1
|
Bonavita R, Scerra G, Di Martino R, Nuzzo S, Polishchuk E, Di Gennaro M, Williams SV, Caporaso MG, Caiazza C, Polishchuk R, D’Agostino M, Fleming A, Renna M. The HSPB1-p62/SQSTM1 functional complex regulates the unconventional secretion and transcellular spreading of the HD-associated mutant huntingtin protein. Hum Mol Genet 2023; 32:2269-2291. [PMID: 36971475 PMCID: PMC10321397 DOI: 10.1093/hmg/ddad047] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 03/06/2023] [Accepted: 03/23/2023] [Indexed: 07/20/2023] Open
Abstract
Conformational diseases, such as Alzheimer, Parkinson and Huntington diseases, are part of a common class of neurological disorders characterized by the aggregation and progressive accumulation of proteins bearing aberrant conformations. Huntington disease (HD) has autosomal dominant inheritance and is caused by mutations leading to an abnormal expansion in the polyglutamine (polyQ) tract of the huntingtin (HTT) protein, leading to the formation of HTT inclusion bodies in neurons of affected patients. Interestingly, recent experimental evidence is challenging the conventional view by which the disease pathogenesis is solely a consequence of the intracellular accumulation of mutant protein aggregates. These studies reveal that transcellular transfer of mutated huntingtin protein is able to seed oligomers involving even the wild-type (WT) forms of the protein. To date, there is still no successful strategy to treat HD. Here, we describe a novel functional role for the HSPB1-p62/SQSTM1 complex, which acts as a cargo loading platform, allowing the unconventional secretion of mutant HTT by extracellular vesicles. HSPB1 interacts preferentially with polyQ-expanded HTT compared with the WT protein and affects its aggregation. Furthermore, HSPB1 levels correlate with the rate of mutant HTT secretion, which is controlled by the activity of the PI3K/AKT/mTOR signalling pathway. Finally, we show that these HTT-containing vesicular structures are biologically active and able to be internalized by recipient cells, therefore providing an additional mechanism to explain the prion-like spreading properties of mutant HTT. These findings might also have implications for the turn-over of other disease-associated, aggregation-prone proteins.
Collapse
Affiliation(s)
| | | | - R Di Martino
- Institute for Endocrinology and Experimental Oncology “G. Salvatore,” National Research Council, 80131 Naples, Italy
- Institute of Biochemistry and Cell Biology, National Research Council, 80131 Naples, Italy
| | - S Nuzzo
- IRCCS SYNLAB SDN, 80143 Naples, Italy
| | - E Polishchuk
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
| | - M Di Gennaro
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples “Federico II”, 80131 Naples, Italy
| | - S V Williams
- Department of Physiology, Development and Neuroscience, University of Cambridge, CB2 3DY Cambridge, UK
| | - M G Caporaso
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples “Federico II”, 80131 Naples, Italy
| | - C Caiazza
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples “Federico II”, 80131 Naples, Italy
| | - R Polishchuk
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
| | - M D’Agostino
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples “Federico II”, 80131 Naples, Italy
| | - A Fleming
- Department of Physiology, Development and Neuroscience, University of Cambridge, CB2 3DY Cambridge, UK
| | - M Renna
- To whom correspondence should be addressed at: Department of Molecular Medicine and Medical Biotechnologies, School of Medicine, University of Naples “Federico II”, Via S. Pansini, 5, Building 19, Corpi Bassi Sud (I floor), 80131 Naples, Italy. Tel: +39 081/7463623, Fax: +39 081-7463205;
| |
Collapse
|
2
|
Kunishige R, Murata M, Kano F. Targeted protein degradation by Trim-Away using cell resealing coupled with microscopic image-based quantitative analysis. Front Cell Dev Biol 2022; 10:1027043. [PMID: 36601537 PMCID: PMC9806799 DOI: 10.3389/fcell.2022.1027043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Accepted: 11/28/2022] [Indexed: 12/23/2022] Open
Abstract
