16 results on '"Jiang, Meisheng"'
Search Results
2. GNAI1 and GNAI3 Reduce Colitis-Associated Tumorigenesis in Mice by Blocking IL6 Signaling and Down-regulating Expression of GNAI2.
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Li, Zhi-Wei, Sun, Beicheng, Gong, Ting, Guo, Sheng, Zhang, Jianhua, Wang, Junlong, Sugawara, Atsushi, Jiang, Meisheng, Yan, Junjun, Gurary, Alexandra, Zheng, Xin, Gao, Bifeng, Xiao, Shu-Yuan, Chen, Wenlian, Ma, Chi, Farrar, Christine, Zhu, Chenjun, Chan, Owen T.M., Xin, Can, and Winnicki, Andrew
- Abstract
Interleukin 6 (IL6) and tumor necrosis factor contribute to the development of colitis-associated cancer (CAC). We investigated these signaling pathways and the involvement of G protein subunit alpha i1 (GNAI1), GNAI2, and GNAI3 in the development of CAC in mice and humans. B6;129 wild-type (control) or mice with disruption of Gnai1 , Gnai2 , and/or Gnai3 or conditional disruption of Gnai2 in CD11c
+ or epithelial cells were given dextran sulfate sodium (DSS) to induce colitis followed by azoxymethane (AOM) to induce carcinogenesis; some mice were given an antibody against IL6. Feces were collected from mice, and the compositions of microbiomes were analyzed by polymerase chain reactions. Dendritic cells (DCs) and myeloid-derived suppressor cells (MDSCs) isolated from spleen and colon tissues were analyzed by flow cytometry. We performed immunoprecipitation and immunoblot analyses of colon tumor tissues, MDSCs, and mouse embryonic fibroblasts to study the expression levels of GNAI1, GNAI2, and GNAI3 and the interactions of GNAI1 and GNAI3 with proteins in the IL6 signaling pathway. We analyzed the expression of Gnai2 messenger RNA by CD11c+ cells in the colonic lamina propria by PrimeFlow, expression of IL6 in DCs by flow cytometry, and secretion of cytokines in sera and colon tissues by enzyme-linked immunosorbent assay. We obtained colon tumor and matched nontumor tissues from 83 patients with colorectal cancer having surgery in China and 35 patients with CAC in the United States. Mouse and human colon tissues were analyzed by histology, immunoblot, immunohistochemistry, and/or RNA-sequencing analyses. GNAI1 and GNAI3 (GNAI1;3) double-knockout (DKO) mice developed more severe colitis after administration of DSS and significantly more colonic tumors than control mice after administration of AOM plus DSS. Development of increased tumors in DKO mice was not associated with changes in fecal microbiomes but was associated with activation of nuclear factor (NF) κB and signal transducer and activator of transcription (STAT) 3; increased levels of GNAI2, nitric oxide synthase 2, and IL6; increased numbers of CD4+ DCs and MDSCs; and decreased numbers of CD8+ DCs. IL6 was mainly produced by CD4+ /CD11b+ , but not CD8+ , DCs in DKO mice. Injection of DKO mice with a blocking antibody against IL6 reduced the expansion of MDSCs and the number of tumors that developed after CAC induction. Incubation of MDSCs or mouse embryonic fibroblasts with IL6 induced activation of either NF-κB by a JAK2-TRAF6-TAK1-CHUK/IKKB signaling pathway or STAT3 by JAK2. This activation resulted in expression of GNAI2, IL6 signal transducer (IL6ST, also called GP130) and nitric oxide synthase 2, and expansion of MDSCs; the expression levels of these proteins and expansion of MDSCs were further increased by the absence of GNAI1;3 in cells and mice. Conditional disruption of Gnai2 in CD11c+ cells of DKO mice prevented activation of NF-κB and STAT3 and changes in numbers of DCs and MDSCs. Colon tumor tissues from patients with CAC had reduced levels of GNAI1 and GNAI3 and increased levels of GNAI2 compared with normal tissues. Further analysis of a public human colorectal tumor DNA microarray database (GSE39582) showed that low Gani1 and Gnai3 messenger RNA expression and high Gnai2 messenger RNA expression were significantly associated with decreased relapse-free survival. GNAI1;3 suppresses DSS-plus-AOM–induced colon tumor development in mice, whereas expression of GNAI2 in CD11c+ cells and IL6 in CD4+ /CD11b+ DCs appears to promote these effects. Strategies to induce GNAI1;3, or block GNAI2 and IL6, might be developed for the prevention or therapy of CAC in patients. [ABSTRACT FROM AUTHOR]- Published
- 2019
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3. Insights into pathogenesis of five novel GCK mutations identified in Chinese MODY patients.
