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Yang S, Wei K, Ma W, Xie K, Wu J, Lei Y. Kinetic mechanism of aluminum removal from diamond wire saw powder in HCl solution. JOURNAL OF HAZARDOUS MATERIALS 2019; 368:1-9. [PMID: 30658158 DOI: 10.1016/j.jhazmat.2019.01.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 12/21/2018] [Accepted: 01/10/2019] [Indexed: 06/09/2023]
Abstract
Impurity removal is essential for the recovery and regeneration of silicon resources from diamond wire saw powder by metallurgical purification technologies. In this paper, the aluminum was removed from the diamond wire saw powder via a direct HCl leaching method. In order to analyze the removal efficiency of various experimental conditions, certain parameters such as HCl concentration, leaching temperature, reaction time and liquid-solid ratio were also investigated. Particularly, the removal efficiency of Al reached 95.6% under the optimal leaching condition, such as the HCl concentration of 4 mol·L-1, the leaching temperature of 60 °C, the reaction time of 3 h, and the liquid-solid ratio of 10. The shrinking core model and homogeneous model were then respectively utilized to describe the leaching kinetics of the Al removal leaching process. The results indicated that the homogeneous model was more suitable than the shrinking core model. Moreover, the kinetics parameters regarding the reaction orders m=3, n=2.81, the activation energy Ea=97.30kJmol-1, the frequency factor A=1.11×1014 min-1. Furthermore, the leaching mechanism of Al removal was revealed based on kinetic analysis and materials characterization. This work is of great practical value in terms of regenerating silicon resources from the diamond wire saw powder waste materials with efficient and low cost methods.
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Sun GY, Xie K, Sun ZY, Sun MY, Li N. Sevoflurane induces temporary spatial working memory deficits and synaptic ultrastructure impairments in the hippocampus of neonatal rats. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2019; 23:2620-2629. [PMID: 30964191 DOI: 10.26355/eurrev_201903_17412] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Exposure to volatile anesthetics in neonatal rats could induce neurotoxicity, learning deficits and abnormal social behaviors. The aim of this study is to investigate the potential neurotoxicity induced by sevoflurane. MATERIALS AND METHODS Postnatal day 7 (P7) Sprague-Dawley (SD) rats were continuously exposed to 2% sevoflurane plus 40% oxygen/air for 2 h. We used Morris water maze (MWM) to examine subsequent neurobehavioral performance. Transmission electron microscopy (TEM) was used to observe the histopathological changes in the hippocampus. RESULTS Neonatal exposure to 2% sevoflurane for 2 hours impaired short-term spatial working memory but not reference memory at P25. It induced synaptic ultrastructure impairments in the CA3 region of hippocampal, including fewer numbers of synapses, thinner thickness of postsynaptic dense, broader synaptic cleft width and smaller synaptic curvature. Our results also showed that all synaptic ultrastructure impairments and neurocognitive deficits had almost completely recovered at P53. CONCLUSIONS We showed that a single sevoflurane exposure to neonatal rats led to temporary spatial working memory deficits. It might be associated with synaptic ultrastructure impairments in the CA3 region of the hippocampus, including fewer numbers of synapses, thinner thickness of PSD and broader synaptic cleft width. Fortunately, all the neurotoxicity and neurocognitive deficits were reversible.
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Zhu M, Wang L, Yang J, Xie K, Zhu M, Liu S, Xu C, Wang J, Gu L, Ni Z, Xu G, Che M. Erythropoietin Ameliorates Lung Injury by Accelerating Pulmonary Endothelium Cell Proliferation via Janus Kinase-Signal Transducer and Activator of Transcription 3 Pathway After Kidney Ischemia and Reperfusion Injury. Transplant Proc 2019; 51:972-978. [PMID: 30979490 DOI: 10.1016/j.transproceed.2019.01.059] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 11/19/2018] [Accepted: 01/17/2019] [Indexed: 12/11/2022]
Abstract
BACKGROUND/AIMS Kidney ischemia and reperfusion injury could cause microvascular barrier dysfunction, lung inflammatory cascades activation, and programmed cell death of pulmonary endothelium, leading to acute lung injury. Our study aimed at determining whether erythropoietin (EPO) can ameliorate lung dysfunction following renal ischemia and reperfusion (IR) injury and explored the underlying mechanisms. METHODS In vivo, C57BL/6 mice received EPO (6000 U/kg) before right renal vascular pedicles clamping for 30 minutes, followed by 24 hours of reperfusion. The lung histopathologic changes and inflammatory cytokines expression were assessed. In vitro, cultured human umbilical vein endothelial cells were treated with EPO, and apoptosis rate, proliferation capacity, and phosphorylation status of the Janus kinase-signal transducer and activator of transcription 3 (Jak-STAT3) pathway were measured respectively in the presence or absence of lipopolysaccharide stimulation. RESULTS In vivo, EPO remarkably attenuated pulmonary interstitial and alveolar epithelial edema caused by renal IR injury. In vitro, the proliferation capacity of human umbilical vein endothelial cells was significantly increased under EPO stimulation, which correlated with changes in Jak-STAT3 signaling. CONCLUSION Our data indicated that EPO is able to ameliorate acute lung tissue damage induced by renal IR, and at least in part, via the Jak-STAT3 pathway.
