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Lin Y, Yang F, Dai X, Shan J, Cao H, Hu G, Zhang C, Xing C. Mitochondria-associated endoplasmic reticulum membrane as a mediator of vanadium-induced endoplasmic reticulum quality control in duck brains. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:26510-26526. [PMID: 38446297 DOI: 10.1007/s11356-023-31413-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 12/04/2023] [Indexed: 03/07/2024]
Abstract
Vanadium (V) plays a crucial role in normal cells, but excess V causes multi-organ toxicity, including neurotoxicity. Mitochondria-associated endoplasmic reticulum membrane (MAM) is a dynamic structure between endoplasmic reticulum (ER) and mitochondria that mediates ER quality control (ERQC). To explore the effects of excess V on MAM and ERQC in the brain, 72 ducks were randomly divided into two groups: the control group (basal diet) and the V group (30 mg V/kg basal diet). On days 22 and 44, brain tissues were collected for histomorphological observation and determination of trace element contents. In addition, the mRNA and protein levels of MAM and ERQC-related factors in the brain were analyzed. Results show that excessive V causes the imbalance of trace elements, the integrity disruption of MAM, rupture of ER and autophagosomes formation. Moreover, it inhibits IP3R and VDAC1 co-localization, down-regulates the expression levels of MAM-related factors, but up-regulates the expression levels of ERQC and autophagy related factors. Together, results indicate that V exposure causes disruption of MAM and activates ERQC, which is further causing autophagy.
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Affiliation(s)
- Yiqun Lin
- Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, No. 1101 Zhimin Avenue, Economic and Technological Development District, Nanchang, 330045, Jiangxi, People's Republic of China
| | - Fan Yang
- Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, No. 1101 Zhimin Avenue, Economic and Technological Development District, Nanchang, 330045, Jiangxi, People's Republic of China
| | - Xueyan Dai
- Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, No. 1101 Zhimin Avenue, Economic and Technological Development District, Nanchang, 330045, Jiangxi, People's Republic of China
| | - Jiyi Shan
- Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, No. 1101 Zhimin Avenue, Economic and Technological Development District, Nanchang, 330045, Jiangxi, People's Republic of China
| | - Huabin Cao
- Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, No. 1101 Zhimin Avenue, Economic and Technological Development District, Nanchang, 330045, Jiangxi, People's Republic of China
| | - Guoliang Hu
- Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, No. 1101 Zhimin Avenue, Economic and Technological Development District, Nanchang, 330045, Jiangxi, People's Republic of China
| | - Caiying Zhang
- Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, No. 1101 Zhimin Avenue, Economic and Technological Development District, Nanchang, 330045, Jiangxi, People's Republic of China
| | - Chenghong Xing
- Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, No. 1101 Zhimin Avenue, Economic and Technological Development District, Nanchang, 330045, Jiangxi, People's Republic of China.
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Bangari DS, Lanigan LG, Cramer SD, Grieves JL, Meisner R, Rogers AB, Galbreath EJ, Bolon B. Toxicologic Neuropathology of Novel Biotherapeutics. Toxicol Pathol 2023; 51:414-431. [PMID: 38380881 DOI: 10.1177/01926233241230542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2024]
Abstract
Biotherapeutic modalities such as cell therapies, gene therapies, nucleic acids, and proteins are increasingly investigated as disease-modifying treatments for severe and life-threatening neurodegenerative disorders. Such diverse bio-derived test articles are fraught with unique and often unpredictable biological consequences, while guidance regarding nonclinical experimental design, neuropathology evaluation, and interpretation is often limited. This paper summarizes key messages offered during a half-day continuing education course on toxicologic neuropathology of neuro-targeted biotherapeutics. Topics included fundamental neurobiology concepts, pharmacology, frequent toxicological findings, and their interpretation including adversity decisions. Covered biotherapeutic classes included cell therapies, gene editing and gene therapy vectors, nucleic acids, and proteins. If agents are administered directly into the central nervous system, initial screening using hematoxylin and eosin (H&E)-stained sections of currently recommended neural organs (brain [7 levels], spinal cord [3 levels], and sciatic nerve) may need to expand to include other components (e.g., more brain levels, ganglia, and/or additional nerves) and/or special neurohistological procedures to characterize possible neural effects (e.g., cell type-specific markers for reactive glial cells). Scientists who evaluate the safety of novel biologics will find this paper to be a practical reference for preclinical safety testing and risk assessment.
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Affiliation(s)
| | | | | | | | - René Meisner
- Denali Therapeutics, South San Francisco, California, USA
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3
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Tournier B, Bouteldja F, Amossé Q, Nicolaides A, Duarte Azevedo M, Tenenbaum L, Garibotto V, Ceyzériat K, Millet P. 18 kDa Translocator Protein TSPO Is a Mediator of Astrocyte Reactivity. ACS OMEGA 2023; 8:31225-31236. [PMID: 37663488 PMCID: PMC10468775 DOI: 10.1021/acsomega.3c03368] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 08/01/2023] [Indexed: 09/05/2023]
Abstract
An increase in astrocyte reactivity has been described in Alzheimer's disease and seems to be related to the presence of a pro-inflammatory environment. Reactive astrocytes show an increase in the density of the 18 kDa translocator protein (TSPO), but TSPO involvement in astrocyte functions remains poorly understood. The goal of this study was to better characterize the mechanisms leading to the increase in TSPO under inflammatory conditions and the associated consequences. For this purpose, the C6 astrocytic cell line was used in the presence of lipopolysaccharide (LPS) or TSPO overexpression mediated by the transfection of a plasmid encoding TSPO. The results show that nonlethal doses of LPS induced TSPO expression at mRNA and protein levels through a STAT3-dependent mechanism and increased the number of mitochondria per cell. LPS stimulated reactive oxygen species (ROS) production and decreased glucose consumption (quantified by the [18F]FDG uptake), and these effects were diminished by FEPPA, a TSPO antagonist. The transfection-mediated overexpression of TSPO induced ROS production, and this effect was blocked by FEPPA. In addition, a synergistic effect of overexpression of TSPO and LPS on ROS production was observed. These data show that the increase of TSPO in astrocytic cells is involved in the regulation of glucose metabolism and in the pro-inflammatory response. These data suggest that the overexpression of TSPO by astrocytes in Alzheimer's disease would have rather deleterious effects by promoting the pro-inflammatory response.
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Affiliation(s)
- Benjamin
B. Tournier
- Department
of Psychiatry, University Hospitals of Geneva, Geneva 1206, Switzerland
- Department
of Psychiatry, University of Geneva, Geneva 1211, Switzerland
| | - Farha Bouteldja
- Department
of Psychiatry, University of Geneva, Geneva 1211, Switzerland
| | - Quentin Amossé
- Department
of Psychiatry, University of Geneva, Geneva 1211, Switzerland
| | - Alekos Nicolaides
- Department
of Psychiatry, University of Geneva, Geneva 1211, Switzerland
| | - Marcelo Duarte Azevedo
- Laboratory
of Cellular and Molecular Neurotherapies, Center for Neuroscience
Research, Clinical Neuroscience Department, Lausanne University Hospital, Lausanne 1011, Switzerland
| | - Liliane Tenenbaum
- Laboratory
of Cellular and Molecular Neurotherapies, Center for Neuroscience
Research, Clinical Neuroscience Department, Lausanne University Hospital, Lausanne 1011, Switzerland
| | - Valentina Garibotto
- Division
of Nuclear Medicine, Diagnostic Department, University Hospitals of Geneva, Geneva 1206, Switzerland
- CIBM
Center for BioMedical Imaging; NIMTLab, Faculty of Medicine, University of Geneva, Geneva 1211, Switzerland
| | - Kelly Ceyzériat
- Department
of Psychiatry, University Hospitals of Geneva, Geneva 1206, Switzerland
- Department
of Psychiatry, University of Geneva, Geneva 1211, Switzerland
- Division
of Nuclear Medicine, Diagnostic Department, University Hospitals of Geneva, Geneva 1206, Switzerland
- CIBM
Center for BioMedical Imaging; NIMTLab, Faculty of Medicine, University of Geneva, Geneva 1211, Switzerland
| | - Philippe Millet
- Department
of Psychiatry, University Hospitals of Geneva, Geneva 1206, Switzerland
- Department
of Psychiatry, University of Geneva, Geneva 1211, Switzerland
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Small open reading frames in plant research: from prediction to functional characterization. 3 Biotech 2022; 12:76. [PMID: 35251879 PMCID: PMC8873315 DOI: 10.1007/s13205-022-03147-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 02/11/2022] [Indexed: 11/01/2022] Open
Abstract
Gene prediction is a laborious and time-consuming task. The advancement of sequencing technologies and bioinformatics tools, coupled with accelerated rate of ribosome profiling and mass spectrometry development, have made identification of small open reading frames (sORFs) (< 100 codons) in various plant genomes possible. The past 50 years have seen sORFs being isolated from many organisms. However, to date, a comprehensive sORF annotation pipeline is as yet unavailable, hence, addressed in our review. Here, we also provide current information on classification and functions of plant sORFs and their potential applications in crop improvement programs.
