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Gorgani S, Hosseini SA, Wang AZ, Baino F, Kargozar S. Effects of Bioactive Glasses (BGs) on Exosome Production and Secretion: A Critical Review. MATERIALS (BASEL, SWITZERLAND) 2023; 16:ma16114194. [PMID: 37297327 DOI: 10.3390/ma16114194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 05/30/2023] [Accepted: 06/01/2023] [Indexed: 06/12/2023]
Abstract
There is an increasing trend toward the application of bioactive glasses in different areas of biomedicine, including tissue engineering and oncology. The reason for this increase is mostly attributed to the inherent properties of BGs, such as excellent biocompatibility, and the ease of tailoring their properties by changing, for example, the chemical composition. Previous experiments have demonstrated that the interactions between BGs and their ionic dissolution products, and mammalian cells, can affect and change cellular behaviors, and thereby govern the performance of living tissues. However, limited research exists on their critical role in the production and secretion of extracellular vesicles (EVs) such as exosomes. Exosomes are nanosized membrane vesicles that carry various therapeutic cargoes such as DNA, RNA, proteins, and lipids, and thereby can govern cell-cell communication and subsequent tissue responses. The use of exosomes is currently considered a cell-free approach in tissue engineering strategies, due to their positive roles in accelerating wound healing. On the other hand, exosomes are known as key players in cancer biology (e.g., progression and metastasis), due to their capability to carry bioactive molecules between tumor cells and normal cells. Recent studies have demonstrated that the biological performance of BGs, including their proangiogenic activity, is accomplished with the help of exosomes. Indeed, therapeutic cargos (e.g., proteins) produced in BG-treated cells are transferred by a specific subset of exosomes toward target cells and tissues, and lead to a biological phenomenon. On the other hand, BGs are suitable delivery vehicles that can be utilized for the targeted delivery of exosomes to cells and tissues of interest. Therefore, it seems necessary to have a deeper understanding of the potential effects of BGs in the production of exosomes in cells that are involved in tissue repair and regeneration (mostly mesenchymal stem cells), as well as in those that play roles in cancer progression (e.g., cancer stem cells). This review aims to present an updated report on this critical issue, to provide a roadmap for future research in the fields of tissue engineering and regenerative medicine.
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Affiliation(s)
- Sara Gorgani
- Tissue Engineering Research Group (TERG), Department of Anatomy and Cell Biology, School of Medicine, Mashhad University of Medical Sciences, Mashhad 917794-8564, Iran
| | - Seyede Atefe Hosseini
- Department of Medical Biotechnology and Nanotechnology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad 917794-8564, Iran
| | - Andrew Z Wang
- Department of Radiation Oncology, Simmons Comprehensive Cancer Center, UT Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390, USA
| | - Francesco Baino
- Institute of Materials Physics and Engineering, Department of Applied Science and Technology, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino, Italy
| | - Saeid Kargozar
- Tissue Engineering Research Group (TERG), Department of Anatomy and Cell Biology, School of Medicine, Mashhad University of Medical Sciences, Mashhad 917794-8564, Iran
- Department of Radiation Oncology, Simmons Comprehensive Cancer Center, UT Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390, USA
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2
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The Rab GTPase in the heart: Pivotal roles in development and disease. Life Sci 2022; 306:120806. [PMID: 35841978 DOI: 10.1016/j.lfs.2022.120806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Revised: 07/03/2022] [Accepted: 07/11/2022] [Indexed: 11/20/2022]
Abstract
Rab proteins are a family of small GTPases that function as molecular switches of intracellular vesicle formation and membrane trafficking. As a key factor, Rab GTPase participates in autophagy and protein transport and acts as the central hub of membrane trafficking in eukaryotes. The role of Rab GTPase in neurodegenerative disorders, such as Alzheimer's and Parkinson's, has been extensively investigated; however, its implication in cardiovascular embryogenesis and diseases remains largely unknown. In this review, we summarize previous findings and reveal their importance in the onset and progression of cardiac diseases, as well as their emergence as potential therapeutic targets for cardiovascular disease.
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Prasai B, Haber GJ, Strub MP, Ahn R, Ciemniecki JA, Sochacki KA, Taraska JW. The nanoscale molecular morphology of docked exocytic dense-core vesicles in neuroendocrine cells. Nat Commun 2021; 12:3970. [PMID: 34172739 PMCID: PMC8233335 DOI: 10.1038/s41467-021-24167-9] [Citation(s) in RCA: 9] [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: 08/26/2020] [Accepted: 06/04/2021] [Indexed: 12/31/2022] Open
Abstract
Rab-GTPases and their interacting partners are key regulators of secretory vesicle trafficking, docking, and fusion to the plasma membrane in neurons and neuroendocrine cells. Where and how these proteins are positioned and organized with respect to the vesicle and plasma membrane are unknown. Here, we use correlative super-resolution light and platinum replica electron microscopy to map Rab-GTPases (Rab27a and Rab3a) and their effectors (Granuphilin-a, Rabphilin3a, and Rim2) at the nanoscale in 2D. Next, we apply a targetable genetically-encoded electron microscopy labeling method that uses histidine based affinity-tags and metal-binding gold-nanoparticles to determine the 3D axial location of these exocytic proteins and two SNARE proteins (Syntaxin1A and SNAP25) using electron tomography. Rab proteins are distributed across the entire surface and t-SNARE proteins at the base of docked vesicles. We propose that the circumferential distribution of Rabs and Rab-effectors could aid in the efficient transport, capture, docking, and rapid fusion of calcium-triggered exocytic vesicles in excitable cells.
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Affiliation(s)
- Bijeta Prasai
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Gideon J Haber
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Marie-Paule Strub
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Regina Ahn
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - John A Ciemniecki
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Kem A Sochacki
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Justin W Taraska
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
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4
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Wu Z, He D, Li H. Bioglass enhances the production of exosomes and improves their capability of promoting vascularization. Bioact Mater 2021; 6:823-835. [PMID: 33024902 PMCID: PMC7530219 DOI: 10.1016/j.bioactmat.2020.09.011] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 09/16/2020] [Accepted: 09/16/2020] [Indexed: 02/07/2023] Open
Abstract
Recently, exosomes have been extensively applied in tissue regeneration. However, their practical applications are severely restricted by the limited exosome secretion capability of cells. Therefore, developing strategies to enhance the production of exosomes and improve their biological function attracts great interest. Studies have shown that biomaterials can significantly enhance the paracrine effects of cells and exosomes are the main signal carriers of intercellular paracrine communication, thus biomaterials are considered to affect the exosome secretion of cells and their biological function. In this study, a widely recognized biomaterial, 45S5 Bioglass® (BG), is used to create a mild and cell-friendly microenvironment for mesenchymal stem cells (MSCs) with its ion products. Results showed that BG ion products can significantly improve exosome production of MSCs by upregulating the expression of neutral sphingomyelinase-2 (nSMase2) and Rab27a which enhanced the nSMases and Rab GTPases pathways, respectively. Besides, microRNA analysis indicates that BG ion products can modulate the cargoes of MSCs-derived exosomes by decreasing microRNA-342-5p level while increasing microRNA-1290 level. Subsequently, the function of exosomes is modified as their capabilities of promoting the vascularization of endothelial cells and facilitating the intradermal angiogenesis are enhanced. Taken together, BG ion products are confirmed to enhance exosome production and simultaneously improve exosome function, suggesting a feasible approach to improve the practical application of exosomes in regenerative medicine.
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Affiliation(s)
- Zhi Wu
- Shanghai Jiao Tong University Affiliated Sixth People's Hospital, School of Biomedical Engineering, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai, 200030, China
- Med-X Research Institute, School of Biomedical Engineering, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai, 200030, China
| | - Dan He
- Shanghai Jiao Tong University Affiliated Sixth People's Hospital, School of Biomedical Engineering, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai, 200030, China
- Med-X Research Institute, School of Biomedical Engineering, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai, 200030, China
| | - Haiyan Li
- Shanghai Jiao Tong University Affiliated Sixth People's Hospital, School of Biomedical Engineering, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai, 200030, China
- Med-X Research Institute, School of Biomedical Engineering, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai, 200030, China
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5
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Proteomics Study of Peripheral Blood Mononuclear Cells in Down Syndrome Children. Antioxidants (Basel) 2020; 9:antiox9111112. [PMID: 33187268 PMCID: PMC7696178 DOI: 10.3390/antiox9111112] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 10/22/2020] [Accepted: 11/09/2020] [Indexed: 02/07/2023] Open
Abstract
Down syndrome (DS) is the most common chromosomal disorder and the leading genetic cause of intellectual disability in humans, which results from the triplication of chromosome 21. To search for biomarkers for the early detection and exploration of the disease mechanisms, here, we investigated the protein expression signature of peripheral blood mononuclear cells (PBMCs) in DS children compared with healthy donors (HD) by using an in-depth label-free shotgun proteomics approach. Identified proteins are found associated with metabolic pathways, cellular trafficking, DNA structure, stress response, cytoskeleton network, and signaling pathways. The results showed that a well-defined number of dysregulated pathways retain a prominent role in mediating DS pathological features. Further, proteomics results are consistent with published study in DS and provide evidences that increased oxidative stress and the increased induction of stress related response, is a participant in DS pathology. In addition, the expression levels of some key proteins have been validated by Western blot analysis while protein carbonylation, as marker of protein oxidation, was investigated. The results of this study propose that PBMCs from DS children might be in an activated state where endoplasmic reticulum stress and increased production of radical species are one of the primary events contributing to multiple DS pathological features.
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New Perspectives on SNARE Function in the Yeast Minimal Endomembrane System. Genes (Basel) 2020; 11:genes11080899. [PMID: 32781543 PMCID: PMC7465790 DOI: 10.3390/genes11080899] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/31/2020] [Accepted: 08/02/2020] [Indexed: 02/06/2023] Open
Abstract
Saccharomyces cerevisiae is one of the best model organisms for the study of endocytic membrane trafficking. While studies in mammalian cells have characterized the temporal and morphological features of the endocytic pathway, studies in budding yeast have led the way in the analysis of the endosomal trafficking machinery components and their functions. Eukaryotic endomembrane systems were thought to be highly conserved from yeast to mammals, with the fusion of plasma membrane-derived vesicles to the early or recycling endosome being a common feature. Upon endosome maturation, cargos are then sorted for reuse or degraded via the endo-lysosomal (endo-vacuolar in yeast) pathway. However, recent studies have shown that budding yeast has a minimal endomembrane system that is fundamentally different from that of mammalian cells, with plasma membrane-derived vesicles fusing directly to a trans-Golgi compartment which acts as an early endosome. Thus, the Golgi, rather than the endosome, acts as the primary acceptor of endocytic vesicles, sorting cargo to pre-vacuolar endosomes for degradation. The field must now integrate these new findings into a broader understanding of the endomembrane system across eukaryotes. This article synthesizes what we know about the machinery mediating endocytic membrane fusion with this new model for yeast endomembrane function.
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Lawson T, Lycett GW, Mayes S, Ho WK, Chin CF. Transcriptome-wide identification and characterization of the Rab GTPase family in mango. Mol Biol Rep 2020; 47:4183-4197. [PMID: 32444976 DOI: 10.1007/s11033-020-05519-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 05/14/2020] [Indexed: 10/24/2022]
Abstract
The Rab GTPase family plays a vital role in several plant physiological processes including fruit ripening. Fruit softening during ripening involves trafficking of cell wall polymers and enzymes between cellular compartments. Mango, an economically important fruit crop, is known for its delicious taste, exotic flavour and nutritional value. So far, there is a paucity of information on the mango Rab GTPase family. In this study, 23 genes encoding Rab proteins were identified in mango by a comprehensive in silico approach. Sequence alignment and similarity tree analysis with the model plant Arabidopsis as a reference enabled the bona fide assignment of the deduced mango proteins to classify into eight subfamilies. Expression analysis by RNA-Sequencing (RNA-Seq) showed that the Rab genes were differentially expressed in ripe and unripe mangoes suggesting the involvement of vesicle trafficking during ripening. Interaction analysis showed that the proteins involved in vesicle trafficking and cell wall softening were interconnected providing further evidence of the involvement of the Rab GTPases in fruit softening. Correlation analyses showed a significant relationship between the expression level of the RabA3 and RabA4 genes and fruit firmness at the unripe stage of the mango varieties suggesting that the differences in gene expression level might be associated with the contrasting firmness of these varieties. This study will not only provide new insights into the complexity of the ripening-regulated molecular mechanism but also facilitate the identification of potential Rab GTPases to address excessive fruit softening.
