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1.
Sci Rep ; 14(1): 16233, 2024 Jul 14.
Article in English | MEDLINE | ID: mdl-39004658

ABSTRACT

Saline-sodic stress restricts the absorption of zinc by rice, consequently impacting the photosynthesis process of rice plants. In this experiment, Landrace 9 was selected as the test material and the potting method was employed to investigate the influence of ZnO nanoparticles (ZnO NPs) on zinc absorption and chlorophyll fluorescence in rice grown in saline-sodic land. The research findings demonstrate that the application of ZnO NPs proves to be more advantageous for the growth of rice in saline-sodic soil. Notably, the application of ZnO NPs significantly decreases the levels of Na+ and MDA in rice leaves in saline-sodic soil, while increasing the levels of K+ and Zn2+. Additionally, ZnO NPs enhances the content of chloroplast pigments, specific energy flux, quantum yield, and the performance of active PSII reaction center (PIABS) in rice leaves under saline-sodic stress. Furthermore, the relative variable fluorescence (WK and VJ) and quantum energy dissipation rate (φDo) of rice are also reduced. Therefore, the addition of ZnO NPs enhances the transfer of electrons and energy within the rice photosystem when subjected to saline-sodic stress. This promotes photosynthesis in rice plants growing in saline-sodic land, increasing their resistance to saline-sodic stress and ultimately facilitating their growth and development.


Subject(s)
Oryza , Photosynthesis , Plant Leaves , Soil , Zinc Oxide , Oryza/metabolism , Oryza/drug effects , Oryza/growth & development , Zinc Oxide/pharmacology , Photosynthesis/drug effects , Plant Leaves/metabolism , Plant Leaves/drug effects , Soil/chemistry , Chlorophyll/metabolism , Photosystem II Protein Complex/metabolism , Metal Nanoparticles/chemistry , Fluorescence , Salinity
2.
Front Neurol ; 11: 584695, 2020.
Article in English | MEDLINE | ID: mdl-33193047

ABSTRACT

Genome-wide association studies have identified putative ischemic stroke risk genes, yet, their expression after stroke is unexplored in spite of growing interest in elucidating their specific role and identifying candidate genes for stroke treatment. Thus, we took an exploratory approach to investigate sexual dimorphism, alternative splicing, and etiology in putative risk gene expression in blood following cardioembolic, atherosclerotic large vessel disease and small vessel disease/lacunar causes of ischemic stroke in each sex compared to controls. Whole transcriptome arrays assessed 71 putative stroke/vascular risk factor genes for blood RNA expression at gene-, exon-, and alternative splicing-levels. Male (n = 122) and female (n = 123) stroke and control volunteers from three university medical centers were matched for race, age, vascular risk factors, and blood draw time since stroke onset. Exclusion criteria included: previous stroke, drug abuse, subarachnoid or intracerebral hemorrhage, hemorrhagic transformation, infection, dialysis, cancer, hematological abnormalities, thrombolytics, anticoagulants or immunosuppressants. Significant differential gene expression (fold change > |1.2|, p < 0.05, partial correlation > |0.4|) and alternative splicing (false discovery rate p < 0.3) were assessed. At gene level, few were differentially expressed: ALDH2, ALOX5AP, F13A1, and IMPA2 (males, all stroke); ITGB3 (females, cardioembolic); ADD1 (males, atherosclerotic); F13A1, IMPA2 (males, lacunar); and WNK1 (females, lacunar). GP1BA and ITGA2B were alternatively spliced in both sexes (all patients vs. controls). Six genes in males, five in females, were alternatively spliced in all stroke compared to controls. Alternative splicing and exon-level analyses associated many genes with specific etiology in either sex. Of 71 genes, 70 had differential exon-level expression in stroke patients compared to control subjects. Among stroke patients, 24 genes represented by differentially expressed exons were male-specific, six were common between sexes, and two were female-specific. In lacunar stroke, expression of 19 differentially expressed exons representing six genes (ADD1, NINJ2, PCSK9, PEMT, SMARCA4, WNK1) decreased in males and increased in females. Results demonstrate alternative splicing and sexually dimorphic expression of most putative risk genes in stroke patients' blood. Since expression was also often cause-specific, sex, and etiology are factors to consider in stroke treatment trials and genetic association studies as society trends toward more personalized medicine.