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Zhang P, Xie K, Huang X, Li C, Song Y, Li B, Liao W, Zhang S. Early Nutrition Support Therapy to Improve the Nutrition Status of Head and Neck Cancer Patients Accepted Concurrent Chemoradiotherapy(NSTIP):Interim Analysis from a Prospective Randomized Controlled Clinical Study. Int J Radiat Oncol Biol Phys 2018. [DOI: 10.1016/j.ijrobp.2018.07.1988] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Zhang P, Xie K, Huang X, Li C, Song Y. The Prognostic Factors of Metastatic Nasopharyngeal Carcinoma at Initial Diagnosis: A Retrospective Analysis. Int J Radiat Oncol Biol Phys 2018. [DOI: 10.1016/j.ijrobp.2018.07.1132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Wu J, Yang D, Xu M, Ma W, Zhou Q, Xia Z, Lei Y, Wei K, Li S, Chen Z, Xie K. Boron Removal from Silicon Using Secondary Refining Techniques by Metallurgical Method. SEPARATION AND PURIFICATION REVIEWS 2018. [DOI: 10.1080/15422119.2018.1523191] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Ryan DP, Henzel KS, Pearson BL, Siwek ME, Papazoglou A, Guo L, Paesler K, Yu M, Müller R, Xie K, Schröder S, Becker L, Garrett L, Hölter SM, Neff F, Rácz I, Rathkolb B, Rozman J, Ehninger G, Klingenspor M, Klopstock T, Wolf E, Wurst W, Zimmer A, Fuchs H, Gailus-Durner V, Hrabě de Angelis M, Sidiropoulou K, Weiergräber M, Zhou Y, Ehninger D. A paternal methyl donor-rich diet altered cognitive and neural functions in offspring mice. Mol Psychiatry 2018; 23:1345-1355. [PMID: 28373690 PMCID: PMC5984088 DOI: 10.1038/mp.2017.53] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 02/13/2017] [Accepted: 02/14/2017] [Indexed: 12/17/2022]
Abstract
Dietary intake of methyl donors, such as folic acid and methionine, shows considerable intra-individual variation in human populations. While it is recognized that maternal departures from the optimum of dietary methyl donor intake can increase the risk for mental health issues and neurological disorders in offspring, it has not been explored whether paternal dietary methyl donor intake influences behavioral and cognitive functions in the next generation. Here, we report that elevated paternal dietary methyl donor intake in a mouse model, transiently applied prior to mating, resulted in offspring animals (methyl donor-rich diet (MD) F1 mice) with deficits in hippocampus-dependent learning and memory, impaired hippocampal synaptic plasticity and reduced hippocampal theta oscillations. Gene expression analyses revealed altered expression of the methionine adenosyltransferase Mat2a and BK channel subunit Kcnmb2, which was associated with changes in Kcnmb2 promoter methylation in MD F1 mice. Hippocampal overexpression of Kcnmb2 in MD F1 mice ameliorated altered spatial learning and memory, supporting a role of this BK channel subunit in the MD F1 behavioral phenotype. Behavioral and gene expression changes did not extend into the F2 offspring generation. Together, our data indicate that paternal dietary factors influence cognitive and neural functions in the offspring generation.
