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1.
Ahmad Bilal Khan M. Masroor A. Jaleel Hassan Shabbir Asfia Sadiq Yawar Uddin Moin 《Journal of Plant Growth Regulation》2020,39(1):346-357
Journal of Plant Growth Regulation - Interest in the use of the nanoparticles as plant growth elicitors mushroomed within the last decade and the field is quite intriguing to meet the growing needs... 相似文献
2.
Faisal?Thayyullathil Siraj?Pallichankandy Anees?Rahman Jaleel?Kizhakkayil Shahanas?Chathoth Mahendra?Patel Sehamuddin?GaladariEmail author 《Journal of molecular signaling》2013,8(1):2
Background
Prostate apoptosis response-4 (Par-4) is a tumor-suppressor protein that selectively activates and induces apoptosis in cancer cells, but not in normal cells. The cancer specific pro-apoptotic function of Par-4 is encoded in its centrally located SAC (Selective for Apoptosis induction in Cancer cells) domain (amino acids 137–195). The SAC domain itself is capable of nuclear entry, caspase activation, inhibition of NF-κB activity, and induction of apoptosis in cancer cells. However, the precise mechanism(s) of how the SAC domain is released from Par-4, in response to apoptotic stimulation, is not well explored.Results
In this study, we demonstrate for the first time that sphingosine (SPH), a member of the sphingolipid family, induces caspase-dependant cleavage of Par-4, leading to the release of SAC domain containing fragment from it. Par-4 is cleaved at the EEPD131G site on incubation with caspase-3 in vitro, and by treating cells with several anti-cancer agents. The caspase-3 mediated cleavage of Par-4 is blocked by addition of the pan-caspase inhibitor z-VAD-fmk, caspase-3 specific inhibitor Ac-DEVD-CHO, and by introduction of alanine substitution for D131 residue. Moreover, suppression of SPH-induced Akt dephosphorylation also abrogated the caspase dependant cleavage of Par-4.Conclusion
Evidence provided here shows that Par-4 is cleaved by caspase-3 during SPH-induced apoptosis. Cleavage of Par-4 leads to the generation of SAC domain containing fragment which may possibly be essential and sufficient to induce or augment apoptosis in cancer cells.3.
There has been considerable recent progress in understanding the processes involved in brain development. An analysis of a number of neurological conditions, together with our studies of the hydrocephalic Texas (H-Tx) rat, presents an important role for cerebrospinal fluid (CSF) in the developmental process. The fluid flow is essentially one-way and the location of the choroid plexuses in the lateral, third, and fourth ventricles allows for the possibility of new components being added to the fluid at these points. The role of the fourth ventricular CSF is particularly interesting since this is added to the fluid downstream of the cerebral hemisphere germinal epithelium (the main site of cortical cell proliferation and differentiation) and is destined for the basal cisterns and subarachnoid space suggesting different target cells to those within the ventricular system. Moreover, other sources of additions to the CSF exist, notably the subcommissural organ, which sits at the opening of the third ventricle into the cerebral aqueduct and is the source of Reisner's fibre, glycoproteins, and unknown soluble proteins. In this paper a model for the role of CSF is developed from studies of the development of the cortex of the H-Tx rat. We propose that CSF is vital in controlling development of the nervous system along the whole length of the neural tube and that the externalisation of CSF during development is essential for the formation of the layers of neurones in the cerebral cortex. 相似文献
4.
Salt stress-induced changes in antioxidant enzymes, lipid peroxidation, proline and glycine betaine contents, and proline-metabolizing
enzymes were examined in the leaves of two mulberry cultivars (Local and Sujanpuri). With increasing salinity up to 150 mM
NaCl, superoxide dismutase, catalase, ascor-bate peroxidase, guaiacol peroxidase, glutathione reductase, and monodehydroascorbate
reductase activities were increased in both cultivars as compared to control, but more pronounced increase was observed in
cv. Local. Salt stress enhanced the rate of lipid peroxidation (as indicated by increasing MDA content) in both cultivars.
Under NaCl stress, cv. Local showed less change in the MDA content than cv. Sujanpuri. Salt stress resulted in a significant
accumulation of free proline in mulberry leaves, and more accumulation was detected in cv. Local than cv. Sujanpuri. The leaves
of cv. Local showed 9-fold accumulation of glycine betaine in comparision with cv. Sujanpuri after 20 days at 150 mM NaCl.