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Affiliation(s)
- Tamunonengiyeofori Lawson
- School of Biosciences, Faculty of Science, The University of Nottingham, Jalan Broga, 43500, Semenyih, Selangor Darul Ehsan, Malaysia.,Division of Plant and Crop Sciences, School of Biosciences, The University of Nottingham, Sutton Bonington Campus, Loughborough, LE12 5RD, UK.,Crops for the Future (CFF) Jalan Broga, 43500, Semenyih, Selangor Darul Ehsan, Malaysia
| | - Grantley W Lycett
- Division of Plant and Crop Sciences, School of Biosciences, The University of Nottingham, Sutton Bonington Campus, Loughborough, LE12 5RD, UK
| | - Sean Mayes
- Division of Plant and Crop Sciences, School of Biosciences, The University of Nottingham, Sutton Bonington Campus, Loughborough, LE12 5RD, UK.,Crops for the Future (CFF) Jalan Broga, 43500, Semenyih, Selangor Darul Ehsan, Malaysia
| | - Wai Kuan Ho
- School of Biosciences, Faculty of Science, The University of Nottingham, Jalan Broga, 43500, Semenyih, Selangor Darul Ehsan, Malaysia.,Crops for the Future (CFF) Jalan Broga, 43500, Semenyih, Selangor Darul Ehsan, Malaysia
| | - Chiew Foan Chin
- School of Biosciences, Faculty of Science, The University of Nottingham, Jalan Broga, 43500, Semenyih, Selangor Darul Ehsan, Malaysia.
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8
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Ebanks K, Lewis PA, Bandopadhyay R. Vesicular Dysfunction and the Pathogenesis of Parkinson's Disease: Clues From Genetic Studies. Front Neurosci 2020; 13:1381. [PMID: 31969802 PMCID: PMC6960401 DOI: 10.3389/fnins.2019.01381] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 12/05/2019] [Indexed: 12/14/2022] Open
Abstract
Parkinson's disease (PD) is a common age-related neurodegenerative disorder with disabling motor symptoms and no available disease modifying treatment. The majority of the PD cases are of unknown etiology, with both genetics and environment playing important roles. Over the past 25 years, however, genetic analysis of patients with familial history of Parkinson's and, latterly, genome wide association studies (GWAS) have provided significant advances in our understanding of the causes of the disease. These genetic insights have uncovered pathways that are affected in both genetic and sporadic forms of PD. These pathways involve oxidative stress, abnormal protein homeostasis, mitochondrial dysfunction, and lysosomal defects. In addition, newly identified PD genes and GWAS nominated genes point toward synaptic changes involving vesicles. This review will highlight the genes that contribute PD risk relating to intracellular vesicle trafficking and their functional consequences. There is still much to investigate on this newly identified and converging pathway of vesicular dynamics and PD, which will aid in better understanding and suggest novel therapeutic strategies for PD patients.
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Affiliation(s)
- Kirsten Ebanks
- Reta Lila Weston Institute, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
- Department of Clinical and Motor Neuroscience, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Patrick A. Lewis
- School of Pharmacy, University of Reading, Reading, United Kingdom
- Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Rina Bandopadhyay
- Reta Lila Weston Institute, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
- Department of Clinical and Motor Neuroscience, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
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9
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Zhang H, Gao Y, Qian P, Dong Z, Hao W, Liu D, Duan X. Expression analysis of Rab11 during zebrafish embryonic development. BMC DEVELOPMENTAL BIOLOGY 2019; 19:25. [PMID: 31884948 PMCID: PMC6936149 DOI: 10.1186/s12861-019-0207-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Accepted: 12/11/2019] [Indexed: 12/15/2022]
Abstract
Background Rab proteins are GTPases responsible for intracellular vesicular trafficking regulation. Rab11 proteins, members of the Rab GTPase family, are known to regulate vesicular recycling during embryonic development. In zebrafish, there are 3 rab11 paralogues, known as rab11a, rab11ba and rab11bb, sharing high identity with each other. However, the expression analysis of rab11 is so far lacking. Results Here, by phylogeny analysis, we found the three rab11 genes are highly conserved especially for their GTPase domains. We examined the expression patterns of rab11a, rab11ba and rab11bb using RT-PCR and in situ hybridization. We found that all the three genes were highly enriched in the central nervous system, but in different areas of the brain. Apart from brain, rab11a was also expressed in caudal vein, pronephric duct, proctodeum, pharyngeal arches and digestive duct, rab11ba was detected to express in muscle, and rab11bb was expressed in kidney, fin and spinal cord. Different from rab11a and rab11ba, which both have maternal expressions in embryos, rab11bb only expresses during 24hpf to 96hpf. Conclusions Our results suggest that rab11 genes play important but distinct roles in the development of the nervous system in zebrafish. The findings could provide new evidences for better understanding the functions of rab11 in the development of zebrafish embryos.
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Affiliation(s)
- Haijun Zhang
- Co-innovation Center of Neuroregeneration, Jiangsu Key Laboratory of Neuroregeneration, Nantong University, 19# Qixiu Road, Nantong, 226001, China
| | - Yu Gao
- Co-innovation Center of Neuroregeneration, Jiangsu Key Laboratory of Neuroregeneration, Nantong University, 19# Qixiu Road, Nantong, 226001, China
| | - Peipei Qian
- Co-innovation Center of Neuroregeneration, Jiangsu Key Laboratory of Neuroregeneration, Nantong University, 19# Qixiu Road, Nantong, 226001, China
| | - Zhangji Dong
- Co-innovation Center of Neuroregeneration, Jiangsu Key Laboratory of Neuroregeneration, Nantong University, 19# Qixiu Road, Nantong, 226001, China
| | - Wenjin Hao
- College of life science, Nantong University, 9# Seyuan Road, Nantong, 226001, China
| | - Dong Liu
- College of life science, Nantong University, 9# Seyuan Road, Nantong, 226001, China
| | - Xuchu Duan
- College of life science, Nantong University, 9# Seyuan Road, Nantong, 226001, China.
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10
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Li T, Yue J, Huang L, Yang M. Autophagy inhibitor Vacuolin-1 interferes with lipid-based small interference RNA delivery. Biochem Biophys Res Commun 2019; 510:427-434. [PMID: 30732855 DOI: 10.1016/j.bbrc.2019.01.121] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 01/27/2019] [Indexed: 01/12/2023]
Abstract
Autophagy and endocytosis are important pathways regulating macromolecule recycling and regeneration. Small molecule inhibitors are utilized to modulate these pathways and to treat autophagy-related diseases. Vacuolin-1 is a small molecule that can potently and reversibly inhibit autophagy by activating Rab5. In addition, Vacuolin-1 can be applied to inhibit exocytosis in a variety of cell types. Here we report that Vacuolin-1 significantly reduces small interference RNA (siRNA)-mediated gene silencing delivered by liposome transfection reagent or lipid nanoparticles in Hela cells. Vacuolin-1 exhibits the strongest inhibition effect among a few autophagy inhibitors including Chloroquine, Wortmannin, and Bafilomycin A1. We found that siRNAs are over-accumulated intracellularly and colocalized with a late endosome marker Rab7 in Vacuolin-1 treated cells, suggesting Vacuolin-1 inhibits the cytoplasmic release of lipid siRNA complexes from late endosomes. We propose that Vacuolin-1 could potentially be used to control the effects of lipid nanoparticle-based RNAi and gene therapy drugs.
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Affiliation(s)
- Tianzhong Li
- Department of Biomedical Sciences, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong SAR, China
| | - Jianbo Yue
- Department of Biomedical Sciences, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong SAR, China
| | - Linfeng Huang
- Department of Biomedical Sciences, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong SAR, China; Biotechnology and Health Centre, City University of Hong Kong Shenzhen Research Institute, 8 Yuexing 1st Road, Shenzhen Hi-Tech Industrial Park, Nanshan District, Shenzhen, China.
| | - Mengsu Yang
- Department of Biomedical Sciences, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong SAR, China; Biotechnology and Health Centre, City University of Hong Kong Shenzhen Research Institute, 8 Yuexing 1st Road, Shenzhen Hi-Tech Industrial Park, Nanshan District, Shenzhen, China.
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11
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Dingjan I, Linders PTA, Verboogen DRJ, Revelo NH, Ter Beest M, van den Bogaart G. Endosomal and Phagosomal SNAREs. Physiol Rev 2018; 98:1465-1492. [PMID: 29790818 DOI: 10.1152/physrev.00037.2017] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) protein family is of vital importance for organelle communication. The complexing of cognate SNARE members present in both the donor and target organellar membranes drives the membrane fusion required for intracellular transport. In the endocytic route, SNARE proteins mediate trafficking between endosomes and phagosomes with other endosomes, lysosomes, the Golgi apparatus, the plasma membrane, and the endoplasmic reticulum. The goal of this review is to provide an overview of the SNAREs involved in endosomal and phagosomal trafficking. Of the 38 SNAREs present in humans, 30 have been identified at endosomes and/or phagosomes. Many of these SNAREs are targeted by viruses and intracellular pathogens, which thereby reroute intracellular transport for gaining access to nutrients, preventing their degradation, and avoiding their detection by the immune system. A fascinating picture is emerging of a complex transport network with multiple SNAREs being involved in consecutive trafficking routes.
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Affiliation(s)
- Ilse Dingjan
- Department of Tumor Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center , Nijmegen , The Netherlands ; and Department of Molecular Immunology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen , Groningen , The Netherlands
| | - Peter T A Linders
- Department of Tumor Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center , Nijmegen , The Netherlands ; and Department of Molecular Immunology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen , Groningen , The Netherlands
| | - Danielle R J Verboogen
- Department of Tumor Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center , Nijmegen , The Netherlands ; and Department of Molecular Immunology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen , Groningen , The Netherlands
| | - Natalia H Revelo
- Department of Tumor Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center , Nijmegen , The Netherlands ; and Department of Molecular Immunology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen , Groningen , The Netherlands
| | - Martin Ter Beest
- Department of Tumor Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center , Nijmegen , The Netherlands ; and Department of Molecular Immunology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen , Groningen , The Netherlands
| | - Geert van den Bogaart
- Department of Tumor Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center , Nijmegen , The Netherlands ; and Department of Molecular Immunology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen , Groningen , The Netherlands
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12
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Song S, Cong W, Zhou S, Shi Y, Dai W, Zhang H, Wang X, He B, Zhang Q. Small GTPases: Structure, biological function and its interaction with nanoparticles. Asian J Pharm Sci 2018; 14:30-39. [PMID: 32104436 PMCID: PMC7032109 DOI: 10.1016/j.ajps.2018.06.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 06/06/2018] [Accepted: 06/13/2018] [Indexed: 12/12/2022] Open
Abstract
Small GTPase is a kind of GTP-binding protein commonly found in eukaryotic cells. It plays an important role in cytoskeletal reorganization, cell polarity, cell cycle progression, gene expression and many other significant events in cells, such as the interaction with foreign particles. Therefore, it is of great scientific significance to understand the biological properties of small GTPases as well as the GTPase-nano interplay, since more and more nanomedicine are supposed to be used in biomedical field. However, there is no review in this aspect. This review summarizes the small GTPases in terms of the structure, biological function and its interaction with nanoparticles. We briefly introduced the various nanoparticles such as gold/silver nanoparticles, SWCNT, polymeric micelles and other nano delivery systems that interacted with different GTPases. These current nanoparticles exhibited different pharmacological effect modes and various target design concepts in the small GTPases study. This will help to elucidate the conclusion that the therapeutic strategy targeting small GTPases might be a new research direction. It is believed that the in-depth study on the functional mechanism of GTPases can provide insights for the design and study of nanomedicines.
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Affiliation(s)
- Siyang Song
- Shenyang Pharmaceutical University, No. 103, Wenhua Road, Shenyang 110016, China.,Peking University, No. 38, Xueyuan Road, Beijing 100191, China
| | - Wenshu Cong
- Peking University, No. 38, Xueyuan Road, Beijing 100191, China
| | - Shurong Zhou
- Peking University, No. 38, Xueyuan Road, Beijing 100191, China
| | - Yujie Shi
- Peking University, No. 38, Xueyuan Road, Beijing 100191, China
| | - Wenbing Dai
- Peking University, No. 38, Xueyuan Road, Beijing 100191, China
| | - Hua Zhang
- Peking University, No. 38, Xueyuan Road, Beijing 100191, China
| | - Xueqing Wang
- Peking University, No. 38, Xueyuan Road, Beijing 100191, China
| | - Bing He
- Peking University, No. 38, Xueyuan Road, Beijing 100191, China
| | - Qiang Zhang
- Shenyang Pharmaceutical University, No. 103, Wenhua Road, Shenyang 110016, China.,Peking University, No. 38, Xueyuan Road, Beijing 100191, China
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13
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Vagne Q, Sens P. Stochastic Model of Maturation and Vesicular Exchange in Cellular Organelles. Biophys J 2018; 114:947-957. [PMID: 29490254 PMCID: PMC5984994 DOI: 10.1016/j.bpj.2017.12.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 12/14/2017] [Accepted: 12/18/2017] [Indexed: 11/21/2022] Open
Abstract
The dynamical organization of membrane-bound organelles along intracellular transport pathways relies on vesicular exchange between organelles and on the maturation of the organelle's composition by enzymatic reactions or exchange with the cytoplasm. The relative importance of each mechanism in controlling organelle dynamics remains controversial, in particular for transport through the Golgi apparatus. Using a stochastic model, we identify two classes of dynamical behavior that can lead to full maturation of membrane-bound compartments. In the first class, maturation corresponds to the stochastic escape from a steady state in which export is dominated by vesicular exchange, and is very unlikely for large compartments. In the second class, it occurs in a quasi-deterministic fashion and is almost size independent. Whether a system belongs to the first or second class is largely controlled by homotypic fusion.