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Sutton LP, Orlandi C, Song C, Oh WC, Muntean BS, Xie K, Filippini A, Xie X, Satterfield R, Yaeger JDW, Renner KJ, Young SM, Xu B, Kwon H, Martemyanov KA. Orphan receptor GPR158 controls stress-induced depression. eLife 2018; 7:33273. [PMID: 29419376 PMCID: PMC5823542 DOI: 10.7554/elife.33273] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 02/06/2018] [Indexed: 01/23/2023] Open
Abstract
Stress can be a motivational force for decisive action and adapting to novel environment; whereas, exposure to chronic stress contributes to the development of depression and anxiety. However, the molecular mechanisms underlying stress-responsive behaviors are not fully understood. Here, we identified the orphan receptor GPR158 as a novel regulator operating in the prefrontal cortex (PFC) that links chronic stress to depression. GPR158 is highly upregulated in the PFC of human subjects with major depressive disorder. Exposure of mice to chronic stress also increased GPR158 protein levels in the PFC in a glucocorticoid-dependent manner. Viral overexpression of GPR158 in the PFC induced depressive-like behaviors. In contrast GPR158 ablation, led to a prominent antidepressant-like phenotype and stress resiliency. We found that GPR158 exerts its effects via modulating synaptic strength altering AMPA receptor activity. Taken together, our findings identify a new player in mood regulation and introduce a pharmacological target for managing depression.
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Gedling CR, Ali EM, Gunadi A, Finer JJ, Xie K, Liu Y, Yoshikawa N, Qu F, Dorrance AE. Improved apple latent spherical virus-induced gene silencing in multiple soybean genotypes through direct inoculation of agro-infiltrated Nicotiana benthamiana extract. PLANT METHODS 2018. [PMID: 29527233 PMCID: PMC5838930 DOI: 10.1186/s13007-018-0286-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
BACKGROUND Virus induced gene silencing (VIGS) is a powerful genomics tool for interrogating the function of plant genes. Unfortunately, VIGS vectors often produce disease symptoms that interfere with the silencing phenotypes of target genes, or are frequently ineffective in certain plant genotypes or tissue types. This is especially true in crop plants like soybean [Glycine max (L.) Merr]. To address these shortcomings, we modified the inoculation procedure of a VIGS vector based on Apple latent spherical virus (ALSV). The efficacy of this new procedure was assessed in 19 soybean genotypes using a soybean Phytoene desaturase (GmPDS1) gene as the VIGS target. Silencing of GmPDS1 was easily scored as photo-bleached leaves and/or stems. RESULTS In this report, the ALSV VIGS vector was modified by mobilizing ALSV cDNAs into a binary vector compatible with Agrobacterium tumefaciens-mediated delivery, so that VIGS-triggering ALSV variants could be propagated in agro-infiltrated Nicotiana benthamiana leaves. Homogenate of these N. benthamiana leaves was then applied directly onto the unifoliate of young soybean seedlings to initiate systemic gene silencing. This rapid inoculation method bypassed the need for a particle bombardment apparatus. Among the 19 soybean genotypes evaluated with this new method, photo-bleaching indicative of GmPDS1 silencing was observed in nine, with two exhibiting photo-bleaching in 100% of the inoculated individuals. ALSV RNA was detected in pods, embryos, stems, leaves, and roots in symptomatic plants of four genotypes. CONCLUSIONS This modified protocol allowed for inoculation of soybean plants via simple mechanical rubbing with the homogenate of N. benthamiana leaves agro-infiltrated with ALSV VIGS constructs. More importantly, inoculated plants showed no apparent virus disease symptoms which could otherwise interfere with VIGS phenotypes. This streamlined procedure expanded this functional genomics tool to nine soybean genotypes.
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Lu H, Wei K, Ma W, Xie K, Wu J, Lei Y, Dai Y. Effect of acetic acid on the leaching behavior of impurities in metallurgical grade silicon. SEP SCI TECHNOL 2017. [DOI: 10.1080/01496395.2017.1282964] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Fu Q, Xie K, McKenzie TG, Qiao GG. Trithiocarbonates as intrinsic photoredox catalysts and RAFT agents for oxygen tolerant controlled radical polymerization. Polym Chem 2017. [DOI: 10.1039/c6py01994c] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In this study, we reported on the discovery that trithiocarbonates (RAFT agents) can act as intrinsic photocatalyst to significantly reduce the oxygen level in a controlled radical polymerization under visible light irridation.