"Trim-Away" technology enables rapid degradation of endogenous proteins without prior modification of protein-coding genes or mRNAs through delivery of antibodies that target proteins of interest. Although this approach can be readily applied to almost any cytosolic protein, strategies for cytosolic antibody delivery have been limited to microinjection or electroporation, which require skill-dependent operation or specialized equipment. Thus, the development of antibody delivery methods that are convenient, scalable, and preferably do not require detachment of adherent cells is required to extend the versatility of the Trim-Away method. Here, we developed a cell resealing technique optimized for Trim-Away degradation, which uses the pore-forming toxin streptolysin O (SLO) to permeabilize the cell membrane and delivered the antibodies of interest into HEK293T, HeLa, and HK-2 cell lines. We demonstrated the ability of Trim-Away protein degradation using IKKα and mTOR as targets, and we showed the availability of the developed system in antibody screening for the Trim-Away method. Furthermore, we effectively coupled Trim-Away with cyclic immunofluorescence and microscopic image-based analysis, which enables single-cell multiplexed imaging analysis. Taking advantage of this new analysis strategy, we were able to compensate for low signal-to-noise due to cell-to-cell variation, which occurs in the Trim-Away method because of the heterogenous contents of the introduced antibody, target protein, and TRIM21 in individual cells. Therefore, the reported cell resealing technique coupled with microscopic image analysis enables Trim-Away users to elucidate target protein function and the effects of target protein degradation on various cellular functions in a more quantitative and precise manner.
Collapse
Affiliation(s)
- Rina Kunishige
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan,Multimodal Cell Analysis Collaborative Research Cluster, Tokyo Institute of Technology, Yokohama, Japan
| | - Masayuki Murata
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan,Multimodal Cell Analysis Collaborative Research Cluster, Tokyo Institute of Technology, Yokohama, Japan,International Research Center for Neurointelligence, Institutes for Advanced Study, The University of Tokyo, Tokyo, Japan
| | - Fumi Kano
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan,Multimodal Cell Analysis Collaborative Research Cluster, Tokyo Institute of Technology, Yokohama, Japan,*Correspondence: Fumi Kano,
| |
Collapse
|
3
|
Lee S, Kim S, Jeon JS. Microfluidic outer blood-retinal barrier model for inducing wet age-related macular degeneration by hypoxic stress. LAB ON A CHIP 2022; 22:4359-4368. [PMID: 36254466 DOI: 10.1039/d2lc00672c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Wet age-related macular degeneration (AMD) is a severe ophthalmic disease that develops in the outer blood-retinal barrier (oBRB), involving two types of cells, the retinal pigment epithelium (RPE) and the choriocapillaris endothelium (CCE). Unfortunately, the pathogenesis of AMD is unclear, and the risk of the only effective therapy (Anti-VEGF injection) has been consistently argued. Also, since oBRB is hard to observe in vivo, an in vitro model for the pathological study is necessary. Here, we propose an advanced oBRB model, enhanced in two major ways: fully vascularized CCE and the in vivo analogous distance between RPE and CCE. Our model consists of an RPE (ARPE-19) monolayer with adjacent CCE (HUVEC) embedded fibrin gel in the microfluidic chip and required four days to construct an oBRB. Notably, the intercellular distance was tuned to the in vivo scale (<100 μm) without any extraneous scaffold in between. Thus, the two cell layers can interact freely through the extracellular matrix (ECM) in vivo. This is significant as wet AMD is mainly developed through broken intercellular interaction. Thanks to this in vivo similarity, the model incubated under hypoxic conditions, similar to an oxygen-induced retinopathy animal model, showed upregulated vascularization comparable to the AMD condition. We envisage that our model can be used to assist the investigation of AMD.
