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Jang SI, Jo JH, Claudine U, Jung EJ, Lee WJ, Hwang JM, Bae JW, Kim DH, Yi JK, Ha JJ, Oh DY, Kwon WS. Correlation between Rab3A Expression and Sperm Kinematic
Characteristics. Dev Reprod 2024; 28:13-19. [PMID: 38654977 PMCID: PMC11034992 DOI: 10.12717/dr.2024.28.1.13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 02/09/2024] [Accepted: 02/22/2024] [Indexed: 04/26/2024]
Abstract
Ras-related (Rab) proteins, integral members of the monomeric G-protein family, play a pivotal role in regulating intracellular vesicular transport. These proteins contribute to male reproductive processes, specifically in acrosome formation, exocytosis, and sperm motility. Although a prior study indicated a correlation between Rab3A and sperm motility, including motion kinematic parameters such as mean dance, this association has only been explored within a limited sample size. Therefore, further verification is required to confirm the correlation between Rab3A and sperm motility parameters. In the present study, Rab3A expression, sperm motility, and motion kinematic parameters were analyzed in 150 boar spermatozoa. Additionally, correlations between Rab3A expression and sperm kinematic characteristics were evaluated statistically. The results revealed significant associations between Rab3A protein expression levels and various motion kinematic parameters. Specifically, Rab3A levels exhibited positive correlations with average path velocity (p <0.05), mean amplitude of lateral head displacement (p <0.05), and curvilinear velocity (p <0.01). Consequently, it is proposed that Rab3A protein plays a crucial role in male fertility through its correlation with sperm kinematic characteristics, making it a potential marker for sperm motility-related assessments.
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Affiliation(s)
- Seung-Ik Jang
- Department of Animal Science and
Biotechnology, Kyungpook National University,
Sangju 37224, Korea
| | - Jae-Hwan Jo
- Department of Animal Biotechnology,
Kyungpook National University, Sangju 37224,
Korea
| | - Uwamahoro Claudine
- Department of Animal Science and
Biotechnology, Kyungpook National University,
Sangju 37224, Korea
| | - Eun-Ju Jung
- Department of Animal Science and
Biotechnology, Kyungpook National University,
Sangju 37224, Korea
| | - Woo-Jin Lee
- Department of Animal Science and
Biotechnology, Kyungpook National University,
Sangju 37224, Korea
| | - Ju-Mi Hwang
- Department of Animal Science and
Biotechnology, Kyungpook National University,
Sangju 37224, Korea
| | - Jeong-Won Bae
- Department of Animal Science and
Biotechnology, Kyungpook National University,
Sangju 37224, Korea
| | - Dae-Hyun Kim
- Department of Animal Science, Chonnam
National University, Gwangju 61186,
Korea
| | - Jun Koo Yi
- School of Animal Life Convergence
Science, Hankyong National University, Anseong
17579, Korea
| | - Jae Jung Ha
- Gyeongbuk Livestock Research
Institute, Yeongju 36052, Korea
| | - Dong Yep Oh
- Gyeongbuk Livestock Research
Institute, Yeongju 36052, Korea
| | - Woo-Sung Kwon
- Department of Animal Science and
Biotechnology, Kyungpook National University,
Sangju 37224, Korea
- Department of Animal Biotechnology,
Kyungpook National University, Sangju 37224,
Korea
- Research Institute for Innovative Animal
Science, Kyungpook National University, Sangju
37224, Korea
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Verkhratsky A, Butt A, Li B, Illes P, Zorec R, Semyanov A, Tang Y, Sofroniew MV. Astrocytes in human central nervous system diseases: a frontier for new therapies. Signal Transduct Target Ther 2023; 8:396. [PMID: 37828019 PMCID: PMC10570367 DOI: 10.1038/s41392-023-01628-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 08/15/2023] [Accepted: 08/22/2023] [Indexed: 10/14/2023] Open
Abstract
Astroglia are a broad class of neural parenchymal cells primarily dedicated to homoeostasis and defence of the central nervous system (CNS). Astroglia contribute to the pathophysiology of all neurological and neuropsychiatric disorders in ways that can be either beneficial or detrimental to disorder outcome. Pathophysiological changes in astroglia can be primary or secondary and can result in gain or loss of functions. Astroglia respond to external, non-cell autonomous signals associated with any form of CNS pathology by undergoing complex and variable changes in their structure, molecular expression, and function. In addition, internally driven, cell autonomous changes of astroglial innate properties can lead to CNS pathologies. Astroglial pathophysiology is complex, with different pathophysiological cell states and cell phenotypes that are context-specific and vary with disorder, disorder-stage, comorbidities, age, and sex. Here, we classify astroglial pathophysiology into (i) reactive astrogliosis, (ii) astroglial atrophy with loss of function, (iii) astroglial degeneration and death, and (iv) astrocytopathies characterised by aberrant forms that drive disease. We review astroglial pathophysiology across the spectrum of human CNS diseases and disorders, including neurotrauma, stroke, neuroinfection, autoimmune attack and epilepsy, as well as neurodevelopmental, neurodegenerative, metabolic and neuropsychiatric disorders. Characterising cellular and molecular mechanisms of astroglial pathophysiology represents a new frontier to identify novel therapeutic strategies.
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Affiliation(s)
- Alexei Verkhratsky
- International Joint Research Centre on Purinergic Signalling/School of Health and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu, China.
- Department of Forensic Analytical Toxicology, School of Forensic Medicine, China Medical University, Shenyang, China.
- Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK.
- Achucarro Centre for Neuroscience, IKERBASQUE, Basque Foundation for Science, Bilbao, Spain.
- Department of Stem Cell Biology, State Research Institute Centre for Innovative Medicine, LT-01102, Vilnius, Lithuania.
| | - Arthur Butt
- Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, UK
| | - Baoman Li
- Department of Forensic Analytical Toxicology, School of Forensic Medicine, China Medical University, Shenyang, China
| | - Peter Illes
- International Joint Research Centre on Purinergic Signalling/School of Health and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu, China
- Rudolf Boehm Institute for Pharmacology and Toxicology, University of Leipzig, 04109, Leipzig, Germany
| | - Robert Zorec
- Celica Biomedical, Lab Cell Engineering, Technology Park, 1000, Ljubljana, Slovenia
- Laboratory of Neuroendocrinology-Molecular Cell Physiology, Institute of Pathophysiology, University of Ljubljana, Faculty of Medicine, Ljubljana, Slovenia
| | - Alexey Semyanov
- Department of Physiology, Jiaxing University College of Medicine, 314033, Jiaxing, China
| | - Yong Tang
- International Joint Research Centre on Purinergic Signalling/School of Health and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu, China.
- Key Laboratory of Acupuncture for Senile Disease (Chengdu University of TCM), Ministry of Education/Acupuncture and Chronobiology Key Laboratory of Sichuan Province, Chengdu, China.
| | - Michael V Sofroniew
- Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA.
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Bae JW, Yi JK, Jeong EJ, Lee WJ, Hwang JM, Kim DH, Ha JJ, Kwon WS. Ras-related proteins (Rab) play significant roles in sperm motility and capacitation status. Reprod Biol 2022; 22:100617. [PMID: 35180576 DOI: 10.1016/j.repbio.2022.100617] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/23/2022] [Accepted: 02/07/2022] [Indexed: 11/29/2022]
Abstract
Rab proteins are widely known for their involvement in establishing Golgi apparatus and controlling Golgi trafficking in eukaryotic cells. Specifically, Rab proteins play significant roles in acrosome formation and exocytosis. Furthermore, mechanisms involved in the regulation of Rab proteins during capacitation have been identified. However, there has been no direct evaluation to assess the correlation between Rab proteins and sperm function. Consequently, this study was designed to analyze the correlation between Rab proteins and sperm functions. Individually, we analyzed the sperm motility patterns, motion kinematics, capacitation status, and Rab protein expression levels of sperm samples from 31 boars before and after capacitation. As a result, we discovered that Rab3A, Rab5, Rab11, Rab14, and Rab27A correlated with various sperm motility patterns, motion kinematics before capacitation. Rab3A, Rab5, Rab11, Rab14, and Rab34 correlated with various sperm motility patterns, motion kinematics after capacitation. Moreover, Rab4 and Rab34 were associated with capacitation status before capacitation, and Rab3A, 25, and 27A correlated with capacitation status after capacitation. This is the first study to analyze the correlation between Rab proteins and sperm functions. Collectively, our results indicate that specific sperm motility and kinematics, as well as the structural condition of the sperm head and capacitation status, regulate individual Rab protein. Therefore, we expect that the current findings will be used to identify the etiology of idiopathic male infertility patients and to diagnose male fertility and that Rab proteins will be employed as biomarkers to predict and analyze male fertility.
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Affiliation(s)
- Jeong-Won Bae
- Department of Animal Science and Biotechnology, Kyungpook National University, Sangju, Gyeongsangbuk-do, 37224, Republic of Korea
| | - Jun Koo Yi
- Gyeongbuk Livestock Research Institute, Yeongju, Gyeongsangbuk-do, 36052, Republic of Korea
| | - Eun-Ju Jeong
- Department of Animal Biotechnology, Kyungpook National University, Sangju, Gyeongsangbuk-do, 37224, Republic of Korea
| | - Woo-Jin Lee
- Department of Animal Science and Biotechnology, Kyungpook National University, Sangju, Gyeongsangbuk-do, 37224, Republic of Korea
| | - Ju-Mi Hwang
- Department of Animal Science and Biotechnology, Kyungpook National University, Sangju, Gyeongsangbuk-do, 37224, Republic of Korea
| | - Dae-Hyun Kim
- Gyeongbuk Livestock Research Institute, Yeongju, Gyeongsangbuk-do, 36052, Republic of Korea
| | - Jae Jung Ha
- Gyeongbuk Livestock Research Institute, Yeongju, Gyeongsangbuk-do, 36052, Republic of Korea
| | - Woo-Sung Kwon
- Department of Animal Science and Biotechnology, Kyungpook National University, Sangju, Gyeongsangbuk-do, 37224, Republic of Korea; Department of Animal Biotechnology, Kyungpook National University, Sangju, Gyeongsangbuk-do, 37224, Republic of Korea.
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Young BK, Shen LL, Del Priore LV. An In Silica Model for RPE Loss Patterns in Choroideremia. Invest Ophthalmol Vis Sci 2021; 62:10. [PMID: 34779822 PMCID: PMC8606796 DOI: 10.1167/iovs.62.14.10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To use empirical data to develop a model of cell loss in choroideremia that predicts the known exponential rate of RPE loss and central, scalloped preservation pattern seen in this disease. Methods A computational model of RPE loss was created in Python 3.7, which constructed an array of RPE cells clusters, binarized as either live or atrophic. Two rules were applied to this model: the background effect gave each cell a chance of dying defined by a background function, and the neighbor effect increased the chance of RPE cell death if a neighbor were dead. The known anatomic distribution of rods, RPE, choriocapillaris density, amacrine, ganglion, and cone cells were derived from the literature and applied to this model. Atrophy growth rates were measured over arbitrary time units and fit to the known exponential decay model. The main outcome measures: included topography of atrophy over time and fit of simulated residual RPE area to exponential decay. Results A background effect alone can simulate exponential decay, but does not simulate the central island preservation seen in choroideremia. An additive neighbor effect alone does not simulate exponential decay. When the neighbor effect multiplies the background effect using the rod density function, our model follows an exponential decay, similar to previous observations. Also, our model predicts a residual island of RPE that resembles the topographic distribution of residual RPE seen in choroideremia. Conclusions The pattern of RPE loss in choroideremia can be predicted by applying simple rules. The RPE preservation pattern typically seen in choroideremia may be related to the underlying pattern of rod density. Further studies are needed to validate these findings.