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Affiliation(s)
- Quentin Vagne
- Institut Curie, PSL Research University, CNRS, UMR 168, Paris, France
| | - Pierre Sens
- Institut Curie, PSL Research University, CNRS, UMR 168, Paris, France.
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14
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Jonker CTH, Galmes R, Veenendaal T, Ten Brink C, van der Welle REN, Liv N, de Rooij J, Peden AA, van der Sluijs P, Margadant C, Klumperman J. Vps3 and Vps8 control integrin trafficking from early to recycling endosomes and regulate integrin-dependent functions. Nat Commun 2018; 9:792. [PMID: 29476049 PMCID: PMC5824891 DOI: 10.1038/s41467-018-03226-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 01/30/2018] [Indexed: 01/09/2023] Open
Abstract
Recycling endosomes maintain plasma membrane homeostasis and are important for cell polarity, migration, and cytokinesis. Yet, the molecular machineries that drive endocytic recycling remain largely unclear. The CORVET complex is a multi-subunit tether required for fusion between early endosomes. Here we show that the CORVET-specific subunits Vps3 and Vps8 also regulate vesicular transport from early to recycling endosomes. Vps3 and Vps8 localise to Rab4-positive recycling vesicles and co-localise with the CHEVI complex on Rab11-positive recycling endosomes. Depletion of Vps3 or Vps8 does not affect transferrin recycling, but delays the delivery of internalised integrins to recycling endosomes and their subsequent return to the plasma membrane. Consequently, Vps3/8 depletion results in defects in integrin-dependent cell adhesion and spreading, focal adhesion formation, and cell migration. These data reveal a role for Vps3 and Vps8 in a specialised recycling pathway important for integrin trafficking.
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Affiliation(s)
- C T H Jonker
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.,Department of Ophthalmology, Weill Cornell Medicine, 1300 York Ave, New York, NY, 10065, USA
| | - R Galmes
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.,UCL Cancer Institute, University College London, 72 Huntley Street, London, WC1E 6DD, UK
| | - T Veenendaal
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
| | - C Ten Brink
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
| | - R E N van der Welle
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
| | - N Liv
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
| | - J de Rooij
- Section Molecular Cancer Research, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht Universty, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
| | - A A Peden
- Department of Biomedical Science, The University of Sheffield, Sheffield, S10 2TN, UK
| | - P van der Sluijs
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.,Cellular Protein Chemistry, Bijvoet Center for Biomolecular Research, Utrecht University, 3584, CH Utrecht, The Netherlands
| | - C Margadant
- Department of Molecular Cell Biology, Sanquin Research, Plesmanlaan 125, 1066 CX, Amsterdam, The Netherlands
| | - J Klumperman
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.
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15
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Li Y, Wang S, Li T, Zhu L, Xu Y, Ma C. A Stimulation Function of Synaptotagmin-1 in Ternary SNARE Complex Formation Dependent on Munc18 and Munc13. Front Mol Neurosci 2017; 10:256. [PMID: 28860966 PMCID: PMC5559510 DOI: 10.3389/fnmol.2017.00256] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2017] [Accepted: 07/28/2017] [Indexed: 12/12/2022] Open
Abstract
The Ca2+ sensor synaptotagmin-1 (Syt1) plays an essential function in synaptic exocytosis. Recently, Syt1 has been implicated in synaptic vesicle priming, a maturation step prior to Ca2+-triggered membrane fusion that is believed to involve formation of the ternary SNARE complex and require priming proteins Munc18-1 and Munc13-1. However, the mechanisms of Syt1 in synaptic vesicle priming are still unclear. In this study, we found that Syt1 stimulates the transition from the Munc18-1/syntaxin-1 complex to the ternary SNARE complex catalyzed by Munc13-1. This stimulation can be further enhanced in a membrane-containing environment. Further, we showed that Syt1, together with Munc18-1 and Munc13-1, stimulates trans ternary SNARE complex formation on membranes in a manner resistant to disassembly factors NSF and α-SNAP. Disruption of a proposed Syt1/SNARE binding interface strongly abrogated the stimulation function of Syt1. Our results suggest that binding of Syt1 to an intermediate SNARE assembly with Munc18-1 and Munc13-1 is critical for the stimulation function of Syt1 in ternary SNARE complex formation, and this stimulation may underlie the priming function of Syt1 in synaptic exocytosis.
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Affiliation(s)
- Yun Li
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and TechnologyWuhan, China
| | - Shen Wang
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and TechnologyWuhan, China
| | - Tianzhi Li
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and TechnologyWuhan, China
| | - Le Zhu
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and TechnologyWuhan, China
| | - Yuanyuan Xu
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and TechnologyWuhan, China
| | - Cong Ma
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and TechnologyWuhan, China
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16
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Ramadass M, Catz SD. Molecular mechanisms regulating secretory organelles and endosomes in neutrophils and their implications for inflammation. Immunol Rev 2017; 273:249-65. [PMID: 27558339 DOI: 10.1111/imr.12452] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Neutrophils constitute the first line of cellular defense against invading microorganisms and modulate the subsequent innate and adaptive immune responses. In order to execute a rapid and precise response to infections, neutrophils rely on preformed effector molecules stored in a variety of intracellular granules. Neutrophil granules contain microbicidal factors, the membrane-bound components of the respiratory burst oxidase, membrane-bound adhesion molecules, and receptors that facilitate the execution of all neutrophil functions including adhesion, transmigration, phagocytosis, degranulation, and neutrophil extracellular trap formation. The rapid mobilization of intracellular organelles is regulated by vesicular trafficking mechanisms controlled by effector molecules that include small GTPases and their interacting proteins. In this review, we focus on recent discoveries of mechanistic processes that are at center stage of the regulation of neutrophil function, highlighting the discrete and selective pathways controlled by trafficking modulators. In particular, we describe novel pathways controlled by the Rab27a effectors JFC1 and Munc13-4 in the regulation of degranulation, reactive oxygen species and neutrophil extracellular trap production, and endolysosomal signaling. Finally, we discuss the importance of understanding these molecular mechanisms in order to design novel approaches to modulate neutrophil-mediated inflammatory processes in a targeted fashion.
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Affiliation(s)
- Mahalakshmi Ramadass
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | - Sergio D Catz
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA, USA
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17
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Wild F, Khan MM, Straka T, Rudolf R. Progress of endocytic CHRN to autophagic degradation is regulated by RAB5-GTPase and T145 phosphorylation of SH3GLB1 at mouse neuromuscular junctions in vivo. Autophagy 2016; 12:2300-2310. [PMID: 27715385 DOI: 10.1080/15548627.2016.1234564] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Endocytosed nicotinic acetylcholine receptors (CHRN) are degraded via macroautophagy/autophagy during atrophic conditions and are accompanied by the autophagic regulator protein SH3GLB1. The present study addressed the functional role of SH3GLB1 on CHRN trafficking and its implementation. We found an augmented ratio of total SH3GLB1 to threonine-145 phosphorylated SH3GLB1 (SH3GLB1:p-SH3GLB1) under conditions of increased CHRN vesicle numbers. Overexpression of T145 phosphomimetic (T145E) and phosphodeficient (T145A) mutants of SH3GLB1, was found to either slow down or augment the processing of endocytic CHRN vesicles, respectively. Co-expression of the early endosomal orchestrator RAB5 largely rescued the slow processing of endocytic CHRN vesicles induced by T145E. SH3GLB1 phosphomutants did not modulate the expression or colocalization of RAB5 with CHRN vesicles, but instead altered the expression of RAB5 activity regulators. In summary, these findings suggest that SH3GLB1 controls CHRN endocytic trafficking in a phosphorylation- and RAB5-dependent manner at steps upstream of autophagosome formation.
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Affiliation(s)
- Franziska Wild
- a Interdisciplinary Center for Neurosciences, University of Heidelberg , Heidelberg , Germany.,b Institute of Molecular and Cell Biology, Mannheim University of Applied Sciences , Mannheim , Germany.,c Institute of Toxicology and Genetics, Karlsruhe Institute of Technology , Eggenstein-Leopoldshafen , Germany
| | - Muzamil Majid Khan
- a Interdisciplinary Center for Neurosciences, University of Heidelberg , Heidelberg , Germany.,b Institute of Molecular and Cell Biology, Mannheim University of Applied Sciences , Mannheim , Germany.,c Institute of Toxicology and Genetics, Karlsruhe Institute of Technology , Eggenstein-Leopoldshafen , Germany
| | - Tatjana Straka
- a Interdisciplinary Center for Neurosciences, University of Heidelberg , Heidelberg , Germany.,b Institute of Molecular and Cell Biology, Mannheim University of Applied Sciences , Mannheim , Germany
| | - Rüdiger Rudolf
- a Interdisciplinary Center for Neurosciences, University of Heidelberg , Heidelberg , Germany.,b Institute of Molecular and Cell Biology, Mannheim University of Applied Sciences , Mannheim , Germany.,c Institute of Toxicology and Genetics, Karlsruhe Institute of Technology , Eggenstein-Leopoldshafen , Germany
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18
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Goulidaki N, Alarifi S, Alkahtani SH, Al-Qahtani A, Spandidos DA, Stournaras C, Sourvinos G. RhoB is a component of the human cytomegalovirus assembly complex and is required for efficient viral production. Cell Cycle 2016; 14:2748-63. [PMID: 26114383 DOI: 10.1080/15384101.2015.1066535] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Human Cytomegalovirus (HCMV), an ubiquitous β-herpesvirus, is a significant pathogen that causes medically severe diseases in immunocompromised individuals and in congenitally infected neonates. RhoB belongs to the family of Rho GTPases, which regulates diverse cellular processes. Rho proteins are implicated in the entry and egress from the host cell of mainly α- and γ-herpesviruses, whereas β-herpesviruses are the least studied in this regard. Here, we studied the role of RhoB GTPase during HCMV lytic infection. Microscopy analysis, both in fixed and live infected cells showed that RhoB was translocated to the assembly complex/compartment (AC) of HCMV, a cytoplasmic zone in infected cells where many viral structural proteins are known to accumulate and assembly of new virions takes place. Furthermore, RhoB was localized at the AC even when the expression of the late HCMV AC proteins was inhibited. At the very late stages of infection, cellular projections were formed containing RhoB and HCMV virions, potentially contributing to the successful viral spread. Interestingly, the knockdown of RhoB in HCMV-infected cells resulted in a significant reduction of the virus titer and could also affect the accumulation of AC viral proteins at this subcellular compartment. RhoB knockdown also affected actin fibers' structure. Actin reorganization was observed at late stages of infection originating from the viral AC and surrounding the cellular projections, implying a potential interplay between RhoB and actin during HCMV assembly and egress. In conclusion, our results demonstrate for the first time that RhoB is a constituent of the viral AC and is required for HCMV productive infection.
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Affiliation(s)
- Nektaria Goulidaki
- a Laboratory of Virology ; Medical School ; University of Crete ; Heraklion, Crete , Greece
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19
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Schöppner P, Csaba G, Braun T, Daake M, Richter B, Lange OF, Zacharias M, Zimmer R, Haslbeck M. Regulatory Implications of Non-Trivial Splicing: Isoform 3 of Rab1A Shows Enhanced Basal Activity and Is Not Controlled by Accessory Proteins. J Mol Biol 2016; 428:1544-57. [PMID: 26953259 DOI: 10.1016/j.jmb.2016.02.028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2015] [Revised: 02/19/2016] [Accepted: 02/24/2016] [Indexed: 01/04/2023]
Abstract
Alternative splicing often affects structured and highly conserved regions of proteins, generating so called non-trivial splicing variants of unknown structure and cellular function. The human small G-protein Rab1A is involved in the regulation of the vesicle transfer from the ER to Golgi. A conserved non-trivial splice variant lacks nearly 40% of the sequence of the native Rab1A, including most of the regulatory interaction sites. We show that this variant of Rab1A represents a stable and folded protein, which is still able to bind nucleotides and co-localizes with membranes. Nevertheless, it should be mentioned that compared to other wild-typeRabGTPases, the measured nucleotide binding affinities are dramatically reduced in the variant studied. Furthermore, the Rab1A variant forms hetero-dimers with wild-type Rab1A and its presence in the cell enhances the efficiency of alkaline phosphatase secretion. However, this variant shows no specificity for GXP nucleotides, a constantly enhanced GTP hydrolysis activity and is no longer controlled by GEF or GAP proteins, indicating a new regulatory mechanism for the Rab1A cycle via alternative non-trivial splicing.