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Xie K, Colgan LA, Dao MT, Muntean BS, Sutton LP, Orlandi C, Boye SL, Boye SE, Shih CC, Li Y, Xu B, Smith RG, Yasuda R, Martemyanov KA. NF1 Is a Direct G Protein Effector Essential for Opioid Signaling to Ras in the Striatum. Curr Biol 2016; 26:2992-3003. [PMID: 27773571 DOI: 10.1016/j.cub.2016.09.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 08/24/2016] [Accepted: 09/07/2016] [Indexed: 01/19/2023]
Abstract
It is well recognized that G-protein-coupled receptors (GPCRs) can activate Ras-regulated kinase pathways to produce lasting changes in neuronal function. Mechanisms by which GPCRs transduce these signals and their relevance to brain disorders are not well understood. Here, we identify a major Ras regulator, neurofibromin 1 (NF1), as a direct effector of GPCR signaling via Gβγ subunits in the striatum. We find that binding of Gβγ to NF1 inhibits its ability to inactivate Ras. Deletion of NF1 in striatal neurons prevents the opioid-receptor-induced activation of Ras and eliminates its coupling to Akt-mTOR-signaling pathway. By acting in the striatal medium spiny neurons of the direct pathway, NF1 regulates opioid-induced changes in Ras activity, thereby sensitizing mice to psychomotor and rewarding effects of morphine. These results delineate a novel mechanism of GPCR signaling to Ras pathways and establish a critical role of NF1 in opioid addiction.
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Bian Y, Qin C, Xie K, Yu Y, Yu Y. Abstract PR087. Anesth Analg 2016. [DOI: 10.1213/01.ane.0000492493.42566.1e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Sutton LP, Ostrovskaya O, Dao M, Xie K, Orlandi C, Smith R, Wee S, Martemyanov KA. Regulator of G-Protein Signaling 7 Regulates Reward Behavior by Controlling Opioid Signaling in the Striatum. Biol Psychiatry 2016; 80:235-45. [PMID: 26364547 PMCID: PMC4753143 DOI: 10.1016/j.biopsych.2015.07.026] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 07/02/2015] [Accepted: 07/27/2015] [Indexed: 12/11/2022]
Abstract
BACKGROUND Morphine mediates its euphoric and analgesic effects by acting on the μ-opioid receptor (MOR). MOR belongs to the family of G-protein coupled receptors whose signaling efficiency is controlled by the regulator of G-protein signaling (RGS) proteins. Our understanding of the molecular diversity of RGS proteins that control MOR signaling, their circuit specific actions, and underlying cellular mechanisms is very limited. METHODS We used genetic approaches to ablate regulator of G-protein signaling 7 (RGS7) both globally and in specific neuronal populations. We used conditioned place preference and self-administration paradigms to examine reward-related behavior and a battery of tests to assess analgesia, tolerance, and physical dependence to morphine. Electrophysiology approaches were applied to investigate the impact of RGS7 on morphine-induced alterations in neuronal excitability and plasticity of glutamatergic synapses. At least three animals were used for each assessment. RESULTS Elimination of RGS7 enhanced reward, increased analgesia, delayed tolerance, and heightened withdrawal in response to morphine administration. RGS7 in striatal neurons was selectively responsible for determining the sensitivity of rewarding and reinforcing behaviors to morphine without affecting analgesia, tolerance, and withdrawal. In contrast, deletion of RGS7 in dopaminergic neurons did not influence morphine reward. RGS7 exerted its effects by controlling morphine-induced changes in excitability of medium spiny neurons in nucleus accumbens and gating the compositional plasticity of α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid and N-methyl-D-aspartate receptors. CONCLUSIONS This study identifies RGS7 as a novel regulator of MOR signaling by dissecting its circuit specific actions and pinpointing its role in regulating morphine reward by controlling the activity of nucleus accumbens neurons.