Collapse
Affiliation(s)
- Seokhun Lee
- Department of Mechanical Engineering, KAIST, Daejeon 34141, Korea.
| | - Seunggyu Kim
- Department of Mechanical Engineering, KAIST, Daejeon 34141, Korea.
| | - Jessie S Jeon
- Department of Mechanical Engineering, KAIST, Daejeon 34141, Korea.
| |
Collapse
|
4
|
A tango for coats and membranes: New insights into ER-to-Golgi traffic. Cell Rep 2022; 38:110258. [DOI: 10.1016/j.celrep.2021.110258] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 11/17/2021] [Accepted: 12/21/2021] [Indexed: 12/30/2022] Open
|
5
|
D'Agostino M, Scerra G, Cannata Serio M, Caporaso MG, Bonatti S, Renna M. Unconventional secretion of α-Crystallin B requires the Autophagic pathway and is controlled by phosphorylation of its serine 59 residue. Sci Rep 2019; 9:16892. [PMID: 31729431 PMCID: PMC6858465 DOI: 10.1038/s41598-019-53226-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 08/14/2019] [Indexed: 01/26/2023] Open
Abstract
α-Crystallin B (CRYAB or HspB5) is a chaperone member of the small heat-shock protein family that prevents aggregation of many cytosolic client proteins by means of its ATP-independent holdase activity. Surprisingly, several reports show that CRYAB exerts a protective role also extracellularly, and it has been recently demonstrated that CRYAB is secreted from human retinal pigment epithelial cells by an unconventional secretion pathway that involves multi-vesicular bodies. Here we show that autophagy is crucial for this unconventional secretion pathway and that phosphorylation at serine 59 residue regulates CRYAB secretion by inhibiting its recruitment to the autophagosomes. In addition, we found that autophagosomes containing CRYAB are not able to fuse with lysosomes. Therefore, CRYAB is capable to highjack and divert autophagosomes toward the exocytic pathway, inhibiting their canonical route leading to the lysosomal compartment. Potential implications of these findings in the context of disease-associated mutant proteins turn-over are discussed.
Collapse
Affiliation(s)
- M D'Agostino
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Naples, Italy.
| | - G Scerra
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Naples, Italy
| | - M Cannata Serio
- Laboratory of Epithelial Biology and Disease, Imagine Institute, Paris, France.,Université Paris Descartes-Sorbonne Paris Cité, Imagine Institute, Paris, France
| | - M G Caporaso
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Naples, Italy
| | - S Bonatti
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Naples, Italy
| | - M Renna
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Naples, Italy.
| |
Collapse
|
6
|
Murakami M, Kano F, Murata M. LLO-mediated Cell Resealing System for Analyzing Intracellular Activity of Membrane-impermeable Biopharmaceuticals of Mid-sized Molecular Weight. Sci Rep 2018; 8:1946. [PMID: 29386585 PMCID: PMC5792490 DOI: 10.1038/s41598-018-20482-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 01/19/2018] [Indexed: 12/23/2022] Open
Abstract
Cell-based assays have become increasingly important in the preclinical studies for biopharmaceutical products such as specialty peptides, which are of interest owing to their high substrate specificity. However, many of the latter are membrane impermeable and must be physically introduced into cells to evaluate their intracellular activities. We previously developed a "cell-resealing technique" that exploited the temperature-dependent pore-forming activity of the streptococcal toxin, streptolysin O (SLO), that enabled us to introduce various molecules into cells for evaluation of their intracellular activities. In this study, we report a new cell resealing method, the listeriolysin O (LLO)-mediated resealing method, to deliver mid-sized, membrane-impermeable biopharmaceuticals into cells. We found that LLO-type resealing required no exogenous cytosol to repair the injured cell membrane and allowed the specific entry of mid-sized molecules into cells. We use this method to introduce either a membrane-impermeable, small compound (8-OH-cAMP) or specialty peptide (Akt-in), and demonstrated PKA activation or Akt inhibition, respectively. Collectively, the LLO-type resealing method is a user-friendly and reproducible intracellular delivery system for mid-sized membrane-impermeable molecules into cells and for evaluating their intracellular activities.