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Affiliation(s)
- Patricia Schöppner
- Center for Integrated Protein Science, Department Chemie, Technische Universität München, Lichtenbergstrasse 4, 85748 Garching, Germany
| | - Gergely Csaba
- Department of Informatics, Ludwig-Maximilians-Universität München, Amalienstr. 17, 80333 München, Germany
| | - Tatjana Braun
- Center for Integrated Protein Science, Department Chemie, Technische Universität München, Lichtenbergstrasse 4, 85748 Garching, Germany
| | - Marina Daake
- Center for Integrated Protein Science, Department Chemie, Technische Universität München, Lichtenbergstrasse 4, 85748 Garching, Germany
| | - Bettina Richter
- Center for Integrated Protein Science, Department Chemie, Technische Universität München, Lichtenbergstrasse 4, 85748 Garching, Germany
| | - Oliver F Lange
- Center for Integrated Protein Science, Department Chemie, Technische Universität München, Lichtenbergstrasse 4, 85748 Garching, Germany
| | - Martin Zacharias
- Physics Department, Technische Universität München, James-Franck-Strasse 1, 85747 Garching, Germany
| | - Ralf Zimmer
- Department of Informatics, Ludwig-Maximilians-Universität München, Amalienstr. 17, 80333 München, Germany.
| | - Martin Haslbeck
- Center for Integrated Protein Science, Department Chemie, Technische Universität München, Lichtenbergstrasse 4, 85748 Garching, Germany.
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20
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Choi JY, Shin YC, Yoon JH, Kim CM, Lee JH, Jeon JH, Park HH. Molecular mechanism of constitutively active Rab11A was revealed by crystal structure of Rab11A S20V. FEBS Lett 2016; 590:819-27. [PMID: 26879265 DOI: 10.1002/1873-3468.12100] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 02/02/2016] [Accepted: 02/05/2016] [Indexed: 11/06/2022]
Abstract
Rab11A is a small GTP-binding protein involved in the regulation of vesicle trafficking during recycling of endosomes. Substitution of S20 to V (S20V) at Rab11A inhibits the GTP hydrolysis activity of Rab11A. This mutation is known to be constitutively in an active form. Here, we report the crystal structure of the human Rab11A S20V mutant form complexed with GTP at a resolution of 2.4 Å. Without adding any substrate, Rab11A contained non-hydrolyzed natural substrate GTP in the nucleotide binding pocket with Mg(2+). In our observations, substituted V20 of Rab11A was found to interfere with proper localization of the water molecule, which mediated GTP hydrolysis, resulting in GTP being locked in an active form of Rab11A S20V.
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Affiliation(s)
- Jae Young Choi
- School of Biotechnology and Graduate School of Biochemistry at Yeungnam University, Gyeongsan, South Korea
| | - Young-Cheul Shin
- Department of Physiology, Department of Biomedical Sciences, and Institute of Dermatological Science, Seoul National University College of Medicine, South Korea
| | - Jong Hwan Yoon
- School of Biotechnology and Graduate School of Biochemistry at Yeungnam University, Gyeongsan, South Korea
| | - Chang Min Kim
- School of Biotechnology and Graduate School of Biochemistry at Yeungnam University, Gyeongsan, South Korea
| | - Jun Hyuck Lee
- Division of Polar Life Sciences, Korea Polar Research Institute, Inchon, South Korea
| | - Ju-Hong Jeon
- Department of Physiology, Department of Biomedical Sciences, and Institute of Dermatological Science, Seoul National University College of Medicine, South Korea
| | - Hyun Ho Park
- School of Biotechnology and Graduate School of Biochemistry at Yeungnam University, Gyeongsan, South Korea
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21
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Schmidt JR, Kliemt S, Preissler C, Moeller S, von Bergen M, Hempel U, Kalkhof S. Osteoblast-released Matrix Vesicles, Regulation of Activity and Composition by Sulfated and Non-sulfated Glycosaminoglycans. Mol Cell Proteomics 2015; 15:558-72. [PMID: 26598647 DOI: 10.1074/mcp.m115.049718] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Indexed: 01/01/2023] Open
Abstract
Our aging population has to deal with the increasing threat of age-related diseases that impair bone healing. One promising therapeutic approach involves the coating of implants with modified glycosaminoglycans (GAGs) that mimic the native bone environment and actively facilitate skeletogenesis. In previous studies, we reported that coatings containing GAGs, such as hyaluronic acid (HA) and its synthetically sulfated derivative (sHA1) as well as the naturally low-sulfated GAG chondroitin sulfate (CS1), reduce the activity of bone-resorbing osteoclasts, but they also induce functions of the bone-forming cells, the osteoblasts. However, it remained open whether GAGs influence the osteoblasts alone or whether they also directly affect the formation, composition, activity, and distribution of osteoblast-released matrix vesicles (MV), which are supposed to be the active machinery for bone formation. Here, we studied the molecular effects of sHA1, HA, and CS1 on MV activity and on the distribution of marker proteins. Furthermore, we used comparative proteomic methods to study the relative protein compositions of isolated MVs and MV-releasing osteoblasts. The MV proteome is much more strongly regulated by GAGs than the cellular proteome. GAGs, especially sHA1, were found to severely impact vesicle-extracellular matrix interaction and matrix vesicle activity, leading to stronger extracellular matrix formation and mineralization. This study shows that the regulation of MV activity is one important mode of action of GAGs and provides information on underlying molecular mechanisms.
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Affiliation(s)
- Johannes R Schmidt
- From the ‡Department of Proteomics, Helmholtz Centre for Environmental Research UFZ, 04318 Leipzig, Germany
| | - Stefanie Kliemt
- From the ‡Department of Proteomics, Helmholtz Centre for Environmental Research UFZ, 04318 Leipzig, Germany
| | - Carolin Preissler
- the ‖Institute of Physiological Chemistry, TU Dresden, 01307 Dresden, Germany
| | | | - Martin von Bergen
- From the ‡Department of Proteomics, Helmholtz Centre for Environmental Research UFZ, 04318 Leipzig, Germany; the ‡‡Department of Metabolomics, Helmholtz Centre for Environmental Research UFZ, 04318 Leipzig, Germany; §§Department of Chemistry and Bioscience, Aalborg University, 9220 Aalborg East, Denmark
| | - Ute Hempel
- the ‖Institute of Physiological Chemistry, TU Dresden, 01307 Dresden, Germany;
| | - Stefan Kalkhof
- From the ‡Department of Proteomics, Helmholtz Centre for Environmental Research UFZ, 04318 Leipzig, Germany; the ¶¶Department of Bioanalytics, University of Applied Sciences and Arts of Coburg, 96450 Coburg, Germany
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22
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Dunst S, Kazimiers T, von Zadow F, Jambor H, Sagner A, Brankatschk B, Mahmoud A, Spannl S, Tomancak P, Eaton S, Brankatschk M. Endogenously tagged rab proteins: a resource to study membrane trafficking in Drosophila. Dev Cell 2015; 33:351-65. [PMID: 25942626 PMCID: PMC4431667 DOI: 10.1016/j.devcel.2015.03.022] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 01/21/2015] [Accepted: 03/29/2015] [Indexed: 11/25/2022]
Abstract
Membrane trafficking is key to the cell biological mechanisms underlying development. Rab GTPases control specific membrane compartments, from core secretory and endocytic machinery to less-well-understood compartments. We tagged all 27 Drosophila Rabs with YFP(MYC) at their endogenous chromosomal loci, determined their expression and subcellular localization in six tissues comprising 23 cell types, and provide this data in an annotated, searchable image database. We demonstrate the utility of these lines for controlled knockdown and show that similar subcellular localization can predict redundant functions. We exploit this comprehensive resource to ask whether a common Rab compartment architecture underlies epithelial polarity. Strikingly, no single arrangement of Rabs characterizes the five epithelia we examine. Rather, epithelia flexibly polarize Rab distribution, producing membrane trafficking architectures that are tissue- and stage-specific. Thus, the core machinery responsible for epithelial polarization is unlikely to rely on polarized positioning of specific Rab compartments.
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Affiliation(s)
- Sebastian Dunst
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
| | - Tom Kazimiers
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany; HHMI Janelia Research Campus, Ashburn, VA 20147, USA
| | - Felix von Zadow
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
| | - Helena Jambor
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
| | - Andreas Sagner
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany; MRC National Institute for Medical Research, London NW7 1AA, UK
| | - Beate Brankatschk
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany; Paul Langerhans Institute, Dresden 01307, Germany
| | - Ali Mahmoud
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
| | - Stephanie Spannl
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
| | - Pavel Tomancak
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany.
| | - Suzanne Eaton
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany.
| | - Marko Brankatschk
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany.
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23
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Zhou J, Liu Z, Yu J, Han X, Fan S, Shao W, Chen J, Qiao R, Xie P. Quantitative Proteomic Analysis Reveals Molecular Adaptations in the Hippocampal Synaptic Active Zone of Chronic Mild Stress-Unsusceptible Rats. Int J Neuropsychopharmacol 2015; 19:pyv100. [PMID: 26364272 PMCID: PMC4772275 DOI: 10.1093/ijnp/pyv100] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 08/31/2015] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND While stressful events are recognized as an important cause of major depressive disorder, some individuals exposed to life stressors maintain normal psychological functioning. The molecular mechanism(s) underlying this phenomenon remain unclear. Abnormal transmission and plasticity of hippocampal synapses have been implied to play a key role in the pathoetiology of major depressive disorder. METHODS A chronic mild stress protocol was applied to separate susceptible and unsusceptible rat subpopulations. Proteomic analysis using an isobaric tag for relative and absolute quantitation coupled with tandem mass spectrometry was performed to identify differential proteins in enriched hippocampal synaptic junction preparations. RESULTS A total of 4318 proteins were quantified, and 89 membrane proteins were present in differential amounts. Of these, SynaptomeDB identified 81 (91%) having a synapse-specific localization. The unbiased profiles identified several candidate proteins within the synaptic junction that may be associated with stress vulnerability or insusceptibility. Subsequent functional categorization revealed that protein systems particularly involved in membrane trafficking at the synaptic active zone exhibited a positive strain as potential molecular adaptations in the unsusceptible rats. Moreover, through STRING and immunoblotting analysis, membrane-associated GTP-bound Rab3a and Munc18-1 appear to coregulate syntaxin-1/SNAP25/VAMP2 assembly at the hippocampal presynaptic active zone of unsusceptible rats, facilitating SNARE-mediated membrane fusion and neurotransmitter release, and may be part of a stress-protection mechanism in actively maintaining an emotional homeostasis. CONCLUSIONS The present results support the concept that there is a range of potential protein adaptations in the hippocampal synaptic active zone of unsusceptible rats, revealing new investigative targets that may contribute to a better understanding of stress insusceptibility.
