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排序方式: 共有466条查询结果,搜索用时 218 毫秒
81.
Vinayak Singh Namita Singh Chauhan Mohit Singh Asif Idris Raju Madanala Veena Pande Chandra Sekhar Mohanty 《Plant signaling & behavior》2014,9(10)
An in vitro method of multiple shoot induction and plant regeneration in Psophocarpus tetragonolobus (L.) DC was developed. Cotyledons, hypocotyls, epicotyls, internodal and young seedling leaves were used as explants. MS media supplemented with various concentrations of either thidiazuron (TDZ) or N6-benzylaminopurine (BAP) along with NAA or IAA combinations were used to determine their influence on multiple shoot induction. MS media supplemented with TDZ induced direct shoot regeneration when epicotyls and internodal segments were used as explants. TDZ at 3 mg L−1 induced highest rate (89.2 ± 3.28%) of regeneration with (13.4 ± 2.04) shoots per explant. MS media supplemented with BAP in combination with NAA or IAA induced callus mediated regeneration when cotyledons and hypocotyls were used as explants. BAP (2.5 mg L−1) and IAA (0.2 mg L−1) induced highest rate (100 ± 2.66%) of regeneration with (23.2 ± 2.66) shoots per explant. Mature plants produced from regenerated shoots were transferred successfully to the greenhouse. In a comparative study, the phenolics contents of various parts of greenhouse-grown plants with that of in vitro-raised plants showed significant variations. 相似文献
82.
Sunil A. Nankar Abhay H. Pande 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2014,1841(4):620-629
Apolipoprotein-derived peptides are promising candidates for the treatment of various inflammatory conditions. The beneficial effects of these peptides are based on multiple mechanisms; prominent among them being high-affinity binding to pro-inflammatory oxidized phospholipids (Ox-PLs) and facilitating their sequestration/metabolism/clearance in the body. This indicates that peptides which can bind exclusively to Ox-PLs without recognizing normal, non-oxidized phospholipids (non-Ox-PLs) will be more potent anti-inflammatory agent than that of the peptides that bind to both Ox-PLs and non-Ox-PLs. In order to develop such Ox-PL-specific peptides, the knowledge about the properties (molecular determinants) of peptides that govern their Ox-PL preference is a must. In this study we have synthesized eleven peptides corresponding to the conserved regions of human apolipoprotein E and compared their biochemical properties, lipid-binding specificities, and anti-inflammatory properties. Our results show that these peptides exhibit considerably different specificities towards non-Ox-PL and different species of Ox-PLs. Some of these peptides bind exclusively to the Ox-PLs and inhibit the pro-inflammatory function of Ox-PLs in human blood. Biochemical characterization revealed that the peptides possess substantially different properties. Our results suggest that physicochemical properties of peptides play an important role in their lipid-binding specificity. 相似文献
83.
Vani Pande Nivedita Mitra Saket Rahul Bagde Ramanujam Srinivasan Pananghat Gayathri 《The Journal of cell biology》2022,221(5)
MreB, the bacterial ancestor of eukaryotic actin, is responsible for shape in most rod-shaped bacteria. Despite belonging to the actin family, the relevance of nucleotide-driven polymerization dynamics for MreB function is unclear. Here, we provide insights into the effect of nucleotide state on membrane binding of Spiroplasma citri MreB5 (ScMreB5). Filaments of ScMreB5WT and an ATPase-deficient mutant, ScMreB5E134A, assemble independently of the nucleotide state. However, capture of the filament dynamics revealed that efficient filament formation and organization through lateral interactions are affected in ScMreB5E134A. Hence, the catalytic glutamate functions as a switch, (a) by sensing the ATP-bound state for filament assembly and (b) by assisting hydrolysis, thereby potentially triggering disassembly, as observed in other actins. Glu134 mutation and the bound nucleotide exhibit an allosteric effect on membrane binding, as observed from the differential liposome binding. We suggest that the conserved ATP-dependent polymerization and disassembly upon ATP hydrolysis among actins has been repurposed in MreBs for modulating filament organization on the membrane. 相似文献
84.