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Liu, Limei, Liu, Yanjun, Ge, Xiaoxu, Liu, Xipeng, Chen, Chen, Wang, Yanzhong, Li, Ming, Yin, Jun, Zhang, Juan, Chen, Yating, Zhang, Rong, Jiang, Yanyan, Zhao, Weijing, Yang, Di, Zheng, Taishan, Lu, Ming, Zhuang, Langen, and Jiang, Meisheng
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TYPE 2 diabetes ,GLUCOKINASE ,GENETIC mutation ,INSULIN resistance ,PROTEIN stability ,HYPERGLYCEMIA - Abstract
Abstract Objective Heterozygous inactivating mutations in GCK are associated with defects in pancreatic insulin secretion and/or hepatic glycogen synthesis leading to mild chronic hyperglycaemia of maturity onset diabetes of young type 2 (MODY2). However, the effect of naturally occurring GCK mutations on the pathogenesis for MODY2 hyperglycaemia remains largely unclear, especially in the Asian population. The aim of this study is to explore the potential pathogenicity of novel GCK mutations related to MODY2. Methods Genetic screening for GCK mutations from 96 classical MODY families was performed, and structure-function characterization and clinical profile of identified GCK mutations were conducted. Results Five novel (F195S, I211T, V222D, E236G and K458R) and five known (T49N, I159V, R186X, A188T and M381T) mutations were identified and co-segregated with hyperglycaemia in their pedigrees. R186X generates non-functional truncated form and V222D and E236G fully inactivate glucokinase due to severe structure disruptions. The other seven GCK mutations exhibited marked reductions in catalytic efficiency and thermo-stability; notably, the interaction with GKRP was significantly enhanced in I211T, I159V, T49N and K458R, reduced in F195S and M381T, and completely lost with A188T. 31% (17/55) of MODY2 patients showed signs of insulin resistance. Conventional hypoglycaemia treatment did not improve the HbA1C in MODY2 patients when insulin resistance is not present. Conclusions Five novel GCK mutations have been identified in Chinese MODY. The defects in enzymatic activity and protein stability, together with alteration of GKRP binding on GCK mutants may synergistically contribute to the development of MODY2 hyperglycaemia. No treatment should be prescribed to MODY2 patients when insulin resistance is not present. Highlights • Five novel and five known mutations were identified in MODY pedigrees. • MODY2 accounts for 10.4% of classical MODY cases in Chinese in this study. • Defects in enzymatic activity, stability and GKRP interaction may co-induce MODY2. • 31% of MODY2 patients showed signs of insulin resistance. • No treatment should be prescribed to MODY2 patients without insulin resistance. [ABSTRACT FROM AUTHOR]
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- 2018
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4. 2-Hydroxyglutarate Inhibits ATP Synthase and mTOR Signaling.
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Fu, Xudong, Chin, Randall M., Vergnes, Laurent, Hwang, Heejun, Deng, Gang, Xing, Yanpeng, Pai, Melody Y., Li, Sichen, Ta, Lisa, Fazlollahi, Farbod, Chen, Chuo, Prins, Robert M., Teitell, Michael A., Nathanson, David A., Lai, Albert, Faull, Kym F., Jiang, Meisheng, Clarke, Steven G., Cloughesy, Timothy F., and Graeber, Thomas G.
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Summary We discovered recently that the central metabolite α-ketoglutarate (α-KG) extends the lifespan of C. elegans through inhibition of ATP synthase and TOR signaling. Here we find, unexpectedly, that ( R )-2-hydroxyglutarate (( R )-2HG), an oncometabolite that interferes with various α-KG-mediated processes, similarly extends worm lifespan. ( R )-2HG accumulates in human cancers carrying neomorphic mutations in the isocitrate dehydrogenase (IDH) 1 and 2 genes. We show that, like α-KG, both ( R )-2HG and ( S )-2HG bind and inhibit ATP synthase and inhibit mTOR signaling. These effects are mirrored in IDH1 mutant cells, suggesting a growth-suppressive function of ( R )-2HG. Consistently, inhibition of ATP synthase by 2-HG or α-KG in glioblastoma cells is sufficient for growth arrest and tumor cell killing under conditions of glucose limitation, e.g., when ketone bodies (instead of glucose) are supplied for energy. These findings inform therapeutic strategies and open avenues for investigating the roles of 2-HG and metabolites in biology and disease. [ABSTRACT FROM AUTHOR]
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- 2015
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5. A human opsin-related gene that encodes a retinaldehyde-binding protein.