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Affiliation(s)
- Benjamin K Young
- W.K. Kellogg Eye Center, University of Michigan School of Medicine, Ann Arbor, MI, United States
| | - Liangbo L Shen
- Department of Ophthalmology, University of California San Francisco, San Francisco, San Francisco, CA, United States
| | - Lucian V Del Priore
- Department of Ophthalmology and Visual Sciences, Yale University School of Medicine, New Haven, CT, United States
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Kalatzis V, Roux AF, Meunier I. Molecular Therapy for Choroideremia: Pre-clinical and Clinical Progress to Date. Mol Diagn Ther 2021; 25:661-675. [PMID: 34661884 DOI: 10.1007/s40291-021-00558-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/09/2021] [Indexed: 12/01/2022]
Abstract
Choroideremia is an inherited retinal disease characterised by a degeneration of the light-sensing photoreceptors, supporting retinal pigment epithelium and underlying choroid. Patients present with the same symptoms as those with classic rod-cone dystrophy: (1) night blindness early in life; (2) progressive peripheral visual field loss, and (3) central vision decline with a slow progression to legal blindness. Choroideremia is monogenic and caused by mutations in CHM. Eight clinical trials (three phase 1/2, four phase 2, and one phase 3) have started (four of which are already finished) to evaluate the therapeutic efficacy of gene supplementation mediated by subretinal delivery of an adeno-associated virus serotype 2 (AAV2/2) vector expressing CHM. Furthermore, one phase 1 clinical trial has been initiated to evaluate the efficiency of a novel AAV variant to deliver CHM to the outer retina following intravitreal delivery. Lastly, a non-viral-mediated CHM replacement strategy is currently under development, which could lead to a future clinical trial. Here, we summarise the rationale behind these various studies, as well as any results published to date. The diversity of these trials currently places choroideremia at the forefront of the retinal gene therapy field. As a consequence, the trial outcomes, regardless of the results, have the potential to change the landscape of gene supplementation for inherited retinal diseases.
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Affiliation(s)
- Vasiliki Kalatzis
- Institute for Neurosciences of Montpellier, Univ Montpellier, Inserm U1298, Hôpital St Eloi, 80 Avenue Augustin Fliche, 34091, Montpellier, France.
| | - Anne-Françoise Roux
- Institute for Neurosciences of Montpellier, Univ Montpellier, Inserm U1298, Hôpital St Eloi, 80 Avenue Augustin Fliche, 34091, Montpellier, France.,Molecular Genetics Laboratory, Univ Montpellier, CHU Montpellier, Montpellier, France
| | - Isabelle Meunier
- Institute for Neurosciences of Montpellier, Univ Montpellier, Inserm U1298, Hôpital St Eloi, 80 Avenue Augustin Fliche, 34091, Montpellier, France.,National Reference Centre for Inherited Sensory Diseases, University of Montpellier, CHU Montpellier, Montpellier, France
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6
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Erasmus JC, Smolarczyk K, Brezovjakova H, Mohd-Naim NF, Lozano E, Matter K, Braga VMM. Rac1-PAK1 regulation of Rab11 cycling promotes junction destabilization. J Cell Biol 2021; 220:212034. [PMID: 33914026 PMCID: PMC8091128 DOI: 10.1083/jcb.202002114] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 09/21/2020] [Accepted: 02/04/2021] [Indexed: 12/12/2022] Open
Abstract
Rac1 GTPase is hyperactivated in tumors and contributes to malignancy. Rac1 disruption of junctions requires its effector PAK1, but the precise mechanisms are unknown. Here, we show that E-cadherin is internalized via micropinocytosis in a PAK1–dependent manner without catenin dissociation and degradation. In addition to internalization, PAK1 regulates E-cadherin transport by fine-tuning Rab small GTPase function. PAK1 phosphorylates a core Rab regulator, RabGDIβ, but not RabGDIα. Phosphorylated RabGDIβ preferentially associates with Rab5 and Rab11, which is predicted to promote Rab retrieval from membranes. Consistent with this hypothesis, Rab11 is activated by Rac1, and inhibition of Rab11 function partially rescues E-cadherin destabilization. Thus, Rac1 activation reduces surface cadherin levels as a net result of higher bulk flow of membrane uptake that counteracts Rab11-dependent E-cadherin delivery to junctions (recycling and/or exocytosis). This unique small GTPase crosstalk has an impact on Rac1 and PAK1 regulation of membrane remodeling during epithelial dedifferentiation, adhesion, and motility.
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Affiliation(s)
- Jennifer C Erasmus
- National Heart and Lung Institute, Faculty of Medicine, Imperial College London, London, UK
| | - Kasia Smolarczyk
- National Heart and Lung Institute, Faculty of Medicine, Imperial College London, London, UK
| | - Helena Brezovjakova
- National Heart and Lung Institute, Faculty of Medicine, Imperial College London, London, UK
| | - Noor F Mohd-Naim
- National Heart and Lung Institute, Faculty of Medicine, Imperial College London, London, UK
| | - Encarnación Lozano
- National Heart and Lung Institute, Faculty of Medicine, Imperial College London, London, UK
| | - Karl Matter
- Institute of Ophthalmology, University College London, London, UK
| | - Vania M M Braga
- National Heart and Lung Institute, Faculty of Medicine, Imperial College London, London, UK
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Jamalzadeh S, Pujari AN, Cullen PJ. A Rab escort protein regulates the MAPK pathway that controls filamentous growth in yeast. Sci Rep 2020; 10:22184. [PMID: 33335117 PMCID: PMC7746766 DOI: 10.1038/s41598-020-78470-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 11/18/2020] [Indexed: 12/12/2022] Open
Abstract
MAPK pathways regulate different responses yet can share common components. Although core regulators of MAPK pathways are well known, new pathway regulators continue to be identified. Overexpression screens can uncover new roles for genes in biological processes and are well suited to identify essential genes that cannot be evaluated by gene deletion analysis. In this study, a genome-wide screen was performed to identify genes that, when overexpressed, induce a reporter (FUS1-HIS3) that responds to ERK-type pathways (Mating and filamentous growth or fMAPK) but not p38-type pathways (HOG) in yeast. Approximately 4500 plasmids overexpressing individual yeast genes were introduced into strains containing the reporter by high-throughput transformation. Candidate genes were identified by measuring growth as a readout of reporter activity. Fourteen genes were identified and validated by re-testing: two were metabolic controls (HIS3, ATR1), five had established roles in regulating ERK-type pathways (STE4, STE7, BMH1, BMH2, MIG2) and seven represent potentially new regulators of MAPK signaling (RRN6, CIN5, MRS6, KAR2, TFA1, RSC3, RGT2). MRS6 encodes a Rab escort protein and effector of the TOR pathway that plays a role in nutrient signaling. MRS6 overexpression stimulated invasive growth and phosphorylation of the ERK-type fMAPK, Kss1. Overexpression of MRS6 reduced the osmotolerance of cells and phosphorylation of the p38/HOG MAPK, Hog1. Mrs6 interacted with the PAK kinase Ste20 and MAPKK Ste7 by two-hybrid analysis. Based on these results, Mrs6 may selectively propagate an ERK-dependent signal. Identifying new regulators of MAPK pathways may provide new insights into signal integration among core cellular processes and the execution of pathway-specific responses.
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Affiliation(s)
- Sheida Jamalzadeh
- Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, Buffalo, NY, USA
| | - Atindra N Pujari
- Department of Biological Sciences, State University of New York at Buffalo, 532 Cooke Hall, Buffalo, NY, 14260-1300, USA
| | - Paul J Cullen
- Department of Biological Sciences, State University of New York at Buffalo, 532 Cooke Hall, Buffalo, NY, 14260-1300, USA.
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Hook SC, Chadt A, Heesom KJ, Kishida S, Al-Hasani H, Tavaré JM, Thomas EC. TBC1D1 interacting proteins, VPS13A and VPS13C, regulate GLUT4 homeostasis in C2C12 myotubes. Sci Rep 2020; 10:17953. [PMID: 33087848 PMCID: PMC7578007 DOI: 10.1038/s41598-020-74661-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 09/07/2020] [Indexed: 01/01/2023] Open
Abstract
Proteins involved in the spaciotemporal regulation of GLUT4 trafficking represent potential therapeutic targets for the treatment of insulin resistance and type 2 diabetes. A key regulator of insulin- and exercise-stimulated glucose uptake and GLUT4 trafficking is TBC1D1. This study aimed to identify proteins that regulate GLUT4 trafficking and homeostasis via TBC1D1. Using an unbiased quantitative proteomics approach, we identified proteins that interact with TBC1D1 in C2C12 myotubes including VPS13A and VPS13C, the Rab binding proteins EHBP1L1 and MICAL1, and the calcium pump SERCA1. These proteins associate with TBC1D1 via its phosphotyrosine binding (PTB) domains and their interactions with TBC1D1 were unaffected by AMPK activation, distinguishing them from the AMPK regulated interaction between TBC1D1 and AMPKα1 complexes. Depletion of VPS13A or VPS13C caused a post-transcriptional increase in cellular GLUT4 protein and enhanced cell surface GLUT4 levels in response to AMPK activation. The phenomenon was specific to GLUT4 because other recycling proteins were unaffected. Our results provide further support for a role of the TBC1D1 PTB domains as a scaffold for a range of Rab regulators, and also the VPS13 family of proteins which have been previously linked to fasting glycaemic traits and insulin resistance in genome wide association studies.
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Affiliation(s)
- Sharon C Hook
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, University Walk, Bristol, BS8 1TD, UK
| | - Alexandra Chadt
- Institute of Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University, Medical Faculty, Düsseldorf, Germany
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
| | - Kate J Heesom
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, University Walk, Bristol, BS8 1TD, UK
| | - Shosei Kishida
- Department of Biochemistry and Genetics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Hadi Al-Hasani
- Institute of Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University, Medical Faculty, Düsseldorf, Germany
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
| | - Jeremy M Tavaré
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, University Walk, Bristol, BS8 1TD, UK
| | - Elaine C Thomas
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, University Walk, Bristol, BS8 1TD, UK.
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9
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Fioretti T, Ungari S, Savarese M, Cattaneo F, Pirozzi E, Esposito G. A putative frameshift variant in the CHM gene is associated with an unexpected splicing alteration in a choroideremia patient. Mol Genet Genomic Med 2020; 8:e1490. [PMID: 32949230 PMCID: PMC7667377 DOI: 10.1002/mgg3.1490] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 07/29/2020] [Accepted: 08/10/2020] [Indexed: 12/19/2022] Open
Abstract
Background Due to the limited availability of mRNA analysis data, the number of exonic variants resulting in splicing impairment is underestimated although aberrant splicing correction is a promising therapeutic option to treat monogenic diseases, including choroideremia (CHM), a rare X‐linked eye disorder arising from sequence alteration of the CHM gene. Herein we report an exonic frameshift variant associated with an mRNA splicing alteration that leads to a CHM hypomorphic allele. Methods Total RNA and genomic DNA were extracted from peripheral blood of a patient affected by a mild form of CHM. The CHM gene was analyzed by PCR‐based methods and Sanger sequencing. Results Besides the known c.1335dup frameshift variant, mRNA analysis revealed a splicing alteration that restored the reading frame of the mutant transcript, likely leading to an aberrant protein with residual activity. Bioinformatic analyses identified novel putative exonic splicing enhancer elements and provided clues that also pre‐mRNA secondary structure should be taken into account when exploring splicing mechanisms. Conclusion A careful molecular characterization of the c.1335dup variant's effect explains the relationship between genotype and phenotype severity in a CHM patient and provides new perspectives for the study of therapeutic strategies based on splicing correction in human diseases.
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Affiliation(s)
| | - Silvana Ungari
- Dipartimento di Scienze della Sanità Pubblica e Pediatriche, Azienda Ospedaliera S. Croce e Carle, Cuneo, Italy
| | | | - Fabio Cattaneo
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Naples, Italy
| | - Enza Pirozzi
- Azienda Ospedaliera S. Croce e Carle, Cuneo, Italy
| | - Gabriella Esposito
- CEINGE - Advanced Biotechnologies, Naples, Italy.,Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Naples, Italy
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10
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Yarwood R, Hellicar J, Woodman PG, Lowe M. Membrane trafficking in health and disease. Dis Model Mech 2020; 13:13/4/dmm043448. [PMID: 32433026 PMCID: PMC7197876 DOI: 10.1242/dmm.043448] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Membrane trafficking pathways are essential for the viability and growth of cells, and play a major role in the interaction of cells with their environment. In this At a Glance article and accompanying poster, we outline the major cellular trafficking pathways and discuss how defects in the function of the molecular machinery that mediates this transport lead to various diseases in humans. We also briefly discuss possible therapeutic approaches that may be used in the future treatment of trafficking-based disorders. Summary: This At a Glance article and poster summarise the major intracellular membrane trafficking pathways and associated molecular machineries, and describe how defects in these give rise to disease in humans.