3.
J Cereb Blood Flow Metab ; 40(4): 775-786, 2020 04.
Article in English | MEDLINE | ID: mdl-30966854

ABSTRACT

Previous studies showed changes in mRNA levels in whole blood of rats and humans, and in miRNA in whole blood of rats following intracerebral hemorrhage (ICH). Thus, this study assessed miRNA and their putative mRNA targets in whole blood of humans following ICH. Whole transcriptome profiling identified altered miRNA and mRNA levels in ICH patients compared to matched controls. Target mRNAs of the differentially expressed miRNAs were identified, and functional analysis of the miRNA-mRNA targets was performed. Twenty-nine miRNAs (22 down, 7 up) and 250 target mRNAs (136 up, 114 down), and 7 small nucleolar RNA changed expression after ICH compared to controls (FDR < 0.05, and fold change ≥ |1.2|). These included Let7i, miR-146a-5p, miR210-5p, miR-93-5p, miR-221, miR-874, miR-17-3p, miR-378a-5p, miR-532-5p, mir-4707, miR-4450, mir-1183, Let-7d-3p, miR-3937, miR-4288, miR-4741, miR-92a-1-3p, miR-4514, mir-4658, mir-3689d-1, miR-4760-3p, and mir-3183. Pathway analysis showed regulated miRNAs/mRNAs were associated with toll-like receptor, natural killer cell, focal adhesion, TGF-ß, phagosome, JAK-STAT, cytokine-cytokine receptor, chemokine, apoptosis, vascular smooth muscle, and RNA degradation signaling. Many of these pathways have been implicated in ICH. The differentially expressed miRNA and their putative mRNA targets and associated pathways may provide diagnostic biomarkers as well as point to therapeutic targets for ICH treatments in humans.


Subject(s)
Cerebral Hemorrhage/blood , MicroRNAs/blood , RNA, Messenger/blood , Transcriptome , Aged , Apoptosis/genetics , Cerebral Hemorrhage/genetics , Cerebral Hemorrhage/pathology , Down-Regulation , Female , Gene Expression Profiling , Humans , Male , MicroRNAs/genetics , Middle Aged , RNA, Messenger/genetics , Up-Regulation
4.
Ann Clin Transl Neurol ; 6(9): 1748-1756, 2019 09.
Article in English | MEDLINE | ID: mdl-31436916

ABSTRACT

OBJECTIVE: Though cigarette smoking (CS) is a well-known risk factor for ischemic stroke (IS), there is no data on how CS affects the blood transcriptome in IS patients. METHODS: We recruited IS-current smokers (IS-SM), IS-never smokers (IS-NSM), control-smokers (C-SM), and control-never smokers (C-NSM). mRNA expression was assessed on HTA-2.0 microarrays and unique as well as commonly expressed genes identified for IS-SM versus IS-NSM and C-SM versus C-NSM. RESULTS: One hundred and fifty-eight genes were differentially expressed in IS-SM versus IS-NSM; 100 genes were differentially expressed in C-SM versus C-NSM; and 10 genes were common to both IS-SM and C-SM (P < 0.01; |fold change| ≥ 1.2). Functional pathway analysis showed the 158 IS-SM-regulated genes were associated with T-cell receptor, cytokine-cytokine receptor, chemokine, adipocytokine, tight junction, Jak-STAT, ubiquitin-mediated proteolysis, and adherens junction signaling. IS-SM showed more altered genes and functional networks than C-SM. INTERPRETATION: We propose some of the 10 genes that are elevated in both IS-SM and C-SM (GRP15, LRRN3, CLDND1, ICOS, GCNT4, VPS13A, DAP3, SNORA54, HIST1H1D, and SCARNA6) might contribute to increased risk of stroke in current smokers, and some genes expressed by blood leukocytes and platelets after stroke in smokers might contribute to worse stroke outcomes that occur in smokers.


