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51.
Aberrant microRNA expression patterns underlie the pathogenesis of diverse diseases, however in a disease as complex as diabetes where the liver exhibits deregulations of normal metabolic processes, the status and role of microRNAs are not yet completely understood. In a step towards unraveling this correlation, we assessed the global microRNA expression profiles in the control and diabetic (db/db) mice liver. These db/db mice were on a C57BLKS/J background and they exhibit diabetic phenotypes that are remarkably similar to those in humans. microRNA microarray profiling revealed 11 miRNAs to be up-regulated and 2 to be down-regulated in the db/db mice liver. Predicted targets of these differentially expressed microRNAs were retrieved from miRanda and TargetScan and the maximum number of commonly predicted targets mapped onto the Wnt signaling pathway that is otherwise conventionally associated with organogenesis and development. Towards validation of this prediction, we found that major components of the Wnt signaling pathway are inhibited in the db/db mice liver. A significant number of these down-regulated genes of the Wnt signaling pathway are predicted targets to the up-regulated miRNAs and specifically our results show that miR-34a and miR-22 decreased the protein levels of their targets. Overexpression of miR-34a and miR-22 and also inhibition of Wnt signaling using specific inhibitors led to increased lipid accumulation in HepG2 cells. Our data suggest that the Wnt signaling pathway could contribute towards the deregulated hepatic behavior in these animals and an altered hepatic miRNA signature could be playing a regulatory role herein. 相似文献
52.
miR-497 and miR-302b regulate ethanol-induced neuronal cell death through BCL2 protein and cyclin D2 总被引:1,自引:0,他引:1
Yadav S Pandey A Shukla A Talwelkar SS Kumar A Pant AB Parmar D 《The Journal of biological chemistry》2011,286(43):37347-37357
In chronic alcoholism, brain shrinkage and cognitive defects because of neuronal death are well established, although the sequence of molecular events has not been fully explored yet. We explored the role of microRNAs (miRNAs) in ethanol-induced apoptosis of neuronal cells. Ethanol-sensitive miRNAs in SH-SY5Y, a human neuroblastoma cell line, were identified using real-time PCR-based TaqMan low-density arrays. Long-term exposure to ethanol (0.5% v/v for 72 h) produced a maximum increase in expression of miR-497 (474-fold) and miR-302b (322-fold). Similar to SH-SY5Y, long-term exposure to ethanol induced miR-497 and miR-302b in IMR-32, another human neuroblastoma cell line. Using in silico approaches, BCL2 and cyclin D2 (CCND2) were identified as probable target genes of these miRNAs. Cotransfection studies with 3'-UTR of these genes and miRNA mimics have demonstrated that BCL2 is a direct target of miR-497 and that CCND2 is regulated negatively by either miR-302b or miR-497. Overexpression of either miR-497 or miR-302b reduced expression of their identified target genes and increased caspase 3-mediated apoptosis of SH-SY5Y cells. However, overexpression of only miR-497 increased reactive oxygen species formation, disrupted mitochondrial membrane potential, and induced cytochrome c release (mitochondria-related events of apoptosis). Moreover, ethanol induced changes in miRNAs, and their target genes were substantially prevented by pre-exposure to GSK-3B inhibitors. In conclusion, our studies have shown that ethanol-induced neuronal apoptosis follows both the mitochondria-mediated (miR-497- and BCL2-mediated) and non-mitochondria-mediated (miR-302b- and CCND2-mediated) pathway. 相似文献
53.
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55.
A composting experiment was conducted to evaluate the effect of a hyperlignocellulolytic fungal consortium and different nitrogen
amendments on paddy straw composting in terms of changes in physicochemical and biological parameters. A fungal consortium
comprising four lignocellulolytic mesophilic fungal cultures was used as inoculum for bioaugmentation of paddy straw in perforated
pits. The comparative effect of farmyard manure (FYM), soybean trash, poultry litter and urea on the composting process was
evaluated at monthly intervals in terms of physicochemical (pH, EC, available P, C:N ratio and humus content) and biological
(enzymatic and microbial activity) parameters. The compost prepared from bioaugmented paddy straw composting mixture, with
poultry manure as nitrogen supplement attained desirable C:N ratio in 1 month and displayed least phytotoxicity levels along
with higher production of β-1,4-Exoglucanase. The combined activity of the autochthonous composting microbiota as well as the externally applied fungal
inoculum accelerated the composting process of paddy straw. Supplementation of paddy straw with poultry manure in 8:1 ratio
was identified as the best treatment to hasten the composting process. This study highlights the importance of application
of fungal inoculum and an appropriate N-amendment such as poultry manure for preparation of compost using a substrate having
high C:N ratio, such as paddy straw. 相似文献
56.
