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1.
A survey of cultivated heirloom tomato varieties identifies four new mutant alleles at the green-flesh locus 总被引:1,自引:0,他引:1
Cornelius S. Barry Priyanka Pandey 《Molecular breeding : new strategies in plant improvement》2009,24(3):269-276
The process of crop domestication occurs through the selection and subsequent propagation of novel alleles that improve traits
of interest. Cultivated tomato (Solanum lycopersicum), particularly heirloom varieties, exhibit a wide range of variation in fruit size, shape and color. The green-flesh mutant of tomato possesses a stay-green phenotype resulting in fruits that ripen to a red-brown color, due to the retention
of chlorophyll and the simultaneous accumulation of lycopene. The recent identification of the GREEN-FLESH gene provides a molecular tool with which to investigate the origin of a subset of cultivated tomato varieties that resemble
the green-flesh mutant. Sequence analysis of the GF locus from 26 varieties revealed the existence of four previously unidentified null alleles. This study illustrates the potential
of cultivated tomato varieties, including heritage cultivars, heirlooms, and land races, for uncovering new alleles in genes
of interest. 相似文献
2.
Rashi Verma Monika Yadav Rajabrata Bhuyan Shweta Aggarwal Arnab Nayek 《Journal of receptor and signal transduction research》2016,36(6):601-616
Computer-aided antibody engineering has been successful in the design of new biologics for disease diagnosis and therapeutic interventions. Interleukin-6 (IL-6), a well-recognized drug target for various autoimmune and inflammatory diseases such as rheumatoid arthritis, multiple sclerosis, and psoriasis, was investigated in silico to design potential lead antibodies. Here, crystal structure of IL-6 along with monoclonal antibody olokizumab was explored to predict antigen–antibody (Ag???Ab)-interacting residues using DiscoTope, Paratome, and PyMOL. Tyr56, Tyr103 in heavy chain and Gly30, Ile31 in light chain of olokizumab were mutated with residues Ser, Thr, Tyr, Trp, and Phe. A set of 899 mutant macromolecules were designed, and binding affinity of these macromolecules to IL-6 was evaluated through Ag???Ab docking (ZDOCK, ClusPro, and Rosetta server), binding free-energy calculations using Molecular Mechanics/Poisson Boltzman Surface Area (MM/PBSA) method, and interaction energy estimation. In comparison to olokizumab, eight newly designed theoretical antibodies demonstrated better result in all assessments. Therefore, these newly designed macromolecules were proposed as potential lead antibodies to serve as a therapeutics option for IL-6-mediated diseases. 相似文献
3.
Interferons are known to potentiate various biological effects of tumor necrosis factor (TNF). Recently, two different types of TNF receptors with molecular masses of 60 kDa (p60) and 80 kDa (p80), primarily expressed by epithelial cells and myeloid cells, respectively, have been identified. In the present report, we examined the effect of interferon-gamma (IFN-gamma) on each type of TNF receptor. Our results indicate that IFN-gamma induces TNF receptors on both myeloid (e.g. HL-60) and epithelial cells (e.g. HeLa). Furthermore, by using antibodies specific to each type of receptor, we demonstrate that both TNF receptors are equally inducible by IFN-alpha, IFN-beta and IFN-gamma. Thus, the increase in TNF receptors by interferons may play a role in their synergistic cellular response. 相似文献
4.