Subject(s)
Brain Ischemia/genetics , Cigarette Smoking/genetics , Gene Expression , Stroke/genetics , Adult , Aged , Blood Platelets/metabolism , Brain Ischemia/blood , Cigarette Smoking/blood , Female , Humans , Leukocytes/metabolism , Male , Middle Aged , Stroke/blood , Transcriptome
5.
J Neuroinflammation ; 16(1): 56, 2019 Mar 05.
Article in English | MEDLINE | ID: mdl-30836997

ABSTRACT

BACKGROUND: Intracerebral hemorrhage (ICH) has a high morbidity and mortality. The peripheral immune system and cross-talk between peripheral blood and brain have been implicated in the ICH immune response. Thus, we delineated the gene networks associated with human ICH in the peripheral blood transcriptome. We also compared the differentially expressed genes in blood following ICH to a prior human study of perihematomal brain tissue. METHODS: We performed peripheral blood whole-transcriptome analysis of ICH and matched vascular risk factor control subjects (n = 66). Gene co-expression network analysis identified groups of co-expressed genes (modules) associated with ICH and their most interconnected genes (hubs). Mixed-effects regression identified differentially expressed genes in ICH compared to controls. RESULTS: Of seven ICH-associated modules, six were enriched with cell-specific genes: one neutrophil module, one neutrophil plus monocyte module, one T cell module, one Natural Killer cell module, and two erythroblast modules. The neutrophil/monocyte modules were enriched in inflammatory/immune pathways; the T cell module in T cell receptor signaling genes; and the Natural Killer cell module in genes regulating alternative splicing, epigenetic, and post-translational modifications. One erythroblast module was enriched in autophagy pathways implicated in experimental ICH, and NRF2 signaling implicated in hematoma clearance. Many hub genes or module members, such as IARS, mTOR, S1PR1, LCK, FYN, SKAP1, ITK, AMBRA1, NLRC4, IL6R, IL17RA, GAB2, MXD1, PIK3CD, NUMB, MAPK14, DDX24, EVL, TDP1, ATG3, WDFY3, GSK3B, STAT3, STX3, CSF3R, PIP4K2A, ANXA3, DGAT2, LRP10, FLOT2, ANK1, CR1, SLC4A1, and DYSF, have been implicated in neuroinflammation, cell death, transcriptional regulation, and some as experimental ICH therapeutic targets. Gene-level analysis revealed 1225 genes (FDR p < 0.05, fold-change > |1.2|) have altered expression in ICH in peripheral blood. There was significant overlap of the 1225 genes with dysregulated genes in human perihematomal brain tissue (p = 7 × 10-3). Overlapping genes were enriched for neutrophil-specific genes (p = 6.4 × 10-08) involved in interleukin, neuroinflammation, apoptosis, and PPAR signaling. CONCLUSIONS: This study delineates key processes underlying ICH pathophysiology, complements experimental ICH findings, and the hub genes significantly expand the list of novel ICH therapeutic targets. The overlap between blood and brain gene responses underscores the importance of examining blood-brain interactions in human ICH.


Subject(s)
Autophagy/physiology , Cerebral Hemorrhage , Cytokines/metabolism , Gene Expression Regulation/physiology , Gene Regulatory Networks , Signal Transduction/physiology , Case-Control Studies , Cerebral Hemorrhage/genetics , Cerebral Hemorrhage/immunology , Cerebral Hemorrhage/pathology , Cytokines/genetics , Female , Gene Expression Profiling , Humans , Immune System , Male , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , Transcriptome/physiology
6.
J Cereb Blood Flow Metab ; 39(9): 1818-1835, 2019 09.
Article in English | MEDLINE | ID: mdl-29651892