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Protein phosphatase 2A holoenzymes regulate leucine-rich repeat kinase 2 phosphorylation and accumulation. Neurobiol Dis 2021; 157:105426. [PMID: 34144124 DOI: 10.1016/j.nbd.2021.105426] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 06/09/2021] [Accepted: 06/10/2021] [Indexed: 11/22/2022] Open
Abstract
LRRK2 is a highly phosphorylated multidomain protein and mutations in the gene encoding LRRK2 are a major genetic determinant of Parkinson's disease (PD). Dephosphorylation at LRRK2's S910/S935/S955/S973 phosphosite cluster is observed in several conditions including in sporadic PD brain, in several disease mutant forms of LRRK2 and after pharmacological LRRK2 kinase inhibition. However, the mechanism of LRRK2 dephosphorylation is poorly understood. We performed a phosphatome-wide reverse genetics screen to identify phosphatases involved in the dephosphorylation of the LRRK2 phosphosite S935. Candidate phosphatases selected from the primary screen were tested in mammalian cells, Xenopus oocytes and in vitro. Effects of PP2A on endogenous LRRK2 phosphorylation were examined via expression modulation with CRISPR/dCas9. Our screening revealed LRRK2 phosphorylation regulators linked to the PP1 and PP2A holoenzyme complexes as well as CDC25 phosphatases. We showed that dephosphorylation induced by different kinase inhibitor triggered relocalisation of phosphatases PP1 and PP2A in LRRK2 subcellular compartments in HEK-293 T cells. We also demonstrated that LRRK2 is an authentic substrate of PP2A both in vitro and in Xenopus oocytes. We singled out the PP2A holoenzyme PPP2CA:PPP2R2 as a powerful phosphoregulator of pS935-LRRK2. Furthermore, we demonstrated that this specific PP2A holoenzyme induces LRRK2 relocalization and triggers LRRK2 ubiquitination, suggesting its involvement in LRRK2 clearance. The identification of the PPP2CA:PPP2R2 complex regulating LRRK2 S910/S935/S955/S973 phosphorylation paves the way for studies refining PD therapeutic strategies that impact LRRK2 phosphorylation.
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Santiago FS, Li Y, Zhong L, Raftery MJ, Lins L, Khachigian LM. Truncated YY1 interacts with BASP1 through a 339KLK341 motif in YY1 and suppresses vascular smooth muscle cell growth and intimal hyperplasia after vascular injury. Cardiovasc Res 2021; 117:2395-2406. [PMID: 33508088 DOI: 10.1093/cvr/cvab021] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 10/27/2020] [Accepted: 01/19/2021] [Indexed: 11/12/2022] Open
Abstract
AIMS In-stent restenosis and late stent thrombosis are complications associated with the use of metallic and drug-coated stents. Strategies that inhibit vascular smooth muscle cell (SMC) proliferation without affecting endothelial cell (EC) growth would be helpful in reducing complications arising from percutaneous interventions. Our group previously showed that the forced expression of the injury-inducible zinc finger (ZNF) transcription factor, yin yang-1 (YY1) comprising 414 residues inhibits neointima formation in carotid arteries of rabbits and rats. YY1 inhibits SMC proliferation without affecting EC growth. Identifying a shorter version of YY1 retaining cell-selective inhibition would make it more amenable for potential use as a gene therapeutic agent. METHODS AND RESULTS We dissected YY1 into a range of shorter fragments (YY1A-D, YY1Δ) and found that the first two ZNFs in YY1 (construct YY1B, spanning 52 residues) repressed SMC proliferation. Receptor Binding Domain analysis predicts a three residue (339KLK341) interaction domain. Mutation of 339KLK341 to 339AAA341 in YY1B (called YY1Bm) abrogated YY1B's ability to inhibit SMC but not EC proliferation and migration. Incubation of recombinant GST-YY1B and GST-YY1Bm with SMC lysates followed by precipitation with glutathione-agarose beads and mass spectrometric analysis identified a novel interaction between YY1B and BASP1. Overexpression of BASP1, like YY1, inhibited SMC but not EC proliferation and migration. BASP1 siRNA partially rescued SMC from growth inhibition by YY1B. In the rat carotid balloon injury model, adenoviral overexpression of YY1B, like full-length YY1, reduced neointima formation, whereas YY1Bm had no such effect. CD31 immunostaining suggested YY1B could increase re-endothelialization in a 339KLK341-dependent manner. CONCLUSIONS These studies identify a truncated form of YY1 (YY1B) that can interact with BASP1 and inhibits SMC proliferation, migration and intimal hyperplasia after balloon injury of rat carotid arteries as effectively as full length YY1. We demonstrate the therapeutic potential of YY1B in vascular proliferative disease.
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Affiliation(s)
- Fernando S Santiago
- Vascular Biology and Translational Research Laboratory, School of Medical Sciences, UNSW Medicine, University of New South Wales, Sydney NSW 2052, Australia
| | - Yue Li
- Vascular Biology and Translational Research Laboratory, School of Medical Sciences, UNSW Medicine, University of New South Wales, Sydney NSW 2052, Australia
| | - Ling Zhong
- Bioanalytical Mass Spectrometry Facility, Mark Wainwright Analytical Centre, University of New South Wales, Sydney NSW 2052, Australia
| | - Mark J Raftery
- Bioanalytical Mass Spectrometry Facility, Mark Wainwright Analytical Centre, University of New South Wales, Sydney NSW 2052, Australia
| | - Laurence Lins
- Molecular Biophysics at Interface Lab, University of Liège-Gembloux Agro Bio Tech, Passage des Déportés, 2-5030 Gembloux-Belgium
| | - Levon M Khachigian
- Vascular Biology and Translational Research Laboratory, School of Medical Sciences, UNSW Medicine, University of New South Wales, Sydney NSW 2052, Australia
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Richetin K, Steullet P, Pachoud M, Perbet R, Parietti E, Maheswaran M, Eddarkaoui S, Bégard S, Pythoud C, Rey M, Caillierez R, Q Do K, Halliez S, Bezzi P, Buée L, Leuba G, Colin M, Toni N, Déglon N. Tau accumulation in astrocytes of the dentate gyrus induces neuronal dysfunction and memory deficits in Alzheimer's disease. Nat Neurosci 2020; 23:1567-1579. [PMID: 33169029 DOI: 10.1038/s41593-020-00728-x] [Citation(s) in RCA: 90] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 09/24/2020] [Indexed: 12/20/2022]
Abstract
Alzheimer's disease (AD) is characterized by the accumulation of the tau protein in neurons, neurodegeneration and memory loss. However, the role of non-neuronal cells in this chain of events remains unclear. In the present study, we found accumulation of tau in hilar astrocytes of the dentate gyrus of individuals with AD. In mice, the overexpression of 3R tau specifically in hilar astrocytes of the dentate gyrus altered mitochondrial dynamics and function. In turn, these changes led to a reduction of adult neurogenesis, parvalbumin-expressing neurons, inhibitory synapses and hilar gamma oscillations, which were accompanied by impaired spatial memory performances. Together, these results indicate that the loss of tau homeostasis in hilar astrocytes of the dentate gyrus is sufficient to induce AD-like symptoms, through the impairment of the neuronal network. These results are important for our understanding of disease mechanisms and underline the crucial role of astrocytes in hippocampal function.
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Affiliation(s)
- Kevin Richetin
- Department of Psychiatry, Center for Psychiatric Neurosciences, Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland. .,Laboratory of Neurotherapies and Neuromodulation, Neuroscience Research Center (CRN), Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland. .,Department of Clinical Neuroscience (DNC), Laboratory of Neurotherapies and Neuromodulation, Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland.
| | - Pascal Steullet
- Department of Psychiatry, Center for Psychiatric Neurosciences, Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland
| | - Mathieu Pachoud
- Laboratory of Neurotherapies and Neuromodulation, Neuroscience Research Center (CRN), Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland.,Department of Clinical Neuroscience (DNC), Laboratory of Neurotherapies and Neuromodulation, Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland
| | - Romain Perbet
- Univ. Lille, Inserm, CHU Lille, U1172 - LilNCog - Lille Neuroscience & Cognition, Lille, France
| | - Enea Parietti
- Department of Psychiatry, Center for Psychiatric Neurosciences, Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland
| | - Mathischan Maheswaran
- Laboratory of Neurotherapies and Neuromodulation, Neuroscience Research Center (CRN), Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland.,Department of Clinical Neuroscience (DNC), Laboratory of Neurotherapies and Neuromodulation, Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland
| | - Sabiha Eddarkaoui
- Univ. Lille, Inserm, CHU Lille, U1172 - LilNCog - Lille Neuroscience & Cognition, Lille, France
| | - Séverine Bégard
- Univ. Lille, Inserm, CHU Lille, U1172 - LilNCog - Lille Neuroscience & Cognition, Lille, France
| | - Catherine Pythoud
- Laboratory of Neurotherapies and Neuromodulation, Neuroscience Research Center (CRN), Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland.,Department of Clinical Neuroscience (DNC), Laboratory of Neurotherapies and Neuromodulation, Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland
| | - Maria Rey
- Laboratory of Neurotherapies and Neuromodulation, Neuroscience Research Center (CRN), Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland.,Department of Clinical Neuroscience (DNC), Laboratory of Neurotherapies and Neuromodulation, Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland
| | - Raphaëlle Caillierez
- Univ. Lille, Inserm, CHU Lille, U1172 - LilNCog - Lille Neuroscience & Cognition, Lille, France
| | - Kim Q Do
- Department of Psychiatry, Center for Psychiatric Neurosciences, Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland
| | - Sophie Halliez
- Univ. Lille, Inserm, CHU Lille, U1172 - LilNCog - Lille Neuroscience & Cognition, Lille, France
| | - Paola Bezzi
- Department of Fundamental Neurosciences, University of Lausanne, Lausanne, Switzerland
| | - Luc Buée
- Univ. Lille, Inserm, CHU Lille, U1172 - LilNCog - Lille Neuroscience & Cognition, Lille, France
| | - Geneviève Leuba
- Department of Psychiatry, Center for Psychiatric Neurosciences, Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland
| | - Morvane Colin
- Univ. Lille, Inserm, CHU Lille, U1172 - LilNCog - Lille Neuroscience & Cognition, Lille, France
| | - Nicolas Toni
- Department of Psychiatry, Center for Psychiatric Neurosciences, Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland.