Designing B‐ and T‐cell multi‐epitope based subunit vaccine using immunoinformatics approach to control Zika virus infection 下载免费PDF全文
Rajan Kumar Pandey Rupal Ojha Amit Mishra Vijay Kumar Prajapati 《Journal of cellular biochemistry》2018,119(9):7631-7642
The Zika virus is a rapidly spreading Aedes mosquito‐borne sickness, which creates an unanticipated linkage birth deformity and neurological turmoil. This study represents the use of the combinatorial immunoinformatics approach to develop a multiepitope subunit vaccine using the structural and nonstructural proteins of the Zika virus. The designed subunit vaccine consists of cytotoxic T‐lymphocyte and helper T‐lymphocyte epitopes accompanied by suitable adjuvant and linkers. The presence of humoral immune response specific B‐cell epitopes was also confirmed by B‐cell epitope mapping among vaccine protein. Further, the vaccine protein was characterized for its allergenicity, antigenicity, and physiochemical parameters and found to be safe and immunogenic. Molecular docking and molecular dynamics studies of the vaccine protein with the toll‐like receptor‐3 were performed to ensure the binding affinity and stability of their complex. Finally, in silico cloning was performed for the effective expression of vaccine construct in the microbial system (Escherichia coli K12 strain). Aforementioned approaches result in the multiepitope subunit vaccine which may have the ability to induce cellular as well as humoral immune response. Moreover, this study needs the experimental validation to prove the immunogenic and protective behavior of the developed subunit vaccine. 相似文献
57.
Targeting of the c-Abl tyrosine kinase to mitochondria in endoplasmic reticulum stress-induced apoptosis 总被引:14,自引:0,他引:14 下载免费PDF全文
Ito Y Pandey P Mishra N Kumar S Narula N Kharbanda S Saxena S Kufe D 《Molecular and cellular biology》2001,21(18):6233-6242
The ubiquitously expressed c-Abl tyrosine kinase localizes to the nucleus and cytoplasm. Using confocal microscopy, we demonstrated that c-Abl colocalizes with the endoplasmic reticulum (ER)-associated protein grp78. Expression of c-Abl in the ER was confirmed by immunoelectron microscopy. Subcellular fractionation studies further indicate that over 20% of cellular c-Abl is detectable in the ER. The results also demonstrate that induction of ER stress with calcium ionophore A23187, brefeldin A, or tunicamycin is associated with translocation of ER-associated c-Abl to mitochondria. In concert with targeting of c-Abl to mitochondria, cytochrome c is released in the response to ER stress by a c-Abl-dependent mechanism, and ER stress-induced apoptosis is attenuated in c-Abl-deficient cells. These findings indicate that c-Abl is involved in signaling from the ER to mitochondria and thereby the apoptotic response to ER stress. 相似文献
58.