ABSTRACT

Understanding how the blood transcriptome of human intracerebral hemorrhage (ICH) differs from ischemic stroke (IS) and matched controls (CTRL) will improve understanding of immune and coagulation pathways in both disorders. This study examined RNA from 99 human whole-blood samples using GeneChip® HTA 2.0 arrays to assess differentially expressed transcripts of alternatively spliced genes between ICH, IS and CTRL. We used a mixed regression model with FDR-corrected p(Dx) < 0.2 and p < 0.005 and |FC| > 1.2 for individual comparisons. For time-dependent analyses, subjects were divided into four time-points: 0(CTRL), <24 h, 24-48 h, >48 h; 489 transcripts were differentially expressed between ICH and CTRL, and 63 between IS and CTRL. ICH had differentially expressed T-cell receptor and CD36 genes, and iNOS, TLR, macrophage, and T-helper pathways. IS had more non-coding RNA. ICH and IS both had angiogenesis, CTLA4 in T lymphocytes, CD28 in T helper cells, NFAT regulation of immune response, and glucocorticoid receptor signaling pathways. Self-organizing maps revealed 4357 transcripts changing expression over time in ICH, and 1136 in IS. Understanding ICH and IS transcriptomes will be useful for biomarker development, treatment and prevention strategies, and for evaluating how well animal models recapitulate human ICH and IS.


Subject(s)
Brain Ischemia/genetics , Cerebral Hemorrhage/genetics , Stroke/genetics , Transcriptome , Aged , Alternative Splicing , Brain Ischemia/blood , Cerebral Hemorrhage/blood , Female , Humans , Male , Middle Aged , Stroke/blood
7.
Front Neurosci ; 12: 767, 2018.
Article in English | MEDLINE | ID: mdl-30405345

ABSTRACT

Aim: Our previous study demonstrated miR-122 mimic decreased NOS2 expression in blood leucocytes and improved stroke outcomes when given immediately after middle cerebral artery occlusion (MCAO) in rats. Since NOS2 is associated with neuro-inflammation in stroke and decreasing NOS2 expression alone in leucocytes is insufficient to improve stroke outcomes, we hypothesized that miR-122 mimic may also decrease NOS2 expression in brain microvascular endothelial cells (BMVECs) even at extended time windows. Methods: We administered PEG-liposome wrapped miR-122 mimic (2.4 mg/kg, i.v.) 0 or 6 h after MCAO, and assessed stroke volume and NOS2 expression in BMVECs 24 h following MCAO in rats. Luciferase reporter assays were used to determine if miR-122 binds to 3' untranslated regions (3'UTR) of NOS2. Results: The data showed that miR-122 mimic decreased infarct volumes and decreased MCAO-induced NOS2 over-expression in BMVECs. However, miR-122 did not bind to 3'UTR of NOS2 in the luciferase assays. Conclusion: The data show the 6-h period of therapeutic efficacy of miR-122 mimic which could relate to indirect knockdown of NOS2 in both BMVECs and leucocytes.

8.
Adv Mater ; 30(8)2018 Feb.
Article in English | MEDLINE | ID: mdl-29271507

ABSTRACT

The photoactuation of pen arrays made of polydimethylsiloxane carbon nanotube composites is explored, and the first demonstration of photoactuated pens for molecular printing is reported. Photoactuation of these composites is characterized using atomic force microscopy and found to produce microscale motion in response to modest illumination, with an actuation efficiency as high as 200 nm mW-1 on the sub-1 s time scale. Arrays of composite pens are synthesized and it is found that local illumination is capable of moving selected pens by more than 3 µm out of the plane, bringing them into contact to perform controllable and high quality printing while completely shutting off the nonilluminated counterparts. In light of the scalability limitations of nanolithography, this work presents an important step and paves the way for arbitrary control of individual pens in massive arrays. As an example of a scalable soft actuator, this approach can also aid progress in other fields such as soft robotics and microfluidics.