| | - Nicole Déglon
- Laboratory of Neurotherapies and Neuromodulation, Neuroscience Research Center (CRN), Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland.,Department of Clinical Neuroscience (DNC), Laboratory of Neurotherapies and Neuromodulation, Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland
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8
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Soligo M, Chiaretti A, Leotta E, Lardone E, Boschelle C, Mantuano E, Veneziano L, Manni L. Construction and preliminary characterization of human recombinant proNGF-A variant. Neurochem Int 2020; 140:104812. [PMID: 32758589 DOI: 10.1016/j.neuint.2020.104812] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 06/27/2020] [Accepted: 07/10/2020] [Indexed: 11/18/2022]
Abstract
The precursor of Nerve Growth Factor (proNGF) is the predominant form of NGF in the brain, where its tissue levels are increased in neurodegenerative diseases. proNGF exists in two main splicing variants, the long proNGF-A and the short proNGF-B. We demonstrated that proNGF-B is selectively increased in the hippocampus of rats affected by early diabetic encephalopathy and that native, purified proNGFs elicit different responses when used to stimulate PC12 cells. Therefore, the evaluation of the proNGF-B/proNGF-A ratio may be of important diagnostic and prognostic value in pathologies characterized by dysfunctions of NGF system. To date there is not clear pharmacological characterization of the different proNGFs variants, due to the lack of a proper recombinant proNGF-A. Using a bioinformatics approach, we predicted aminoacid sites involved in proNGF-A intracellular cleavage/conversion into proNGF-B, we cloned and expressed non-cleavable proNGF-A in HeLa cells and pursued a first characterization of their secretion modalities. Finally, we studied the biological effects of different proNGF-A mutants, stimulating PC12 cells with conditioned media from transfected HeLa cells. Based on our results, we propose the A73Y mutation as essential to obtaining an intact proNGF-A, limiting its conversion to proNGF-B. proNGF-A A73Y is probably released in an activity dependent manner and, when supplied to PC12 cells, shows a moderate differentiative capacity opposed to high neuroprotective potential. This preliminary study lays the foundation for future research aimed at uncovering the selective biological activities of proNGF-A and proNGF-B, and at developing pharmacological treatments that target the unbalance of proNGF system, induced by neurodegeneration.
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Affiliation(s)
- Marzia Soligo
- Institute of Translational Pharmacology, Consiglio Nazionale Delle Ricerche (CNR), Rome, Italy
| | - Antonio Chiaretti
- Institute of Pediatrics, Università Cattolica Del Sacro Cuore, Rome, Italy
| | - Eleonora Leotta
- Institute of Translational Pharmacology, Consiglio Nazionale Delle Ricerche (CNR), Rome, Italy
| | - Elena Lardone
- Institute of Translational Pharmacology, Consiglio Nazionale Delle Ricerche (CNR), Rome, Italy
| | - Chiara Boschelle
- Institute of Translational Pharmacology, Consiglio Nazionale Delle Ricerche (CNR), Rome, Italy
| | - Elide Mantuano
- Institute of Translational Pharmacology, Consiglio Nazionale Delle Ricerche (CNR), Rome, Italy
| | - Liana Veneziano
- Institute of Translational Pharmacology, Consiglio Nazionale Delle Ricerche (CNR), Rome, Italy
| | - Luigi Manni
- Institute of Translational Pharmacology, Consiglio Nazionale Delle Ricerche (CNR), Rome, Italy.
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9
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Kim KJ, Kim JW, Sung JH, Suh KJ, Lee JY, Kim SH, Lee JO, Kim JW, Kim YJ, Kim JH, Bang SM, Lee JS, Kim HK, Lee KW. PI3K-targeting strategy using alpelisib to enhance the antitumor effect of paclitaxel in human gastric cancer. Sci Rep 2020; 10:12308. [PMID: 32704014 PMCID: PMC7378194 DOI: 10.1038/s41598-020-68998-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 07/03/2020] [Indexed: 02/06/2023] Open
Abstract
PIK3CA mutations are frequently observed in various human cancers including gastric cancer (GC). This study was conducted to investigate the anti-tumor effects of alpelisib, a PI3K p110α-specific inhibitor, using preclinical models of GC. In addition, the combined effects of alpelisib and paclitaxel on GC were evaluated. Among the SNU1, SNU16, SNU484, SNU601, SNU638, SNU668, AGS, and MKN1 GC cells, three PIK3CA-mutant cells were predominantly sensitive to alpelisib. Alpelisib monotherapy decreased AKT and S6K1 phosphorylation and induced G0/G1 phase arrest regardless of PIK3CA mutational status. The alpelisib and paclitaxel combination demonstrated synergistic anti-proliferative effects, preferentially on PIK3CA-mutant cells, resulting in increased DNA damage response and apoptosis. In addition, alpelisib and paclitaxel combination potentiated anti-migratory activity in PIK3CA-mutant cells. Alpelisib partially reversed epithelial–mesenchymal transition markers in PIK3CA-mutant cells. In a xenograft model of MKN1 cells, the alpelisib and paclitaxel combination significantly enhanced anti-tumor activity by decreasing Ki-67 expression and increasing apoptosis. Moreover, this combination tended to prolong the survival of tumor-bearing mice. Our data suggest promising anti-tumor efficacy of alpelisib alone or in combination with paclitaxel in PIK3CA-mutant GC cells.
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Affiliation(s)
- Kui-Jin Kim
- Biomedical Research Institute, Seoul National University Bundang Hospital, Seongnam, 13620, Republic of Korea
| | - Ji-Won Kim
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, 82 Gumi-ro 173 Beon-gil Bundang-gu, Seongnam, 13620, Republic of Korea
| | - Ji Hea Sung
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, 82 Gumi-ro 173 Beon-gil Bundang-gu, Seongnam, 13620, Republic of Korea
| | - Koung Jin Suh
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, 82 Gumi-ro 173 Beon-gil Bundang-gu, Seongnam, 13620, Republic of Korea
| | - Ji Yun Lee
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, 82 Gumi-ro 173 Beon-gil Bundang-gu, Seongnam, 13620, Republic of Korea
| | - Se Hyun Kim
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, 82 Gumi-ro 173 Beon-gil Bundang-gu, Seongnam, 13620, Republic of Korea
| | - Jeong-Ok Lee
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, 82 Gumi-ro 173 Beon-gil Bundang-gu, Seongnam, 13620, Republic of Korea
| | - Jin Won Kim
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, 82 Gumi-ro 173 Beon-gil Bundang-gu, Seongnam, 13620, Republic of Korea
| | - Yu Jung Kim
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, 82 Gumi-ro 173 Beon-gil Bundang-gu, Seongnam, 13620, Republic of Korea
| | - Jee Hyun Kim
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, 82 Gumi-ro 173 Beon-gil Bundang-gu, Seongnam, 13620, Republic of Korea
| | - Soo-Mee Bang
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, 82 Gumi-ro 173 Beon-gil Bundang-gu, Seongnam, 13620, Republic of Korea
| | - Jong Seok Lee
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, 82 Gumi-ro 173 Beon-gil Bundang-gu, Seongnam, 13620, Republic of Korea
| | - Hark Kyun Kim
- National Cancer Center Graduate School of Cancer Science and Policy, National Cancer Center, Goyang, 10408, Republic of Korea
| | - Keun-Wook Lee
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, 82 Gumi-ro 173 Beon-gil Bundang-gu, Seongnam, 13620, Republic of Korea.
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10
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Haseeb A, Lefebvre V. The SOXE transcription factors-SOX8, SOX9 and SOX10-share a bi-partite transactivation mechanism. Nucleic Acids Res 2020; 47:6917-6931. [PMID: 31194875 PMCID: PMC6649842 DOI: 10.1093/nar/gkz523] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 05/23/2019] [Accepted: 06/03/2019] [Indexed: 12/20/2022] Open
Abstract
SOX8, SOX9 and SOX10 compose the SOXE transcription factor group. They govern cell fate and differentiation in many lineages, and mutations impairing their activity cause severe diseases, including campomelic dysplasia (SOX9), sex determination disorders (SOX8 and SOX9) and Waardenburg-Shah syndrome (SOX10). However, incomplete knowledge of their modes of action limits disease understanding. We here uncover that the proteins share a bipartite transactivation mechanism, whereby a transactivation domain in the middle of the proteins (TAM) synergizes with a C-terminal one (TAC). TAM comprises amphipathic α-helices predicted to form a protein-binding pocket and overlapping with minimal transactivation motifs (9-aa-TAD) described in many transcription factors. One 9-aa-TAD sequence includes an evolutionarily conserved and functionally required EΦ[D/E]QYΦ motif. SOXF proteins (SOX7, SOX17 and SOX18) contain an identical motif, suggesting evolution from a common ancestor already harboring this motif, whereas TAC and other transactivating SOX proteins feature only remotely related motifs. Missense variants in this SOXE/SOXF-specific motif are rare in control individuals, but have been detected in cancers, supporting its importance in development and physiology. By deepening understanding of mechanisms underlying the central transactivation function of SOXE proteins, these findings should help further decipher molecular networks essential for development and health and dysregulated in diseases.