Vijay Pal Singh Rangoli Aggarwal Suchita Singh Arpita Banik Tanveer Ahmad Bijay Ranjan Patnaik Giridharan Nappanveettil Kunal Pratap Singh Madan Lal Aggarwal Balaram Ghosh Anurag Agrawal 《PloS one》2015,10(6)
Epidemiological studies have shown an increased obesity-related risk of asthma. In support, obese mice develop airway hyperresponsiveness (AHR). However, it remains unclear whether the increased risk is a consequence of obesity, adipogenic diet, or the metabolic syndrome (MetS). Altered L-arginine and nitric oxide (NO) metabolism is a common feature between asthma and metabolic syndrome that appears independent of body mass. Increased asthma risk resulting from such metabolic changes would have important consequences in global health. Since high-sugar diets can induce MetS, without necessarily causing obesity, studies of their effect on arginine/NO metabolism and airway function could clarify this aspect. We investigated whether normal-weight mice with MetS, due to high-fructose diet, had dysfunctional arginine/NO metabolism and features of asthma. Mice were fed chow-diet, high-fat-diet, or high-fructose-diet for 18 weeks. Only the high-fat-diet group developed obesity or adiposity. Hyperinsulinemia, hyperglycaemia, and hyperlipidaemia were common to both high-fat-diet and high-fructose-diet groups and the high-fructose-diet group additionally developed hypertension. At 18 weeks, airway hyperresponsiveness (AHR) could be seen in obese high-fat-diet mice as well as non-obese high-fructose-diet mice, when compared to standard chow-diet mice. No inflammatory cell infiltrate or goblet cell metaplasia was seen in either high-fat-diet or high-fructose-diet mice. Exhaled NO was reduced in both these groups. This reduction in exhaled NO correlated with reduced arginine bioavailability in lungs. In summary, mice with normal weight but metabolic obesity show reduced arginine bioavailability, reduced NO production, and asthma-like features. Reduced NO related bronchodilation and increased oxo-nitrosative stress may contribute to the pathogenesis. 相似文献
5.
Characterization of recombinant human lymphotoxin (tumor necrosis factor-beta) produced by a mammalian cell line 总被引:1,自引:0,他引:1
Lymphotoxin (LT) was purified from serum-free conditioned media of a recombinant mammalian cell line transfected with human lymphotoxin cDNA. The purification scheme consisted of controlled pore glass chromatography, Q-Sepharose ion-exchange chromatography, and concanavalin A-Sepharose chromatography. The purified protein was found to be homogeneous by reverse-phase high-performance liquid chromatography and had an approximate specific activity of 130 X 10(6) units per milligram protein as determined by the L-929 cytotoxicity assay. Purified LT had an isoelectric point of approximately 6.85 and an apparent molecular weight of 50,000 by gel permeation high-pressure liquid chromatography. However, when analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, two distinct bands at approximate molecular sizes of 25 and 20 kDa were observed. Both the bands were immunoreactive by Western blot analysis and found to be associated with biological activity. The two forms of lymphotoxin differed from each other with respect to protein structure. Amino-terminal amino acid sequence analysis revealed that the 25-kDa LT sequence starts with Leu-Pro-Gly-residues whereas that of the 20-kDa LT begins with His-Leu-Ala; thus the latter form is truncated by 20 amino acid residues from the amino terminal. Two species of LT also differed from each other with respect to carbohydrate structure. Enzymatic removal of sialic acid reduced the molecular weight of 25 kDa by approximately 5 kDa whereas that of the 20-kDa LT was unchanged. A reduction in an apparent molecular size by approximately 4 kDa of both species of LT was observed on removal of N-linked oligosaccharides. Treatment with O-Glycanase had minimal effect on either form of LT. The recombinant lymphotoxin described here was found superior in its solubility behavior as compared to bacterial cell derived LT. Overall, mammalian cell line derived recombinant LT appears closer in its properties to natural LT than does bacterial cell derived recombinant LT. 相似文献
6.
A pro-drug of zidovudine with enhanced efficacy against human immunodeficiency virus 总被引:1,自引:0,他引:1
S R Gogu S K Aggarwal S R Rangan K C Agrawal 《Biochemical and biophysical research communications》1989,160(2):656-661
In an attempt to alleviate the drug-related toxicity of zidovudine in patients with AIDS, a pro-drug of zidovudine, 5'-[(1,4-dihydro-1-methyl-3-pyridinylcarbonyl)oxy]-3'-azido-2',3'- dideoxythymidine (DP-AZT), has been evaluated. Cellular uptake by H9 cells and peripheral blood lymphocytes (PBL) with zidovudine and DP-AZT showed at least a 50% greater intracellular concentration of DP-AZT within 2 hr. DP-AZT was significantly less toxic to murine bone marrow cells as measured by CFU-E assay. The ED50 concentration to inhibit the production of HIV specific p24 antigen was 0.05 microM for DP-AZT whereas zidovudine required 0.125 microM. These results demonstrated that DP-AZT has a higher therapeutic ratio than zidovudine as an anti-HIV-1 agent. 相似文献
7.