9.
Nano Lett ; 16(9): 5875-82, 2016 09 14.
Article in English | MEDLINE | ID: mdl-27518908

ABSTRACT

Bismuth is a lithium-ion battery anode material that can operate at an equilibrium potential higher than graphite and provide a capacity twice as high as that of Li4Ti5O12, making it intrinsically free from lithium plating that may cause catastrophic battery failure. However, the potential of bismuth is hampered by its inferior cyclability (limited to tens of cycles). Here, we propose an "ion conductive solid-state matrix" approach to address this issue. By homogeneously confining bismuth nanoparticles in a solid-state γ-Li3PO4 matrix that is electrochemically formed in situ, the resulting composite anode exhibits a reversible capacity of 280 mA hours per gram (mA h/g) at a rate of 100 mA/g and a record cyclability among bismuth-based anodes up to 500 cycles with a capacity decay rate of merely 0.071% per cycle. We further show that full-cell batteries fabricated from this composite anode and commercial LiFePO4 cathode deliver a stable cell voltage of ∼2.5 V and remarkable energy efficiency up to 86.3%, on par with practical batteries (80-90%). This work paves a way for harnessing bismuth-based battery chemistry for the design of high capacity, safer lithium-ion batteries to meet demanding applications such as electric vehicles.

10.
Adv Mater ; 28(31): 6672-9, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27214267

ABSTRACT

The selective growth of Al2 O3 islands over defect sites on the surface of carbon nanotubes significantly increases the oxidation breakdown threshold to 6.8 W cm(-2) , more than double than that of unprotected films. The elevated input power enables thermoacoustic emissions at loud audible sound pressure levels of 90.1 dB, which are inaccessible with the unprotected films.

11.
J Hazard Mater ; 261: 83-90, 2013 Oct 15.
Article in English | MEDLINE | ID: mdl-23912074

ABSTRACT

A novel functional ionic liquid based cross-linked polymer (PDVB-IL) was synthesized from 1-aminoethyl-3-vinylimidazolium chloride and divinylbenzene for use as an adsorbent. The physicochemical properties of PDVB-IL were investigated by Fourier transform infrared spectroscopy, scanning electron microscopy and thermogravimetric analysis. The adsorptive capacity was investigated using anionic azo dyes of orange II, sunset yellow FCF, and amaranth as adsorbates. The maximum adsorption capacity could reach 925.09, 734.62, and 547.17 mg/g for orange II, sunset yellow FCF and amaranth at 25°C, respectively, which are much better than most of the other adsorbents reported earlier. The effect of pH value was investigated in the range of 1-8. The result shows that a low pH value is found to favor the adsorption of those anionic azo dyes. The adsorption kinetics and isotherms are well fitted by a pseudo second-order model and Langmuir model, respectively. The adsorption process is found to be dominated by physisorption. The introduction of functional ionic liquid moieties into cross-linked poly(divinylbenzene) polymer constitutes a new and efficient kind of adsorbent.


Subject(s)
Amaranth Dye/chemistry , Azo Compounds/chemistry , Benzenesulfonates/chemistry , Coloring Agents/chemistry , Imidazoles/chemistry , Water Pollutants, Chemical/chemistry , Adsorption , Hydrogen-Ion Concentration , Ionic Liquids/chemistry , Kinetics , Solutions , Water Purification/methods
12.
Langmuir ; 29(21): 6213-20, 2013 May 28.
Article in English | MEDLINE | ID: mdl-23642150

ABSTRACT

The effects of ionic liquids (ILs), 1-butyl-3-methylimidazolium methylsulfonate (bmimMsa), 1-butyl-3-methylimidazolium benzenesulfonate (bmimBsa), and 1-butyl-3-methylimidazolium 2-naphthalenesulfonate (bmimNsa), on the aggregation behavior of 1-dodecyl-3-methylimidazolium bromide (C12mimBr) in aqueous solution were investigated by surface tension, dynamic light scattering measurements, and (1)H NMR spectroscopy. The ability to promote the surfactant aggregation is in the order bmimNsa > bmimBsa > bmimMsa. Nevertheless, only bmimNsa distinctly reduces both the CMC value and the surface tension at CMC. Due to the penetration of C10H7SO3(-)anions into the surfactant aggregate, bmimNsa is found to induce a phase transition from micelles to vesicles, whereas the other ILs only slightly increase the sizes of micelles. The combined effect of intermolecular interactions, such as hydrophobic effect, electrostatic attractions, and π-π stacking interactions, is supposed to be responsible for this structural transformation, in which π-π stacking plays an important role.