A decrease in proline oxidase activity and an increase in γ-glutamyl kinase activity were observed with increasing NaClconcentration.
The relative water content and electrolyte leakage also decreased after increasing the NaCl concentration, but a decrease
was more pronounced in cv. Sujanpuri than in cv. Local. The results indicate that oxidative stress may play an important role
in salt-stressed mulberry plants and cv. Local have more efficient antioxidant characteristics, which could provide for a
better protection against oxidative stress. 相似文献
5.
Black pepper is an important medicinal spice traded internationally. The extraction of high quality genomic DNA for PCR amplification
from dried black pepper is challenging because of the presence of the exceptionally large amount of oxidized polyphenolic
compounds, polysaccharides and other secondary metabolites. Here we report a modified hexadecyl trimethyl ammonium bromide
(CTAB) protocol by incorporating potassium acetate and a final PEG precipitation step to isolate PCR amplifiable genomic DNA
from dried and powdered berries of black pepper. The protocol has trade implication as it will help in the PCR characterization
of traded black peppers from different countries. 相似文献
6.
The role of the kinase homology domain (KHD) in receptor guanylyl cyclases is to regulate the activity of the catalytic guanylyl cyclase domain. The KHD lacks many of the amino acids required for phosphotransfer activity and, therefore, is not expected to possess kinase activity. Guanylyl cyclase activity of the receptor guanylyl cyclase C (GC-C) is modulated by ATP, and computational modeling showed that the KHD can adopt a structure similar to protein kinases, suggesting that the KHD is the site for ATP interaction. A monoclonal antibody, GCC:4D7, raised to the KHD of GC-C, fails to react with GC-C in the presence of ATP and ATP analogues that regulate GC-C catalytic activity, indicating that a conformational change occurs in the KHD on ATP binding. Mapping of the epitope of the antibody through the use of recombinant protein constructs and phage display showed that the epitope for GC-C:4D7 lies immediately C-terminal to a critical lysine residue (Lys516 in GC-C), required for ATP interaction in protein kinases. By employing a novel approach utilizing ATP-agarose affinity chromatography, we demonstrate that the intracellular domain of GC-C and the KHD bind ATP. Mutation of Lys516 to Ala abolishes ATP binding. Thus, this report is the first to show direct ATP binding to the pseudokinase domain of receptor guanylyl cyclase C, as well as to identify dramatic conformational changes that occur in this domain on ATP binding, akin to those seen in catalytically active protein kinases. 相似文献
7.
Kizhakkayil J Thayyullathil F Chathoth S Hago A Patel M Galadari S 《Free radical biology & medicine》2012,52(9):1854-1864
Depletion of intracellular glutathione (GSH) is the prime hallmark of the progression of apoptosis. Previously, we reported that curcumin induces reactive oxygen species (ROS)-mediated depletion of GSH, which leads to caspase-dependent and independent apoptosis in mouse fibroblast cells (F. Thayyullathil et al., Free Radic. Biol. Med.45, 1403-1412, 2008). In this study, we investigated the antileukemic potential of curcumin in vitro, and we further examined the molecular mechanisms of curcumin-induced apoptosis in human leukemic cells. Curcumin suppresses the growth of human leukemic cells via ROS-independent GSH depletion, which leads to caspase activation, inhibition of sphingomyelin synthase (SMS) activity, and induction of ceramide (Cer) generation. Pretreatment of leukemic cells with carbobenzoxy-Val-Ala-Asp fluoromethylketone, a universal inhibitor of caspases, abrogates the SMS inhibition and Cer generation, and in turn prevents curcumin-induced cell death. Curcumin treatment of leukemic cells also downregulates the expression of the inhibitor of apoptosis proteins (IAPs), phospho-Akt, c-Myc, and cyclin D1. Extracellular supplementation with GSH attenuates curcumin-induced depletion of GSH, caspase-dependent inhibition of SMS, Cer generation, and downregulation of IAPs, whereas, L-D-buthionine sulfoximine, a widely used inhibitor of GSH synthesis, potentiates GSH depletion, Cer generation, and apoptosis induced by curcumin. Taken together, our findings provide evidence suggesting for the first time that GSH regulates caspase-dependent inhibition of SMS activity, Cer generation, and apoptosis induced by curcumin in human leukemic cells. 相似文献
8.