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Shen, Daiweis and Jiang, Meisheng
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- 1994
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6. Expression of murine ELL-associated factor 2 (<TOGGLE>Eaf2</TOGGLE>) is developmentally regulated
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Li, Min, Wu, Xiangbing, Zhuang, Fengfeng, Jiang, Shaoyun, Jiang, Meisheng, and Liu, Yi-Hsin
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Eaf2, ELL-associated factor 2, encodes a protein that is homologous to the human EAF1, which was shown to interact with the transcriptional elongation factor MEN/ELL. During mouse embryogenesis, Eaf2 is preferentially expressed in the central nervous system and in sensory and neuroendocrine organs, including the brain, spinal cord, cranial and spinal ganglia, developing otocyst, the retina, and the pituitary. Eaf2 transcripts were also found in sites where active epitheliummesenchymal interactions are occurring. These included the invaginating tooth buds, mammary gland anlage, submandibular glands, the lung, the pancreas, and the kidney. Other sites of expression included bladder and intestine. In the developing lens, Eaf2 transcripts were absent in the proliferating anterior lens epithelial cells but were present in the terminally differentiated primary lens fiber cells and also in nonproliferating lens fiber cells in the equatorial zone where lens epithelial cells withdraw from cell cycle and terminally differentiate into secondary lens fiber cells. This spatially restricted pattern of Eaf2 expression in the developing lens suggests that Eaf2 may play an important role in regulating lens maturation. Developmental Dynamics 228:273280, 2003. © 2003 Wiley-Liss, Inc.
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- 2003
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7. β-Galactosidase transgene expression in transplanted rabbit retinal pigment epithelial cells in vivo
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Osusky, R., Jiang, Meisheng, Spee, Christine, Büchi, Ernst R., Ye, Junjie, and Ryan, Stephen J.
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• Background: Intraocular transplantation of genetically modified cells that release a particular substance could have a major impact on the treatment of various ocular diseases. We studied the expression of the reporter gene ß-galactosidase (lacZ) in transplanted retinal pigment epithelial (RPE) cells in vivo • Methods: RPE cells from pigmented rabbits were transduced with the ß-galactosidase gene in a retroviral vector. Cells were then assayed for gene expression and transplanted subretinally into the eyes of New Zealand White rabbits. RPE cells that were transduced with a similar vector without the ß-galactosidase gene were used as controls. Rabbits were killed on days 1, 7, and 21 and the eyes processed for transmission electron microscopy • Results: Neomycin-resistant rabbit RPE cells that showed ß-galactosidase activity were generated within 2–5 weeks. After transplantation, viable RPE cells that expressed the transgene and that phagocytosed rod outer segments were observed on days 1, 7, and 21 • Conclusions: The results show that generation of genetically modified RPE cells is feasible and that the transplanted cells remain viable and continue to express the transgene in the subretinal space of the host animal for at least 21 days. Transplantation of such genetically modified RPE cells could provide a new tool for studying retinal diseases and, potentially, for correcting metabolic abnormalities in retinal degenerations and dystrophies.
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- 1995
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8. Cytoplasmic Retinal Localization of an Evolutionary Homolog of the Visual Pigments
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Pandey, Sujay, Blanks, Janet C., Spee, Christine, Jiang, Meisheng, and Fong, Henry K.W.
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A rhodopsin-related protein is preferentially expressed at high levels in retinal pigment epithelium (RPE) and in Müller cells. The putative RPE-retinal G protein-coupled receptor (RGR) was localized in light-adapted bovine retina by means of electron microscopic immunocytochemistry. In the RPE, the protein was localized to a widespread intracellular compartment. Except for the region adjacent to the basal surface, the RPE cytoplasm was labeled throughout the cell including the apical surface. In Müller cells also RGR was found in the intracellular compartment, especially in the cytoplasm in the region of the Müller cell endfeet and proximal cell processes. Subcellular fractionalion studies of bovine RPE and neural retina indicated that RGR is a membrane-bound protein. The intracellular localization of RGR is a unique variation in the subcellular distribution of seven-transmembrane-domain receptors and suggests an unconventional role for RGR in the signal transduction process.