Subject(s)
Hydrocarbons, Aromatic/chemistry , Imidazoles/chemistry , Ionic Liquids/chemistry , Anions/chemistry , Molecular Structure , Particle Size , Solutions , Surface Tension , Water/chemistry
13.
Neurobiol Dis ; 30(2): 201-11, 2008 May.
Article in English | MEDLINE | ID: mdl-18343677

ABSTRACT

Since Src kinase inhibitors decrease brain injury produced by intracerebral hemorrhage (ICH) and thrombin is activated following ICH, this study determined whether Src kinase inhibitors decrease thrombin-induced brain injury. Thrombin injections into adult rat striatum produced focal infarction and motor deficits. The Src kinase inhibitor PP2 decreased thrombin-induced Src activation, infarction in striatum and motor deficits in vivo. Thrombin applied to cultured post-mitotic striatal neurons caused: injury to axons and dendrites; many TUNEL positive neuronal nuclei; and re-entry into the cell cycle as manifested by cyclin D1 expression, induction of several other cell cycle genes and cyclin-dependent kinase 4 activation. PP2 dose-dependently attenuated thrombin-induced injury to the cultured neurons; and attenuated thrombin-induced neuronal cell cycle re-entry. These results are consistent with the hypotheses that Src kinase inhibitors decrease injury produced by ICH by decreasing thrombin activation of Src kinases and, at least in part, by decreasing Src induced cell cycle re-entry.


Subject(s)
Cell Cycle/physiology , Corpus Striatum/enzymology , Corpus Striatum/pathology , Neurons/enzymology , Neurons/pathology , Thrombin/toxicity , src-Family Kinases/antagonists & inhibitors , Animals , Cell Cycle/drug effects , Cell Differentiation/drug effects , Cell Differentiation/physiology , Cells, Cultured , Corpus Striatum/drug effects , Male , Neurons/drug effects , Protein Kinase Inhibitors/pharmacology , Rats , Rats, Sprague-Dawley , src-Family Kinases/metabolism
14.
Mol Pharmacol ; 66(5): 1213-22, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15308762

ABSTRACT

Formyl peptide receptor-like 1 (FPRL1) is a G protein-coupled receptor that binds natural and synthetic peptides as well as lipoxin A(4) and mediates important biological functions. To facilitate its pharmacological characterization, we screened a compound library and identified a substituted quinazolinone (Quin-C1, 4-butoxy-N-[2-(4-methoxy-phenyl)-4-oxo-1,4-dihydro-2H-quinazolin-3-yl]-benzamide) as a ligand for FPRL1. Quin-C1 induces chemotaxis and secretion of beta-glucuronidase in peripheral blood neutrophils with a potency of approximately 1/1000 of that of the peptide agonist WKYMVm. In studies using transfected rat basophilic leukemia (RBL) cell lines expressing either formyl peptide receptor or FPRL1, Quin-C1 induced enzyme release from RBL-FPRL1 but not RBL-FPR cells. Likewise, Quin-C1 selectively stimulates calcium mobilization in RBL-FPRL1 cells, a response that was markedly inhibited by pertussis toxin. Quin-C1 also stimulates phosphorylation of extracellular signal-regulated protein kinases 1 and 2 and induces internalization of an FPRL1 fused to green fluorescent protein. In degranulation assays, both the FPRL1-selective peptide agonist MMK1 and Quin-C1 exhibited lower efficacy and potency than WKYMVm, with EC(50) values of 7.17 x 10(-8) M and 1.88 x 10(-6) M, respectively, compared with the EC(50) value for WKYMVm (2.29 x 10(-8) M). However, Quin-C1 did not induce neutrophil superoxide generation at up to 100 microM. Based on these results, we conclude that Quin-C1 is a novel nonpeptide ligand that binds to FPRL1 and selectively stimulates FPRL1-mediated functions. Quin-C1 is a prototype of substituted quinazolinones based on which further structural modifications may be made to improve its efficacy and potency for FPRL1.