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Affiliation(s)
- Abdul Haseeb
- Department of Surgery/Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Véronique Lefebvre
- Department of Surgery/Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
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11
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HiBiT-qIP, HiBiT-based quantitative immunoprecipitation, facilitates the determination of antibody affinity under immunoprecipitation conditions. Sci Rep 2019; 9:6895. [PMID: 31053795 PMCID: PMC6499798 DOI: 10.1038/s41598-019-43319-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 01/31/2019] [Indexed: 12/23/2022] Open
Abstract
The affinity of an antibody for its antigen serves as a critical parameter for antibody evaluation. The evaluation of antibody-antigen affinity is essential for a successful antibody-based assay, particularly immunoprecipitation (IP), due to its strict dependency on antibody performance. However, the determination of antibody affinity or its quantitative determinant, the dissociation constant (Kd), under IP conditions is difficult. In the current study, we used a NanoLuc-based HiBiT system to establish a HiBiT-based quantitative immunoprecipitation (HiBiT-qIP) assay for determining the Kd of antigen-antibody interactions in solution. The HiBiT-qIP method measures the amount of immunoprecipitated proteins tagged with HiBiT in a simple yet quantitative manner. We used this method to measure the Kd values of epitope tag-antibody interactions. To accomplish this, FLAG, HA, V5, PA and Ty1 epitope tags in their monomeric, dimeric or trimeric form were fused with glutathione S-transferase (GST) and the HiBiT peptide, and these tagged GST proteins were mixed with cognate monoclonal antibodies in IP buffer for the assessment of the apparent Kd values. This HiBiT-qIP assay showed a considerable variation in the Kd values among the examined antibody clones. Additionally, the use of epitope tags in multimeric form revealed a copy number-dependent increase in the apparent affinity.
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12
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Pfeiffer A, Thalheimer FB, Hartmann S, Frank AM, Bender RR, Danisch S, Costa C, Wels WS, Modlich U, Stripecke R, Verhoeyen E, Buchholz CJ. In vivo generation of human CD19-CAR T cells results in B-cell depletion and signs of cytokine release syndrome. EMBO Mol Med 2018; 10:e9158. [PMID: 30224381 PMCID: PMC6220327 DOI: 10.15252/emmm.201809158] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Revised: 08/14/2018] [Accepted: 08/17/2018] [Indexed: 12/21/2022] Open
Abstract
Chimeric antigen receptor (CAR) T cells brought substantial benefit to patients with B-cell malignancies. Notwithstanding, CAR T-cell manufacturing requires complex procedures impeding the broad supply chain. Here, we provide evidence that human CD19-CAR T cells can be generated directly in vivo using the lentiviral vector CD8-LV specifically targeting human CD8+ cells. Administration into mice xenografted with Raji lymphoma cells and human peripheral blood mononuclear cells led to CAR expression solely in CD8+ T cells and efficacious elimination of CD19+ B cells. Further, upon injection of CD8-LV into mice transplanted with human CD34+ cells, induction of CAR T cells and CD19+ B-cell depletion was observed in 7 out of 10 treated animals. Notably, three mice showed elevated levels of human cytokines in plasma. Tissue-invading CAR T cells and complete elimination of the B-lymphocyte-rich zones in spleen were indicative of a cytokine release syndrome. Our data demonstrate the feasibility of in vivo reprogramming of human CD8+ CAR T cells active against CD19+ cells, yet with similar adverse effects currently notorious in the clinical practice.
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Affiliation(s)
- Anett Pfeiffer
- Molecular Biotechnology and Gene Therapy, Paul-Ehrlich-Institut, Langen, Germany
| | | | - Sylvia Hartmann
- Dr. Senckenberg Institute of Pathology, Goethe-University Frankfurt, Frankfurt am Main, Germany
| | - Annika M Frank
- Molecular Biotechnology and Gene Therapy, Paul-Ehrlich-Institut, Langen, Germany
| | - Ruben R Bender
- Molecular Biotechnology and Gene Therapy, Paul-Ehrlich-Institut, Langen, Germany
| | - Simon Danisch
- Department of Hematology, Hemostasis, Oncology and Stem Cell Transplantation, Laboratory of Regenerative Immune Therapies Applied, Excellence Cluster REBIRTH and German Centre for Infection Research (DZIF), partner site Hannover, Hannover, Germany
| | - Caroline Costa
- CIRI - International Center for Infectiology Research, Team EVIR, Inserm, U1111, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon 1, University of Lyon, Lyon, France
| | - Winfried S Wels
- Institute for Tumor Biology and Experimental Therapy, Georg-Speyer-Haus, Frankfurt, Germany
- German Cancer Consortium (DKTK), partner site Frankfurt/Mainz, Frankfurt, Germany
- German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Ute Modlich
- Division of Veterinary Medicine, Research Group for Gene Modification in Stem Cells, Paul-Ehrlich-Institut, Langen, Germany
| | - Renata Stripecke
- Department of Hematology, Hemostasis, Oncology and Stem Cell Transplantation, Laboratory of Regenerative Immune Therapies Applied, Excellence Cluster REBIRTH and German Centre for Infection Research (DZIF), partner site Hannover, Hannover, Germany
| | - Els Verhoeyen
- CIRI - International Center for Infectiology Research, Team EVIR, Inserm, U1111, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon 1, University of Lyon, Lyon, France
- INSERM, C3M, Université Côte d'Azur, Nice, France
| | - Christian J Buchholz
- Molecular Biotechnology and Gene Therapy, Paul-Ehrlich-Institut, Langen, Germany
- German Cancer Research Center (DKFZ), Heidelberg, Germany
- German Cancer Consortium (DKTK), partner site Heidelberg, Heidelberg, Germany
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13
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Dong TX, Othy S, Jairaman A, Skupsky J, Zavala A, Parker I, Dynes JL, Cahalan MD. T-cell calcium dynamics visualized in a ratiometric tdTomato-GCaMP6f transgenic reporter mouse. eLife 2017; 6:32417. [PMID: 29239725 PMCID: PMC5747524 DOI: 10.7554/elife.32417] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 12/11/2017] [Indexed: 11/13/2022] Open
Abstract
Calcium is an essential cellular messenger that regulates numerous functions in living organisms. Here, we describe development and characterization of ‘Salsa6f’, a fusion of GCaMP6f and tdTomato optimized for cell tracking while monitoring cytosolic Ca2+, and a transgenic Ca2+ reporter mouse with Salsa6f targeted to the Rosa26 locus for Cre-dependent expression in specific cell types. The development and function of T cells was unaffected in Cd4-Salsa6f mice. We describe Ca2+ signals reported by Salsa6f during T cell receptor activation in naive T cells, helper Th17 T cells and regulatory T cells, and Ca2+ signals mediated in T cells by an activator of mechanosensitive Piezo1 channels. Transgenic expression of Salsa6f enables ratiometric imaging of Ca2+ signals in complex tissue environments found in vivo. Two-photon imaging of migrating T cells in the steady-state lymph node revealed both cell-wide and localized sub-cellular Ca2+ transients (‘sparkles’) as cells migrate. To help protect the body from disease, small immune cells called T lymphocytes move rapidly, searching for signs of infection. These signs are antigens – processed pieces of proteins from invading bacteria and viruses – which are displayed on the surface of so-called antigen-presenting cells. To visit as many different antigen-presenting cells as possible, T cells move quickly from one to the next in an apparently random manner. How T cells are programmed to move in this way is largely unknown. The entry of calcium ions into cells, through channel proteins, triggers characteristic actions in many cells throughout the body. As such it is possible that the T cells’ movements are related to calcium signals too. However, it was technically challenging to directly measure the amount of calcium in moving cells within the body. To overcome this issue, Dong, Othy et al. genetically engineered mice to produce a new calcium-sensitive reporter protein in their T cells. The reporter, which was named Salsa6f, consisted of a red fluorescent protein fused to another protein that glows green when it binds to calcium ions. Measuring the ratio of red and green fluorescence gives a measure of the concentration of calcium ions inside the cell. In the absence of calcium signaling, the cells can still be tracked via the red fluorescence of Salsa6f. Importantly, the reporter did not affect the development or activity of the T cells in the mice. In a related study, Dong, Othy et al. then used their transgenic mice to ask whether calcium signals guide moving T cells as they search for antigens. Future studies could use these transgenic mice to track the calcium ion concentration in numerous cell types. This would enable new approaches to relate the inner workings of cells to their behaviors in many different organ systems throughout the body.