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Affiliation(s)
- Jian Zhou
- Institute of Neuroscience and the Collaborative Innovation Center for Brain Science, Chongqing Medical University, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Chongqing Key Laboratory of Neurobiology, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China (Drs Liu, Han, Fan, Shao, and Xie)
| | - Zhao Liu
- Institute of Neuroscience and the Collaborative Innovation Center for Brain Science, Chongqing Medical University, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Chongqing Key Laboratory of Neurobiology, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China (Drs Liu, Han, Fan, Shao, and Xie)
| | - Jia Yu
- Institute of Neuroscience and the Collaborative Innovation Center for Brain Science, Chongqing Medical University, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Chongqing Key Laboratory of Neurobiology, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China (Drs Liu, Han, Fan, Shao, and Xie)
| | - Xin Han
- Institute of Neuroscience and the Collaborative Innovation Center for Brain Science, Chongqing Medical University, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Chongqing Key Laboratory of Neurobiology, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China (Drs Liu, Han, Fan, Shao, and Xie)
| | - Songhua Fan
- Institute of Neuroscience and the Collaborative Innovation Center for Brain Science, Chongqing Medical University, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Chongqing Key Laboratory of Neurobiology, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China (Drs Liu, Han, Fan, Shao, and Xie)
| | - Weihua Shao
- Institute of Neuroscience and the Collaborative Innovation Center for Brain Science, Chongqing Medical University, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Chongqing Key Laboratory of Neurobiology, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China (Drs Liu, Han, Fan, Shao, and Xie)
| | - Jianjun Chen
- Institute of Neuroscience and the Collaborative Innovation Center for Brain Science, Chongqing Medical University, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Chongqing Key Laboratory of Neurobiology, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China (Drs Liu, Han, Fan, Shao, and Xie)
| | - Rui Qiao
- Institute of Neuroscience and the Collaborative Innovation Center for Brain Science, Chongqing Medical University, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Chongqing Key Laboratory of Neurobiology, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China (Drs Liu, Han, Fan, Shao, and Xie)
| | - Peng Xie
- Institute of Neuroscience and the Collaborative Innovation Center for Brain Science, Chongqing Medical University, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Chongqing Key Laboratory of Neurobiology, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China (Drs Liu, Han, Fan, Shao, and Xie).
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Tanaka A, De Martino A, Amato A, Montsant A, Mathieu B, Rostaing P, Tirichine L, Bowler C. Ultrastructure and Membrane Traffic During Cell Division in the Marine Pennate Diatom Phaeodactylum tricornutum. Protist 2015; 166:506-21. [PMID: 26386358 PMCID: PMC4710849 DOI: 10.1016/j.protis.2015.07.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2015] [Revised: 06/05/2015] [Accepted: 07/30/2015] [Indexed: 12/14/2022]
Abstract
The marine pennate diatom Phaeodactylum tricornutum has become a model for diatom biology, due to its ease of culture and accessibility to reverse genetics approaches. While several features underlying the molecular mechanisms of cell division have been described, morphological analyses are less advanced than they are in other diatoms. We therefore examined cell ultrastructure changes prior to and during cytokinesis. Following chloroplast division, cleavage furrows are formed at both longitudinal ends of the cell and are accompanied by significant vesicle transport. Although neither spindle nor microtubules were observed, the nucleus appeared to be split by the furrow after duplication of the Golgi apparatus. Finally, centripetal cytokinesis was completed by fusion of the furrows. Additionally, F-actin formed a ring structure and its diameter became smaller, accompanying the ingrowing furrows. To further analyse vesicular transport during cytokinesis, we generated transgenic cells expressing yellow fluorescent protein (YFP) fusions with putative diatom orthologs of small GTPase Sec4 and t-SNARE protein SyntaxinA. Time-lapse observations revealed that SyntaxinA-YFP localization expands from both cell tips toward the center, whereas Sec4-YFP was found in the Golgi and subsequently relocalizes to the future division plane. This work provides fundamental new information about cell replication processes in P. tricornutum.
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Affiliation(s)
- Atsuko Tanaka
- Ecole Normale Supérieure, PSL Research University, Institut de Biologie de l'Ecole Normale Supérieure (IBENS), CNRS UMR 8197, INSERM U1024, 46 rue d'Ulm, F-75005 Paris, France
| | - Alessandra De Martino
- Ecole Normale Supérieure, PSL Research University, Institut de Biologie de l'Ecole Normale Supérieure (IBENS), CNRS UMR 8197, INSERM U1024, 46 rue d'Ulm, F-75005 Paris, France
| | - Alberto Amato
- Ecole Normale Supérieure, PSL Research University, Institut de Biologie de l'Ecole Normale Supérieure (IBENS), CNRS UMR 8197, INSERM U1024, 46 rue d'Ulm, F-75005 Paris, France
| | - Anton Montsant
- Ecole Normale Supérieure, PSL Research University, Institut de Biologie de l'Ecole Normale Supérieure (IBENS), CNRS UMR 8197, INSERM U1024, 46 rue d'Ulm, F-75005 Paris, France
| | - Benjamin Mathieu
- Imaging Platform, Institut de Biologie de l'Ecole Normale Supérieure (IBENS), CNRS UMR8197 INSERM U1024, 46, rue d'Ulm, 75230 Paris Cedex 05, France
| | - Philippe Rostaing
- Neuroscience Section, Institut de Biologie de l'Ecole Normale Supérieure (IBENS), CNRS UMR8197 INSERM U1024, 46, rue d'Ulm, 75230 Paris Cedex 05, France
| | - Leila Tirichine
- Ecole Normale Supérieure, PSL Research University, Institut de Biologie de l'Ecole Normale Supérieure (IBENS), CNRS UMR 8197, INSERM U1024, 46 rue d'Ulm, F-75005 Paris, France
| | - Chris Bowler
- Ecole Normale Supérieure, PSL Research University, Institut de Biologie de l'Ecole Normale Supérieure (IBENS), CNRS UMR 8197, INSERM U1024, 46 rue d'Ulm, F-75005 Paris, France.
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25
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The trials and tubule-ations of Rab6 involvement in Golgi-to-ER retrograde transport. Biochem Soc Trans 2015; 42:1453-9. [PMID: 25233431 DOI: 10.1042/bst20140178] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
In the early secretory pathway, membrane flow in the anterograde direction from the endoplasmic reticulum (ER) to the Golgi complex needs to be tightly co-ordinated with retrograde flow to maintain the size, composition and functionality of these two organelles. At least two mechanisms of transport move material in the retrograde direction: one regulated by the cytoplasmic coatomer protein I complex (COPI), and a second COPI-independent pathway utilizing the small GTP-binding protein Rab6. Although the COPI-independent pathway was discovered 15 years ago, it remains relatively poorly characterized, with only a handful of machinery molecules associated with its operation. One feature that makes this pathway somewhat unusual, and potentially difficult to study, is that the transport carriers predominantly seem to be tubular rather than vesicular in nature. This suggests that the regulatory machinery is likely to be different from that associated with vesicular transport pathways controlled by conventional coat complexes. In the present mini-review, we have highlighted the key experiments that have characterized this transport pathway so far and also have discussed the challenges that lie ahead with respect to its further characterization.
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Castillo-Badillo JA, Sánchez-Reyes OB, Alfonzo-Méndez MA, Romero-Ávila MT, Reyes-Cruz G, García-Sáinz JA. α1B-adrenergic receptors differentially associate with Rab proteins during homologous and heterologous desensitization. PLoS One 2015; 10:e0121165. [PMID: 25799564 PMCID: PMC4370394 DOI: 10.1371/journal.pone.0121165] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 01/28/2015] [Indexed: 11/24/2022] Open
Abstract
Internalization of G protein-coupled receptors can be triggered by agonists or by other stimuli. The process begins within seconds of cell activation and contributes to receptor desensitization. The Rab GTPase family controls endocytosis, vesicular trafficking, and endosomal fusion. Among their remarkable properties is the differential distribution of its members on the surface of various organelles. In the endocytic pathway, Rab 5 controls traffic from the plasma membrane to early endosomes, whereas Rab 4 and Rab 11 regulate rapid and slow recycling from early endosomes to the plasma membrane, respectively. Moreover, Rab 7 and Rab 9 regulate the traffic from late endosomes to lysosomes and recycling to the trans-Golgi. We explore the possibility that α1B-adrenergic receptor internalization induced by agonists (homologous) and by unrelated stimuli (heterologous) could involve different Rab proteins. This possibility was explored by Fluorescence Resonance Energy Transfer (FRET) using cells coexpressing α1B-adrenergic receptors tagged with the red fluorescent protein, DsRed, and different Rab proteins tagged with the green fluorescent protein. It was observed that when α1B-adrenergic receptors were stimulated with noradrenaline, the receptors interacted with proteins present in early endosomes, such as the early endosomes antigen 1, Rab 5, Rab 4, and Rab 11 but not with late endosome markers, such as Rab 9 and Rab 7. In contrast, sphingosine 1-phosphate stimulation induced rapid and transient α1B-adrenergic receptor interaction of relatively small magnitude with Rab 5 and a more pronounced and sustained one with Rab 9; interaction was also observed with Rab 7. Moreover, the GTPase activity of the Rab proteins appears to be required because no FRET was observed when dominant-negative Rab mutants were employed. These data indicate that α1B-adrenergic receptors are directed to different endocytic vesicles depending on the desensitization type (homologous vs. heterologous).
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Affiliation(s)
- Jean A. Castillo-Badillo
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Ap. Postal 70–248, México D.F. 04510, Mexico
| | - Omar B. Sánchez-Reyes
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Ap. Postal 70–248, México D.F. 04510, Mexico
| | - Marco A. Alfonzo-Méndez
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Ap. Postal 70–248, México D.F. 04510, Mexico
| | - M. Teresa Romero-Ávila
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Ap. Postal 70–248, México D.F. 04510, Mexico
| | - Guadalupe Reyes-Cruz
- Departamento de Biología Celular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional-CINVESTAV, Av. Instituto Politécnico Nacional No. 2508, Col. San Pedro Zacatenco, CP 07360, México, D.F., Mexico
| | - J. Adolfo García-Sáinz
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Ap. Postal 70–248, México D.F. 04510, Mexico
- * E-mail:
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Liu SL, Wu QM, Zhang LJ, Wang ZG, Sun EZ, Zhang ZL, Pang DW. Three-dimensional tracking of Rab5- and Rab7-associated infection process of influenza virus. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2014; 10:4746-53. [PMID: 24976105 DOI: 10.1002/smll.201400944] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2014] [Revised: 05/18/2014] [Indexed: 05/15/2023]
Abstract
Three-dimensional (3D) single-particle tracking (SPT) techniques have been widely reported. However, the 3D SPT technique remains poorly used for solving actual biological problems. In this work, a quantum dots (QDs)-based single-particle tracking technique is utilized to explore the Rab5- and Rab7-associated infection behaviors of influenza virus in three dimensions with a set of easily-attained equipment by the fast and accurate centroid method for 3D SPT. The experimental results indicate that Rab5 protein takes part in the virus infection process from the cell periphery to the perinuclear region, while Rab7 protein is mainly involved in the intermittent and confined movements of the virus in the perinuclear region. Evidently, the transition process of the virus-containing vesicles from early to late endosomes might occur during the intermittent movement in the perinuclear region. These findings reveal distinct dynamic behaviors of Rab5- and Rab7-positive endosomes in the course of the intracellular transport of viruses. This work is helpful in understanding the intracellular transport of cargoes.
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Affiliation(s)
- Shu-Lin Liu
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, State Key Laboratory of Virology and Wuhan Institute of Biotechnology, Wuhan University, Wuhan, 430072, P. R. China
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28
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Dhanasekaran S, Jenum S, Stavrum R, Wiker HG, Kenneth J, Vaz M, Doherty TM, Grewal HMS. Effect of non-tuberculous Mycobacteria on host biomarkers potentially relevant for tuberculosis management. PLoS Negl Trop Dis 2014; 8:e3243. [PMID: 25329719 PMCID: PMC4199571 DOI: 10.1371/journal.pntd.0003243] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 09/05/2014] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Non-tuberculous mycobacteria (NTM) are different from Mycobacterium tuberculosis (MTB) both in their ubiquitous environmental distribution and in their reduced capacity to cause disease. While often neglected in favour of other infectious diseases, NTM may interfere with important aspects of TB control and management, namely the efficacy of new anti-tuberculosis (TB) vaccines; the immuno-diagnostic Tuberculin skin test (TST) and QuantiFERON TB Gold In Tube assay (QFTGIT); and immune biomarkers explored for their diagnostic and/or predictive potential. Our objective was therefore to explore host immune biomarkers in children who had NTM isolated from respiratory and/or gastric specimens. METHODOLOGY AND PRINCIPLE FINDINGS The present study was nested within a prospective cohort study of BCG-vaccinated neonates in Southern India. In this setting, immune biomarkers from peripheral blood were analyzed in 210 children aged <3 years evaluated for TB using dual-colour-Reverse-Transcriptase-Multiple-Ligation-dependent-Probe-Amplification (dcRT-MLPA) and Bio-Plex assays. The children were classified based on clinical examination, chest X-rays and mycobacterial culture reports as either: 1) TB disease, 2) NTM present and 3) controls. The study shows a down-regulation of RAB33A (p<0.001) and up-regulation of TGFβ1, IL-2 and IL-6 (all p<0.05) in children with TB disease, and that RAB33A, TGFBR2 and IL-10 (all p<0.05) were differentially expressed in children with NTM present when compared to children that were culture negative for MTB and NTM (controls). CONCLUSIONS AND SIGNIFICANCE Carriage of NTM may reduce the specificity of future diagnostic and predictive immune biomarkers relevant to TB management.