U Bashir Aamir N Badar MR Mehmood N Nisar RM Suleman S Shaukat S Sharif J Kamran SS Zaidi BM Kazi L Gubareva X Xu R Garten A Klimov 《PloS one》2012,7(8):e41866
Background
In early 2009, a novel influenza A(H1N1) virus that emerged in Mexico and United States rapidly disseminated worldwide. The spread of this virus caused considerable morbidity with over 18000 recorded deaths. The new virus was found to be a reassortant containing gene segments from human, avian and swine influenza viruses.Methods/Results
The first case of human infection with A(H1N1)pdm09 in Pakistan was detected on 18th June 2009. Since then, 262 laboratory-confirmed cases have been detected during various outbreaks with 29 deaths (as of 31st August 2010). The peak of the epidemic was observed in December with over 51% of total respiratory cases positive for influenza. Representative isolates from Pakistan viruses were sequenced and analyzed antigenically. Sequence analysis of genes coding for surface glycoproteins HA and NA showed high degree of high levels of sequence identity with corresponding genes of regional viruses circulating South East Asia. All tested viruses were sensitive to Oseltamivir in the Neuraminidase Inhibition assays.Conclusions
Influenza A(H1N1)pdm09 viruses from Pakistan form a homogenous group of viruses. Their HA genes belong to clade 7 and show antigenic profile similar to the vaccine strain A/California/07/2009. These isolates do not show any amino acid changes indicative of high pathogenicity and virulence. It is imperative to continue monitoring of these viruses for identification of potential variants of high virulence or drug resistance. 相似文献9.
Photosynthesis and photosystem 2 efficiency of two salt-adapted halophytic seashore <Emphasis Type="Italic">Cakile maritima</Emphasis> ecotypes 总被引:1,自引:1,他引:0
W. Megdiche K. Hessini F. Gharbi C. A. Jaleel R. Ksouri C. Abdelly 《Photosynthetica》2008,46(3):410-419
The effects of salinity (0–400 mM NaCl, marked S0, S100, S200, and S400) on growth, photosynthesis, photosystem 2 (PS2) efficiency, ion relations, and pigment contents were studied in two seashore
Cakile maritima ecotypes (Tabarka and Jerba, respectively, sampled from humid and arid bioclimatic areas). Growth of Jerba plants was improved
at S100 as compared to S0. Tabarka growth was inhibited by salinity at all NaCl concentrations. Leaf sodium and chloride concentrations increased with
medium salinity and were higher in Jerba than in Tabarka plants. Chlorophyll content, net photosynthetic rate, stomatal conductance
(g
s), and intracellular CO2 concentration were stimulated at moderate salinity (S100) in Jerba plants and inhibited at higher salt concentrations in both ecotypes: g
s was the most reduced parameter. The maximum quantum efficiency of PS2 (Fv/Fm), quantum yield, linear electron transport rate, and efficiency of excitation energy capture by open PS2 reaction centres
showed no significant changes with increasing salt concentration in Jerba plant and were decreased in Tabarka subjected to
S400. However, the efficiency of dissipation of excess photon energy in the PS2 antenna was maintained in Jerba and was increased
in Tabarka plants challenged with S400. Hence the relative salt tolerance of Jerba was associated with a better ability to use Na+ and Cl− for osmotic adjustment, the absence of pigment degradation, and the concomitant PS2 protection from photodamage. 相似文献
10.
Triadimefon, potential fungicide cum plant-growth retardant was used in this study to investigate its effect on the growth and the photosynthetic pigment contents of two varieties of Catharanthus roseus (L.) G. Don. The plants of both varieties were subjected to 15 mg l(-1) triadimefon treatment by soil drenching 30, 45, 60, and 75 days after planting (DAP). Plants were uprooted on 90 DAP, and morphological parameters, like plant height, number of leaves, leaf area, root length and fresh and dry weights were determined. The photosynthetic pigments, like chlorophylls a and b, total chlorophyll, carotenoids, floral pigment, anthocyanin, were extracted and estimated. It was observed that plant height, number of leaves and leaf area were decreased and that root length, fresh and dry weights were increased under triadimefon treatment. The photosynthetic and floral pigments were increased under triadimefon treatment in both varieties. The results suggest that the application of this plant-growth retardant (triadimefon) has favourable effects on the reduction of plant height; it can thus be used for replacing manual hand pruning and for improving floral and vegetation colour in bedding plants like C. roseus. 相似文献