Kumar CP Pande G Shanmugam G 《Apoptosis : an international journal on programmed cell death》1998,3(6):413-419
Cleistanthin B is a potential anticancer agent isolated from the tropical plant Cleistanthus collinus. We have previously shown that cleistanthin B is clastogenic and induces micronuclei formation and chromosomal aberrations. We now show that this compound inhibits DNA synthesis in Chinese hamster ovary (CHO) cells and induces apoptosis in cervical carcinoma (SiHa) cells. Flow cytometric analysis of cleistanthin treated CHO cells revealed that they were blocked in G1. Cervical carcinoma (SiHa) cells exposed to cleistanthin B shrank, rounded up and had condensed chromatin and fragmented nuclei. DNA isolated from cleistanthin treated cells exhibited the characteristic apoptotic ladder when electrophoresed in agarose gels. These results were confirmed by flow cytometry. Etoposide, a structurally similar compound also induced apoptosis in these cells although with a difference. Etoposide induced apoptosis after permitting cells to enter into S phase, while cleistanthin B stopped entry of cells into S phase and subsequently drove them to apoptosis. 相似文献
85.
Derek Mendez Thomas J. Lane Jongmin Sung Jonas Sellberg Clément Levard Herschel Watkins Aina E. Cohen Michael Soltis Shirley Sutton James Spudich Vijay Pande Daniel Ratner Sebastian Doniach 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2014,369(1647)
Tools to study disordered systems with local structural order, such as proteins in solution, remain limited. Such understanding is essential for e.g. rational drug design. Correlated X-ray scattering (CXS) has recently attracted new interest as a way to leverage next-generation light sources to study such disordered matter. The CXS experiment measures angular correlations of the intensity caused by the scattering of X-rays from an ensemble of identical particles, with disordered orientation and position. Averaging over 15 496 snapshot images obtained by exposing a sample of silver nanoparticles in solution to a micro-focused synchrotron radiation beam, we report on experimental efforts to obtain CXS signal from an ensemble in three dimensions. A correlation function was measured at wide angles corresponding to atomic resolution that matches theoretical predictions. These preliminary results suggest that other CXS experiments on disordered ensembles—such as proteins in solution—may be feasible in the future. 相似文献
86.
Solubilization and reconstitution of rat liver mitochondrial carnitine acylcarnitine translocase 总被引:5,自引:0,他引:5
Carnitine acylcarnitine translocase has been solubilized from inverted inner membrane vesicles of rat liver mitochondria with octyl glucoside and reconstituted into asolectin liposomes. For both processes, optimization of the detergent to phospholipid ratio was found crucial for obtaining reconstitutively active liposomes. Reassembly of the solubilized carrier into asolectin liposomes was achieved either by the octyl glucoside dilution method or by Extracti-Gel D column chromatography. The reconstituted system catalyzed exchange diffusion of carnitine, exhibited the expected inhibitor and temperature sensitivity, and discriminated between stereoisomers of octanoylcarnitine. The activity of unidirectional import of carnitine was low compared to exchange diffusion. It showed high-temperature sensitivity and a loss of activity on prolonged sonication that was regained by an appropriate freeze-thaw step subsequently. 相似文献
87.
David C. McGowan Florence Herschke Mourad D. Khamlichi Mari Luz Rosauro Sara M. Pérez Benedicto Frederik Pauwels Bart Stoops Vineet Pande Annick Scholliers Bertrand Van Schoubroeck Wendy Mostmans Kris Van Dijck Tine Thoné Helen Horton Gregory Fanning Tim H.M. Jonckers Pierre Raboisson 《Bioorganic & medicinal chemistry letters》2018,28(19):3216-3221
In a continuing effort to discover novel TLR agonists, herein we report on the discovery and structure–activity relationship of novel tetrahydropyridopyrimidine TLR 7/8 agonists. Optimization of this series towards dual agonist activity and a high clearance profile resulted in the identification of compound 52a1. Evaluation in vivo revealed an interferon stimulated response (ISG) in mice with limited systemic exposure and demonstrated the potential in antiviral treatment or as a vaccine adjuvant. 相似文献
88.