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Affiliation(s)
- Rebecca Yarwood
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, UK
| | - John Hellicar
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, UK
| | - Philip G Woodman
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, UK
| | - Martin Lowe
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, UK
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11
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Ras-related proteins (Rab) are key proteins related to male fertility following a unique activation mechanism. Reprod Biol 2019; 19:356-362. [DOI: 10.1016/j.repbio.2019.10.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 09/30/2019] [Accepted: 10/02/2019] [Indexed: 12/16/2022]
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12
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Edler E, Stein M. Recognition and stabilization of geranylgeranylated human Rab5 by the GDP Dissociation Inhibitor (GDI). Small GTPases 2019; 10:227-242. [PMID: 29065764 PMCID: PMC6548291 DOI: 10.1080/21541248.2017.1371268] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 08/18/2017] [Accepted: 08/18/2017] [Indexed: 01/13/2023] Open
Abstract
The small GTPase Rab5 is the key regulator of early endosomal fusion. It is post-translationally modified by covalent attachment of two geranylgeranyl (GG) chains to adjacent cysteine residues of the C-terminal hypervariable region (HVR). The GDP dissociation inhibitor (GDI) recognizes membrane-associated Rab5(GDP) and serves to release it into the cytoplasm where it is kept in a soluble state. A detailed new structural and dynamic model for human Rab5(GDP) recognition and binding with human GDI at the early endosome membrane and in its dissociated state is presented. In the cytoplasm, the GDI protein accommodates the GG chains in a transient hydrophobic binding pocket. In solution, two different binding modes of the isoprenoid chains inserted into the hydrophobic pocket of the Rab5(GDP):GDI complex can be identified. This equilibrium between the two states helps to stabilize the protein-protein complex in solution. Interprotein contacts between the Rab5 switch regions and characteristic patches of GDI residues from the Rab binding platform (RBP) and the C-terminus coordinating region (CCR) reveal insight on the formation of such a stable complex. GDI binding to membrane-anchored Rab5(GDP) is initially mediated by the solvent accessible switch regions of the Rab-specific RBP. Formation of the membrane-associated Rab5(GDP):GDI complex induces a GDI reorientation to establish additional interactions with the Rab5 HVR. These results allow to devise a detailed structural model for the process of extraction of GG-Rab5(GDP) by GDI from the membrane and the dissociation from targeting factors and effector proteins prior to GDI binding.
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Affiliation(s)
- Eileen Edler
- Molecular Simulations and Design Group, Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
| | - Matthias Stein
- Molecular Simulations and Design Group, Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
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13
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Kulakowski G, Bousquet H, Manneville J, Bassereau P, Goud B, Oesterlin LK. Lipid packing defects and membrane charge control RAB GTPase recruitment. Traffic 2018; 19:536-545. [PMID: 29573133 PMCID: PMC6032855 DOI: 10.1111/tra.12568] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 03/15/2018] [Accepted: 03/16/2018] [Indexed: 12/21/2022]
Abstract
Specific intracellular localization of RAB GTPases has been reported to be dependent on protein factors, but the contribution of the membrane physicochemical properties to this process has been poorly described. Here, we show that three RAB proteins (RAB1/RAB5/RAB6) preferentially bind in vitro to disordered and curved membranes, and that this feature is uniquely dependent on their prenyl group. Our results imply that the addition of a prenyl group confers to RAB proteins, and most probably also to other prenylated proteins, the ability to sense lipid packing defects induced by unsaturated conical-shaped lipids and curvature. Consistently, RAB recruitment increases with the amount of lipid packing defects, further indicating that these defects drive RAB membrane targeting. Membrane binding of RAB35 is also modulated by lipid packing defects but primarily dependent on negatively charged lipids. Our results suggest that a balance between hydrophobic insertion of the prenyl group into lipid packing defects and electrostatic interactions of the RAB C-terminal region with charged membranes tunes the specific intracellular localization of RAB proteins.
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Affiliation(s)
- Guillaume Kulakowski
- Institut CurieParis Sciences et Lettres Research University, Sorbonne Université, CNRS UMR144ParisFrance
| | - Hugo Bousquet
- Institut CurieParis Sciences et Lettres Research University, Sorbonne Université, CNRS UMR144ParisFrance
| | - Jean‐Baptiste Manneville
- Institut CurieParis Sciences et Lettres Research University, Sorbonne Université, CNRS UMR144ParisFrance
| | - Patricia Bassereau
- Laboratoire Physico Chimie, Institut CurieParis Sciences et Lettres Research University, Sorbonne Université, CNRS UMR168ParisFrance
| | - Bruno Goud
- Institut CurieParis Sciences et Lettres Research University, Sorbonne Université, CNRS UMR144ParisFrance
| | - Lena K. Oesterlin
- Institut CurieParis Sciences et Lettres Research University, Sorbonne Université, CNRS UMR144ParisFrance
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14
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Patrício MI, Barnard AR, Xue K, MacLaren RE. Choroideremia: molecular mechanisms and development of AAV gene therapy. Expert Opin Biol Ther 2018; 18:807-820. [DOI: 10.1080/14712598.2018.1484448] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Maria I Patrício
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
- National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), Oxford, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Alun R Barnard
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
- National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), Oxford, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Kanmin Xue
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
- National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), Oxford, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Robert E MacLaren
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
- National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), Oxford, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
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15
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Ke H, Feng Z, Liu M, Sun T, Dai J, Ma M, Liu LP, Ni JQ, Pastor-Pareja JC. Collagen secretion screening in Drosophila supports a common secretory machinery and multiple Rab requirements. J Genet Genomics 2018; 45:S1673-8527(18)30097-3. [PMID: 29935791 DOI: 10.1016/j.jgg.2018.05.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Revised: 03/15/2018] [Accepted: 05/04/2018] [Indexed: 12/14/2022]
Abstract
Collagens are large secreted trimeric proteins making up most of the animal extracellular matrix. Secretion of collagen has been a focus of interest for cell biologists in recent years because collagen trimers are too large and rigid to fit into the COPII vesicles mediating transport from the endoplasmic reticulum (ER) to the Golgi. Collagen-specific mechanisms to create enlarged ER-to-Golgi transport carriers have been postulated, including cargo loading by conserved ER exit site (ERES) protein Tango1. Here, we report an RNAi screening for genes involved in collagen secretion in Drosophila. In this screening, we examined distribution of GFP-tagged Collagen IV in live animals and found 88 gene hits for which the knockdown produced intracellular accumulation of Collagen IV in the fat body, the main source of matrix proteins in the larva. Among these hits, only two affected collagen secretion specifically: PH4αEFB and Plod, encoding enzymes known to mediate posttranslational modification of collagen in the ER. Every other intracellular accumulation hit affected general secretion, consistent with the notion that secretion of collagen does not use a specific mode of vesicular transport, but the general secretory pathway. Included in our hits are many known players in the eukaryotic secretory machinery, like COPII and COPI components, SNAREs and Rab-GTPase regulators. Our further analysis of the involvement of Rab-GTPases in secretion shows that Rab1, Rab2 and RabX3, are all required at ERES, each of them differentially affecting ERES morphology. Abolishing activity of all three by Rep knockdown, in contrast, led to uncoupling of ERES and Golgi. We additionally present a characterization of a screening hit we named trabuco (tbc), encoding an ERES-localized TBC domain-containing Rab-GAP. Finally, we discuss the success of our screening in identifying secretory pathway genes in comparison to two previous secretion screenings in Drosophila S2 cells.
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Affiliation(s)
- Hongmei Ke
- School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Zhi Feng
- School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Min Liu
- School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Tianhui Sun
- School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Jianli Dai
- School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Mengqi Ma
- School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Lu-Ping Liu
- School of Medicine, Tsinghua University, Beijing 100084, China
| | - Jian-Quan Ni
- School of Medicine, Tsinghua University, Beijing 100084, China
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16
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Fu X, Huu VAN, Duan Y, Kermany DS, Valentim CCS, Zhang R, Zhu J, Zhang CL, Sun X, Zhang K. Clinical applications of retinal gene therapies. PRECISION CLINICAL MEDICINE 2018; 1:5-20. [PMID: 35694125 PMCID: PMC8982485 DOI: 10.1093/pcmedi/pby004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 03/27/2018] [Accepted: 04/03/2018] [Indexed: 02/05/2023] Open
Abstract
Retinal degenerative diseases are a major cause of blindness. Retinal gene therapy is a
trail-blazer in the human gene therapy field, leading to the first FDA approved gene
therapy product for a human genetic disease. The application of Clustered Regularly
Interspaced Short Palindromic Repeat/Cas9 (CRISPR/Cas9)-mediated gene editing technology
is transforming the delivery of gene therapy. We review the history, present, and future
prospects of retinal gene therapy.
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Affiliation(s)
- Xin Fu
- Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, Guangzhou, China
- Shiley Eye Institute, Institute for Engineering in Medicine, Institute for Genomic Medicine, University of California, San Diego, La Jolla, California, USA
| | - Viet Anh Nguyen Huu
- Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, Guangzhou, China
- Shiley Eye Institute, Institute for Engineering in Medicine, Institute for Genomic Medicine, University of California, San Diego, La Jolla, California, USA
| | - Yaou Duan
- Shiley Eye Institute, Institute for Engineering in Medicine, Institute for Genomic Medicine, University of California, San Diego, La Jolla, California, USA
| | - Daniel S Kermany
- Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, Guangzhou, China
- Shiley Eye Institute, Institute for Engineering in Medicine, Institute for Genomic Medicine, University of California, San Diego, La Jolla, California, USA
| | - Carolina C S Valentim
- Shiley Eye Institute, Institute for Engineering in Medicine, Institute for Genomic Medicine, University of California, San Diego, La Jolla, California, USA
| | - Runze Zhang
- Shiley Eye Institute, Institute for Engineering in Medicine, Institute for Genomic Medicine, University of California, San Diego, La Jolla, California, USA
| | - Jie Zhu
- Shiley Eye Institute, Institute for Engineering in Medicine, Institute for Genomic Medicine, University of California, San Diego, La Jolla, California, USA
| | - Charlotte L Zhang
- Shiley Eye Institute, Institute for Engineering in Medicine, Institute for Genomic Medicine, University of California, San Diego, La Jolla, California, USA
| | - Xiaodong Sun
- Shanghai Key Laboratory of Ocular Fundus Diseases, Shanghai General Hospital, Shanghai Jiaodong University, Shanghai, China
| | - Kang Zhang
- Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, Guangzhou, China
- Shiley Eye Institute, Institute for Engineering in Medicine, Institute for Genomic Medicine, University of California, San Diego, La Jolla, California, USA
- Molecular Medicine Research Center, West China Hospital, Sichuan University, Chengdu, China
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17
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Pylypenko O, Hammich H, Yu IM, Houdusse A. Rab GTPases and their interacting protein partners: Structural insights into Rab functional diversity. Small GTPases 2018. [PMID: 28632484 DOI: 10.1080/215412481336191] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/23/2023] Open
Abstract
Rab molecular switches are key players in defining membrane identity and regulating intracellular trafficking events in eukaryotic cells. In spite of their global structural similarity, Rab-family members acquired particular features that allow them to perform specific cellular functions. The overall fold and local sequence conservations enable them to utilize a common machinery for prenylation and recycling; while individual Rab structural differences determine interactions with specific partners such as GEFs, GAPs and effector proteins. These interactions orchestrate the spatiotemporal regulation of Rab localization and their turning ON and OFF, leading to tightly controlled Rab-specific functionalities such as membrane composition modifications, recruitment of molecular motors for intracellular trafficking, or recruitment of scaffold proteins that mediate interactions with downstream partners, as well as actin cytoskeleton regulation. In this review we summarize structural information on Rab GTPases and their complexes with protein partners in the context of partner binding specificity and functional outcomes of their interactions in the cell.