Ruby Priya Damandeep Kaur Komal Attri Sandeep Kaur Deepinder Sharda Diptiman Choudhury O. P. Pandey 《Luminescence》2024,39(2):e4652
In this article, we have reported the effect of varying concentration of europium (Eu) in (50 − x)% P2O5–25% Na2O–24% CaO–% Eu2O3, where x = 1, 3, 5. The glass samples were synthesised via conventional melt-quench method. The impact of europium ion (Eu3+) on the structural, optical and luminescent properties of phosphate soda lime glasses has been studied using X-ray diffraction (XRD), Fourier-transformed infrared (FTIR) spectroscopy, ultraviolet-visible spectroscopy, scanning electron microscopy coupled with energy-dispersive spectroscopy and photoluminescent techniques. The amorphous nature of glass samples was confirmed by XRD patterns. FTIR confirmed the presence of various functional groups. The emission spectra of synthesised samples exhibited intense emission peaks corresponding to Eu3+ under excitation at 393 nm. Among all the peaks, the maximum intensity was observed for 5D0 → 7F2 transition. Judd–Ofelt (J–O) parameters (Ω2, Ω4) and other radiative parameters such as band width, radiative transition probabilities, stimulated emission cross-sections and branching ratio were determined from emission spectra. The other photometric parameters such as CIE coordinates and colour purity were also determined. Furthermore, cytotoxic studies were carried out on normal cell line human embryonic kidney cells (HEK-293) using MTT assay. Results showed that the prepared samples significantly enhanced growth in glass sample-treated cells as compared to control cells. These findings suggest that synthesised glass samples are biocompatible in nature and have potential for applications in display devices and biomedical research area. 相似文献
59.
Jia Xuan Leong Margot Raffeiner Daniela Spinti Gautier Langin Mirita FranzWachtel Andrew R Guzman JungGun Kim Pooja Pandey Alyona E Minina Boris Macek Anders Hafrn Tolga O Bozkurt Mary Beth Mudgett Frederik Brnke Daniel Hofius Suayib Üstün 《The EMBO journal》2022,41(13)
Beyond its role in cellular homeostasis, autophagy plays anti‐ and promicrobial roles in host–microbe interactions, both in animals and plants. One prominent role of antimicrobial autophagy is to degrade intracellular pathogens or microbial molecules, in a process termed xenophagy. Consequently, microbes evolved mechanisms to hijack or modulate autophagy to escape elimination. Although well‐described in animals, the extent to which xenophagy contributes to plant–bacteria interactions remains unknown. Here, we provide evidence that Xanthomonas campestris pv. vesicatoria (Xcv) suppresses host autophagy by utilizing type‐III effector XopL. XopL interacts with and degrades the autophagy component SH3P2 via its E3 ligase activity to promote infection. Intriguingly, XopL is targeted for degradation by defense‐related selective autophagy mediated by NBR1/Joka2, revealing a complex antagonistic interplay between XopL and the host autophagy machinery. Our results implicate plant antimicrobial autophagy in the depletion of a bacterial virulence factor and unravel an unprecedented pathogen strategy to counteract defense‐related autophagy in plant–bacteria interactions. 相似文献
60.
K B Lee G N La Mar R K Pandey I N Rezzano K E Mansfield K M Smith 《Biochemistry》1991,30(7):1878-1887
1H nuclear magnetic resonance spectroscopy was used to assign the hyperfine-shifted resonances and determine the position of a side chain in the heme cavity of wild-type rat apocytochrome b5 reconstituted with a series of synthetic hemins possessing systematically perturbed carboxylate side chains. The hemins included protohemin derivatives with individually removed or pairwise shortened and lengthened carboxylate side chains, as well as (propionate)n(methyl)8-nporphine-iron(III) isomers with n = 1-3 designed to force occupation of nonnative propionate sites. The resonance assignments were effected on the basis of available empirical heme contact shift correlations and steady-state nuclear Overhauser effect measurements in the low-spin oxidized proteins. The failure to detect holoproteins with certain hemins dictates that the stable holoproteins, unlike the case of myoglobin, demand the axial iron-His bonds and cannot accommodate carboxylate side chains at interior positions in the binding pocket. Hence, the heme pocket interior in cytochrome b5 is judged much less polar and less sterically accommodating than that of myoglobin. The propionate occupational preference was greatest as the native 7-propionate site, but also possible at the nonnative crystallographic 5-methyl or 8-methyl positions. Only for a propionate at the crystallographic 8-methyl position was a significant perturbation of the native molecular/electronic structure observed, and this was attributed to an alternative propionate-protein hydrogen bond at the crystallographic 8-methyl position. The structures of the transient protein complexes detected only shortly after reconstitution reveal that the initial encounter complexes during assembly of holoprotein from apoprotein and hemin involve one of the two alternate propionate-protein links at either the 7-propionate or native 8-methyl position. In a monopropionate hemin, this leads to the characterization of a new type of heme orientational disorder involving rotation about a N-Fe-N axis. 相似文献