M. Azhar P. S. Manogaran P. K. Kennady G. Pande Vidyanand Nanjundiah 《Experimental cell research》1996,227(2):344
When freshly starved amoebae ofDictyostelium discoideumare loaded with the Ca2+-specific dye indo-1/AM and analyzed in a fluorescence-activated cell sorter, they exhibit a quasi-bimodal distribution of fluorescence. This permits a separation of the population into two classes: H, or “high Ca2+-indo-1 fluorescence,” and L, or “low Ca2+-indo-1 fluorescence.” Simultaneous monitoring of Ca2+-indo-1 and Ca2+-chlortetracycline fluorescence shows that by and large the same cells tend to have high (or low) levels of both cytoplasmic and sequestered Ca2+. Next we label H cells with tetramethylrhodamine isothiocyanate (TRITC) and mix them in a 1:4 ratio with L cells. In the slugs that result, TRITC fluorescence is confined mainly to the anterior prestalk region. This implies that amoebae with relatively high Ca2+at the vegetative stage tend to develop into prestalk cells and those with low Ca2+into prespores.Polysphondylium violaceum,a cellular slime mold that does not possess prestalk and prespore cells, also does not display a Ca2+-dependent heterogeneity at the vegetative stage or in slugs. Finally, confirming earlier findings with the fluorophore fura-2 (Azharet al., Curr. Sci.68, 337–342 (1995)), a prestalk–prespore difference in cellular Ca2+is present in the cells of the slugin vivo.These findings are discussed in light of the possible roles of Ca2+for cell differentiation inD. discoideum. 相似文献
89.
Ayyagari MS Pande R Kamtekar S Marx KA Tripathy SK Gao H Kumar J Akkara JA Kaplan DL 《Biotechnology and bioengineering》1995,45(2):116-121
A molecular assembly in which a conjugated polymer is interfaced with a photodynamic protein is described. The conjugated polymer, functionalized with biotion, is designed such that it can be physisorbed on or chemically grown off a glass surface. The streptavidin-derivatized protein is immobilized on the biotinylated polymer matrix through the strong biotin-streptavidin interactions. The assembly, built on the surface of an optical fiber or on the inside walls of a glass capillary, forms an integral part of a biosensor for the detection of environmental pollutants such as organophosphorus-based insecticides. The Protein in the system can be replaced by any biological macromolecule of interest. We study one specific case, the enzyme alkaline phosphatase. The enzyme catalyzes a reaction producing an intermediate compound that chemiluminesces, and the chemiluminescence singnal is monitored to detect and quantify insecticides such as paraoxon and methyl parathion. Preliminary results indicate ppb level detection with response time less than 1 minute. (c) 1995 John Wiley & Sons, Inc. 相似文献
90.
A recently silenced, duplicate PgiC locus in Clarkia 总被引:1,自引:0,他引:1
Previous electrophoretic analysis showed that 17 diploid species of the
wildflower Clarkia (Onagraceae) have two cytosolic isozymes of
phosphoglucose isomerase (PGIC; EC 5.3.1.9), whereas 15 other diploid
species have a single PGIC. Molecular studies revealed that the two
isozymes in the former species are encoded by duplicate genes, PgiC1 and
PgiC2, whereas the single isozyme in the latter is always encoded by PgiC1.
Phylogenetic analysis of the nucleotide sequences implied that PgiC2 was
silenced four times independently in the genus. Here we describe a psi
PgiC2 from C. mildrediae, a species in which only PgiC1 is expressed. The
discovery of the psi PgiC2 is significant because it confirms a formal
prediction of the phylogenetic analysis. The psi PgiC2 includes 5,039
nucleotides corresponding to 18 of the 23 exons of PgiC, as well as the
intervening introns and 3' nontranslated region. The absence of an increase
of nucleotide substitutions in its "exons" suggests that the gene was
silenced recently. The present study appears to be the first to establish
that a specific duplicate gene locus regularly expressed in a group of
related plant species has been silenced in one of them. The multiple
independent silencings of PgiC2 suggest that it remained functional but
inessential in ancestral lineages. We discuss the possibility that PgiC2
may have been preserved in these lineages by selection against mutants
causing defective PGIC1- PGIC2 heterodimers.
相似文献