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Affiliation(s)
- Olena Pylypenko
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
| | - Hussein Hammich
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
- b Sorbonne Universités , UPMC Univ Paris 06, Sorbonne Universités, IFD , Paris , France
| | - I-Mei Yu
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
| | - Anne Houdusse
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
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18
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Gonzalez TL, Sun T, Koeppel AF, Lee B, Wang ET, Farber CR, Rich SS, Sundheimer LW, Buttle RA, Chen YDI, Rotter JI, Turner SD, Williams J, Goodarzi MO, Pisarska MD. Sex differences in the late first trimester human placenta transcriptome. Biol Sex Differ 2018; 9:4. [PMID: 29335024 PMCID: PMC5769539 DOI: 10.1186/s13293-018-0165-y] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 01/03/2018] [Indexed: 12/31/2022] Open
Abstract
Background Development of the placenta during the late first trimester is critical to ensure normal growth and development of the fetus. Developmental differences in this window such as sex-specific variation are implicated in later placental disease states, yet gene expression at this time is poorly understood. Methods RNA-sequencing was performed to characterize the transcriptome of 39 first trimester human placentas using chorionic villi following genetic testing (17 females, 22 males). Gene enrichment analysis was performed to find enriched canonical pathways and gene ontologies in the first trimester. DESeq2 was used to find sexually dimorphic gene expression. Patient demographics were analyzed for sex differences in fetal weight at time of chorionic villus sampling and birth. Results RNA-sequencing analyses detected 14,250 expressed genes, with chromosome 19 contributing the greatest proportion (973/2852, 34.1% of chromosome 19 genes) and Y chromosome contributing the least (16/568, 2.8%). Several placenta-enriched genes as well as histone-coding genes were identified to be unique to the first trimester and common to both sexes. Further, we identified 58 genes with significantly different expression between males and females: 25 X-linked, 15 Y-linked, and 18 autosomal genes. Genes that escape X inactivation were highly represented (59.1%) among X-linked genes upregulated in females. Many genes differentially expressed by sex consisted of X/Y gene pairs, suggesting that dosage compensation plays a role in sex differences. These X/Y pairs had roles in parallel, ancient canonical pathways important for eukaryotic cell growth and survival: chromatin modification, transcription, splicing, and translation. Conclusions This study is the first characterization of the late first trimester placenta transcriptome, highlighting similarities and differences among the sexes in ongoing human pregnancies resulting in live births. Sexual dimorphism may contribute to pregnancy outcomes, including fetal growth and birth weight, which was seen in our cohort, with males significantly heavier than females at birth. This transcriptome provides a basis for development of early diagnostic tests of placental function that can indicate overall pregnancy heath, fetal-maternal health, and long-term adult health. Electronic supplementary material The online version of this article (10.1186/s13293-018-0165-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Tania L Gonzalez
- Department of Obstetrics and Gynecology, Division of Reproductive Endocrinology and Infertility, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Tianyanxin Sun
- Department of Obstetrics and Gynecology, Division of Reproductive Endocrinology and Infertility, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Alexander F Koeppel
- Center for Public Health Genomics, University of Virginia, Charlottesville, VA, USA
| | - Bora Lee
- Department of Obstetrics and Gynecology, Division of Reproductive Endocrinology and Infertility, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Erica T Wang
- Department of Obstetrics and Gynecology, Division of Reproductive Endocrinology and Infertility, Cedars-Sinai Medical Center, Los Angeles, CA, USA.,Division of Reproductive Endocrinology and Infertility, UCLA David Geffen School of Medicine, Los Angeles, CA, USA
| | - Charles R Farber
- Center for Public Health Genomics, University of Virginia, Charlottesville, VA, USA
| | - Stephen S Rich
- Center for Public Health Genomics, University of Virginia, Charlottesville, VA, USA
| | - Lauren W Sundheimer
- Department of Obstetrics and Gynecology, Division of Reproductive Endocrinology and Infertility, Cedars-Sinai Medical Center, Los Angeles, CA, USA.,Division of Reproductive Endocrinology and Infertility, UCLA David Geffen School of Medicine, Los Angeles, CA, USA
| | - Rae A Buttle
- Department of Obstetrics and Gynecology, Division of Reproductive Endocrinology and Infertility, Cedars-Sinai Medical Center, Los Angeles, CA, USA.,Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | | | | | - Stephen D Turner
- Center for Public Health Genomics, University of Virginia, Charlottesville, VA, USA
| | - John Williams
- Department of Obstetrics and Gynecology, Division of Reproductive Endocrinology and Infertility, Cedars-Sinai Medical Center, Los Angeles, CA, USA.,Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Mark O Goodarzi
- Department of Obstetrics and Gynecology, Division of Reproductive Endocrinology and Infertility, Cedars-Sinai Medical Center, Los Angeles, CA, USA.,Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Margareta D Pisarska
- Department of Obstetrics and Gynecology, Division of Reproductive Endocrinology and Infertility, Cedars-Sinai Medical Center, Los Angeles, CA, USA. .,Division of Reproductive Endocrinology and Infertility, UCLA David Geffen School of Medicine, Los Angeles, CA, USA.
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19
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Moore NA, Morral N, Ciulla TA, Bracha P. Gene therapy for inherited retinal and optic nerve degenerations. Expert Opin Biol Ther 2017; 18:37-49. [DOI: 10.1080/14712598.2018.1389886] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Nicholas A. Moore
- Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Nuria Morral
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Thomas A. Ciulla
- Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, IN, USA
- Retina Service, Midwest Eye Institute, Indianapolis, IN, USA
| | - Peter Bracha
- Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, IN, USA
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20
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Duan Y, Lin S, Xie L, Zheng K, Chen S, Song H, Zeng X, Gu X, Wang H, Zhang L, Shao H, Hong W, Zhang L, Duan S. Exome sequencing identifies a novel mutation of the GDI1 gene in a Chinese non-syndromic X-linked intellectual disability family. Genet Mol Biol 2017; 40:591-596. [PMID: 28863211 PMCID: PMC5596370 DOI: 10.1590/1678-4685-gmb-2016-0249] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Accepted: 03/18/2017] [Indexed: 12/29/2022] Open
Abstract
X-linked intellectual disability (XLID) has been associated with various genes.
Diagnosis of XLID, especially for non-syndromic ones (NS-XLID), is often hampered by
the heterogeneity of this disease. Here we report the case of a Chinese family in
which three males suffer from intellectual disability (ID). The three patients shared
the same phenotype: no typical clinical manifestation other than IQ score ≤ 70. For a
genetic diagnosis for this family we carried out whole exome sequencing on the
proband, and validated 16 variants of interest in the genomic DNA of all the family
members. A missense mutation (c.710G > T), which mapped to exon 6 of the Rab
GDP-Dissociation Inhibitor 1 (GDI1) gene, was found segregating with
the ID phenotype, and this mutation changes the 237th position in the guanosine
diphosphate dissociation inhibitor (GDI) protein from glycine to valine (p.
Gly237Val). Through molecular dynamics simulations we found that this substitution
results in a conformational change of GDI, possibly affecting the Rab-binding
capacity of this protein. In conclusion, our study identified a novel
GDI1 mutation that is possibly NS-XLID causative, and showed that
whole exome sequencing provides advantages for detecting novel ID-associated variants
and can greatly facilitate the genetic diagnosis of the disease.
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Affiliation(s)
- Yongheng Duan
- Laboratory of Medical Genetics, Center for Birth Defect Research and Prevention, Shenzhen Research Institute of Population and Family Planning, Shenzhen City, People's Republic of China
| | - Sheng Lin
- Laboratory of Medical Genetics, Center for Birth Defect Research and Prevention, Shenzhen Research Institute of Population and Family Planning, Shenzhen City, People's Republic of China
| | - Lichun Xie
- Laboratory of Medical Genetics, Center for Birth Defect Research and Prevention, Shenzhen Research Institute of Population and Family Planning, Shenzhen City, People's Republic of China
| | - Kaifeng Zheng
- Laboratory of Medical Genetics, Center for Birth Defect Research and Prevention, Shenzhen Research Institute of Population and Family Planning, Shenzhen City, People's Republic of China
| | - Shiguo Chen
- Laboratory of Medical Genetics, Center for Birth Defect Research and Prevention, Shenzhen Research Institute of Population and Family Planning, Shenzhen City, People's Republic of China
| | - Hui Song
- Laboratory of Medical Genetics, Center for Birth Defect Research and Prevention, Shenzhen Research Institute of Population and Family Planning, Shenzhen City, People's Republic of China
| | - Xuchun Zeng
- Laboratory of Medical Genetics, Center for Birth Defect Research and Prevention, Shenzhen Research Institute of Population and Family Planning, Shenzhen City, People's Republic of China
| | - Xueying Gu
- Laboratory of Medical Genetics, Center for Birth Defect Research and Prevention, Shenzhen Research Institute of Population and Family Planning, Shenzhen City, People's Republic of China
| | - Heyun Wang
- Laboratory of Medical Genetics, Center for Birth Defect Research and Prevention, Shenzhen Research Institute of Population and Family Planning, Shenzhen City, People's Republic of China
| | - Linghua Zhang
- Laboratory of Medical Genetics, Center for Birth Defect Research and Prevention, Shenzhen Research Institute of Population and Family Planning, Shenzhen City, People's Republic of China
| | - Hao Shao
- Laboratory of Medical Genetics, Center for Birth Defect Research and Prevention, Shenzhen Research Institute of Population and Family Planning, Shenzhen City, People's Republic of China
| | - Wenxu Hong
- Laboratory of Medical Genetics, Center for Birth Defect Research and Prevention, Shenzhen Research Institute of Population and Family Planning, Shenzhen City, People's Republic of China
| | - Lijie Zhang
- College of Pharmacy, Nankai University, Tianjin City, People's Republic of China
| | - Shan Duan
- Laboratory of Medical Genetics, Center for Birth Defect Research and Prevention, Shenzhen Research Institute of Population and Family Planning, Shenzhen City, People's Republic of China
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21
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Pylypenko O, Hammich H, Yu IM, Houdusse A. Rab GTPases and their interacting protein partners: Structural insights into Rab functional diversity. Small GTPases 2017. [PMID: 28632484 PMCID: PMC5902227 DOI: 10.1080/21541248.2017.1336191] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Rab molecular switches are key players in defining membrane identity and regulating intracellular trafficking events in eukaryotic cells. In spite of their global structural similarity, Rab-family members acquired particular features that allow them to perform specific cellular functions. The overall fold and local sequence conservations enable them to utilize a common machinery for prenylation and recycling; while individual Rab structural differences determine interactions with specific partners such as GEFs, GAPs and effector proteins. These interactions orchestrate the spatiotemporal regulation of Rab localization and their turning ON and OFF, leading to tightly controlled Rab-specific functionalities such as membrane composition modifications, recruitment of molecular motors for intracellular trafficking, or recruitment of scaffold proteins that mediate interactions with downstream partners, as well as actin cytoskeleton regulation. In this review we summarize structural information on Rab GTPases and their complexes with protein partners in the context of partner binding specificity and functional outcomes of their interactions in the cell.
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Affiliation(s)
- Olena Pylypenko
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
| | - Hussein Hammich
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France.,b Sorbonne Universités , UPMC Univ Paris 06, Sorbonne Universités, IFD , Paris , France
| | - I-Mei Yu
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
| | - Anne Houdusse
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
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22
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Oncogenic role of rab escort protein 1 through EGFR and STAT3 pathway. Cell Death Dis 2017; 8:e2621. [PMID: 28230863 PMCID: PMC5386492 DOI: 10.1038/cddis.2017.50] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 12/29/2016] [Accepted: 01/03/2017] [Indexed: 12/20/2022]
Abstract
Rab escort protein-1 (REP1) is linked to choroideremia (CHM), an X-linked degenerative disorder caused by mutations of the gene encoding REP1 (CHM). REP1 mutant zebrafish showed excessive cell death throughout the body, including the eyes, indicating that REP1 is critical for cell survival, a hallmark of cancer. In the present study, we found that REP1 is overexpressed in human tumor tissues from cervical, lung, and colorectal cancer patients, whereas it is expressed at relatively low levels in the normal tissue counterparts. REP1 expression was also elevated in A549 lung cancer cells and HT-29 colon cancer cells compared with BEAS-2B normal lung and CCD-18Co normal colon epithelial cells, respectively. Interestingly, short interfering RNA (siRNA)-mediated REP1 knockdown-induced growth inhibition of cancer cell lines via downregulation of EGFR and inactivation of STAT3, but had a negligible effect on normal cell lines. Moreover, overexpression of REP1 in BEAS-2B cells enhanced cell growth and anchorage-independent colony formation with little increase in EGFR level and STAT3 activation. Furthermore, REP1 knockdown effectively reduced tumor growth in a mouse xenograft model via EGFR downregulation and STAT3 inactivation in vivo. These data suggest that REP1 plays an oncogenic role, driving tumorigenicity via EGFR and STAT3 signaling, and is a potential therapeutic target to control cancers.
