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1.
Carlos A. Barrero Prasun K. Datta Satarupa Sen Satish Deshmane Shohreh Amini Kamel Khalili Salim Merali 《PloS one》2013,8(7)
Human immunodeficiency virus type 1 encoded viral protein Vpr is essential for infection of macrophages by HIV-1. Furthermore, these macrophages are resistant to cell death and are viral reservoir. However, the impact of Vpr on the macrophage proteome is yet to be comprehended. The goal of the present study was to use a stable-isotope labeling by amino acids in cell culture (SILAC) coupled with mass spectrometry-based proteomics approach to characterize the Vpr response in macrophages. Cultured human monocytic cells, U937, were differentiated into macrophages and transduced with adenovirus construct harboring the Vpr gene. More than 600 proteins were quantified in SILAC coupled with LC-MS/MS approach, among which 136 were significantly altered upon Vpr overexpression in macrophages. Quantified proteins were selected and clustered by biological functions, pathway and network analysis using Ingenuity computational pathway analysis. The proteomic data illustrating increase in abundance of enzymes in the glycolytic pathway (pentose phosphate and pyruvate metabolism) was further validated by western blot analysis. In addition, the proteomic data demonstrate down regulation of some key mitochondrial enzymes such as glutamate dehydrogenase 2 (GLUD2), adenylate kinase 2 (AK2) and transketolase (TKT). Based on these observations we postulate that HIV-1 hijacks the macrophage glucose metabolism pathway via the Vpr-hypoxia inducible factor 1 alpha (HIF-1 alpha) axis to induce expression of hexokinase (HK), glucose-6-phosphate dehyrogenase (G6PD) and pyruvate kinase muscle type 2 (PKM2) that facilitates viral replication and biogenesis, and long-term survival of macrophages. Furthermore, dysregulation of mitochondrial glutamate metabolism in macrophages can contribute to neurodegeneration via neuroexcitotoxic mechanisms in the context of NeuroAIDS. 相似文献
2.
Harald Sverdrup Salim Belyazid Bengt Nihlg?rd Lars Ericson 《Plant Growth Regulation》1991,10(2):173-174
Book Review
Plant protoplasts and genetic engineering IIY.P.S. Bajaj (Ed.), (Biotechnology in Agriculture and Forestry, Vol. 9). Berlin: Springer-Verlag, 1989. 510 pages. DM398.00. ISBN 3-540-50789-2 相似文献3.
4.
We have sequenced a region of cloned Xenopus laevis ribosomal DNA encompassing the last 24 nucleotides of the external transcribed spacer and the first 275 nucleotides of the 18S gene. The start of the 18S gene was identified by correlating the results obtained from RNA hybridization and fingerprinting with the DNA sequence. This 5' region of 18S rRNA contains five 2'-O-methyl groups and at least six pseudouridine residues. Several of these modified nucleotides are clustered into a relatively short region from nucleotides 99-124. Nucleotides 227-250 constitute a distinctive sequence of 24 consecutive G and C residues. Comparison with the first 160 nucleotides of a yeast 18S gene (25) reveals three blocks of high sequence homology separated by two short tracts where homology is low or absent. The external transcribed spacer sequences diverge widely from within a few nucleotides of the start of the 18S gene. 相似文献
5.
Liu Z Han J Jia L Maillet JC Bai G Xu L Jia Z Zheng Q Zhang W Monette R Merali Z Zhu Z Wang W Ren W Zhang X 《PloS one》2010,5(12):e15634
Drug addiction is an association of compulsive drug use with long-term associative learning/memory. Multiple forms of learning/memory are primarily subserved by activity- or experience-dependent synaptic long-term potentiation (LTP) and long-term depression (LTD). Recent studies suggest LTP expression in locally activated glutamate synapses onto dopamine neurons (local Glu-DA synapses) of the midbrain ventral tegmental area (VTA) following a single or chronic exposure to many drugs of abuse, whereas a single exposure to cannabinoid did not significantly affect synaptic plasticity at these synapses. It is unknown whether chronic exposure of cannabis (marijuana or cannabinoids), the most commonly used illicit drug worldwide, induce LTP or LTD at these synapses. More importantly, whether such alterations in VTA synaptic plasticity causatively contribute to drug addictive behavior has not previously been addressed. Here we show in rats that chronic cannabinoid exposure activates VTA cannabinoid CB1 receptors to induce transient neurotransmission depression at VTA local Glu-DA synapses through activation of NMDA receptors and subsequent endocytosis of AMPA receptor GluR2 subunits. A GluR2-derived peptide blocks cannabinoid-induced VTA synaptic depression and conditioned place preference, i.e., learning to associate drug exposure with environmental cues. These data not only provide the first evidence, to our knowledge, that NMDA receptor-dependent synaptic depression at VTA dopamine circuitry requires GluR2 endocytosis, but also suggest an essential contribution of such synaptic depression to cannabinoid-associated addictive learning, in addition to pointing to novel pharmacological strategies for the treatment of cannabis addiction. 相似文献
6.