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Affiliation(s)
- S. Dhanasekaran
- Department of Clinical Science, Faculty of Medicine and Dentistry, University of Bergen, Bergen, Norway
| | - Synne Jenum
- Center for Immune Regulation, Rikshospitalet- Radium Hospitalet Medical Centre, University of Oslo, Oslo, Norway
| | - Ruth Stavrum
- Department of Clinical Science, Faculty of Medicine and Dentistry, University of Bergen, Bergen, Norway
| | - Harald G. Wiker
- Department of Clinical Science, Faculty of Medicine and Dentistry, University of Bergen, Bergen, Norway
| | - John Kenneth
- Division of Infectious Diseases, St. John's Research Institute, Koramangala, Bangalore, India
| | - Mario Vaz
- Division of Health & Humanities, St. John's Research Institute, Koramangala, Bangalore, India
| | - T. Mark Doherty
- Department of Clinical Science, Faculty of Medicine and Dentistry, University of Bergen, Bergen, Norway
- GlaxoSmithKline Pharma, Vaccines, Brøndby, Denmark
- * E-mail: (TMD); (HMSG)
| | - Harleen M. S. Grewal
- Department of Clinical Science, Faculty of Medicine and Dentistry, University of Bergen, Bergen, Norway
- Department of Microbiology, Haukeland university hospital, University of Bergen, Bergen, Norway
- * E-mail: (TMD); (HMSG)
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Low YS, Bircham PW, Maass DR, Atkinson PH. Kinetochore genes are required to fully activate secretory pathway expansion in S. cerevisiae under induced ER stress. MOLECULAR BIOSYSTEMS 2014; 10:1790-802. [PMID: 24722431 DOI: 10.1039/c3mb70414a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Basal ER stress occurs when proteins misfold in normal physiological conditions and are corrected by the unfolded protein response (UPR). Elevated ER stress occurs when misfolding is refractory as found in numerous diseases such as atherosclerosis, Type II diabetes and some cancers. In elevated ER stress it is unclear whether cells utilise the same or different networks of genes as in basal levels of ER stress. To probe this question, we used secretory pathway reporters Yip3p-GFP, Erv29p-GFP, Orm2p-GFP and UPREpr-GFP placed on the yeast deletion mutant array (DMA) genetic background. The reporter's expression levels, measured by automated microscopy, at basal versus elevated ER stress induced by the over-expression of CPY* were compared. A novel group of kinetochore genes (CTF19 complex) were found to be uniquely required for full induction of all four ER stress reporters in elevated stress. A follow-up reporter screen was developed by mating the ctf19Δ kinetochore gene deletion strain into the genome-wide XXXp-GFP tagged library then testing with over-expressed CPY*. This screen identified Bcy1p and Bfr1p as possible signalling points that down-regulate the UPR and secretory pathway when kinetochore proteins are absent under elevated stress conditions. Bfr1p appears to be a checkpoint that monitors the integrity of kinetochores at increased levels of ER stress. This study concludes that functional kinetochores are required for full activation of the secretory pathway in elevated ER stress and that the responses to basal and elevated levels of ER stress require different networks of genes.
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Affiliation(s)
- Yee S Low
- School of Biological Sciences, Victoria University of Wellington, Kelburn Parade, Wellington, New Zealand.
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30
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Choi B, Heo JH, Kwon HJ, Lee ES, Sohn S. Tocotrienols enhance melanosome degradation through endosome docking/fusion proteins in B16F10 melanoma cells. Food Funct 2014; 4:1481-8. [PMID: 23995710 DOI: 10.1039/c3fo60289c] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Vitamin E inhibits tyrosinase activity and acts as a melanogenesis inhibitor in epidermal melanocytes in vitro. However, there is no direct evidence indicating that melanosomes are degraded in lysosomes in the presence of vitamin E. To determine whether vitamin E-induced melanosome disintegration is related to the expression of endosome docking/fusion proteins in B16F10 melanoma cells, electron microscopy, reverse transcription-polymerase chain reaction (RT-PCR), and real-time PCR were used to observe the effects of tocomin (α-tocopherols and α,γ,δ-tocotrienols in palm oil) on B16F10 melanoma cells. Melanosomal integrity was lost in lysosomes of B16F10 melanoma cells when treated with tocomin, indicating that tocomin caused the degradation of melanosomes in the lysosomal compartment. RT-PCR and real-time PCR analysis demonstrated mRNA expression of tyrosinase and the endosome docking/fusion proteins (syntaxin7, Rab7, Vps11, Vps16, Vps33, Vps39, and Vps41). Expression of syntaxin7, Vps16, Vps33, and Vps41 mRNA increased significantly in cells treated with tocomin compared with that in controls. These results indicate that the tocomin-induced degradation of melanosomes in the lysosomal compartment occurs with an increase in endosome docking/fusion proteins (syntaxin7, Vps16, Vps33, and Vps41) in cultured B16F10 melanoma cells.
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Affiliation(s)
- Bunsoon Choi
- Laboratory of Cell Biology, Ajou University Institute for Medical Sciences, Suwon 443-721, South Korea.
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Lunn D, Gaddipati SR, Tucker GA, Lycett GW. Null mutants of individual RABA genes impact the proportion of different cell wall components in stem tissue of Arabidopsis thaliana. PLoS One 2013; 8:e75724. [PMID: 24124508 PMCID: PMC3790814 DOI: 10.1371/journal.pone.0075724] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Accepted: 08/21/2013] [Indexed: 12/18/2022] Open
Abstract
In Arabidopsis, and other plants, the RABA GTPases (orthologous to the Rab11a of mammals) have expanded in number and diversity and have been shown to belong to eight sub clades, some of which have been implicated in controlling vesicles that traffic cell wall polymers and enzymes that synthesise or modify them to the cell wall. In order to investigate this, we have investigated whether T-DNA insertion knockouts of individual RABA genes belonging to different sub clades, impact on the composition of the plant cell wall. Single gene knockouts of the RABA1, RABA2 and RABA4 sub clades primarily affected the percentage composition of pectin, cellulose and hemicellulose within the cell wall, respectively, despite having no obvious phenotype in the whole plant. We hypothesise that vesicles carrying specific types of cargoes from the Golgi to the cell surface may be regulated by particular sub types of RABA proteins, a finding that could have wider implications for how trafficking systems work and could be a useful tool in cell wall research and other fields of plant biology.
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Affiliation(s)
- Daniel Lunn
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, United Kingdom
| | - Sanyasi R. Gaddipati
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, United Kingdom
| | - Gregory A. Tucker
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, United Kingdom
| | - Grantley W. Lycett
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, United Kingdom
- * E-mail:
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Abstract
In mammalian testes, the blood-testis barrier (BTB), created by specialized junctions between Sertoli cells near the basement membrane of the seminiferous epithelium, provides an indispensable immune-privileged microenvironment for spermatid development. However, the BTB must experience restructuring during the epithelial cycle to facilitate the transit of preleptotene spermatocytes upon the testosterone-induced new TJ fibrils forming behind these cells, which is intimately related to the extensive dynamics of junction protein complexes between Sertoli cells. As key regulators of protein traffic, Rab GTPases participate in delivery of proteins between distinct cellular sites and cross talk with proteins that constitute tight junction and adherens junction. Using primarily cultured Sertoli cells in vitro with an established tight junction permeability barrier that mimics the BTB in vivo, RAB13 was shown to decrease during the testosterone-induced TJ integrity enhancement, accompanied with an increment in protein kinase A (PKA) activity. Furthermore, knockdown of Rab13 was found to resemble the effect of testosterone on Sertoli cell TJ permeability by reinforcing filamentous actin and occludin distribution at the cell-cell interface and promoting the direct interaction between ZO-1 and occludin. Interestingly, the effects of testosterone and Rab13 knockdown on Sertoli cell epithelium were revealed to be antagonized by PKA activity inhibition. In summary, RAB13 serves as a regulatory component in the assembly and restructuring of the TJ fibrils between adjacent Sertoli cells.
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Affiliation(s)
- Wenhui Su
- Department of Biochemistry and Molecular Biology, Basic Medical College.
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Dhanasekaran S, Jenum S, Stavrum R, Ritz C, Faurholt-Jepsen D, Kenneth J, Vaz M, Grewal HMS, Doherty TM. Identification of biomarkers for Mycobacterium tuberculosis infection and disease in BCG-vaccinated young children in Southern India. Genes Immun 2013; 14:356-64. [DOI: 10.1038/gene.2013.26] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 03/04/2013] [Accepted: 04/01/2013] [Indexed: 11/09/2022]
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Militello RD, Munafó DB, Berón W, López LA, Monier S, Goud B, Colombo MI. Rab24 is required for normal cell division. Traffic 2013; 14:502-18. [PMID: 23387408 DOI: 10.1111/tra.12057] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2012] [Revised: 02/04/2013] [Accepted: 02/06/2013] [Indexed: 12/18/2022]
Abstract
Rab24 is an atypical member of the Rab GTPase family whose distribution in interphase cells has been characterized; however, its function remains largely unknown. In this study, we have analyzed the distribution of Rab24 throughout cell division. We have observed that Rab24 was located at the mitotic spindle in metaphase, at the midbody during telophase and in the furrow during cytokinesis. We have also observed partial co-localization of Rab24 and tubulin and demonstrated its association to microtubules. Interestingly, more than 90% of transiently transfected HeLa cells with Rab24 presented abnormal nuclear connections (i.e., chromatin bridges). Furthermore, in CHO cells stably transfected with GFP-Rab24wt, we observed a large percentage of binucleated and multinucleated cells. In addition, these cells presented an extremely large size and multiple failures in mitosis, as aberrant spindle formation (metaphase), delayed chromosomes (telophase) and multiple cytokinesis. A marked increase in binucleated, multinucleated and multilobulated nucleus formation was observed in HeLa cells depleted of Rab24. We also present evidence that a fraction of Rab24 associates with microtubules. In addition, Rab24 knock down resulted in misalignment of chromosomes and abnormal spindle formation in metaphase leading to the appearance of delayed chromosomes during late telophase and failures in cytokinesis. Our findings suggest that an adequate level of Rab24 is necessary for normal cell division. In summary, Rab24 modulates several mitotic events, including chromosome segregation and cytokinesis, perhaps through the interaction with microtubules.
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Affiliation(s)
- Rodrigo D Militello
- Laboratorio de Biología Celular y Molecular- Instituto de Histología y Embriología (IHEM), Facultad de Ciencias Médicas, Universidad Nacional de Cuyo-CONICET, Mendoza, Argentina
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Adung'a VO, Field MC. TbFRP, a novel FYVE-domain containing phosphoinositide-binding Ras-like GTPase from trypanosomes. Exp Parasitol 2012; 133:255-64. [PMID: 23220323 PMCID: PMC3593210 DOI: 10.1016/j.exppara.2012.11.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Accepted: 11/15/2012] [Indexed: 01/06/2023]
Abstract
Ras-like small GTPases are regulatory proteins that control multiple aspects of cellular function, and are particularly prevalent in vesicular transport. A proportion of GTPase paralogs appear restricted to certain eukaryote lineages, suggesting roles specific to a restricted lineage, and hence potentially reflecting adaptation to individual lifestyles or ecological niche. Here we describe the role of a GTPase, TbFRP, a FYVE domain N-terminally fused to a Ras-like GTPase, originally identified in Trypanosoma brucei. As FYVE-domains specifically bind phosphoinositol 3-phosphate (PI3P), which associates with endosomes, we suggest that TbFRP may unite phosphoinositide and small G protein endosomal signaling in trypanosomatids. TbFRP orthologs are present throughout the Euglenazoa suggesting that FRP has functions throughout the group. We show that the FYVE domain of TbFRP is functional in PI3P-dependent membrane targeting and localizes at the endosomal region. Further, while TbFRP is apparently non-essential, knockdown and immunochemical evidence indicates that TbFRP is rapidly cleaved upon synthesis, releasing the GTPase and FYVE-domains. Finally, TbFRP expression at both mRNA and protein levels is cell density-dependent. Together, these data suggest that TbFRP is an endocytic GTPase with a highly unusual mechanism of action that involves proteolysis of the nascent protein and membrane targeting via PI3P.