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23
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Shanmugam SK, Kumar K, Singh PK, Rastogi R, Mukhopadhyay A. Single GDP-dissociation Inhibitor Protein regulates endocytic and secretory pathways in Leishmania. Sci Rep 2016; 6:37058. [PMID: 27841328 PMCID: PMC5107955 DOI: 10.1038/srep37058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 10/07/2016] [Indexed: 11/09/2022] Open
Abstract
The role of GDP dissociation inhibitor (GDI) protein in regulation of Rab cycle in Leishmania is not known. Here, we have cloned and characterized the functions of GDI homologue in vivo in Leishmania. Our results have shown that LdGDI:WT along with GDP removes the Rab5 from purified endosomes and inhibits the homotypic fusion between early endosomes. Whereas, LdGDI:R239A, a dominant negative mutant of GDI, under the same condition neither removes the Rab5 from endosome nor inhibits fusion. To determine the role of Ld-GDI in vivo, transgenic parasites overexpressing GFP-LdGDI:WT or GFP-LdGDI:R239A, are co-expressed with RFP-LdRab5:WT, RFP-LdRab7:WT or RFP-LdRab1:WT. Our results have shown that overexpression of GFP-LdGDI:WT extracts the RFP-LdRab5, RFP-LdRab7 or RFP-LdRab1 from their discrete endomembrane predominantly into cytosol. No change in the distribution of indicated Rabs is detected with overexpression of GFP-LdGDI:R239A. To determine the functional significance, we have used hemoglobin as an endocytic marker and gp63 as a marker for secretory pathway. We have found that overexpression of GFP-LdGDI:WT enhances the lysosomal targeting of internalized hemoglobin and the secretion of gp63 in the parasites possibly by triggering Rab cycle. This is the first demonstration of a single GDI ubiquitously regulating both endocytic and secretory pathways in Leishmania.
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Affiliation(s)
| | - Kamal Kumar
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Pawan Kishor Singh
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Ruchir Rastogi
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi 110067, India
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Simunovic MP, Jolly JK, Xue K, Edwards TL, Groppe M, Downes SM, MacLaren RE. The Spectrum of CHM Gene Mutations in Choroideremia and Their Relationship to Clinical Phenotype. Invest Ophthalmol Vis Sci 2016; 57:6033-6039. [PMID: 27820636 PMCID: PMC5102569 DOI: 10.1167/iovs.16-20230] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 09/22/2016] [Indexed: 01/17/2023] Open
Abstract
PURPOSE We report the underlying genotype and explore possible genotypic-phenotypic correlations in a large cohort of choroideremia patients. METHODS We studied prospectively a cohort of 79 patients diagnosed within a tertiary referral service for patients with retinal dystrophies. Phenotypic evaluation consisted of clinical examination, including visual acuity and residual retinal area by fundus autofluorescence (FAF). Genotype was established by sequencing. We also investigated whether particular genotypes were associated with more severe phenotypes by performing analysis of covariance (ANCOVA), with visual acuity and FAF as the dependent variables and age as the covariant. RESULTS A total of 74 (94%) of patients in our cohort had causative mutations by sequencing, the majority of which were anticipated to be null. Of these, 35 (47%) had insertions and deletions, 13 (18%) had mutations predicted to affect splicing, and 26 (35%) had single point mutations. In the latter case, 13 of 21 (62%) pedigrees with single point mutations were C to T transitions at C-phosphate-G (CpG) dinucleotides. These mutations were spread across 5 of only 24 CpG dinucleotides in the entire CHM cDNA. Furthermore, these 5 locations are the only sites at which C to T transitions result in a stop codon. No clear evidence was found for genotype-phenotype correlation except in the instance of a patient with a large deletion involving neighbouring sequences. CONCLUSIONS In patients with a diagnosis of choroideremia made by a specialty service, there is a high likelihood of establishing a genetic diagnosis. The majority of causative mutations appear to be null and, therefore, may benefit from gene replacement therapy. A disproportionate number of single point mutations observed were C to T transitions, consistent with the evolutionary decay of CpG dinucleotides through methylation and subsequent deamination. Hence, the development of choroideremia in such patients may represent the unwanted consequence of human evolution; de novo mutations are predicted to arise at these sites in future generations. (ClinicalTrials.gov number, NCT01461213.).
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Affiliation(s)
- Matthew P. Simunovic
- Nuffield Laboratory of Ophthalmology, University of Oxford West Wing, John Radcliffe Hospital, Oxford, United Kingdom
- Oxford Eye Hospital, University of Oxford NHS Trust, West Wing, John Radcliffe Hospital, Oxford, United Kingdom
- Save Sight Institute, Sydney University, Sydney, New South Wales, Australia
- Sydney Eye Hospital, Sydney, New South Wales, Australia
| | - Jasleen K. Jolly
- Nuffield Laboratory of Ophthalmology, University of Oxford West Wing, John Radcliffe Hospital, Oxford, United Kingdom
- Oxford Eye Hospital, University of Oxford NHS Trust, West Wing, John Radcliffe Hospital, Oxford, United Kingdom
| | - Kanmin Xue
- Nuffield Laboratory of Ophthalmology, University of Oxford West Wing, John Radcliffe Hospital, Oxford, United Kingdom
- Oxford Eye Hospital, University of Oxford NHS Trust, West Wing, John Radcliffe Hospital, Oxford, United Kingdom
| | - Thomas L. Edwards
- Nuffield Laboratory of Ophthalmology, University of Oxford West Wing, John Radcliffe Hospital, Oxford, United Kingdom
- Oxford Eye Hospital, University of Oxford NHS Trust, West Wing, John Radcliffe Hospital, Oxford, United Kingdom
| | - Markus Groppe
- Nuffield Laboratory of Ophthalmology, University of Oxford West Wing, John Radcliffe Hospital, Oxford, United Kingdom
- Oxford Eye Hospital, University of Oxford NHS Trust, West Wing, John Radcliffe Hospital, Oxford, United Kingdom
| | - Susan M. Downes
- Nuffield Laboratory of Ophthalmology, University of Oxford West Wing, John Radcliffe Hospital, Oxford, United Kingdom
- Oxford Eye Hospital, University of Oxford NHS Trust, West Wing, John Radcliffe Hospital, Oxford, United Kingdom
| | - Robert E. MacLaren
- Nuffield Laboratory of Ophthalmology, University of Oxford West Wing, John Radcliffe Hospital, Oxford, United Kingdom
- Oxford Eye Hospital, University of Oxford NHS Trust, West Wing, John Radcliffe Hospital, Oxford, United Kingdom
- Moorfields Eye Hospital, London, United Kingdom
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Gavriljuk K, Schartner J, Seidel H, Dickhut C, Zahedi RP, Hedberg C, Kötting C, Gerwert K. Unraveling the Phosphocholination Mechanism of the Legionella pneumophila Enzyme AnkX. Biochemistry 2016; 55:4375-85. [PMID: 27404583 DOI: 10.1021/acs.biochem.6b00524] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The intracellular pathogen Legionella pneumophila infects lung macrophages and injects numerous effector proteins into the host cell to establish a vacuole for proliferation. The necessary interference with vesicular trafficking of the host is achieved by modulation of the function of Rab GTPases. The effector protein AnkX chemically modifies Rab1b and Rab35 by covalent phosphocholination of serine or threonine residues using CDP-choline as a donor. So far, the phosphoryl transfer mechanism and the relevance of observed autophosphocholination of AnkX remained disputable. We designed tailored caged compounds to make this type of enzymatic reaction accessible for time-resolved Fourier transform infrared difference spectroscopy. By combining spectroscopic and biochemical methods, we determined that full length AnkX is autophosphocholinated at Ser521, Thr620, and Thr943. However, autophosphocholination loses specificity for these sites in shortened constructs and does not appear to be relevant for the catalysis of the phosphoryl transfer. In contrast, transient phosphocholination of His229 in the conserved catalytic motif might exist as a short-lived reaction intermediate. Upon substrate binding, His229 is deprotonated and locked in this state, being rendered capable of a nucleophilic attack on the pyrophosphate moiety of the substrate. The proton that originated from His229 is transferred to a nearby carboxylic acid residue. Thus, our combined findings support a ping-pong mechanism involving phosphocholination of His229 and subsequent transfer of phosphocholine to the Rab GTPase. Our approach can be extended to the investigation of further nucleotidyl transfer reactions, which are currently of reemerging interest in regulatory pathways of host-pathogen interactions.
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Affiliation(s)
- Konstantin Gavriljuk
- Department of Biophysics, Ruhr-Universität Bochum , Universitätsstrasse 150, 44801 Bochum, Germany
| | - Jonas Schartner
- Department of Biophysics, Ruhr-Universität Bochum , Universitätsstrasse 150, 44801 Bochum, Germany
| | - Hans Seidel
- Department of Biophysics, Ruhr-Universität Bochum , Universitätsstrasse 150, 44801 Bochum, Germany
| | - Clarissa Dickhut
- Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V. , Otto-Hahn-Strasse 6b, 44227 Dortmund, Germany
| | - Rene P Zahedi
- Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V. , Otto-Hahn-Strasse 6b, 44227 Dortmund, Germany
| | - Christian Hedberg
- Department of Chemistry and Umeå Center for Microbial Research, Umeå University , SE-90187 Umeå, Sweden
| | - Carsten Kötting
- Department of Biophysics, Ruhr-Universität Bochum , Universitätsstrasse 150, 44801 Bochum, Germany
| | - Klaus Gerwert
- Department of Biophysics, Ruhr-Universität Bochum , Universitätsstrasse 150, 44801 Bochum, Germany
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Shelby SJ, Feathers KL, Ganios AM, Jia L, Miller JM, Thompson DA. MERTK signaling in the retinal pigment epithelium regulates the tyrosine phosphorylation of GDP dissociation inhibitor alpha from the GDI/CHM family of RAB GTPase effectors. Exp Eye Res 2015; 140:28-40. [PMID: 26283020 DOI: 10.1016/j.exer.2015.08.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 08/10/2015] [Accepted: 08/10/2015] [Indexed: 10/25/2022]
Abstract
Photoreceptor outer segments (OS) in the vertebrate retina undergo a process of continual renewal involving shedding of disc membranes that are cleared by phagocytic uptake into the retinal pigment epithelium (RPE). In dystrophic Royal College of Surgeons (RCS) rats, OS phagocytosis is blocked by a mutation in the gene encoding the receptor tyrosine kinase MERTK. To identify proteins tyrosine-phosphorylated downstream of MERTK in the RPE, MALDI-mass spectrometry with peptide-mass fingerprinting was used in comparative studies of RCS congenic and dystrophic rats. At times corresponding to peak phagocytic activity, the RAB GTPase effector GDP dissociation inhibitor alpha (GDI1) was found to undergo tyrosine phosphorylation only in congenic rats. In cryosections of native RPE/choroid, GDI1 colocalized with MERTK and the intracellular tyrosine-kinase SRC. In cultured RPE-J cells, and in transfected heterologous cells, MERTK stimulated SRC-mediated tyrosine phosphorylation of GDI1. In OS-fed RPE-J cells, GDI1 colocalized with MERTK and SRC on apparent phagosomes located near the apical membrane. In addition, both GDI1 and RAB5, a regulator of vesicular transport, colocalized with ingested OS. Taken together, these findings identify a novel role of MERTK signaling in membrane trafficking in the RPE that is likely to subserve mechanisms of phagosome formation.