8.
P M Peters J R Ortaldo M R Shalaby L P Svedersky G E Nedwin T S Bringman P E Hass B B Aggarwal R B Herberman D V Goeddel 《Journal of immunology (Baltimore, Md. : 1950)》1986,137(8):2592-2598
Highly purified populations of large granular lymphocytes (LGL) have been shown to mediate natural killer (NK) cell activity. The mechanism of target cell killing by NK cells is as yet undefined; however, it has been postulated that such killing may involve soluble cytotoxic factors produced and secreted by NK cells. The data presented show that NK-sensitive, but not NK-resistant, tumor cell lines induce highly purified populations of human LGL to produce factors with cytotoxic and/or cytostatic activities. We have identified one of these factors as tumor necrosis factor-alpha (TNF-alpha), and have shown that production of this factor is enhanced by recombinant human interferon-gamma (rHuIFN-gamma). We have also examined the role of TNF-alpha in the cytotoxic function of NK cells. The data show that although highly purified LGL populations produce low levels of TNF-alpha, the cytotoxic/cytostatic activity of this lymphokine on tumor target cells does not correlate with the cytotoxic activity of highly purified populations of LGL on tumor target cells. Furthermore, NK cell-mediated cytotoxicity is not reliably inhibited by antibodies directed against various epitopes of recombinant human TNF-alpha and/or recombinant TNF-beta (lymphotoxin) or rHuIFN-gamma. These data show that although TNF-alpha is produced by highly purified NK-containing LGL cell populations, this factor does not appear to be responsible for NK cell cytotoxicity against classical NK target cells such as Molt-4 or K562. We suggest that NK function can be attributed to a combination of factors rather than to a single factor alone, and that at least two major phenomena are involved in LGL function: the rapid cytotoxic events which lead to the cell lysis measured in classical in vitro NK assays such as against K562; and the release of factors such as TNF-alpha with cytotoxic/cytostatic activities which would inhibit the growth of invading tumor cells in vivo. 相似文献
9.
Cytotoxicity of mononuclear leukocytes (MNL) to Giardia lamblia was compared by using two techniques. The first method assessed the viability of surviving Giardia directly by culturing and the second method measured release of incorporated [3H] thymidine. Cytotoxicity, as measured directly by culturing and visual assessment, showed that the numbers of surviving Giardia decreased over time whether cultured with or without MNL but that Giardia survived significantly better in the presence of MNL at 18 hr (21.8 +/- 8.3% with MNL compared with 3.4 +/- 1.5% without MNL). Release of [3H]thymidine increased whether Giardia were cultured with or without MNL and although there was a tendency for increased release with MNL, there was no significant difference. Dead labeled Giardia released significantly more label in the presence of MNL than without MNL, suggesting that MNL cause release of [3H]thymidine after phagocytosis. The thymidine release assay therefore does not measure spontaneous cytotoxicity of MNL to Giardia. 相似文献
10.
Summary Six carbamate pesticides namely 1-naphthol, sevin, dimetilan, trematan, NaDDC and dymid were studied to see their effect on
nodulation and nitrogen fixation inPisum sativum andVigna sinensis. Low concentrations of the pesticides have little effect on nodulation and nitrogen fixation, whereas higher concentrations
adversely effect these processes. The results also indicate that then sensitivity depends upon the species of the Rhizobium
and also the type of the pesticide. Pesticides belonging to the carbamate group differ in their capacity to affect nodulation
and nitroge fixation. 相似文献