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Affiliation(s)
- Vincent O Adung'a
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK
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Delazari dos Santos L, Aparecido dos Santos Pinto JR, Ribeiro da Silva Menegasso A, Menezes Saidemberg D, Caviquioli Garcia AM, Sergio Palma M. Proteomic profiling of the molecular targets of interactions of the mastoparan peptide Protopolybia MP-III at the level of endosomal membranes from rat mast cells. Proteomics 2012; 12:2682-93. [DOI: 10.1002/pmic.201200030] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2012] [Revised: 04/13/2012] [Accepted: 04/16/2012] [Indexed: 01/30/2023]
Affiliation(s)
- Lucilene Delazari dos Santos
- Center for the Study of Venoms and Venomous Animals (CEVAP); University of São Paulo State (UNESP); Botucatu SP Brazil
- Instituto Nacional de Ciência e Tecnologia (INCT) em Imunologia/iii; Rio Claro SP Brazil
| | - José Roberto Aparecido dos Santos Pinto
- Instituto Nacional de Ciência e Tecnologia (INCT) em Imunologia/iii; Rio Claro SP Brazil
- Institute of Biosciences/Department of Biology; Center for the Study of Social Insects; University of São Paulo State (UNESP); Rio Claro SP Brazil
| | - Anally Ribeiro da Silva Menegasso
- Instituto Nacional de Ciência e Tecnologia (INCT) em Imunologia/iii; Rio Claro SP Brazil
- Institute of Biosciences/Department of Biology; Center for the Study of Social Insects; University of São Paulo State (UNESP); Rio Claro SP Brazil
| | - Daniel Menezes Saidemberg
- Instituto Nacional de Ciência e Tecnologia (INCT) em Imunologia/iii; Rio Claro SP Brazil
- Institute of Biosciences/Department of Biology; Center for the Study of Social Insects; University of São Paulo State (UNESP); Rio Claro SP Brazil
| | - Ana Maria Caviquioli Garcia
- Instituto Nacional de Ciência e Tecnologia (INCT) em Imunologia/iii; Rio Claro SP Brazil
- Institute of Biosciences/Department of Biology; Center for the Study of Social Insects; University of São Paulo State (UNESP); Rio Claro SP Brazil
| | - Mario Sergio Palma
- Instituto Nacional de Ciência e Tecnologia (INCT) em Imunologia/iii; Rio Claro SP Brazil
- Institute of Biosciences/Department of Biology; Center for the Study of Social Insects; University of São Paulo State (UNESP); Rio Claro SP Brazil
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Crystal structure of Rab6A'(Q72L) mutant reveals unexpected GDP/Mg²⁺ binding with opened GTP-binding domain. Biochem Biophys Res Commun 2012; 424:269-73. [PMID: 22750005 DOI: 10.1016/j.bbrc.2012.06.102] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Accepted: 06/20/2012] [Indexed: 01/14/2023]
Abstract
The Ras small G protein-superfamily is a family of GTP hydrolases whose activity is regulated by GTP/GDP binding states. Rab6A, a member of the Ras superfamily, is involved in the regulation of vesicle trafficking, which is critical for endocytosis, biosynthesis, secretion, cell differentiation and cell growth. Rab6A exists in two isoforms, termed RabA and Rab6A'. Substitution of Gln72 to Leu72 (Q72L) at Rab6 family blocks GTP hydrolysis activity and this mutation usually causes the Rab6 protein to be constitutively in an active form. Here, we report the crystal structure of the human Rab6A'(Q72L) mutant form at 1.9Å resolution. Unexpectedly, we found that Rab6A'(Q72L) possesses GDP/Mg(2+) in the GTP binding pockets, which is formed by a flexible switch I and switch II. Large conformational changes were also detected in the switch I and switch II regions. Our structure revealed that the non-hydrolysable, constitutively active form of Rab6A' can accommodate GDP/Mg(2+) in the open conformation.
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Orthobunyavirus entry into neurons and other mammalian cells occurs via clathrin-mediated endocytosis and requires trafficking into early endosomes. J Virol 2012; 86:7988-8001. [PMID: 22623766 DOI: 10.1128/jvi.00140-12] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
La Crosse virus (LACV) is a leading cause of pediatric encephalitis and aseptic meningitis in the midwestern and southern United States, where it is considered an emerging human pathogen. No specific therapies or vaccines are available for LACV or any other orthobunyaviruses. Inhibition of LACV entry into cells is a potential target for therapeutic intervention, but this approach is limited by our current knowledge of the entry process. Here, we determined that clathrin-mediated endocytosis is the primary mechanism of orthobunyavirus entry and identified key cellular factors in this process. First, we demonstrated that LACV colocalized with clathrin shortly after infection in HeLa cells; we then confirmed the functional requirement of dynamin- and clathrin-mediated endocytosis for orthobunyavirus entry using several independent assays and, importantly, extended these findings to primary neuronal cultures. We also determined that macropinocytosis and caveolar endocytosis, both established routes of virus entry, are not critical for cellular entry of LACV. Moreover, we demonstrated that LACV infection is dependent on Rab5, which plays an important regulatory role in early endosomes, but not on Rab7, which is associated with late endosomes. These findings provide the first description of bunyavirus entry into cells of the central nervous system, where infection can cause severe neurological disease, and will aid in the design and development of antivirals and therapeutics that may be useful in the treatment of LACV and, more broadly, arboviral infections of the central nervous system.
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Fernández-Irigoyen J, Corrales FJ, Santamaría E. Proteomic atlas of the human olfactory bulb. J Proteomics 2012; 75:4005-16. [PMID: 22609191 DOI: 10.1016/j.jprot.2012.05.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Revised: 05/04/2012] [Accepted: 05/07/2012] [Indexed: 11/28/2022]
Abstract
The olfactory bulb (OB) is the first site for the processing of olfactory information in the brain and its deregulation is associated with neurodegenerative disorders. Although different efforts have been made to characterize the human brain proteome in depth, the protein composition of the human OB remains largely unexplored. We have performed a comprehensive analysis of the human OB proteome employing protein and peptide fractionation methods followed by LC-MS/MS, identifying 1529 protein species, corresponding to 1466 unique proteins, which represents a 7-fold increase in proteome coverage with respect to previous OB proteome descriptions from translational models. Bioinformatic analyses revealed that protein components of the OB participated in a plethora of biological process highlighting hydrolase and phosphatase activities and nucleotide and RNA binding activities. Interestingly, 631 OB proteins identified were not previously described in protein datasets derived from large-scale Human Brain Proteome Project (HBPP) studies. In particular, a subset of these differential proteins was mainly involved in axon guidance, opioid signaling, neurotransmitter receptor binding, and synaptic plasticity. Taken together, these results increase our knowledge about the molecular composition of the human OB and may be useful to understand the molecular basis of the olfactory system and the etiology of its disorders.
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Javier-Reyna R, Hernández-Ramírez V, González-Robles A, Galván-Mendoza I, Osorio-Trujillo C, Talamás-Rohana P. Rab7 and actin cytoskeleton participate during mobilization of β1EHFNR in fibronectin-stimulated Entamoeba histolyticatrophozoites. Microsc Res Tech 2011; 75:285-93. [DOI: 10.1002/jemt.21056] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Accepted: 06/12/2011] [Indexed: 01/12/2023]
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Huang WR, Wang YC, Chi PI, Wang L, Wang CY, Lin CH, Liu HJ. Cell entry of avian reovirus follows a caveolin-1-mediated and dynamin-2-dependent endocytic pathway that requires activation of p38 mitogen-activated protein kinase (MAPK) and Src signaling pathways as well as microtubules and small GTPase Rab5 protein. J Biol Chem 2011; 286:30780-30794. [PMID: 21705803 DOI: 10.1074/jbc.m111.257154] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Very little is known about the mechanism of cell entry of avian reovirus (ARV). The aim of this study was to explore the mechanism of ARV entry and subsequent infection. Cholesterol mainly affected the early steps of the ARV life cycle, because the presence of cholesterol before and during viral adsorption greatly blocked ARV infectivity. Although we have demonstrated that ARV facilitating p38 MAPK is beneficial for virus replication, its mechanism remains unknown. Here, we show that ARV-induced phosphorylation of caveolin-1 (Tyr(14)), dynamin-2 expression, and Rac1 activation through activation of p38 MAPK and Src in the early stage of the virus life cycle is beneficial for virus entry and productive infection. The strong inhibition by dynasore, a specific inhibitor of dynamin-2, and depletion of endogenous caveolin-1 or dynamin-2 by siRNAs as well as the caveolin-1 colocalization study implicate caveolin-1-mediated and dynamin-2-dependent endocytosis as a significant avenue of ARV entry. By means of pharmacological inhibitors, dominant negative mutants, and siRNA of various cellular proteins and signaling molecules, phosphorylation of caveolin-1, dynamin-2 expression, and Rac1 activation were suppressed, suggesting that by orchestrating p38 MAPK, Src, and Rac1 signaling cascade in the target cells, ARV creates an appropriate intracellular environment facilitating virus entry and productive infection. Furthermore, disruption of microtubules, Rab5, or endosome acidification all inhibited ARV infection, suggesting that microtubules and small GTPase Rab5, which regulate transport to early endosome, are crucial for survival of ARV and that exposure of the virus to acidic pH is required for productive infection.
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Affiliation(s)
- Wei R Huang
- Institute of Molecular Biology, National Chung Ching University, Taichung 402
| | - Ying C Wang
- Institute of Molecular Biology, National Chung Ching University, Taichung 402; Graduate Institute of Biotechnology, National Pingtung University of Science and Technology, Pingtung 912
| | - Pei I Chi
- Institute of Molecular Biology, National Chung Ching University, Taichung 402; Graduate Institute of Biotechnology, National Pingtung University of Science and Technology, Pingtung 912
| | - Lai Wang
- Institute of Molecular Biology, National Chung Ching University, Taichung 402
| | - Chi Y Wang
- Department of Veterinary Medicine, National Chung Ching University, Taichung 402
| | - Chi H Lin
- Institute of Microbiology and Immunology, National Yang-Ming University, Taipei 11221, Taiwan
| | - Hung J Liu
- Institute of Molecular Biology, National Chung Ching University, Taichung 402.
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Saba LM, Bennett B, Hoffman PL, Barcomb K, Ishii T, Kechris K, Tabakoff B. A systems genetic analysis of alcohol drinking by mice, rats and men: influence of brain GABAergic transmission. Neuropharmacology 2011; 60:1269-80. [PMID: 21185315 PMCID: PMC3079014 DOI: 10.1016/j.neuropharm.2010.12.019] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Revised: 12/01/2010] [Accepted: 12/15/2010] [Indexed: 11/19/2022]
Abstract
Genetic influences on the predisposition to complex behavioral or physiological traits can reflect genetic polymorphisms that lead to altered gene product function, and/or variations in gene expression levels. We have explored quantitative variations in an animal's alcohol consumption, using a genetical genomic/phenomic approach. In our studies, gene expression is correlated with amount of alcohol consumed, and genomic regions that regulate the alcohol consumption behavior and the quantitative levels of gene expression (behavioral and expression quantitative trait loci [QTL]) are determined and used as a filter to identify candidate genes predisposing the behavior. We determined QTLs for alcohol consumption using the LXS panel of recombinant inbred mice. We then identified genes that were: 1) differentially expressed between five high and five low alcohol-consuming lines or strains of mice; and 2) were physically located in, or had an expression QTL (eQTL) within the alcohol consumption QTLs. Comparison of mRNA and protein levels in brains of high and low alcohol consuming mice led us to a bioinformatic examination of potential regulation by microRNAs of an identified candidate transcript, Gnb1 (G protein beta subunit 1). We combined our current analysis with our earlier work identifying candidate genes for the alcohol consumption trait in mice, rats and humans. Our overall analysis leads us to postulate that the activity of the GABAergic system, and in particular GABA release and GABA receptor trafficking and signaling, which involves G protein function, contributes significantly to genetic variation in the predisposition to varying levels of alcohol consumption. This article is part of a Special Issue entitled 'Trends in neuropharmacology: in memory of Erminio Costa'.