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Affiliation(s)
- Shameka J Shelby
- Department of Biological Chemistry, University of Michigan Medical School, 1150 W. Medical Center Dr., Ann Arbor, MI 48109, USA; Department of Ophthalmology and Visual Sciences, University of Michigan Medical School, 1000 Wall St., Ann Arbor, MI 48105, USA
| | - Kecia L Feathers
- Department of Ophthalmology and Visual Sciences, University of Michigan Medical School, 1000 Wall St., Ann Arbor, MI 48105, USA
| | - Anna M Ganios
- Department of Biological Chemistry, University of Michigan Medical School, 1150 W. Medical Center Dr., Ann Arbor, MI 48109, USA
| | - Lin Jia
- Department of Ophthalmology and Visual Sciences, University of Michigan Medical School, 1000 Wall St., Ann Arbor, MI 48105, USA
| | - Jason M Miller
- Department of Ophthalmology and Visual Sciences, University of Michigan Medical School, 1000 Wall St., Ann Arbor, MI 48105, USA
| | - Debra A Thompson
- Department of Biological Chemistry, University of Michigan Medical School, 1150 W. Medical Center Dr., Ann Arbor, MI 48109, USA; Department of Ophthalmology and Visual Sciences, University of Michigan Medical School, 1000 Wall St., Ann Arbor, MI 48105, USA.
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RabGDIα is a negative regulator of interferon-γ-inducible GTPase-dependent cell-autonomous immunity to Toxoplasma gondii. Proc Natl Acad Sci U S A 2015; 112:E4581-90. [PMID: 26240314 DOI: 10.1073/pnas.1510031112] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
IFN-γ orchestrates cell-autonomous host defense against various intracellular vacuolar pathogens. IFN-γ-inducible GTPases, such as p47 immunity-related GTPases (IRGs) and p65 guanylate-binding proteins (GBPs), are recruited to pathogen-containing vacuoles, which is important for disruption of the vacuoles, culminating in the cell-autonomous clearance. Although the positive regulation for the proper recruitment of IRGs and GBPs to the vacuoles has been elucidated, the suppressive mechanism is unclear. Here, we show that Rab GDP dissociation inhibitor α (RabGDIα), originally identified as a Rab small GTPase inhibitor, is a negative regulator of IFN-γ-inducible GTPases in cell-autonomous immunity to the intracellular pathogen Toxoplasma gondii. Overexpression of RabGDIα, but not of RabGDIβ, impaired IFN-γ-dependent reduction of T. gondii numbers. Conversely, RabGDIα deletion in macrophages and fibroblasts enhanced the IFN-γ-induced clearance of T. gondii. Furthermore, upon a high dose of infection by T. gondii, RabGDIα-deficient mice exhibited a decreased parasite burden in the brain and increased resistance in the chronic phase than did control mice. Among members of IRGs and GBPs important for the parasite clearance, Irga6 and Gbp2 alone were more frequently recruited to T. gondii-forming parasitophorous vacuoles in RabGDIα-deficient cells. Notably, Gbp2 positively controlled Irga6 recruitment that was inhibited by direct and specific interactions of RabGDIα with Gbp2 through the lipid-binding pocket. Taken together, our results suggest that RabGDIα inhibits host defense against T. gondii by negatively regulating the Gbp2-Irga6 axis of IFN-γ-dependent cell-autonomous immunity.
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Gavriljuk K, Schartner J, Itzen A, Goody RS, Gerwert K, Kötting C. Reaction mechanism of adenylyltransferase DrrA from Legionella pneumophila elucidated by time-resolved fourier transform infrared spectroscopy. J Am Chem Soc 2014; 136:9338-45. [PMID: 24950229 DOI: 10.1021/ja501496d] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Modulation of the function of small GTPases that regulate vesicular trafficking is a strategy employed by several human pathogens. Legionella pneumophila infects lung macrophages and injects a plethora of different proteins into its host cell. Among these is DrrA/SidM, which catalyzes stable adenylylation of Rab1b, a regulator of endoplasmatic reticulum to Golgi trafficking, and thereby alters the function and interactions of this small GTPase. We employed time-resolved FTIR-spectroscopy to monitor the DrrA-catalyzed AMP-transfer to Tyr77 of Rab1b. A transient complex between DrrA, adenylylated Rab1b, and the pyrophosphate byproduct was resolved, allowing us to analyze the interactions at the active site. Combination of isotopic labeling and site-directed mutagenesis allowed us to derive the catalytic mechanism of DrrA from the FTIR difference spectra. DrrA shares crucial residues in the ATP-binding pocket with similar AMP-transferring enzymes such as glutamine synthetase adenylyltransferase or kanamycin nucleotidyltransferase, but provides the complete active site on a single subunit. We determined that Asp112 of DrrA functions as the catalytic base for deprotonation of Tyr77 of Rab1b to enable nucleophilic attack on the ATP. The study provides detailed understanding of the Legionella pneumophila protein DrrA and of AMP-transfer reactions in general.
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Affiliation(s)
- Konstantin Gavriljuk
- Department of Biophysics, Ruhr-Universität Bochum , Universitätsstrasse 150, 44801 Bochum, Germany
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30
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Afshordel S, Wood WG, Igbavboa U, Muller WE, Eckert GP. Impaired geranylgeranyltransferase-I regulation reduces membrane-associated Rho protein levels in aged mouse brain. J Neurochem 2014; 129:732-42. [PMID: 24428713 PMCID: PMC3999261 DOI: 10.1111/jnc.12654] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 01/09/2014] [Accepted: 01/10/2014] [Indexed: 12/21/2022]
Abstract
Synaptic impairment rather than neuronal loss may be the leading cause of cognitive dysfunction in brain aging. Certain small Rho-GTPases are involved in synaptic plasticity, and their dysfunction is associated with brain aging and neurodegeneration. Rho-GTPases undergo prenylation by attachment of geranylgeranylpyrophosphate (GGPP) catalyzed by GGTase-I. We examined age-related changes in the abundance of Rho and Rab proteins in membrane and cytosolic fractions as well as of GGTase-I in brain tissue of 3- and 23-month-old C57BL/6 mice. We report a shift in the cellular localization of Rho-GTPases toward reduced levels of membrane-associated and enhanced cytosolic levels of those proteins in aged mouse brain as compared with younger mice. The age-related reduction in membrane-associated Rho proteins was associated with a reduction in GGTase-Iβ levels that regulates binding of GGPP to Rho-GTPases. Proteins prenylated by GGTase-II were not reduced in aged brain indicating a specific targeting of GGTase-I in the aged brain. Inhibition of GGTase-I in vitro modeled the effects of aging we observed in vivo. We demonstrate for the first time a decrease in membrane-associated Rho proteins in aged brain in association with down-regulation of GGTase-Iβ. This down-regulation could be one of the mechanisms causing age-related weakening of synaptic plasticity.
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Affiliation(s)
- Sarah Afshordel
- Department of Pharmacology, Biocenter Niederursel, University of Frankfurt, Max-von-Laue-St. 9, 60438 Frankfurt, Germany
| | - W. Gibson Wood
- Department of Pharmacology, University of Minnesota School of Medicine, Geriatric Research, Education and Clinical Center, VAMC, Minneapolis, MN 55417 USA
| | - Urule Igbavboa
- Department of Pharmacology, University of Minnesota School of Medicine, Geriatric Research, Education and Clinical Center, VAMC, Minneapolis, MN 55417 USA
| | - Walter E. Muller
- Department of Pharmacology, Biocenter Niederursel, University of Frankfurt, Max-von-Laue-St. 9, 60438 Frankfurt, Germany
| | - Gunter P. Eckert
- Department of Pharmacology, Biocenter Niederursel, University of Frankfurt, Max-von-Laue-St. 9, 60438 Frankfurt, Germany
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Köhnke M, Delon C, Hastie ML, Nguyen UTT, Wu YW, Waldmann H, Goody RS, Gorman JJ, Alexandrov K. Rab GTPase prenylation hierarchy and its potential role in choroideremia disease. PLoS One 2013; 8:e81758. [PMID: 24358126 PMCID: PMC3864799 DOI: 10.1371/journal.pone.0081758] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2013] [Accepted: 10/16/2013] [Indexed: 11/29/2022] Open
Abstract
Protein prenylation is a widespread post-translational modification in eukaryotes that plays a crucial role in membrane targeting and signal transduction. RabGTPases is the largest group of post-translationally C-terminally geranylgeranylated. All Rabs are processed by Rab geranylgeranyl-transferase and Rab escort protein (REP). Human genetic defects resulting in the loss one of two REP isoforms REP-1, lead to underprenylation of RabGTPases that manifests in retinal degradation and blindness known as choroideremia. In this study we used a combination of microinjections and chemo-enzymatic tagging to establish whether Rab GTPases are prenylated and delivered to their target cellular membranes with the same rate. We demonstrate that although all tested Rab GTPases display the same rate of membrane delivery, the extent of Rab prenylation in 5 hour time window vary by more than an order of magnitude. We found that Rab27a, Rab27b, Rab38 and Rab42 display the slowest prenylation in vivo and in the cell. Our work points to possible contribution of Rab38 to the emergence of choroideremia in addition to Rab27a and Rab27b.
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Affiliation(s)
- Monika Köhnke
- Department of Cell and Molecular Biology, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Queensland, Australia
| | - Christine Delon
- Department of Physical Biochemistry, Max-Planck-Institute for Molecular Physiology, Dortmund, Germany
| | - Marcus L. Hastie
- Queensland Berghofer Medical Research Institute, PO Royal Brisbane Hospital, Herston, Queensland, Australia
| | - Uyen T. T. Nguyen
- Department of Cell and Molecular Biology, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Queensland, Australia
| | - Yao-Wen Wu
- Department of Physical Biochemistry, Max-Planck-Institute for Molecular Physiology, Dortmund, Germany
| | - Herbert Waldmann
- Department of Chemical Biology, Max-Planck-Institute for Molecular Physiology, Dortmund, Germany
| | - Roger S. Goody
- Department of Physical Biochemistry, Max-Planck-Institute for Molecular Physiology, Dortmund, Germany
| | - Jeffrey J. Gorman
- Queensland Berghofer Medical Research Institute, PO Royal Brisbane Hospital, Herston, Queensland, Australia
| | - Kirill Alexandrov
- Department of Cell and Molecular Biology, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Queensland, Australia
- * E-mail:
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Membrane extraction of Rab proteins by GDP dissociation inhibitor characterized using attenuated total reflection infrared spectroscopy. Proc Natl Acad Sci U S A 2013; 110:13380-5. [PMID: 23898197 DOI: 10.1073/pnas.1307655110] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Membrane trafficking is regulated by small Ras-like GDP/GTP binding proteins of the Rab subfamily (Rab GTPases) that cycle between membranes and cytosol depending on their nucleotide state. The GDP dissociation inhibitor (GDI) solubilizes prenylated Rab GTPases from and shuttles them between membranes in the form of a soluble cytosolic complex. We use attenuated total reflection-Fourier transform infrared spectroscopy to directly observe extraction of Rab GTPases from model membranes by GDI. In their native form, most Rab GTPases are doubly geranylgeranylated at the C terminus to achieve localization to the membrane. We find that monogeranylgeranylated Rab35 and Rab1b reversibly bind to a negatively charged model membrane. Correct folding and GTPase activity of the membrane-bound protein can be evaluated. The dissociation kinetics depends on the C-terminal sequence and charge of the GTPases. The attenuated total reflection experiments show that GDI genuinely accelerates the intrinsic Rab membrane dissociation. The extraction process is characterized and occurs in a nucleotide-dependent manner. Furthermore, we find that phosphocholination of Rab35, which is catalyzed by the Legionella pneumophila protein AnkX, interferes with the ability of GDI to extract Rab35 from the membrane. The attenuated total reflection-Fourier transform infrared spectroscopy approach enables label-free investigation of the interaction between GDI and Rab GTPases in a membrane environment. Thereby, GDI is revealed to actively extract monogeranylgeranylated membrane-bound Rab GTPases and, thus, is not merely a solubilization factor.