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- 1994
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9. Cloning and Expression of a Novel Mammalian Homolog ofDrosophila Transient Receptor Potential(Trp) Involved in Calcium Entry Secondary to Activation of Receptors Coupled by the GqClass of G Protein*
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Boulay, Guylain, Zhu, Xi, Peyton, Mike, Jiang, Meisheng, Hurst, Raymond, Stefani, Enrico, and Birnbaumer, Lutz
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Hormonal stimulation of Gq-protein coupled receptors triggers Ca2+mobilization from internal stores. This is followed by a Ca2+entry through the plasma membrane.DrosophilaTrp and Trpl proteins have been implicated in Ca2+entry and three mammalian homologues ofDrosophilaTrp/Trpl, hTrp1, hTrp3 and bTrp4 (also bCCE) have been cloned and expressed. Using mouse brain RNA as template, we report here the polymerase chain reaction-based cloning and functional expression of a novel Trp, mTrp6. The cDNA encodes a protein of 930 amino acids, the sequence of which is 36.8, 36.3, 43.1, 38.6, and 74.1% identical to DrosophilaTrp and Trpl, bovine Trp4, and human Trp1 and Trp3, respectively. Transient expression of mTrp6 in COS.M6 cells by transfection of the full-length mTrp6 cDNA increases Ca2+entry induced by stimulation of co-transfected M5 muscarinic acetylcholine receptor with carbachol (CCh), as seen by dual wavelength fura 2 fluorescence ratio measurements. The mTrp6-mediated increase in Ca2+entry activity was blocked by SKF-96365 and La3+. Ca2+entry activity induced by thapsigargin was similar in COS cells transfected with or without the mTrp6 cDNA. The thapsigargin-stimulated Ca2+entry could not be further stimulated by CCh in control cells but was markedly increased in mTrp6-transfected cells. Records of whole cell transmembrane currents developed in response to voltage ramps from −80 to +40 mV in control HEK cells and HEK cells stably expressing mTrp6 revealed the presence of a muscarinic receptor responsive non-selective cation conductance in Trp6 cells that was absent in control cells. Our data support the hypothesis that mTrp6 encodes an ion channel subunit that mediates Ca2+entry stimulated by a G-protein coupled receptor, but not Ca2+entry stimulated by intracellular Ca2+store depletion.
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- 1997
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10. Receptor-activated Ca2+Influx via Human Trp3 Stably Expressed in Human Embryonic Kidney (HEK)293 Cells
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Zhu, Xi, Jiang, Meisheng, and Birnbaumer, Lutz
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Ca2+release from its internal stores as a result of activation of phospholipase C is accompanied by Ca2+influx from the extracellular space. Ca2+influx channels may be formed of proteins homologous toDrosophilaTrp. At least six non-allelic Trpgenes are present in the mouse genome. Full-length human, bovine, mouse, and rat cDNAs for Trp1, 3, 4, 6 have been cloned. Expression of these genes in various mammalian cells has provided evidence that Trp proteins form plasma membrane Ca2+-permeant channels that can be activated by an agonist that activates phospholipase C, by inositol 1,4,5-trisphosphate, and/or store depletion. We have stably expressed human Trp3 (hTrp3) in human embryonic kidney (HEK)293 cells. Measurement of intracellular Ca2+concentrations in Fura2-loaded cells showed that cell lines expressing hTrp3 have significantly higher basal and agonist-stimulated influxes of Ca2+, Mn2+, Ba2+, and Sr2+than control cells. The increase in Ca2+entry attributable to the expression of hTrp3 obtained upon store depletion by thapsigargin was much lower than that obtained by stimulation with agonists acting via a Gq-coupled receptor. Addition of agonists to thapsigargin-treated Trp3 cells resulted in a further increase in the entry of divalent cations. The increased cation entry in Trp3 cells was blocked by high concentrations of SKF 96365, verapamil, La3+, Ni2+, and Gd3+. The Trp3-mediated Ca2+influx activated by agonists was inhibited by a phospholipase C inhibitor, U73122. We propose that expression of hTrp3 in these cells forms a non-selective cation channel that opens after the activation of phospholipase C but not after store depletion. In addition, a subpopulation of the expressed hTrp3 may form heteromultimeric channels with endogenous proteins that are sensitive to store depletion.