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Cui J, Xia T, Xie D, Gao Y, Jia Z, Wei D, Wang L, Huang S, Quan M, Xie K. HGF/Met and FOXM1 form a positive feedback loop and render pancreatic cancer cells resistance to Met inhibition and aggressive phenotypes. Oncogene 2016; 35:4708-18. [PMID: 26876216 PMCID: PMC4985506 DOI: 10.1038/onc.2016.14] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 11/30/2015] [Accepted: 12/27/2015] [Indexed: 02/06/2023]
Abstract
Purpose Hepatocyte growth factor (HGF)/Met signaling plays critical roles in pancreatic ductal adenocarcinoma (PDA) development and progression and is considered a potential therapeutic target for this disease. However, the mechanism of aberrant activation of HGF/Met signaling and resistance to Met inhibition in PDA remains unclear. Experimental Design The mechanistic role of cross-talk between Forkhead box M1 (FOXM1) and HGF/Met signaling in promotion of PDA growth and resistance to Met inhibition was examined using cell culture, molecular biology and mouse models; and the relevance of our experimental and mechanistic findings were validated using human PDA tissues. Results Met was markedly overexpressed in both PDA cell lines and pancreatic tumor specimens, and the expression of Met correlated directly with that of FOXM1 in human tumor specimens. Mechanistically, FOXM1 bound to the promoter region of the Met gene and transcriptionally increased the expression of Met. Increased expression of FOXM1 enhanced the activation of HGF/Met signaling and its downstream pathways, including RAS/extracellular signal-regulated kinase 1/2, phosphoinositide 3-kinase/AKT, and signal transducer and activator of transcription 3. Furthermore, activation of HGF/Met signaling increased the expression and transcriptional activity of FOXM1, and the cross-talk between FOXM1 and HGF/Met signaling promoted PDA growth and resistance to Met inhibition. Conclusions Collectively, our findings identified a positive feedback loop formed by FOXM1 and HGF/Met and revealed that this loop is a potentially effective therapeutic target for PDA.
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Fu Q, Xie K, Tan S, Ren JM, Zhao Q, Webley PA, Qiao GG. The use of reduced copper metal–organic frameworks to facilitate CuAAC click chemistry. Chem Commun (Camb) 2016; 52:12226-12229. [DOI: 10.1039/c6cc06890a] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A reduced copper metal–organic framework (rCu-MOF) containing CuI ions was prepared and employed as a catalyst for ‘Click’ reactions. The rCu-MOF presents higher catalytic activity, good structural stability as well as facile recyclability compared to traditional copper halide catalysts.
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Masuho I, Ostrovskaya O, Kramer GM, Jones CD, Xie K, Martemyanov KA. Distinct profiles of functional discrimination among G proteins determine the actions of G protein-coupled receptors. Sci Signal 2015; 8:ra123. [PMID: 26628681 DOI: 10.1126/scisignal.aab4068] [Citation(s) in RCA: 170] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Members of the heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptor (GPCR) family play key roles in many physiological functions and are extensively exploited pharmacologically to treat diseases. Many of the diverse effects of individual GPCRs on cellular physiology are transduced by heterotrimeric G proteins, which are composed of α, β, and γ subunits. GPCRs interact with and stimulate the binding of guanosine triphosphate (GTP) to the α subunit to initiate signaling. Mammalian genomes encode 16 different G protein α subunits, each one of which has distinct properties. We developed a single-platform, optical strategy to monitor G protein activation in live cells. With this system, we profiled the coupling ability of individual GPCRs for different α subunits, simultaneously quantifying the magnitude of the signal and the rates at which the receptors activated the G proteins. We found that individual receptors engaged multiple G proteins with varying efficacy and kinetics, generating fingerprint-like profiles. Different classes of GPCR ligands, including full and partial agonists, allosteric modulators, and antagonists, distinctly affected these fingerprints to functionally bias GPCR signaling. Finally, we showed that intracellular signaling modulators further altered the G protein-coupling profiles of GPCRs, which suggests that their differential abundance may alter signaling outcomes in a cell-specific manner. These observations suggest that the diversity of the effects of GPCRs on cellular physiology may be determined by their differential engagement of multiple G proteins, coupling to which produces signals with varying signal magnitudes and activation kinetics, properties that may be exploited pharmacologically.
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Xie K, Masuho I, Shih CC, Cao Y, Sasaki K, Lai CWJ, Han PL, Ueda H, Dessauer CW, Ehrlich ME, Xu B, Willardson BM, Martemyanov KA. Stable G protein-effector complexes in striatal neurons: mechanism of assembly and role in neurotransmitter signaling. eLife 2015; 4. [PMID: 26613416 PMCID: PMC4728126 DOI: 10.7554/elife.10451] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Accepted: 11/26/2015] [Indexed: 12/23/2022] Open
Abstract
In the striatum, signaling via G protein-coupled neurotransmitter receptors is essential for motor control. Critical to this process is the effector enzyme adenylyl cyclase type 5 (AC5) that produces second messenger cAMP upon receptor-mediated activation by G protein Golf. However, the molecular organization of the Golf-AC5 signaling axis is not well understood. In this study, we report that in the striatum AC5 exists in a stable pre-coupled complex with subunits of Golf heterotrimer. We use genetic mouse models with disruption in individual components of the complex to reveal hierarchical order of interactions required for AC5-Golf stability. We further identify that the assembly of AC5-Golf complex is mediated by PhLP1 chaperone that plays central role in neurotransmitter receptor coupling to cAMP production motor learning. These findings provide evidence for the existence of stable G protein-effector signaling complexes and identify a new component essential for their assembly.