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Seixas E, Barros M, Seabra MC, Barral DC. Rab and Arf proteins in genetic diseases. Traffic 2013; 14:871-85. [PMID: 23565987 DOI: 10.1111/tra.12072] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2012] [Revised: 04/03/2013] [Accepted: 04/08/2013] [Indexed: 01/29/2023]
Abstract
Rab and ADP-ribosylation factor (Arf) family proteins are master regulators of membrane trafficking and are involved in all steps of vesicular transport. These families of small guanine-nucleotide-binding (G) proteins are well suited to regulate membrane trafficking processes since their nucleotide state determines their conformation and the capacity to bind to a multitude of effectors, which mediate their functions. In recent years, several inherited diseases have been associated with mutations in genes encoding proteins belonging to these two families or in proteins that regulate their GTP-binding cycle. The genetic diseases that are caused by defects in Rabs, Arfs or their regulatory proteins are heterogeneous and display diverse symptoms. However, these diseases mainly affect two types of subcellular compartments, namely lysosome-related organelles and cilia. Also, several of these diseases affect the nervous system. Thus, the study of these diseases represents an opportunity to understand their etiology and the molecular mechanisms involved, as well as to develop novel therapeutic strategies.
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Affiliation(s)
- Elsa Seixas
- CEDOC, Faculdade de Ciências Médicas, FCM, Universidade Nova de Lisboa, 1169-056, Lisboa, Portugal
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Boye SE, Boye SL, Lewin AS, Hauswirth WW. A comprehensive review of retinal gene therapy. Mol Ther 2013; 21:509-19. [PMID: 23358189 DOI: 10.1038/mt.2012.280] [Citation(s) in RCA: 204] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Blindness, although not life threatening, is a debilitating disorder for which few, if any treatments exist. Ocular gene therapies have the potential to profoundly improve the quality of life in patients with inherited retinal disease. As such, tremendous focus has been given to develop such therapies. Several factors make the eye an ideal organ for gene-replacement therapy including its accessibility, immune privilege, small size, compartmentalization, and the existence of a contralateral control. This review will provide a comprehensive summary of (i) existing gene therapy clinical trials for several genetic forms of blindness and (ii) preclinical efficacy and safety studies in a variety of animal models of retinal disease which demonstrate strong potential for clinical application. To be as comprehensive as possible, we include additional proof of concept studies using gene replacement, neurotrophic/neuroprotective, optogenetic, antiangiogenic, or antioxidative stress strategies as well as a description of the current challenges and future directions in the ocular gene therapy field to this review as a supplement.
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Affiliation(s)
- Shannon E Boye
- Department of Ophthalmology, University of Florida, Gainesville, FL, USA.
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Dickison VM, Richmond AM, Abu Irqeba A, Martak JG, Hoge SCE, Brooks MJ, Othman MI, Khanna R, Mears AJ, Chowdhury AY, Swaroop A, Ogilvie JM. A role for prenylated rab acceptor 1 in vertebrate photoreceptor development. BMC Neurosci 2012; 13:152. [PMID: 23241222 PMCID: PMC3576285 DOI: 10.1186/1471-2202-13-152] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Accepted: 11/19/2012] [Indexed: 11/10/2022] Open
Abstract
Background The rd1 mouse retina is a well-studied model of retinal degeneration where rod photoreceptors undergo cell death beginning at postnatal day (P) 10 until P21. This period coincides with photoreceptor terminal differentiation in a normal retina. We have used the rd1 retina as a model to investigate early molecular defects in developing rod photoreceptors prior to the onset of degeneration. Results Using a microarray approach, we performed gene profiling comparing rd1 and wild type (wt) retinas at four time points starting at P2, prior to any obvious biochemical or morphological differences, and concluding at P8, prior to the initiation of cell death. Of the 143 identified differentially expressed genes, we focused on Rab acceptor 1 (Rabac1), which codes for the protein Prenylated rab acceptor 1 (PRA1) and plays an important role in vesicular trafficking. Quantitative RT-PCR analysis confirmed reduced expression of PRA1 in rd1 retina at all time points examined. Immunohistochemical observation showed that PRA1-like immunoreactivity (LIR) co-localized with the cis-Golgi marker GM-130 in the photoreceptor as the Golgi translocated from the perikarya to the inner segment during photoreceptor differentiation in wt retinas. Diffuse PRA1-LIR, distinct from the Golgi marker, was seen in the distal inner segment of wt photoreceptors starting at P8. Both plexiform layers contained PRA1 positive punctae independent of GM-130 staining during postnatal development. In the inner retina, PRA1-LIR also colocalized with the Golgi marker in the perinuclear region of most cells. A similar pattern was seen in the rd1 mouse inner retina. However, punctate and significantly reduced PRA1-LIR was present throughout the developing rd1 inner segment, consistent with delayed photoreceptor development and abnormalities in Golgi sorting and vesicular trafficking. Conclusions We have identified genes that are differentially regulated in the rd1 retina at early time points, which may give insights into developmental defects that precede photoreceptor cell death. This is the first report of PRA1 expression in the retina. Our data support the hypothesis that PRA1 plays an important role in vesicular trafficking between the Golgi and cilia in differentiating and mature rod photoreceptors.
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Huang AS, Kim LA, Fawzi AA. Clinical characteristics of a large choroideremia pedigree carrying a novel CHM mutation. ACTA ACUST UNITED AC 2012; 130:1184-9. [PMID: 22965595 DOI: 10.1001/archophthalmol.2012.1117] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To describe a large family with a novel mutation in CHM. METHODS Family members were characterized using clinical examination, wide-field fundus photography, wide-field autofluorescence, and spectral domain optical coherence tomography. The CHM mutation was identified with the National Institutes of Health-sponsored eyeGene program. RESULTS A novel nonsense CHM mutation (T1194G), resulting in a premature stop (Y398X) and loss of the final one-third C-terminal portion of the protein, was identified. A large pedigree was generated from information provided by the twice-married proband. Seven men (aged 27-39 years) and 7 women (aged 22-89 years) were evaluated. Affected men showed characteristic peripheral chorioretinal atrophy with islands of macular sparing. Female carriers exhibited a wide range of variability, from mild pigmentary alterations to significant chorioretinal atrophy with severe vision loss. Older women tended to have a more severe phenotype. Autofluorescence demonstrating subfoveal loss or absence of retinal pigment epithelium correlated with vision loss in both sexes. Spectral domain optical coherence tomography demonstrated dynamic changes and remodeling of the outer retina over time, including focal thickening, drusenlike deposits, and disruption to photoreceptor inner segment and outer segment junctions in young female carriers. CONCLUSIONS CHM (T1194G) is a novel mutation that manifests a wide range of phenotypic variability in a single family with a trend toward more severe phenotypes in older female carriers. Our findings emphasize the importance of considering X-linked diseases by carefully evaluating pedigrees in women with severe manifestations of disease. CLINICAL RELEVANCE These findings demonstrate a novel CHM mutation that emphasizes severe posterior pole carrier phenotypes, age-related changes, and early choroideremia disease.
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Affiliation(s)
- Alex S Huang
- Doheny Eye Institute, Department of Ophthalmology, Keck School of Medicine of the University of Southern California, Los Angeles, USA
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Gutkowska M, Swiezewska E. Structure, regulation and cellular functions of Rab geranylgeranyl transferase and its cellular partner Rab Escort Protein. Mol Membr Biol 2012; 29:243-56. [DOI: 10.3109/09687688.2012.693211] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Liu S, Storrie B. Are Rab proteins the link between Golgi organization and membrane trafficking? Cell Mol Life Sci 2012; 69:4093-106. [PMID: 22581368 DOI: 10.1007/s00018-012-1021-6] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Revised: 04/18/2012] [Accepted: 04/24/2012] [Indexed: 11/25/2022]
Abstract
The fundamental separation of Golgi function between subcompartments termed cisternae is conserved across all eukaryotes. Likewise, Rab proteins, small GTPases of the Ras superfamily, are putative common coordinators of Golgi organization and protein transport. However, despite sequence conservation, e.g., Rab6 and Ypt6 are conserved proteins between humans and yeast, the fundamental organization of the organelle can vary profoundly. In the yeast Saccharomyces cerevisiae, the Golgi cisternae are physically separated from one another, while in mammalian cells, the cisternae are stacked one upon the other. Moreover, in mammalian cells, many Golgi stacks are typically linked together to generate a ribbon structure. Do evolutionarily conserved Rab proteins regulate secretory membrane trafficking and diverse Golgi organization in a common manner? In mammalian cells, some Golgi-associated Rab proteins function in coordination of protein transport and maintenance of Golgi organization. These include Rab6, Rab33B, Rab1, Rab2, Rab18, and Rab43. In yeast, these include Ypt1, Ypt32, and Ypt6. Here, based on evidence from both yeast and mammalian cells, we speculate on the essential role of Rab proteins in Golgi organization and protein transport.
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Affiliation(s)
- Shijie Liu
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
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Abstract
The causative agent of Legionnaires disease, Legionella pneumophila, injects several hundred proteins into the cell it infects, many of which interfere with or exploit vesicular transport processes. One of these proteins, LidA, has been described as a Rab effector (i.e., a molecule that interacts preferentially with the GTP-bound form of Rab). We describe here the structure and biochemistry of a complex between the Rab-binding domain of LidA and active Rab8a. LidA displays structural peculiarities in binding to Rab8a, forming a considerably extended interface in comparison to known mammalian Rab effectors, and involving regions of the GTPase that are not seen in other Rab:effector complexes. In keeping with this extended binding interface, which involves four α-helices and two pillar-like structures of LidA, the stability of LidA-Rab interactions is dramatically greater than for other such complexes. For Rab1b and Rab8a, these affinities are extraordinarily high, but for the more weakly bound Rab6a, K(d) values of 4 nM for the inactive and 30 pM for the active form were found. Rab1b and Rab8a appear to bind LidA with K(d) values in the low picomolar range, making LidA a Rab supereffector.
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Vázquez-Martínez R, Malagón MM. Rab proteins and the secretory pathway: the case of rab18 in neuroendocrine cells. Front Endocrinol (Lausanne) 2011; 2:1. [PMID: 22649356 PMCID: PMC3355916 DOI: 10.3389/fendo.2011.00001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2010] [Accepted: 01/03/2011] [Indexed: 11/21/2022] Open
Abstract
The secretory pathway is a process characteristic of cells specialized in secretion such as endocrine cells and neurons. It consists of different stages that are dependent on specific transport of proteins in vesicular-tubular carriers. Biochemical analyses have unveiled a number of protein families that confer identity to carrier vesicles and specificity to their transport. Among them is the family of Rab proteins, Ras-like small GTPases that anchor to the surface of transport vesicles and participate in vesicle formation from the donor compartment, transport along cytoskeletal tracks, and docking and fusion with the acceptor compartment. All of these functions are accomplished through the recruitment of effector proteins, such as sorting adaptors, tethering factors, kinases, phosphatases, and motors. The numerous Rab proteins have distinct subcellular distributions throughout the endomembrane system, which ensures efficient cargo transfer. Rab proteins act as molecular switches that alternate between a cytosolic GDP-bound, inactive form and a membrane-associated GTP-bound, active conformation. Cycling between inactive and active states is a highly regulated process that enables Rabs to confer spatio-temporal precision to the different stages through which a vesicle passes during its lifespan. This review focuses on our current knowledge on Rab functioning, from their structural features to the multiple regulatory proteins and effectors that control Rab activity and translate Rab function. Furthermore, we also summarize the information available on a particular Rab protein, Rab18, which has been linked to the control of secretory granule traffic in neuroendocrine cells.