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Affiliation(s)
- Tobias X Dong
- Department of Physiology and Biophysics, University of California, Irvine, United States
| | - Shivashankar Othy
- Department of Physiology and Biophysics, University of California, Irvine, United States
| | - Amit Jairaman
- Department of Physiology and Biophysics, University of California, Irvine, United States
| | - Jonathan Skupsky
- Department of Physiology and Biophysics, University of California, Irvine, United States.,Department of Medicine, University of California, Irvine, United States
| | - Angel Zavala
- Department of Physiology and Biophysics, University of California, Irvine, United States
| | - Ian Parker
- Department of Physiology and Biophysics, University of California, Irvine, United States.,Department of Neurobiology & Behavior, University of California, Irvine, United States
| | - Joseph L Dynes
- Department of Physiology and Biophysics, University of California, Irvine, United States
| | - Michael D Cahalan
- Department of Physiology and Biophysics, University of California, Irvine, United States.,Institute for Immunology, University of California, Irvine, United States
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14
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Sizemore RJ, Seeger-Armbruster S, Hughes SM, Parr-Brownlie LC. Viral vector-based tools advance knowledge of basal ganglia anatomy and physiology. J Neurophysiol 2016; 115:2124-46. [PMID: 26888111 PMCID: PMC4869490 DOI: 10.1152/jn.01131.2015] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 02/16/2016] [Indexed: 01/07/2023] Open
Abstract
Viral vectors were originally developed to deliver genes into host cells for therapeutic potential. However, viral vector use in neuroscience research has increased because they enhance interpretation of the anatomy and physiology of brain circuits compared with conventional tract tracing or electrical stimulation techniques. Viral vectors enable neuronal or glial subpopulations to be labeled or stimulated, which can be spatially restricted to a single target nucleus or pathway. Here we review the use of viral vectors to examine the structure and function of motor and limbic basal ganglia (BG) networks in normal and pathological states. We outline the use of viral vectors, particularly lentivirus and adeno-associated virus, in circuit tracing, optogenetic stimulation, and designer drug stimulation experiments. Key studies that have used viral vectors to trace and image pathways and connectivity at gross or ultrastructural levels are reviewed. We explain how optogenetic stimulation and designer drugs used to modulate a distinct pathway and neuronal subpopulation have enhanced our mechanistic understanding of BG function in health and pathophysiology in disease. Finally, we outline how viral vector technology may be applied to neurological and psychiatric conditions to offer new treatments with enhanced outcomes for patients.
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Affiliation(s)
- Rachel J Sizemore
- Department of Anatomy, Otago School of Medical Sciences, Brain Health Research Centre, Brain Research New Zealand, University of Otago, Dunedin, New Zealand
| | - Sonja Seeger-Armbruster
- Department of Physiology, Otago School of Medical Sciences, Brain Health Research Centre, Brain Research New Zealand, University of Otago, Dunedin, New Zealand; and
| | - Stephanie M Hughes
- Department of Biochemistry, Otago School of Medical Sciences, Brain Health Research Centre, Brain Research New Zealand, University of Otago, Dunedin, New Zealand
| | - Louise C Parr-Brownlie
- Department of Anatomy, Otago School of Medical Sciences, Brain Health Research Centre, Brain Research New Zealand, University of Otago, Dunedin, New Zealand;
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15
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Valentini P, Pompa PP. A Universal Polymerase Chain Reaction Developer. Angew Chem Int Ed Engl 2015; 55:2157-60. [DOI: 10.1002/anie.201511010] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Indexed: 11/10/2022]
Affiliation(s)
- Paola Valentini
- Istituto Italiano di Tecnologia (IIT); Via Morego, 30 16163 Genova Italy
| | - Pier Paolo Pompa
- Istituto Italiano di Tecnologia (IIT); Via Morego, 30 16163 Genova Italy
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16
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Affiliation(s)
- Paola Valentini
- Istituto Italiano di Tecnologia (IIT); Via Morego, 30 16163 Genova Italy
| | - Pier Paolo Pompa
- Istituto Italiano di Tecnologia (IIT); Via Morego, 30 16163 Genova Italy
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17
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Fouz M, Mukumoto K, Averick S, Molinar O, McCartney BM, Matyjaszewski K, Armitage BA, Das SR. Bright Fluorescent Nanotags from Bottlebrush Polymers with DNA-Tipped Bristles. ACS CENTRAL SCIENCE 2015; 1:431-8. [PMID: 27163005 PMCID: PMC4827471 DOI: 10.1021/acscentsci.5b00259] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Indexed: 05/30/2023]
Abstract
Bright signal outputs are needed for fluorescence detection of biomolecules at their native expression levels. Increasing the number of labels on a probe often results in crowding-induced self-quenching of chromophores, and maintaining the function of the targeting moiety (e.g., an antibody) is a concern. Here we demonstrate a simple method to accommodate thousands of fluorescent dye molecules on a single antibody probe while avoiding the negative effects of self-quenching. We use a bottlebrush polymer from which extend hundreds of duplex DNA strands that can accommodate hundreds of covalently attached and/or thousands of noncovalently intercalated fluorescent dyes. This polymer-DNA assembly sequesters the intercalated fluorophores against dissociation and can be tethered through DNA hybridization to an IgG antibody. The resulting fluorescent nanotag can detect protein targets in flow cytometry, confocal fluorescence microscopy, and dot blots with an exceptionally bright signal that compares favorably to commercially available antibodies labeled with organic dyes or quantum dots.
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Affiliation(s)
- Munira
F. Fouz
- Department of Chemistry, Center for Nucleic Acids Science
and Technology, Center for Macromolecular
Engineering, and Department of Biological Sciences, Carnegie
Mellon University, 4400
Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Kosuke Mukumoto
- Department of Chemistry, Center for Nucleic Acids Science
and Technology, Center for Macromolecular
Engineering, and Department of Biological Sciences, Carnegie
Mellon University, 4400
Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Saadyah Averick
- Department of Chemistry, Center for Nucleic Acids Science
and Technology, Center for Macromolecular
Engineering, and Department of Biological Sciences, Carnegie
Mellon University, 4400
Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Olivia Molinar
- Department of Chemistry, Center for Nucleic Acids Science
and Technology, Center for Macromolecular
Engineering, and Department of Biological Sciences, Carnegie
Mellon University, 4400
Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Brooke M. McCartney
- Department of Chemistry, Center for Nucleic Acids Science
and Technology, Center for Macromolecular
Engineering, and Department of Biological Sciences, Carnegie
Mellon University, 4400
Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Krzysztof Matyjaszewski
- Department of Chemistry, Center for Nucleic Acids Science
and Technology, Center for Macromolecular
Engineering, and Department of Biological Sciences, Carnegie
Mellon University, 4400
Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Bruce A. Armitage
- Department of Chemistry, Center for Nucleic Acids Science
and Technology, Center for Macromolecular
Engineering, and Department of Biological Sciences, Carnegie
Mellon University, 4400
Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Subha R. Das
- Department of Chemistry, Center for Nucleic Acids Science
and Technology, Center for Macromolecular
Engineering, and Department of Biological Sciences, Carnegie
Mellon University, 4400
Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
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18
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Civiero L, Cirnaru MD, Beilina A, Rodella U, Russo I, Belluzzi E, Lobbestael E, Reyniers L, Hondhamuni G, Lewis PA, Van den Haute C, Baekelandt V, Bandopadhyay R, Bubacco L, Piccoli G, Cookson MR, Taymans JM, Greggio E. Leucine-rich repeat kinase 2 interacts with p21-activated kinase 6 to control neurite complexity in mammalian brain. J Neurochem 2015; 135:1242-56. [PMID: 26375402 PMCID: PMC4715492 DOI: 10.1111/jnc.13369] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2015] [Revised: 08/01/2015] [Accepted: 09/04/2015] [Indexed: 12/23/2022]
Abstract
Leucine‐rich repeat kinase 2 (LRRK2) is a causative gene for Parkinson's disease, but the physiological function and the mechanism(s) by which the cellular activity of LRRK2 is regulated are poorly understood. Here, we identified p21‐activated kinase 6 (PAK6) as a novel interactor of the GTPase/ROC domain of LRRK2. p21‐activated kinases are serine‐threonine kinases that serve as targets for the small GTP binding proteins Cdc42 and Rac1 and have been implicated in different morphogenetic processes through remodeling of the actin cytoskeleton such as synapse formation and neuritogenesis. Using an in vivo neuromorphology assay, we show that PAK6 is a positive regulator of neurite outgrowth and that LRRK2 is required for this function. Analyses of post‐mortem brain tissue from idiopathic and LRRK2 G2019S carriers reveal an increase in PAK6 activation state, whereas knock‐out LRRK2 mice display reduced PAK6 activation and phosphorylation of PAK6 substrates. Taken together, these results support a critical role of LRRK2 GTPase domain in cytoskeletal dynamics in vivo through the novel interactor PAK6, and provide a valuable platform to unravel the mechanism underlying LRRK2‐mediated pathophysiology.
We propose p21‐activated kinase 6 (PAK6) as a novel interactor of leucine‐rich repeat kinase 2 (LRRK2), a kinase involved in Parkinson's disease (PD). In health, PAK6 regulates neurite complexity in the brain and LRRK2 is required for its function, (a) whereas PAK6 is aberrantly activated in LRRK2‐linked PD brain (b) suggesting that LRRK2 toxicity is mediated by PAK6.