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Affiliation(s)
- Laura M. Saba
- University of Colorado Denver School of Medicine, PO Box 6511, MS 8303, Aurora, CO 80045 USA; , , , , ,
| | - Beth Bennett
- University of Colorado Denver School of Medicine, PO Box 6511, MS 8303, Aurora, CO 80045 USA; , , , , ,
| | - Paula L. Hoffman
- University of Colorado Denver School of Medicine, PO Box 6511, MS 8303, Aurora, CO 80045 USA; , , , , ,
| | - Kelsey Barcomb
- University of Colorado Denver School of Medicine, PO Box 6511, MS 8303, Aurora, CO 80045 USA; , , , , ,
| | - Takao Ishii
- University of Colorado Denver School of Medicine, PO Box 6511, MS 8303, Aurora, CO 80045 USA; , , , , ,
| | - Katerina Kechris
- Colorado School of Public Health, Campus Box B119, Aurora, CO 80045 USA,
| | - Boris Tabakoff
- University of Colorado Denver School of Medicine, PO Box 6511, MS 8303, Aurora, CO 80045 USA; , , , , ,
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Subcellular trafficking of the substrate transporters GLUT4 and CD36 in cardiomyocytes. Cell Mol Life Sci 2011; 68:2525-38. [PMID: 21547502 PMCID: PMC3134709 DOI: 10.1007/s00018-011-0690-x] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2011] [Revised: 04/01/2011] [Accepted: 04/12/2011] [Indexed: 12/16/2022]
Abstract
Cardiomyocytes use glucose as well as fatty acids for ATP production. These substrates are transported into the cell by glucose transporter 4 (GLUT4) and the fatty acid transporter CD36. Besides being located at the sarcolemma, GLUT4 and CD36 are stored in intracellular compartments. Raised plasma insulin concentrations and increased cardiac work will stimulate GLUT4 as well as CD36 to translocate to the sarcolemma. As so far studied, signaling pathways that regulate GLUT4 translocation similarly affect CD36 translocation. During the development of insulin resistance and type 2 diabetes, CD36 becomes permanently localized at the sarcolemma, whereas GLUT4 internalizes. This juxtaposed positioning of GLUT4 and CD36 is important for aberrant substrate uptake in the diabetic heart: chronically increased fatty acid uptake at the expense of glucose. To explain the differences in subcellular localization of GLUT4 and CD36 in type 2 diabetes, recent research has focused on the role of proteins involved in trafficking of cargo between subcellular compartments. Several of these proteins appear to be similarly involved in both GLUT4 and CD36 translocation. Others, however, have different roles in either GLUT4 or CD36 translocation. These trafficking components, which are differently involved in GLUT4 or CD36 translocation, may be considered novel targets for the development of therapies to restore the imbalanced substrate utilization that occurs in obesity, insulin resistance and diabetic cardiomyopathy.
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Peng J, Ilarslan H, Wurtele ES, Bassham DC. AtRabD2b and AtRabD2c have overlapping functions in pollen development and pollen tube growth. BMC PLANT BIOLOGY 2011; 11:25. [PMID: 21269510 PMCID: PMC3040128 DOI: 10.1186/1471-2229-11-25] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2010] [Accepted: 01/26/2011] [Indexed: 05/18/2023]
Abstract
BACKGROUND Rab GTPases are important regulators of endomembrane trafficking, regulating exocytosis, endocytosis and membrane recycling. Many Rab-like proteins exist in plants, but only a subset have been functionally characterized. RESULTS Here we report that AtRabD2b and AtRabD2c play important roles in pollen development, germination and tube elongation. AtrabD2b and AtrabD2c single mutants have no obvious morphological changes compared with wild-type plants across a variety of growth conditions. An AtrabD2b/2c double mutant is also indistinguishable from wild-type plants during vegetative growth; however its siliques are shorter than those in wild-type plants. Compared with wild-type plants, AtrabD2b/2c mutants produce deformed pollen with swollen and branched pollen tube tips. The shorter siliques in the AtrabD2b/2c double mutant were found to be primarily due to the pollen defects. AtRabD2b and AtRabD2c have different but overlapping expression patterns, and they are both highly expressed in pollen. Both AtRabD2b and AtRabD2c protein localize to Golgi bodies. CONCLUSIONS These findings support a partially redundant role for AtRabD2b and AtRabD2c in vesicle trafficking during pollen tube growth that cannot be fulfilled by the remaining AtRabD family members.
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Affiliation(s)
- Jianling Peng
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA 50010, USA
| | - Hilal Ilarslan
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA 50010, USA
| | - Eve Syrkin Wurtele
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA 50010, USA
| | - Diane C Bassham
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA 50010, USA
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45
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Ward BM. The taking of the cytoskeleton one two three: how viruses utilize the cytoskeleton during egress. Virology 2011; 411:244-50. [PMID: 21241997 PMCID: PMC3049855 DOI: 10.1016/j.virol.2010.12.024] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Accepted: 12/04/2010] [Indexed: 11/30/2022]
Abstract
The final assembly of nonlytic envelope viruses requires the coordinated transport of either subviral particles or fully formed virions to the plasma membrane for release from the cell. Recent research has delved into the mechanisms viruses employ to hijack the host cell's cytoskeletal system for active transport to the site of final assembly and release. This review will look at recent findings that relate to the transport of virions to the cell periphery and out of the cell.
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Affiliation(s)
- Brian M Ward
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA.
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Moore ER, Mead DJ, Dooley CA, Sager J, Hackstadt T. The trans-Golgi SNARE syntaxin 6 is recruited to the chlamydial inclusion membrane. MICROBIOLOGY-SGM 2010; 157:830-838. [PMID: 21109560 PMCID: PMC3081085 DOI: 10.1099/mic.0.045856-0] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Chlamydia trachomatis is an obligate intracellular pathogen that replicates within a parasitophorous vacuole termed an inclusion. The chlamydial inclusion is isolated from the endocytic pathway but fusogenic with Golgi-derived exocytic vesicles containing sphingomyelin and cholesterol. Sphingolipids are incorporated into the chlamydial cell wall and are considered essential for chlamydial development and viability. The mechanisms by which chlamydiae obtain eukaryotic lipids are poorly understood but require chlamydial protein synthesis and presumably modification of the inclusion membrane to initiate this interaction. A polarized cell model of chlamydial infection has demonstrated that chlamydiae preferentially intercept basolaterally directed, sphingomyelin-containing exocytic vesicles. Here we examine the localization and potential function of trans-Golgi and/or basolaterally associated soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins in chlamydia-infected cells. The trans-Golgi SNARE protein syntaxin 6 is recruited to the chlamydial inclusion in a manner that requires chlamydial protein synthesis and is conserved among all chlamydial species examined. The localization of syntaxin 6 to the chlamydial inclusion requires a tyrosine motif or plasma membrane retrieval signal (YGRL). Thus in addition to expression of at least two inclusion membrane proteins that contain SNARE-like motifs, chlamydiae also actively recruit eukaryotic SNARE-family proteins.
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Affiliation(s)
- Elizabeth R Moore
- Host-Parasite Interactions Section, Laboratory of Intracellular Parasites, National Institute of Allergy and Infectious Diseases, Rocky Mountain Laboratories, 903 South 4th Street, Hamilton, MT 59840, USA
| | - David J Mead
- Host-Parasite Interactions Section, Laboratory of Intracellular Parasites, National Institute of Allergy and Infectious Diseases, Rocky Mountain Laboratories, 903 South 4th Street, Hamilton, MT 59840, USA
| | - Cheryl A Dooley
- Host-Parasite Interactions Section, Laboratory of Intracellular Parasites, National Institute of Allergy and Infectious Diseases, Rocky Mountain Laboratories, 903 South 4th Street, Hamilton, MT 59840, USA
| | - Janet Sager
- Host-Parasite Interactions Section, Laboratory of Intracellular Parasites, National Institute of Allergy and Infectious Diseases, Rocky Mountain Laboratories, 903 South 4th Street, Hamilton, MT 59840, USA
| | - Ted Hackstadt
- Host-Parasite Interactions Section, Laboratory of Intracellular Parasites, National Institute of Allergy and Infectious Diseases, Rocky Mountain Laboratories, 903 South 4th Street, Hamilton, MT 59840, USA
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Doherty TM, Wallis RS, Zumla A. Biomarkers of disease activity, cure, and relapse in tuberculosis. Clin Chest Med 2010; 30:783-96, x. [PMID: 19925967 DOI: 10.1016/j.ccm.2009.08.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The changing face of tuberculosis, with epidemics fueled by HIV and urbanization in much of the world and a relative increase in the importance of latent tuberculosis as a source of cases in the more economically developed countries, has led to a demand for more robust, clinically applicable diagnostic tools. As a result, research aiming to identify biomarkers of Mycobacterium tuberculosis infection and disease has flourished. This article discusses the most recent findings of that work.
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Affiliation(s)
- T Mark Doherty
- Department of Infectious Disease Immunology, Statens Serum Institute, Artillerivej 5, 2300 København S, Denmark.
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Geiger A, Hirtz C, Bécue T, Bellard E, Centeno D, Gargani D, Rossignol M, Cuny G, Peltier JB. Exocytosis and protein secretion in Trypanosoma. BMC Microbiol 2010; 10:20. [PMID: 20102621 PMCID: PMC3224696 DOI: 10.1186/1471-2180-10-20] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2009] [Accepted: 01/26/2010] [Indexed: 01/07/2023] Open
Abstract
Background Human African trypanosomiasis is a lethal disease caused by the extracellular parasite Trypanosoma brucei. The proteins secreted by T. brucei inhibit the maturation of dendritic cells and their ability to induce lymphocytic allogenic responses. To better understand the pathogenic process, we combined different approaches to characterize these secreted proteins. Results Overall, 444 proteins were identified using mass spectrometry, the largest parasite secretome described to date. Functional analysis of these proteins revealed a strong bias toward folding and degradation processes and to a lesser extent toward nucleotide metabolism. These features were shared by different strains of T. brucei, but distinguished the secretome from published T. brucei whole proteome or glycosome. In addition, several proteins had not been previously described in Trypanosoma and some constitute novel potential therapeutic targets or diagnostic markers. Interestingly, a high proportion of these secreted proteins are known to have alternative roles once secreted. Furthermore, bioinformatic analysis showed that a significant proportion of proteins in the secretome lack transit peptide and are probably not secreted through the classical sorting pathway. Membrane vesicles from secretion buffer and infested rat serum were purified on sucrose gradient and electron microscopy pictures have shown 50- to 100-nm vesicles budding from the coated plasma membrane. Mass spectrometry confirmed the presence of Trypanosoma proteins in these microvesicles, showing that an active exocytosis might occur beyond the flagellar pocket. Conclusions This study brings out several unexpected features of the secreted proteins and opens novel perspectives concerning the survival strategy of Trypanosoma as well as possible ways to control the disease. In addition, concordant lines of evidence support the original hypothesis of the involvement of microvesicle-like bodies in the survival strategy allowing Trypanosoma to exchange proteins at least between parasites and/or to manipulate the host immune system.
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Affiliation(s)
- Anne Geiger
- UMR 177, IRD-CIRAD, CIRAD TA A-17/G, Campus International de Baillarguet, 34398 Montpellier Cedex 5, France.
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Abstract
PURPOSE OF REVIEW Every year, over 8 million people develop tuberculosis and nearly 1.8 million die from it, despite extensive vaccination and drug treatment programmes. It is increasingly recognized that the diagnosis of tuberculosis, which relies heavily on century-old techniques, is one of the weakest links in the chain of tuberculosis control, hampering not just treatment but also the development of new drugs and vaccines. As a result, recent years have seen the initiation of large-scale studies aiming to identify biomarkers of Mycobacterium tuberculosis infection and disease. This review discusses initial results and future prospects for that work. RECENT FINDINGS The key finding from recent work has been that no one factor seems able to explain the complex course of Mycobacterium tuberculosis infection. Multifactorial analyses have identified a variety of genes and proteins, mostly involved in bacterial persistence or host responses, that offer promise as biomarkers for different disease stages. SUMMARY The challenge now is to validate the suggested biomarkers being described and then reduce them to clinical practice. If this can be done, it offers the possibility of greatly improved clinical management of tuberculosis, allowing segregation of patients and contacts into appropriate treatment regimens.
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Li J, Nie Y, Dang X, Liang A, Chai B, Wang W. Characterization of a Rab11 homologue, EoRab11a, in Euplotes octocarinatus. FEMS Microbiol Lett 2009; 292:222-30. [PMID: 19187203 DOI: 10.1111/j.1574-6968.2009.01485.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Rab GTPases are crucial in the regulation of intracellular vesicular trafficking. A novel Rab GTPase gene, EoRab11a (GenBank accession no. EF061065), was isolated and identified from Euplotes octocarinatus cells in this study. It contains an ORF of 696-bp nucleotides, encoding 231 amino acids with a calculated molecular weight of 26.8 kDa. Alignment of EoRab11a with other Rab11 proteins from other eukaryotes demonstrated that these proteins shared 53-61% identity at the amino acid level. The recombinant EoRab11a was expressed in Escherichia coli and purified by immobilized metal chelate affinity chromatography and iron chromatography. The GTPase activity of EoRab11a was 0.0024 min(-1) detected by HPLC at 30 degrees C. Three mutations were generated at amino acids Ser21 and Gly22 positions in the G1 domain of EoRab11a. All three mutants, S21P, S21G and G22R, increased the GTPase activity in vitro. Immunofluorescence microscopy results indicated that EoRab11a was localized on the phagosomal membrane during phagocytosis of E. octocarinatus. These data show that EoRab11a possesses GTP hydrolysis activity and may participate in vesicle transport events during phagocytosis of E. octocarinatus.
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Affiliation(s)
- Jiangjiao Li
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan, Shanxi, China
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