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Affiliation(s)
- Rafael Vázquez-Martínez
- Department of Cell Biology, Physiology and Immunology, University of CordobaCordoba, Spain
- Instituto Maimónides de Investigación Biomédica, Biomedical Research Center in Red Physiopathology of Obesity and NutritionCordoba, Spain
| | - Maria M. Malagón
- Department of Cell Biology, Physiology and Immunology, University of CordobaCordoba, Spain
- Instituto Maimónides de Investigación Biomédica, Biomedical Research Center in Red Physiopathology of Obesity and NutritionCordoba, Spain
- *Correspondence: Maria M. Malagón, Department of Cell Biology, Physiology and Immunology, Universidad de Córdoba, Campus de Rabanales, Edificio Severo-Ochoa, Planta 3, E-14014 Córdoba, Spain. e-mail:
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Mitra S, Cheng KW, Mills GB. Rab GTPases implicated in inherited and acquired disorders. Semin Cell Dev Biol 2010; 22:57-68. [PMID: 21147240 DOI: 10.1016/j.semcdb.2010.12.005] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Revised: 12/06/2010] [Accepted: 12/06/2010] [Indexed: 01/05/2023]
Abstract
The endocytotic machinery imports, transports and exports receptors and associated molecules between the plasma membrane and various cytoplasmic chambers resulting in selective recycling, degradation, or secretion of molecules and signaling complexes. Trafficking of receptors, growth factors, nutrients, cytokines, integrins as well as pathogens dictates the kinetics and magnitude of signal transduction cascades. Understandably, alterations in the 'fate' of such cargo complexes have profound physiologic and pathophysiologic implications. Rab GTPases regulate endocytosis by decorating intracellular vesicles and targeting these vesicles along with their cargoes to appropriate subcellular compartments. In the last decade, the number of genetic diseases driven by germline mutations in Rab GTPases or their interacting proteins, has increased and there is growing evidence of aberrant Rab GTPase function in acquired pathophysiologies such as immune deficiency, infection, obesity, diabetes and cancer.
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Affiliation(s)
- Shreya Mitra
- Department of Systems Biology, The University of Texas, MD Anderson Cancer Center, Houston, TX 77054-1942, USA.
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Wang X, Chang L, Sun Z, Zhang Y. Comparative Proteomic Analysis of Differentially Expressed Proteins in the Earthworm Eisenia fetida during Escherichia coli O157:H7 Stress. J Proteome Res 2010; 9:6547-60. [DOI: 10.1021/pr1007398] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Xing Wang
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, P. R. China, and The Anhui Provincial Key Laboratory of the Resource Plant Biology in School of Life Sciences, Huaibei Normal University, Huaibei, Anhui, P. R. China
| | - Li Chang
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, P. R. China, and The Anhui Provincial Key Laboratory of the Resource Plant Biology in School of Life Sciences, Huaibei Normal University, Huaibei, Anhui, P. R. China
| | - Zhenjun Sun
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, P. R. China, and The Anhui Provincial Key Laboratory of the Resource Plant Biology in School of Life Sciences, Huaibei Normal University, Huaibei, Anhui, P. R. China
| | - Yufeng Zhang
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, P. R. China, and The Anhui Provincial Key Laboratory of the Resource Plant Biology in School of Life Sciences, Huaibei Normal University, Huaibei, Anhui, P. R. China
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Kanno E, Ishibashi K, Kobayashi H, Matsui T, Ohbayashi N, Fukuda M. Comprehensive screening for novel rab-binding proteins by GST pull-down assay using 60 different mammalian Rabs. Traffic 2010; 11:491-507. [PMID: 20070612 DOI: 10.1111/j.1600-0854.2010.01038.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The Rab family belongs to the Ras-like small GTPase superfamily and is implicated in membrane trafficking through interaction with specific effector molecules. Because of the large number of Rab isoforms in mammals, however, the effectors of most of the mammalian Rabs are yet to be identified. In this study, we systematically screened five different cell or tissue lysates for novel Rab effectors by a combination of glutathione S-transferase (GST) pull-down assay with 60 different mammalian Rabs and mass spectroscopic analysis. Three of the 21 Rab-binding proteins we identified, mKIAA1055/TBC1D2B (Rab22-binding protein), GAPCenA/TBC1D11 (Rab36-binding protein) and centaurin beta2/ACAP2 (Rab35-binding protein), are GTPase-activating proteins (GAPs) for Rab or Arf. Although it has recently been proposed that the Rab-GAP (Tre-2 /Bub2/Cdc16) domain physically interacts with its substrate Rab, these three GAPs interacted with specific Rabs via a domain other than a GAP domain, e.g. centaurin beta2 binds GTP-Rab35 via the ankyrin repeat (ANKR) domain. Although centaurin beta2 did not exhibit any Rab35-GAP activity in vitro, the Rab35-binding ANKR domain of centaurin beta2 was found to be required for its plasma membrane localization and regulation of Rab35-dependent neurite outgrowth of PC12 cells through inactivation of Arf6. These findings suggest a novel mode of interaction between Rab and GAP.
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Affiliation(s)
- Eiko Kanno
- Laboratory of Membrane Trafficking Mechanisms, Department of Developmental Biology and Neurosciences, Graduate School of Life Sciences, Tohoku University, Aobayama, Aoba-ku, Sendai, Miyagi 980-8578, Japan
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Gordiyenko NV, Fariss RN, Zhi C, MacDonald IM. Silencing of the CHM gene alters phagocytic and secretory pathways in the retinal pigment epithelium. Invest Ophthalmol Vis Sci 2009; 51:1143-50. [PMID: 19741243 DOI: 10.1167/iovs.09-4117] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Choroideremia (CHM) is an X-linked progressive degeneration of the retinal pigment epithelium (RPE), photoreceptors, and choroid caused by mutations in the CHM gene, which encodes Rab escort-protein-1 (REP-1). REP-1 enables posttranslational isoprenyl modification of Rab GTPases, proteins that control vesicle formation, movement, docking, and fusion. The aim of this study was to determine the effect of REP-1 depletion on vesicular trafficking in phagocytic and secretory pathways of human RPE. METHODS In vitro, REP-1 expression was inhibited in human fetal RPE (hfRPE) cells by siRNA knockdown and its effects measured on the uptake of bovine photoreceptor outer segments (POS), proteolysis of POS rhodopsin, phagosomal pH, phagosome fusion with early and late endosomes/lysosomes, and polarized secretion of cytokines. RESULTS Depletion of REP-1 in human RPE cells did not affect POS internalization but reduced phagosomal acidification and delayed POS protein clearance. REP-1 depletion also caused a decrease in the association of POS-containing phagosomes with late endosomal markers (Rab7, LAMP-1) and increases in the secretion of monocyte chemotactic protein (MCP-1) and interleukin (IL)-8 by hfRPE cells. CONCLUSIONS Lack of REP-1 protein expression in hfRPE cells leads to reduced degradation of POS most likely because of the inhibition of phagosome-lysosome fusion events and increased constitutive secretion of MCP-1 and IL-8. These observations may explain the accumulation of unprocessed outer segments within the phagolysosomes of RPE cells and the presence of inflammatory cells in the choroid of patients with CHM.
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Affiliation(s)
- Nataliya V Gordiyenko
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, USA
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Lee MTG, Mishra A, Lambright DG. Structural mechanisms for regulation of membrane traffic by rab GTPases. Traffic 2009; 10:1377-89. [PMID: 19522756 DOI: 10.1111/j.1600-0854.2009.00942.x] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
In all eukaryotic organisms, Rab GTPases function as critical regulators of membrane traffic, organelle biogenesis and maturation, and related cellular processes. The numerous Rab proteins have distinctive yet overlapping subcellular distributions throughout the endomembrane system. Intensive investigation has clarified the underlying molecular and structural mechanisms for several ubiquitous Rab proteins that control membrane traffic between tubular-vesicular organelles in the exocytic, endocytic and recycling pathways. In this review, we focus on structural insights that inform our current understanding of the organization of the Rab family as well as the mechanisms for membrane targeting and activation, interaction with effectors, deactivation and specificity determination.
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Affiliation(s)
- Meng-Tse Gabe Lee
- Program in Molecular Medicine and Department of Biochemistry & Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA
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Simpson F, Kerr MC, Wicking C. Trafficking, development and hedgehog. Mech Dev 2009; 126:279-88. [PMID: 19368798 DOI: 10.1016/j.mod.2009.01.007] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2007] [Revised: 01/22/2009] [Accepted: 01/26/2009] [Indexed: 11/27/2022]
Abstract
Embryogenesis is mediated by a relatively small number of developmental signaling pathways, and the morphogens, receptors and transcription factors integral to these cascades are considered the master regulators of development. However, superimposed on this is an additional layer of control by complex intracellular trafficking networks. The importance of trafficking in controlling the processes of morphogenesis and development is highlighted by recent data regarding the transport and localisation of the morphogen sonic hedgehog (Shh) and the machinery that leads to its secretion, modification, cellular internalisation and signal transduction. Here we review the regulation of hedgehog signaling by intracellular trafficking, including the role of the primary cilium and lipids in mediating pathway activity.
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Affiliation(s)
- Fiona Simpson
- The University of Queensland, Institute for Molecular Bioscience, Qld, Australia
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Chapter 5: rab proteins and their interaction partners. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2009; 274:235-74. [PMID: 19349039 DOI: 10.1016/s1937-6448(08)02005-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The Ras superfamily consists of over 150 low molecular weight proteins that cycle between an inactive guanosine diphosphate (GDP)-bound state and an active guanosine triphosphate (GTP)-bound state. They are involved in a variety of signal transduction pathways that regulate cell growth, intracellular trafficking, cell migration, and apoptosis. Several methods have been devised to detect and characterize the interacting partners of small GTPases with the aim of better understanding their physiological function in normal cells and tumor cells. The Rab (Ras analog in brain) proteins form the largest family within the Ras superfamily. Rab proteins regulate vesicular trafficking pathways, behaving as membrane-associated molecular switches. The guanine nucleotide-binding status of Rab proteins is modulated by three different classes of regulatory proteins, which have been extensively studied for the Rab molecules but also for other subfamilies of the Ras superfamily. Furthermore, numerous effector molecules have been isolated especially for the Rab subfamily of proteins, which interact via a Rab-binding domain (RBD) and are recruited afterwards to specific sub-cellular compartments by the Rab proteins.
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48
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An Evolutionary Perspective on Eukaryotic Membrane Trafficking. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 607:73-83. [DOI: 10.1007/978-0-387-74021-8_6] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Frigieri MC, João Luiz MVS, Apponi LH, Zanelli CF, Valentini SR. Synthetic lethality between eIF5A and Ypt1 reveals a connection between translation and the secretory pathway in yeast. Mol Genet Genomics 2008; 280:211-21. [PMID: 18568365 DOI: 10.1007/s00438-008-0357-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2008] [Accepted: 06/03/2008] [Indexed: 12/27/2022]
Abstract
The putative translation initiation factor 5A (eIF5A) is a small protein, highly conserved and essential in all organisms from archaea to mammals. Although the involvement of eIF5A in translation initiation has been questioned, new evidence reestablished the connection between eIF5A and this cellular process. In order to better understand the function of elF5A, a screen for synthetic lethal gene using the tif51A-3 mutant was carried out and a new mutation (G80D) was found in the essential gene YPT1, encoding a protein involved in vesicular trafficking. The precursor form of the vacuolar protein CPY is accumulated in the ypt1-G80D mutant at the nonpermissive temperature, but this defect in vesicular trafficking did not occur in the tif51A mutants tested. Overexpression of eIF5A suppresses the growth defect of a series of ypt1 mutants, but this suppression does not restore correct CPY sorting. On the other hand, overexpression of YPT1 does not suppress the growth defect of tif51A mutants. Further, it was revealed that eIF-5A is present in both soluble and membrane fractions, and its membrane association is ribosome-dependent. Finally, we demonstrated that the ypt1 and other secretion pathway mutants are sensitive to paromomycin. These results confirm the link between translation and vesicular trafficking and reinforce the implication of eIF5A in protein synthesis.
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Affiliation(s)
- Mariana C Frigieri
- Department of Biological Sciences, School of Pharmaceutical Sciences, São Paulo State University, UNESP, Rod Araraquara-Jaú, km 1, Araraquara, SP, Brazil
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Review: Molecular mechanism of docking of dense-core vesicles to the plasma membrane in neuroendocrine cells. Med Mol Morphol 2008; 41:68-75. [DOI: 10.1007/s00795-008-0400-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2008] [Accepted: 03/04/2008] [Indexed: 02/06/2023]
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