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Affiliation(s)
- Laura Civiero
- Department of Biology, University of Padova, Padova, Italy
| | | | - Alexandra Beilina
- Laboratory of Neurogenetics, National Institute on Aging/NIH, Bethesda, Maryland, USA
| | - Umberto Rodella
- Department of Biology, University of Padova, Padova, Italy.,Laboratory for Neurobiology and Gene Therapy, KU Leuven, Leuven, Belgium
| | - Isabella Russo
- Department of Biology, University of Padova, Padova, Italy
| | - Elisa Belluzzi
- Department of Biology, University of Padova, Padova, Italy
| | - Evy Lobbestael
- Laboratory for Neurobiology and Gene Therapy, KU Leuven, Leuven, Belgium
| | - Lauran Reyniers
- Laboratory for Neurobiology and Gene Therapy, KU Leuven, Leuven, Belgium
| | - Geshanthi Hondhamuni
- Department of Molecular Neuroscience UCL, Reta Lila Weston Institute of Neurological Studies, Institute of Neurology, London, UK
| | - Patrick A Lewis
- School of Pharmacy, University of Reading, Reading, UK.,Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, UK
| | - Chris Van den Haute
- Laboratory for Neurobiology and Gene Therapy, KU Leuven, Leuven, Belgium.,Leuven Viral Vector Core, KU Leuven, Leuven, Belgium
| | - Veerle Baekelandt
- Laboratory for Neurobiology and Gene Therapy, KU Leuven, Leuven, Belgium
| | - Rina Bandopadhyay
- Department of Molecular Neuroscience UCL, Reta Lila Weston Institute of Neurological Studies, Institute of Neurology, London, UK
| | - Luigi Bubacco
- Department of Biology, University of Padova, Padova, Italy
| | - Giovanni Piccoli
- San Raffaele Science Park and Università Vita-Salute San Raffaele, Milano, Italy
| | - Mark R Cookson
- Laboratory of Neurogenetics, National Institute on Aging/NIH, Bethesda, Maryland, USA
| | - Jean-Marc Taymans
- Laboratory for Neurobiology and Gene Therapy, KU Leuven, Leuven, Belgium
| | - Elisa Greggio
- Department of Biology, University of Padova, Padova, Italy
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19
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Kerr N, Holmes FE, Hobson SA, Vanderplank P, Leard A, Balthasar N, Wynick D. The generation of knock-in mice expressing fluorescently tagged galanin receptors 1 and 2. Mol Cell Neurosci 2015; 68:258-71. [PMID: 26292267 PMCID: PMC4604734 DOI: 10.1016/j.mcn.2015.08.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 08/06/2015] [Accepted: 08/10/2015] [Indexed: 12/12/2022] Open
Abstract
The neuropeptide galanin has diverse roles in the central and peripheral nervous systems, by activating the G protein-coupled receptors Gal1, Gal2 and the less studied Gal3 (GalR1-3 gene products). There is a wealth of data on expression of Gal1-3 at the mRNA level, but not at the protein level due to the lack of specificity of currently available antibodies. Here we report the generation of knock-in mice expressing Gal1 or Gal2 receptor fluorescently tagged at the C-terminus with, respectively, mCherry or hrGFP (humanized Renilla green fluorescent protein). In dorsal root ganglia (DRG) neurons expressing the highest levels of Gal1-mCherry, localization to the somatic cell membrane was detected by live-cell fluorescence and immunohistochemistry, and that fluorescence decreased upon addition of galanin. In spinal cord, abundant Gal1-mCherry immunoreactive processes were detected in the superficial layers of the dorsal horn, and highly expressing intrinsic neurons of the lamina III/IV border showed both somatic cell membrane localization and outward transport of receptor from the cell body, detected as puncta within cell processes. In brain, high levels of Gal1-mCherry immunofluorescence were detected within thalamus, hypothalamus and amygdala, with a high density of nerve endings in the external zone of the median eminence, and regions with lesser immunoreactivity included the dorsal raphe nucleus. Gal2-hrGFP mRNA was detected in DRG, but live-cell fluorescence was at the limits of detection, drawing attention to both the much lower mRNA expression than to Gal1 in mice and the previously unrecognized potential for translational control by upstream open reading frames (uORFs).
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MESH Headings
- Animals
- Brain/metabolism
- Cells, Cultured
- Ganglia, Spinal/cytology
- Green Fluorescent Proteins/genetics
- Green Fluorescent Proteins/metabolism
- Luminescent Proteins/genetics
- Luminescent Proteins/metabolism
- Mice
- Mice, Transgenic
- Microscopy, Confocal
- Neurons/physiology
- RNA, Messenger/metabolism
- Receptor, Galanin, Type 1/genetics
- Receptor, Galanin, Type 1/metabolism
- Receptor, Galanin, Type 2/genetics
- Receptor, Galanin, Type 2/metabolism
- Spinal Cord/metabolism
- Red Fluorescent Protein
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Affiliation(s)
- Niall Kerr
- Schools of Physiology and Pharmacology and Clinical Sciences, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - Fiona E Holmes
- Schools of Physiology and Pharmacology and Clinical Sciences, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - Sally-Ann Hobson
- Schools of Physiology and Pharmacology and Clinical Sciences, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - Penny Vanderplank
- Schools of Physiology and Pharmacology and Clinical Sciences, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - Alan Leard
- Wolfson Bioimaging Facility, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - Nina Balthasar
- Schools of Physiology and Pharmacology and Clinical Sciences, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - David Wynick
- Schools of Physiology and Pharmacology and Clinical Sciences, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK.
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20
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Parr-Brownlie LC, Bosch-Bouju C, Schoderboeck L, Sizemore RJ, Abraham WC, Hughes SM. Lentiviral vectors as tools to understand central nervous system biology in mammalian model organisms. Front Mol Neurosci 2015; 8:14. [PMID: 26041987 PMCID: PMC4434958 DOI: 10.3389/fnmol.2015.00014] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 04/30/2015] [Indexed: 01/18/2023] Open
Abstract
Lentiviruses have been extensively used as gene delivery vectors since the mid-1990s. Usually derived from the human immunodeficiency virus genome, they mediate efficient gene transfer to non-dividing cells, including neurons and glia in the adult mammalian brain. In addition, integration of the recombinant lentiviral construct into the host genome provides permanent expression, including the progeny of dividing neural precursors. In this review, we describe targeted vectors with modified envelope glycoproteins and expression of transgenes under the regulation of cell-selective and inducible promoters. This technology has broad utility to address fundamental questions in neuroscience and we outline how this has been used in rodents and primates. Combining viral tract tracing with immunohistochemistry and confocal or electron microscopy, lentiviral vectors provide a tool to selectively label and trace specific neuronal populations at gross or ultrastructural levels. Additionally, new generation optogenetic technologies can be readily utilized to analyze neuronal circuit and gene functions in the mature mammalian brain. Examples of these applications, limitations of current systems and prospects for future developments to enhance neuroscience knowledge will be reviewed. Finally, we will discuss how these vectors may be translated from gene therapy trials into the clinical setting.
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Affiliation(s)
- Louise C. Parr-Brownlie
- Department of Anatomy, Brain Health Research Centre, University of OtagoDunedin, New Zealand
- Brain Research New Zealand Centre of Research ExcellenceDunedin, New Zealand
| | | | - Lucia Schoderboeck
- Brain Research New Zealand Centre of Research ExcellenceDunedin, New Zealand
- Department of Biochemistry, Brain Health Research Centre, University of OtagoDunedin, New Zealand
- Department of Psychology, Brain Health Research Centre, University of OtagoDunedin, New Zealand
| | - Rachel J. Sizemore
- Department of Anatomy, Brain Health Research Centre, University of OtagoDunedin, New Zealand
- Brain Research New Zealand Centre of Research ExcellenceDunedin, New Zealand
| | - Wickliffe C. Abraham
- Brain Research New Zealand Centre of Research ExcellenceDunedin, New Zealand
- Department of Psychology, Brain Health Research Centre, University of OtagoDunedin, New Zealand
| | - Stephanie M. Hughes
- Brain Research New Zealand Centre of Research ExcellenceDunedin, New Zealand
- Department of Biochemistry, Brain Health Research Centre, University of OtagoDunedin, New Zealand
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21
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Interleukin 1 type 1 receptor restore: a genetic mouse model for studying interleukin 1 receptor-mediated effects in specific cell types. J Neurosci 2015; 35:2860-70. [PMID: 25698726 DOI: 10.1523/jneurosci.3199-14.2015] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Interleukin-1 (IL-1) mediates diverse neurophysiological and neuropathological effects in the CNS through type I IL-1 receptor (IL-1R1). However, identification of IL-1R1-expressing cell types and cell-type-specific functions of IL-1R1 remains challenging. In this study, we created a novel genetic mouse model in which IL-1R1 gene expression is disrupted by an intronic insertion of a loxP flanked disruptive sequence that can be deleted by Cre recombinase, resulting in restored IL-1R1 gene expression under its endogenous promoters. A second mutation was introduced at stop codon of the IL-1R1 gene to allow tracking of the restored IL-1R1 protein by a 3HA tag and IL-1R1 mRNA by tdTomato fluorescence. These animals were designated as IL-1R1(r/r) and exhibited an IL-1R1 knock-out phenotype. We used IL-1R1 globally restored mice (IL-1R1(GR/GR)) as an IL-1R1 reporter and observed concordant labeling of IL-1R1 mRNA and protein in brain endothelial cells. Two cell-type-specific IL-1R1 restore lines were generated: Tie2Cre-IL-1R1(r/r) and LysMCre-IL-1R1(r/r). Brain endothelial COX-2 expression, CNS leukocyte infiltration, and global microglia activation induced by intracerebroventricular injection of IL-1β were not observed in IL-1R1(r/r) or LysMCre-IL-1R1(r/r) mice, but were restored in Tie2Cre-IL-1R1(r/r) mice. These results reveal IL-1R1 expression in endothelial cells alone is sufficient to mediate these central IL-1-induced responses. In addition, ex vivo IL-1β stimulation increased IL-1β expression in bone marrow cells in wild-type, Tie2Cre-IL-1R1(r/r), and LysMCre-IL-1R1(r/r), but not IL-1R1(r/r) mice. These results demonstrate this IL-1R1 restore model is a valuable tool for studying cell-type-specific functions of IL-1R1.