GoFigure: automated Gene Ontology annotation 总被引:4,自引:0,他引:4
SUMMARY: We have developed a web tool to predict Gene Ontology (GO) terms. The tool accepts an input DNA or protein sequence, and uses BLAST to identify homologous sequences in GO annotated databases. A graph is returned to the user via email. AVAILABILITY: The tool is freely available at: http://udgenome.ags.udel.edu/frm_go.html/ 相似文献
7.
8.
Juan C. Moreno Jianing Mi Yagiz Alagoz Salim Al-Babili 《The Plant journal : for cell and molecular biology》2021,105(2):351-375
Carotenoids are isoprenoid compounds synthesized by all photosynthetic and some non-photosynthetic organisms. They are essential for photosynthesis and contribute to many other aspects of a plant's life. The oxidative breakdown of carotenoids gives rise to the formation of a diverse family of essential metabolites called apocarotenoids. This metabolic process either takes place spontaneously through reactive oxygen species or is catalyzed by enzymes generally belonging to the CAROTENOID CLEAVAGE DIOXYGENASE family. Apocarotenoids include the phytohormones abscisic acid and strigolactones (SLs), signaling molecules and growth regulators. Abscisic acid and SLs are vital in regulating plant growth, development and stress response. SLs are also an essential component in plants’ rhizospheric communication with symbionts and parasites. Other apocarotenoid small molecules, such as blumenols, mycorradicins, zaxinone, anchorene, β-cyclocitral, β-cyclogeranic acid, β-ionone and loliolide, are involved in plant growth and development, and/or contribute to different processes, including arbuscular mycorrhiza symbiosis, abiotic stress response, plant–plant and plant–herbivore interactions and plastid retrograde signaling. There are also indications for the presence of structurally unidentified linear cis-carotene-derived apocarotenoids, which are presumed to modulate plastid biogenesis and leaf morphology, among other developmental processes. Here, we provide an overview on the biology of old, recently discovered and supposed plant apocarotenoid signaling molecules, describing their biosynthesis, developmental and physiological functions, and role as a messenger in plant communication. 相似文献
9.
Seyed Nezamedin Hosseini Amin Javidanbardan Behnaz Sadat Alizadeh Salim 《Preparative biochemistry & biotechnology》2013,43(8):683-692
AbstractThe costly media, inconsistent ligand density, ligand leakage, and possible destabilization of recombinant hepatitis B surface antigen (rHBsAg) particles are main drawbacks of using immunoaffinity chromatography (IAF) in the large-scale downstream processing. In this study, we aimed to use an efficient large-scale purification system as an alternative purification method for immunoaffinity chromatography. For this purpose, we suggested integrating non-affinity chromatographic methods of hydrophobic interaction chromatography (HIC) and size-exclusion chromatography (SEC) for cost-effective purification of rHBsAg expressed in P. pastoris. The optimization of such process is not trivial and straightforward since diverse molecular characteristics of expressed rHBsAg in each type of host cell cause different interactions in non-affinity chromatography processes. The working buffer composition and chromatography parameters are the most influential factors in hydrophobic interaction chromatography. The best result for lab-scale HIC was achieved by using ammonium sulfate buffer in 10% of saturation concentration in pH 7.0 with Butyl-S Sepharose 6 Fast Flow medium and with subsequent Tween-100 and urea elution. In this process, the recovery, purity, and total yield were about 84%, 82%, and 69%, respectively. By scaling-up the HIC and integrating it with Sephacryl S-400?SEC, we obtained highly pure, i.e.,?>?90%, rHBsAg virus-like particles (VLP). 相似文献
10.
Justus Veerkamp Franziska Rudolph Zoltan Cseresnyes Florian Priller Cécile Otten Marc Renz Liliana Schaefer Salim Abdelilah-Seyfried 《Developmental cell》2013,24(6):660-667
Highlights? Cardiac laterality involves Nodal modulating an antimotogenic Bmp activity ? The Nodal target Hyaluronan synthase 2 unilaterally dampens Bmp signaling activity ? Nonmuscle myosin II is positively regulated by Bmp within cardiac tissue ? High levels of nonmuscle myosin II activity reduce cardiac cell motility 相似文献