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Qiao J, Yang HB, Peng YL, Meng QL, Chen C, Ma Y, Xie K, Liu TL, Cai XP, Chen CF. Effect of ORF119 gene deletion on the replication and virulence of orf virus. Acta Virol 2015; 59:257-64. [PMID: 26435149 DOI: 10.4149/av_2015_03_257] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Orf is a severe infectious disease of sheep and goats caused by orf virus (ORFV). To investigate the role of ORF119 gene of ORFV, we constructed ORFV with deleted ORF119 gene and LacZ as reporter gene (ORFV-Δ119-LacZ) via homologous recombination. The results showed that wild-type ORF-SHZ1 and ORFV-Δ119-LacZ deletion viruses replicated in Vero cells to similar titers. Relative transcriptional levels of virulence genes OVIFNR, GIF, VEGF and VIL-10 of ORFV-Δ119-LacZ deletion virus were slightly but not significantly lower after 24 hr compared with the wtORF-SHZ1 virus. In vivo experiments showed that 2-month-old lambs inoculated with ORFV-Δ119-LacZ deletion virus exhibited a similar total clinical score compared with those inoculated with wtORF-SHZ1 virus. Based on these results, we conclude that deletion of the ORF119 gene has no significant effect on ORFV replication and virulence.
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Orlandi C, Xie K, Masuho I, Fajardo-Serrano A, Lujan R, Martemyanov KA. Orphan Receptor GPR158 Is an Allosteric Modulator of RGS7 Catalytic Activity with an Essential Role in Dictating Its Expression and Localization in the Brain. J Biol Chem 2015; 290:13622-39. [PMID: 25792749 DOI: 10.1074/jbc.m115.645374] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Indexed: 11/06/2022] Open
Abstract
Regulators of G protein signaling control the duration and extent of signaling via G protein-coupled receptor (GPCR) pathways by accelerating the GTP hydrolysis on G protein α subunits thereby promoting termination of GPCR signaling. A member of this family, RGS7, plays a critical role in the nervous system where it regulates multiple neurotransmitter GPCRs that mediate vision, memory, and the action of addictive drugs. Previous studies have established that in vivo RGS7 forms mutually exclusive complexes with the membrane protein RGS7-binding protein or the orphan receptor GPR158. In this study, we examine the impact of GPR158 on RGS7 in the brain. We report that knock-out of GPR158 in mice results in marked post-transcriptional destabilization of RGS7 and substantial loss of its association with membranes in several brain regions. We further identified the RGS7-binding site in the C terminus of GPR158 and found that it shares significant homology with the RGS7-binding protein. The proximal portion of the GPR158 C terminus additionally contained a conserved sequence that was capable of enhancing RGS7 GTPase-activating protein activity in solution by an allosteric mechanism acting in conjunction with the regulators of the G protein signaling-binding domain. The distal portion of the GPR158 C terminus contained several phosphodiesterase E γ-like motifs and selectively recruited G proteins in their activated state. The results of this study establish GPR158 as an essential regulator of RGS7 in the native nervous system with a critical role in controlling its expression, membrane localization, and catalytic activity.