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Jun LS, Showalter AD, Ali N, Dai F, Ma W, Coskun T, Ficorilli JV, Wheeler MB, Michael MD, Sloop KW. A novel humanized GLP-1 receptor model enables both affinity purification and Cre-LoxP deletion of the receptor. PLoS One 2014; 9:e93746. [PMID: 24695667 PMCID: PMC3973576 DOI: 10.1371/journal.pone.0093746] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 03/07/2014] [Indexed: 12/25/2022] Open
Abstract
Class B G protein-coupled receptors (GPCRs) are important regulators of endocrine physiology, and peptide-based therapeutics targeting some of these receptors have proven effective at treating disorders such as hypercalcemia, osteoporosis, and type 2 diabetes mellitus (T2DM). As next generation efforts attempt to develop novel non-peptide, orally available molecules for these GPCRs, new animal models expressing human receptor orthologs may be required because small molecule ligands make fewer receptor contacts, and thus, the impact of amino acid differences across species may be substantially greater. The objective of this report was to generate and characterize a new mouse model of the human glucagon-like peptide-1 receptor (hGLP-1R), a class B GPCR for which established peptide therapeutics exist for the treatment of T2DM. hGLP-1R knock-in mice express the receptor from the murine Glp-1r locus. Glucose tolerance tests and gastric emptying studies show hGLP-1R mice and their wild-type littermates display similar physiological responses for glucose metabolism, insulin secretion, and gastric transit, and treatment with the GLP-1R agonist, exendin-4, elicits similar responses in both groups. Further, ex vivo assays show insulin secretion from humanized islets is glucose-dependent and enhanced by GLP-1R agonists. To enable additional utility, the targeting construct of the knock-in line was engineered to contain both flanking LoxP sites and a C-terminal FLAG epitope. Anti-FLAG affinity purification shows strong expression of hGLP-1R in islets, lung, and stomach. We crossed the hGLP-1R line with Rosa26Cre mice and generated global Glp-1r-/- animals. Immunohistochemistry of pancreas from humanized and knock-out mice identified a human GLP-1R-specific antibody that detects the GLP-1R in human pancreas as well as in the pancreas of hGLP-1r knock-in mice. This new hGLP-1R model will allow tissue-specific deletion of the GLP-1R, purification of potential GLP-1R partner proteins, and testing of novel therapeutic agents targeting the hGLP-1R.
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Affiliation(s)
- Lucy S. Jun
- Endocrine Discovery, Lilly Research Laboratories, Eli Lilly and Co., Indianapolis, Indiana, United States of America
| | - Aaron D. Showalter
- Endocrine Discovery, Lilly Research Laboratories, Eli Lilly and Co., Indianapolis, Indiana, United States of America
| | - Nosher Ali
- Endocrine Discovery, Lilly Research Laboratories, Eli Lilly and Co., Indianapolis, Indiana, United States of America
| | - Feihan Dai
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Wenzhen Ma
- Endocrine Discovery, Lilly Research Laboratories, Eli Lilly and Co., Indianapolis, Indiana, United States of America
| | - Tamer Coskun
- Endocrine Discovery, Lilly Research Laboratories, Eli Lilly and Co., Indianapolis, Indiana, United States of America
| | - James V. Ficorilli
- Endocrine Discovery, Lilly Research Laboratories, Eli Lilly and Co., Indianapolis, Indiana, United States of America
| | - Michael B. Wheeler
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - M. Dodson Michael
- Endocrine Discovery, Lilly Research Laboratories, Eli Lilly and Co., Indianapolis, Indiana, United States of America
| | - Kyle W. Sloop
- Endocrine Discovery, Lilly Research Laboratories, Eli Lilly and Co., Indianapolis, Indiana, United States of America
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23
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Dujardin S, Lécolle K, Caillierez R, Bégard S, Zommer N, Lachaud C, Carrier S, Dufour N, Aurégan G, Winderickx J, Hantraye P, Déglon N, Colin M, Buée L. Neuron-to-neuron wild-type Tau protein transfer through a trans-synaptic mechanism: relevance to sporadic tauopathies. Acta Neuropathol Commun 2014; 2:14. [PMID: 24479894 PMCID: PMC3922636 DOI: 10.1186/2051-5960-2-14] [Citation(s) in RCA: 181] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 01/16/2014] [Indexed: 12/31/2022] Open
Abstract
Background In sporadic Tauopathies, neurofibrillary degeneration (NFD) is characterised by the intraneuronal aggregation of wild-type Tau proteins. In the human brain, the hierarchical pathways of this neurodegeneration have been well established in Alzheimer’s disease (AD) and other sporadic tauopathies such as argyrophilic grain disorder and progressive supranuclear palsy but the molecular and cellular mechanisms supporting this progression are yet not known. These pathways appear to be associated with the intercellular transmission of pathology, as recently suggested in Tau transgenic mice. However, these conclusions remain ill-defined due to a lack of toxicity data and difficulties associated with the use of mutant Tau. Results Using a lentiviral-mediated rat model of hippocampal NFD, we demonstrated that wild-type human Tau protein is axonally transferred from ventral hippocampus neurons to connected secondary neurons even at distant brain areas such as olfactory and limbic systems indicating a trans-synaptic protein transfer. Using different immunological tools to follow phospho-Tau species, it was clear that Tau pathology generated using mutated Tau remains near the IS whereas it spreads much further using the wild-type one. Conclusion Taken together, these results support a novel mechanism for Tau protein transfer compared to previous reports based on transgenic models with mutant cDNA. It also demonstrates that mutant Tau proteins are not suitable for the development of experimental models helpful to validate therapeutic intervention interfering with Tau spreading.
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24
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Taymans JM, Gao F, Baekelandt V. Metabolic labeling of leucine rich repeat kinases 1 and 2 with radioactive phosphate. J Vis Exp 2013:e50523. [PMID: 24084685 DOI: 10.3791/50523] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Leucine rich repeat kinases 1 and 2 (LRRK1 and LRRK2) are paralogs which share a similar domain organization, including a serine-threonine kinase domain, a Ras of complex proteins domain (ROC), a C-terminal of ROC domain (COR), and leucine-rich and ankyrin-like repeats at the N-terminus. The precise cellular roles of LRRK1 and LRRK2 have yet to be elucidated, however LRRK1 has been implicated in tyrosine kinase receptor signaling, while LRRK2 is implicated in the pathogenesis of Parkinson's disease. In this report, we present a protocol to label the LRRK1 and LRRK2 proteins in cells with (32)P orthophosphate, thereby providing a means to measure the overall phosphorylation levels of these 2 proteins in cells. In brief, affinity tagged LRRK proteins are expressed in HEK293T cells which are exposed to medium containing (32)P-orthophosphate. The (32)P-orthophosphate is assimilated by the cells after only a few hours of incubation and all molecules in the cell containing phosphates are thereby radioactively labeled. Via the affinity tag (3xflag) the LRRK proteins are isolated from other cellular components by immunoprecipitation. Immunoprecipitates are then separated via SDS-PAGE, blotted to PVDF membranes and analysis of the incorporated phosphates is performed by autoradiography ((32)P signal) and western detection (protein signal) of the proteins on the blots. The protocol can readily be adapted to monitor phosphorylation of any other protein that can be expressed in cells and isolated by immunoprecipitation.
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Affiliation(s)
- Jean-Marc Taymans
- Laboratory for Neurobiology and Gene Therapy, Department of Neurosciences, KU Leuven and Leuven Institute for Neuroscience and Disease (LIND)
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25
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Li X, DeJoseph M, Urban JH, Bahi A, Dreyer JL, Meredith GE, Ford KA, Ferrario CR, Loweth JA, Wolf ME. Different roles of BDNF in nucleus accumbens core versus shell during the incubation of cue-induced cocaine craving and its long-term maintenance. J Neurosci 2013; 33:1130-42. [PMID: 23325250 PMCID: PMC3711541 DOI: 10.1523/jneurosci.3082-12.2013] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Revised: 10/09/2012] [Accepted: 11/19/2012] [Indexed: 12/13/2022] Open
Abstract
Brain-derived neurotrophic factor (BDNF) contributes to diverse types of plasticity, including cocaine addiction. We investigated the role of BDNF in the rat nucleus accumbens (NAc) in the incubation of cocaine craving over 3 months of withdrawal from extended access cocaine self-administration. First, we confirmed by immunoblotting that BDNF levels are elevated after this cocaine regimen on withdrawal day 45 (WD45) and showed that BDNF mRNA levels are not altered. Next, we explored the time course of elevated BDNF expression using immunohistochemistry. Elevation of BDNF in the NAc core was detected on WD45 and further increased on WD90, whereas elevation in shell was not detected until WD90. Surface expression of activated tropomyosin receptor kinase B (TrkB) was also enhanced on WD90. Next, we used viral vectors to attenuate BDNF-TrkB signaling. Virus injection into the NAc core enhanced cue-induced cocaine seeking on WD1 compared with controls, whereas no effect was observed on WD30 or WD90. Attenuating BDNF-TrkB signaling in shell did not affect cocaine seeking on WD1 or WD45 but significantly decreased cocaine seeking on WD90. These results suggest that basal levels of BDNF transmission in the NAc core exert a suppressive effect on cocaine seeking in early withdrawal (WD1), whereas the late elevation of BDNF protein in NAc shell contributes to incubation in late withdrawal (WD90). Finally, BDNF protein levels in the NAc were significantly increased after ampakine treatment, supporting the novel hypothesis that the gradual increase of BDNF levels in NAc accompanying incubation could be caused by increased AMPAR transmission during withdrawal.