Collapse
Affiliation(s)
- Masataka Murakami
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan
| | - Fumi Kano
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan.,Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan
| | - Masayuki Murata
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan. .,Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan. .,Laboratoty of Frontier Image Analysis, Graduate School of Arts and Science, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan.
| |
Collapse
|
7
|
Establishment and phenotyping of disease model cells created by cell-resealing technique. Sci Rep 2017; 7:15167. [PMID: 29123170 PMCID: PMC5680332 DOI: 10.1038/s41598-017-15443-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 10/23/2017] [Indexed: 12/28/2022] Open
Abstract
Cell-based assays are growing in importance for screening drugs and investigating their mechanisms of action. Most of the assays use so-called “normal” cell strain because it is difficult to produce cell lines in which the disease conditions are reproduced. In this study, we used a cell-resealing technique, which reversibly permeabilizes the plasma membrane, to develop diabetic (Db) model hepatocytes into which cytosol from diabetic mouse liver had been introduced. Db model hepatocytes showed several disease-specific phenotypes, namely disturbance of insulin-induced repression of gluconeogenic gene expression and glucose secretion. Quantitative image analysis and principal component analysis revealed that the ratio of phosphorylated Akt (pAkt) to Akt was the best index to describe the difference between wild-type and Db model hepatocytes. By performing image-based drug screening, we found pioglitazone, a PPARγ agonist, increased the pAkt/Akt ratio, which in turn ameliorated the insulin-induced transcriptional repression of the gluconeogenic gene phosphoenolpyruvate carboxykinase 1. The disease-specific model cells coupled with image-based quantitative analysis should be useful for drug development, enabling the reconstitution of disease conditions at the cellular level and the discovery of disease-specific markers.
Collapse
|
8
|
Du W, Su QP, Chen Y, Zhu Y, Jiang D, Rong Y, Zhang S, Zhang Y, Ren H, Zhang C, Wang X, Gao N, Wang Y, Sun L, Sun Y, Yu L. Kinesin 1 Drives Autolysosome Tubulation. Dev Cell 2017; 37:326-336. [PMID: 27219061 DOI: 10.1016/j.devcel.2016.04.014] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 01/14/2016] [Accepted: 04/20/2016] [Indexed: 12/11/2022]
Abstract
Autophagic lysosome reformation (ALR) plays an important role in maintaining lysosome homeostasis. During ALR, lysosomes are reformed by recycling lysosomal components from autolysosomes. The most noticeable step of ALR is autolysosome tubulation, but it is currently unknown how the process is regulated. Here, using an approach combining in vivo studies and in vitro reconstitution, we found that the kinesin motor protein KIF5B is required for autolysosome tubulation and that KIF5B drives autolysosome tubulation by pulling on the autolysosomal membrane. Furthermore, we show that KIF5B directly interacts with PtdIns(4,5)P2. Kinesin motors are recruited and clustered on autolysosomes via interaction with PtdIns(4,5)P2 in a clathrin-dependent manner. Finally, we demonstrate that clathrin promotes formation of PtdIns(4,5)P2-enriched microdomains, which are required for clustering of KIF5B. Our study reveals a mechanism by which autolysosome tubulation was generated.
Collapse
Affiliation(s)
- Wanqing Du
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China; School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Qian Peter Su
- State Key Laboratory of Membrane Biology, Biodynamic Optical Imaging Center (BIOPIC), School of Life Sciences, Peking University, Beijing 100871, China
| | - Yang Chen
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yueyao Zhu
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Dong Jiang
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yueguang Rong
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Senyan Zhang
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yixiao Zhang
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - He Ren
- School of Life Sciences, Peking University, Beijing 100871, China
| | - Chuanmao Zhang
- School of Life Sciences, Peking University, Beijing 100871, China
| | - Xinquan Wang
- School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Ning Gao
- School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yanfeng Wang
- School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Lingfei Sun
- School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yujie Sun
- State Key Laboratory of Membrane Biology, Biodynamic Optical Imaging Center (BIOPIC), School of Life Sciences, Peking University, Beijing 100871, China; School of Life Sciences, Peking University, Beijing 100871, China.