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Meng L, Qu J, Guo Q, Xie K, Zhang P, Han L, Zhang G, Qi T. Recovery of Ni, Co, Mn, and Mg from nickel laterite ores using alkaline oxidation and hydrochloric acid leaching. Sep Purif Technol 2015. [DOI: 10.1016/j.seppur.2015.01.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Yu X, Sheng J, Zhao L, Diao Y, Zheng X, Xie K, Zhou M, Hu Z. In vitro plant regeneration of lotus (Nelumbo nucifera). Open Life Sci 2015. [DOI: 10.1515/biol-2015-0016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
AbstractIn this study, an efficient and reproducible plant regeneration system for lotus (Nelumbo nucifera Gaertn.) was established using shoot apical meristems from the buds and one-week-old aseptically germinated embryos as explants. Multiple shoot clumps were induced on Murashige and Skoog (MS) basal medium supplemented with various combinations of N6-Benzylaminopurine (6-BA) and α-Naphthalene acetic acid (NAA). The maximum response was obtained with 2.22 μM 6-BA, and produced 21.33 shoots per explant after four weeks. After five subcultures, multiple shoot clumps were transferred to MS basal medium supplemented with various combinations of 3-Indolebutyric acid (IBA), NAA and sucrose for root induction. After four weeks, plantlets with well-developed roots were achieved on MS basal medium supplemented with 0.54 μM NAA and 30 g/L sucrose with 100% rooting rate. The successfully acclimated plantlets were transferred to pots with the addition of 2 g/L KMnO4 into the soils, and finally fertile plants with much bigger leaves were obtained in the greenhouse. The survival rate was 97.33%.
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Xie K, Fu Q, He Y, Kim J, Goh SJ, Nam E, Qiao GG, Webley PA. Synthesis of well dispersed polymer grafted metal–organic framework nanoparticles. Chem Commun (Camb) 2015; 51:15566-9. [DOI: 10.1039/c5cc06694h] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We prepared novel polymer grafted MOF nanoparticles for the first time with excellent water dispersity and significantly enhanced catalytic effect.
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He Z, Meng Q, Qiao J, Peng Y, Xie K, Liu Y, Cai X, Zhang J, Chen C. Mixed Nipple Infections Caused by Variant of BPV3 and a Putative New Subtype of BPV in Cattle. Transbound Emerg Dis 2014; 63:e140-3. [PMID: 24894388 DOI: 10.1111/tbed.12238] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Indexed: 11/30/2022]
Abstract
Bovine papilloma is a chronic and proliferative skin and mucosal wart caused by Bovine papillomavirus (BPV). In June, 2013, a leaf-and flat-shaped wart disease was observed on the nipple skins in a cattle farm in Xinjiang. To diagnose the disease, we collected the diseased skins for pathological biopsy and DNA analysis by PCR amplification using a pair of degenerate primers FAP59 and FAP64. Sequencing and phylogenetic analysis showed that the infection was caused by a variant of BPV3 and putatively a new subtype of BPV (BPV/CHI-SW1, belonging to the Xi papillomavirus genus). This is the first report of mixed infection caused by variant of BPV3 and BPV (putatively new subtype) in China, and would be of importance for the molecular epidemiological study of the disease.
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Li D, Wei X, Xie K, Chen K, Li J, Fang J. A novel decoy receptor fusion protein for FGF-2 potently inhibits tumour growth. Br J Cancer 2014; 111:68-77. [PMID: 24874473 PMCID: PMC4090743 DOI: 10.1038/bjc.2014.282] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 04/29/2014] [Accepted: 04/30/2014] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Antiangiogenic therapies have been proven effective in cancer treatment. Fibroblast growth factor-2 (FGF-2) has been functionally implicated in tumour angiogenesis and is an important target of antiangiogenic therapies. The aim of this work was to develop a novel FGF-2 inhibitor for cancer therapy. METHODS Eleven fusion proteins were developed by fusing various truncated extracellular regions of FGFR1 with the Fc region of IgG1. The optimal decoy receptor fusion protein with the highest binding affinity for FGF-2 was identified by an FGF-2-binding assay and its potential antitumour effects were investigated. RESULTS We obtained a soluble decoy receptor fusion protein with the highest binding activity for FGF-2, named FGF-Trap. Fibroblast growth factor-Trap significantly abolished FGF-2-stimulated activation of FGF signalling as demonstrated by its suppression of FGF-2-mediated phosphorylation of Erk1/2 and Akt, upregulation of cyclins D1 and E and the increase in mRNA levels of vascular endothelial growth factor R1 and R2 (VEGFR1 and VEGFR2). Furthermore, FGF-Trap effectively suppressed FGF-2-induced proliferation and migration of human umbilical vein endothelial cells (HUVECs) in vitro. Most importantly, FGF-Trap potently inhibited tumour growth and angiogenesis in Caki-1 and A549 xenograft models in vivo. CONCLUSIONS Fibroblast growth factor-Trap potently inhibits tumour growth by blocking FGF-2 signalling pathways and could be an effective therapeutic agent for cancer patients.
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