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- 1998
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11. Purification of BAC DNA for High-Efficiency Transgenesis
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Gangalum, Rajendra K, Jing, Zhe, Nagaoka, Yoshiko, Jiang, Meisheng, and Bhat, Suraj P.
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An unresolved bottleneck in bacterial artificial chromosome (BAC) transgenesis is low efficiency generation of founder mice because of suboptimal quality of the manipulated BAC DNA. Using mini-gel electrophoresis and electro-elution that circumvents CsCl2centrifugation, column chromatography, and resin purifications, we have used RECOCHIP, a commercially available dialysis cassette for the purification of BAC DNA that generates transgenic founders with up to 80% efficiency.
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- 2011
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12. Localization of the human RGR opsin gene to chromosome 10q23
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Chen, Xiao-Ning, Korenberg, Julie R., Jiang, Meisheng, Shen, Daiwei, and Fong, H. K. W.
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Abstract: The human RGR gene encodes an opsin protein (retinal G protein-coupled receptor), which is expressed in Müller cells and the retinal pigment epithelium and is thought to play a role in the visual process. To investigate a possible linkage of the RGR gene to retinal dystrophies, the locus of the gene was mapped on human metaphase chromosomes. Genomic and cDNA fragments of the human RGR gene were used as probes for fluorescence in situ hybridization. Analysis of the fluorescence signals on high-resolution banded chromosomes showed that the RGR gene is localized to human chromosome 10q23. This result now provides for the rapid analysis of this gene with respect to inherited diseases of the retina.
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- 1996
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13. Stimulation of Hair Growth by Small Molecules that Activate Autophagy
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Chai, Min, Jiang, Meisheng, Vergnes, Laurent, Fu, Xudong, de Barros, Stéphanie C., Doan, Ngan B., Huang, Wilson, Chu, Jessie, Jiao, Jing, Herschman, Harvey, Crooks, Gay M., Reue, Karen, and Huang, Jing
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Hair plays important roles, ranging from the conservation of body heat to the preservation of psychological well-being. Hair loss or alopecia affects millions worldwide, but methods that can be used to regrow hair are lacking. We report that quiescent (telogen) hair follicles can be stimulated to initiate anagen and hair growth by small molecules that activate autophagy, including the metabolites α-ketoglutarate (α-KG) and α-ketobutyrate (α-KB), and the prescription drugs rapamycin and metformin, which impinge on mTOR and AMPK signaling. Stimulation of hair growth by these agents is blocked by specific autophagy inhibitors, suggesting a mechanistic link between autophagy and hair regeneration. Consistently, increased autophagy is detected upon anagen entry during the natural hair follicle cycle, and oral α-KB prevents hair loss in aged mice. Our finding that anagen can be pharmacologically activated in telogen skin when natural anagen-inducing signal(s) are absent has implications for the treatment of hair loss patients.
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- 2019
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14. A large Rab GTPase encoded by CRACR2Ais a component of subsynaptic vesicles that transmit T cell activation signals
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Srikanth, Sonal, Kim, Kyun-Do, Gao, Yuanyuan, Woo, Jin Seok, Ghosh, Shubhamoy, Calmettes, Guillaume, Paz, Aviv, Abramson, Jeff, Jiang, Meisheng, and Gwack, Yousang
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Recruitment of intracellular vesicles containing the large GTPase CRACR2A to the immunological synapse mediates T cell receptor signaling.
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- 2016
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15. S1666 Identification and Characterization of Novel Rat CRF Receptor Type 1 Isoforms in the Gastrointestinal Tract.
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Wu, Shuping V., Jiang, Meisheng, Mulugeta, Million, Lai, Jiunu J., Yuan, Pu-Qing, and Tache, Yvette
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- 2008
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16. Gαi1and Gαi3Are Required for Epidermal Growth Factor–Mediated Activation of the Akt-mTORC1 Pathway
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Cao, Cong, Huang, Xuesong, Han, Yuyuan, Wan, Yinsheng, Birnbaumer, Lutz, Feng, Geng-Sheng, Marshall, John, Jiang, Meisheng, and Chu, Wen-Ming
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Two members of the Gαifamily of G proteins form complexes with EGFR and the adaptor protein Gab1 to mediate activation of Akt.
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- 2009
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