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Affiliation(s)
| | | | | | - Amine Bahi
- Department of Anatomy, United Arab Emirates University, Alabama-Ain, United Arab Emirates, and
| | - Jean-Luc Dreyer
- Division of Biochemistry, Department of Medicine, University of Fribourg, CH-1700 Fribourg, Switzerland
| | - Gloria E. Meredith
- Pharmaceutical Sciences, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois 60064
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26
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Askin SP, Schaeffer PM. A universal immuno-PCR platform for comparative and ultrasensitive quantification of dual affinity-tagged proteins in complex matrices. Analyst 2012; 137:5193-6. [DOI: 10.1039/c2an35857c] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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27
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Wehrhan F, Amann K, Molenberg A, Lutz R, Neukam FW, Schlegel KA. PEG matrix enables cell-mediated local BMP-2 gene delivery and increased bone formation in a porcine critical size defect model of craniofacial bone regeneration. Clin Oral Implants Res 2011; 23:805-13. [PMID: 22151397 DOI: 10.1111/j.1600-0501.2011.02223.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/06/2011] [Indexed: 01/19/2023]
Abstract
PURPOSE This study addressed the suitability of a polyethylene glycol (PEG) matrix as scaffold for cell-mediated local BMP-2 gene transfer in a calvarial critical size defect (CSD) model. MATERIALS AND METHODS PEG matrix (degradation time 10 days) and PEG membrane (degradation time 120 days) were used in the pig calvarial model. Cylindrical (1 × 1 cm) CSD (9 per animal; 20 animals) were filled with: (i) HA/TCP, covered by PEG membrane (group 1); (ii) HA/TCP, mixed with PEG matrix (group 2); and (iii) HA/TCP mixed with BMP-2 transfected osteoblasts and PEG matrix (group 3). BMP-2/4 gene transfer: liposomal in vitro transfection of BMP-2/V5-tag fusion-protein. Quantitative histomorphometry (toluidine blue staining) after 2, 4 and 12 weeks assessed bone formation. Semiquantitative immunohistochemistry estimated the expression of BMP-2 and V5-tag. RESULTS Group 3 showed significantly higher new bone formation than groups 1, 2 at 4 (P < 0.05) and 12 (P < 0.02) weeks. BMP-2-V5-tag was detected for 4 weeks. BMP-2 expression in group 3 was higher compared to all other groups after 2 and 4 (P < 0.02) weeks. CONCLUSIONS The PEG matrix serves as scaffold for cell-mediated BMP-2 gene delivery in guided bone regeneration facilitating cell survival and protein synthesis for at least 4 weeks. Local BMP-2 gene delivery by PEG matrix-embedded cells leads to increased bone formation during critical size defect regeneration.
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Affiliation(s)
- Falk Wehrhan
- Department of Oral and Maxillofacial Surgery, University of Erlangen-Nuremberg, Erlangen, Germany.
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28
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Blevins KS, Jeong JH, Ou M, Brumbach JH, Kim SW. EphA2 targeting peptide tethered bioreducible poly(cystamine bisacrylamide-diamino hexane) for the delivery of therapeutic pCMV-RAE-1γ to pancreatic islets. J Control Release 2011; 158:115-22. [PMID: 22062690 DOI: 10.1016/j.jconrel.2011.10.022] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Revised: 10/17/2011] [Accepted: 10/20/2011] [Indexed: 02/05/2023]
Abstract
The pathogenesis of type-1 diabetes is complicated, and a clear, single mechanism has yet to be identified. Reports have indicated that the activating receptor NKG2D plays an important role in the development of disease. Exploiting a natural phenomenon observed in tumors, plasmid DNA encoding for a soluble ligand to NKG2D (sRAE-1γ) was isolated and engineered into a plasmid expression system. A polymeric gene delivery system was developed to deliver the soluble RAE-1 plasmid locally to the pancreatic islets for the prevention of type-1 diabetes. The bioreducible cationic polymer poly(cystamine bisacrylamide-diamino hexane) (p(CBA-DAH)) was modified with poly(ethylene glycol) (PEG) and the targeting peptide CHVLWSTRC, known to target the EphA2 and EphA4 receptors. The PEG serves to improve stability and tissue selectivity, while the peptide will target EphA2 and A4, overexpressed in the pancreatic microvasculature. The targeting polymer Eph-PEG-p(CBA-DAH) shows selective uptake by the target cell line, indicative of the targeting properties that will be seen in systemic administration. Using the delivery system, the therapeutic plasmid can be delivered to the pancreas, reduce interactions between the beta-cells and infiltrating NKG2D positive lymphocytes, and effectively protect beta-cells from autoimmune destruction and prevent type 1 diabetes.
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Affiliation(s)
- Katherine S Blevins
- Department of Bioengineering, University of Utah, 20 South 2030 East, Salt Lake City, UT 84112-5820, USA
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29
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Yu H, Fischer G, Jia G, Reiser J, Park F, Hogan QH. Lentiviral gene transfer into the dorsal root ganglion of adult rats. Mol Pain 2011; 7:63. [PMID: 21861915 PMCID: PMC3179738 DOI: 10.1186/1744-8069-7-63] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Accepted: 08/23/2011] [Indexed: 12/20/2022] Open
Abstract
Background Lentivector-mediated gene delivery into the dorsal root ganglion (DRG) is a promising method for exploring pain pathophysiology and for genetic treatment of chronic neuropathic pain. In this study, a series of modified lentivector particles with different cellular promoters, envelope glycoproteins, and viral accessory proteins were generated to evaluate the requirements for efficient transduction into neuronal cells in vitro and adult rat DRG in vivo. Results In vitro, lentivectors expressing enhanced green fluorescent protein (EGFP) under control of the human elongation factor 1α (EF1α) promoter and pseudotyped with the conventional vesicular stomatitis virus G protein (VSV-G) envelope exhibited the best performance in the transfer of EGFP into an immortalized DRG sensory neuron cell line at low multiplicities of infection (MOIs), and into primary cultured DRG neurons at higher MOIs. In vivo, injection of either first or second-generation EF1α-EGFP lentivectors directly into adult rat DRGs led to transduction rates of 19 ± 9% and 20 ± 8% EGFP-positive DRG neurons, respectively, detected at 4 weeks post injection. Transduced cells included a full range of neuronal phenotypes, including myelinated neurons as well as both non-peptidergic and peptidergic nociceptive unmyelinated neurons. Conclusion VSV-G pseudotyped lentivectors containing the human elongation factor 1α (EF1α)-EGFP expression cassette demonstrated relatively efficient transduction to sensory neurons following direct injection into the DRG. These results clearly show the potential of lentivectors as a viable system for delivering target genes into DRGs to explore basic mechanisms of neuropathic pain, with the potential for future clinical use in treating chronic pain.
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Affiliation(s)
- Hongwei Yu
- Department of Anesthesiology, Medical College of Wisconsin, 8100 Watertown Plank Rd, Milwaukee, Wisconsin 53226, USA
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30
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Lee WJ, Kraus P, Lufkin T. Endogenous tagging of the murine transcription factor Sox5 with hemaglutinin for functional studies. Transgenic Res 2011; 21:293-301. [PMID: 21732189 DOI: 10.1007/s11248-011-9531-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Accepted: 06/13/2011] [Indexed: 01/21/2023]
Abstract
Gene expression is usually studied at the transcript level rather than at the protein level due to the lack of a specific and sensitive antibody. A way to overcome this is to fuse to the protein of interest an immunoreactive tag that has well-characterized antibodies. This epitope tagging approach is often used for in vitro experiments but for in vivo studies, the success rate of protein tagging has not been extensively analyzed and our study seeks to cover the void. A small epitope, hemaglutinin derived from the influenza virus was used to tag a transcription factor, Sox5 at the N-terminal via homologous recombination in the mouse. Sox5 is part of the Sry-related high-mobility-group box gene family and plays multiple roles in essential biological processes. Understanding of its molecular function in relation to its biological roles remains incomplete. In our study, we show that the longer isoform of Sox5 can be tagged endogenously with hemaglutinin without affecting its biological function in vivo. The tagged protein is easily and specifically detected with an anti-hemaglutinin antibody using immunohistochemistry with its expression matching the endogenous expression of Sox5. Immunoprecipitation of Sox5 was also carried out successfully using an anti-hemaglutinin antibody. The transgenic line generated from this study is predicted to be useful for future experiments such as co-immunoprecipitation and chromatin immunoprecipitation, allowing the further understanding of Sox5. Lastly, this approach can be easily employed for the investigation of other transcription factors and proteins in vivo to overcome technical limitations such as antibody cross-reactivity and to perform isoform-specific studies.
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Affiliation(s)
- Wenqing Jean Lee
- Stem Cell and Developmental Biology, Genome Institute of Singapore, 60 Biopolis Street, Singapore, 138672, Singapore
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31
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One-step split GFP staining for sensitive protein detection and localization in mammalian cells. Biotechniques 2011; 49:727-8, 730, 732 passim. [PMID: 20964633 DOI: 10.2144/000113512] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Although epitope tags are useful to detect intracellular proteins and follow their localization with antibodies, background and nonspecific staining often remain problematic. We describe a simple assay based on the split GFP complementation system. Proteins tagged with the 15-amino acid GFP 11 fragment are detected with a solution of the recombinant nonfluorescent complementary GFP 1-10 fragment to reconstitute a fluorescent GFP. In contrast to antibody-based staining methods, this one-step assay presents high specificity and very low background of fluorescence, thus conferring higher signal-to-noise ratios. We demonstrate that this new application of the split GFP tagging system facilitates detection of proteins displaying various subcellular localizations using flow cytometry and microscopy analysis.
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