Subject(s)
Benzamides/pharmacology , Neutrophils/drug effects , Quinazolines/pharmacology , Receptors, Formyl Peptide/agonists , Animals , Benzamides/chemical synthesis , Cell Line , Chemotaxis/drug effects , Drug Interactions , Endocytosis/drug effects , GTP-Binding Protein alpha Subunits, Gi-Go/physiology , Glucuronidase/metabolism , Humans , Ligands , Mitogen-Activated Protein Kinases/metabolism , Neutrophils/metabolism , Oligopeptides/pharmacology , Phosphorylation/drug effects , Quinazolines/chemical synthesis , Rats , Receptors, Formyl Peptide/metabolism , Signal Transduction/drug effects , Superoxides/metabolism , Tumor Cells, Cultured
15.
Acta Pharmacol Sin ; 24(1): 91-6, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12511235

ABSTRACT

AIM: To study the effects of transcriptional factor Sp1 antisense oligodeoxynucleotide (ODN) on telomerase activity and human telomerase reverse transcriptase (hTERT) expression. METHODS: Antisense oligodeoxynucleotide (ODN) was designed to inhibit Sp1 expression and transferred to Jurkat T cells by lipofectamin. Telomerase PCR-ELISA was used to detect telomerase activity. RT-PCR analysis was used to assess the mRNA expression of Sp1 and hTERT, and Western blot was used to analyze the levels of Sp1 protein. RESULTS: Treatment of Jurkat T cells with Sp1 antisense ODN (1 micromol/L) dramatically reduced Sp1 mRNA and protein levels. The inhibition rate was 44.8 % (P <0.05) and 57 % (P <0.01), respectively. Following the transcriptional factor Sp1 functionally altering, hTERT mRNA expression were suppressed with a 43.7 % inhibition rate (P <0.01). A dose-dependent inhibition of telomerase activity by antisense Sp1 ODN was also discovered. From 0.25 to 2.0 micromol/L, telomerase activity was reduced from 27.1 % to 64.6 %. CONCLUSION: Antisense Sp1 ODN decreases telomerase activity by inhibiting hTERT mRNA expression in Jurkat T cells.


Subject(s)
DNA, Antisense/pharmacology , Sp1 Transcription Factor/antagonists & inhibitors , Telomerase/antagonists & inhibitors , Telomerase/metabolism , DNA-Binding Proteins , Humans , Jurkat Cells/enzymology , RNA, Messenger/biosynthesis , RNA, Messenger/drug effects , Sp1 Transcription Factor/genetics , Telomerase/genetics
16.
Yi Chuan ; 24(6): 675-8, 2002 Nov.
Article in Chinese | MEDLINE | ID: mdl-15979968

ABSTRACT

Our project is designed to clone a 1.3kb gene fragment of telomerase catalytic subunit gene which contains seven reverse transcriptase motifs and specific region with conserved sequence termed "T motif". The gene fragment was amplified by PCR and was inserted into expression vector pET28-b. The recombinant plasmid was induced by IPTG for 4h and a 52KD recombinant protein was produced. Amount of hTRT recombinant protein expression was 20% of total bacterial protein in the form of inclusion. Inclusion was dissolved in 8 mol/L urea and 10 mmol/L DTT and carried out affinity purification under denaturing condition. The purified hTRT recombinant protein was conformed by Western-blot successfully.

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