted by the rJL nucleoprotein/matrix protein combination. Interestingly, no tested combination of r88 genes, including the nucleoprotein/matrix protein combination, was able to convert rJL into a highly neurovirulent virus, highlighting mechanistic differences between processes involved in neuroattenuation and neurovirulence. 相似文献
88.
Muhammad Muzammal Adeel Muhammad Qasim Usman Ali Ashfaq Muhammad Shareef Masoud Mahmood ur Rehman Muhammad Tahir ul Qamar Muhammad Rizwan Javed 《Bioinformation》2014,10(7):454-459
Computational tools occupy the prime position in the analysis of large volume of post-genomic data. These tools have advantage
over the wet lab experiments in terms of high coverage, cost and time. Breast cancer is the most common cancer in females
worldwide. It is a genetically heterogeneous disorder and many genes are involved in the pathway of the disease. Mutations in
metastasis suppressor gene are the major cause of the disease. In this study, the effects of mutations in breast cancer metastasis
suppressor 1gene upon protein structure and function were examined by means of computational tools and information from
databases.This study can be useful to predict the potential effect of every allelic variant, devise new biological experiments and to
interpret and predict the patho-physiological impact of new mutations or non-synonymous polymorphisms. 相似文献
89.
Waheed Arshad Ihsan-ul- Haq Mohammad Tahir Waheed Kirankumar S. Mysore Bushra Mirza 《PloS one》2014,9(5)
Tomato (Solanum lycopersicum L.) is the second most important cultivated crop next to potato, worldwide. Tomato serves as an important source of antioxidants in human diet. Alternaria solani and Fusarium oxysporum cause early blight and vascular wilt of tomato, respectively, resulting in severe crop losses. The foremost objective of the present study was to generate transgenic tomato plants with rolB gene and evaluate its effect on plant morphology, nutritional contents, yield and resistance against fungal infection. Tomato cv. Rio Grande was transformed via Agrobacterium tumefaciens harbouring rolB gene of Agrobacterium rhizogenes. rolB. Biochemical analyses showed considerable improvement in nutritional quality of transgenic tomato fruits as indicated by 62% increase in lycopene content, 225% in ascorbic acid content, 58% in total phenolics and 26% in free radical scavenging activity. Furthermore, rolB gene significantly improved the defence response of leaves of transgenic plants against two pathogenic fungal strains A. solani and F. oxysporum. Contrarily, transformed plants exhibited altered morphology and reduced fruit yield. In conclusion, rolB gene from A. rhizogenes can be used to generate transgenic tomato with increased nutritional contents of fruits as well as improved foliar tolerance against fungal pathogens. 相似文献
90.
Z. U. Zia H. A. Sadaqat M. H. N. Tahir B. Sadia B. S. Bushman D. Hole L. Michaels W. Malik 《Russian Journal of Genetics》2014,50(5):498-507
Microsatellites or simple sequence repeats (SSRs) were used for the estimation of genetic diversity among a group of 40 sunflower lines developed at the research area of Department of Plant Breeding and Genetics, University of Agriculture, Faisalabad. Total numbers of alleles amplified by 22 polymorphic primers were 135 with an average of 6.13 alleles per locus, suggesting that SSR is a powerful technique for assessment of genetic diversity at molecular level. The expected heterozygosity (PIC) ranged from 0.17 to 0.89. The highest PIC value was observed at the locus C1779. The genetic distances ranged from 9% to 37%. The highest genetic distance was observed between the lines L50 and V3. Genetic distances were low showing lesser amount of genetic diversity among the sunflower lines. 相似文献