| | - Li Yu
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China.
| |
Collapse
|
9
|
Teng KW, Ishitsuka Y, Ren P, Youn Y, Deng X, Ge P, Lee SH, Belmont AS, Selvin PR. Labeling proteins inside living cells using external fluorophores for microscopy. eLife 2016; 5. [PMID: 27935478 PMCID: PMC5148600 DOI: 10.7554/elife.20378] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 11/21/2016] [Indexed: 12/31/2022] Open
Abstract
Site-specific fluorescent labeling of proteins inside live mammalian cells has been achieved by employing Streptolysin O, a bacterial toxin which forms temporary pores in the membrane and allows delivery of virtually any fluorescent probes, ranging from labeled IgG’s to small ligands, with high efficiency (>85% of cells). The whole process, including recovery, takes 30 min, and the cell is ready to be imaged immediately. A variety of cell viability tests were performed after treatment with SLO to ensure that the cells have intact membranes, are able to divide, respond normally to signaling molecules, and maintains healthy organelle morphology. When combined with Oxyrase, a cell-friendly photostabilizer, a ~20x improvement in fluorescence photostability is achieved. By adding in glutathione, fluorophores are made to blink, enabling super-resolution fluorescence with 20–30 nm resolution over a long time (~30 min) under continuous illumination. Example applications in conventional and super-resolution imaging of native and transfected cells include p65 signal transduction activation, single molecule tracking of kinesin, and specific labeling of a series of nuclear and cytoplasmic protein complexes. DOI:http://dx.doi.org/10.7554/eLife.20378.001
Collapse
Affiliation(s)
- Kai Wen Teng
- Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, United States.,Center for Physics of Living Cell, University of Illinois at Urbana-Champaign, Urbana, United States
| | - Yuji Ishitsuka
- Center for Physics of Living Cell, University of Illinois at Urbana-Champaign, Urbana, United States.,Department of Physics, University of Illinois at Urbana-Champaign, Urbana, United States
| | - Pin Ren
- Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, United States.,Center for Physics of Living Cell, University of Illinois at Urbana-Champaign, Urbana, United States
| | - Yeoan Youn
- Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, United States.,Center for Physics of Living Cell, University of Illinois at Urbana-Champaign, Urbana, United States
| | - Xiang Deng
- Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Urbana, United States
| | - Pinghua Ge
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana, United States
| | - Sang Hak Lee
- Center for Physics of Living Cell, University of Illinois at Urbana-Champaign, Urbana, United States.,Department of Physics, University of Illinois at Urbana-Champaign, Urbana, United States
| | - Andrew S Belmont
- Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, United States.,Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Urbana, United States
| | - Paul R Selvin
- Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, United States.,Center for Physics of Living Cell, University of Illinois at Urbana-Champaign, Urbana, United States.,Department of Physics, University of Illinois at Urbana-Champaign, Urbana, United States.,Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Urbana, United States
| |
Collapse
|
10
|
Matsuto M, Kano F, Murata M. Reconstitution of the targeting of Rab6A to the Golgi apparatus in semi-intact HeLa cells: A role of BICD2 in stabilizing Rab6A on Golgi membranes and a concerted role of Rab6A/BICD2 interactions in Golgi-to-ER retrograde transport. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:2592-609. [PMID: 25962623 DOI: 10.1016/j.bbamcr.2015.05.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2014] [Revised: 05/02/2015] [Accepted: 05/05/2015] [Indexed: 12/21/2022]
Abstract
Rab is a small GTP-binding protein family that regulates various pathways of vesicular transport. Although more than 60 Rab proteins are targeted to specific organelles in mammalian cells, the mechanisms underlying the specificity of Rab proteins for the respective organelles remain unknown. In this study, we reconstituted the Golgi targeting of Rab6A in streptolysin O (SLO)-permeabilized HeLa cells in a cytosol-dependent manner and investigated the biochemical requirements of targeting. Golgi-targeting assays identified Bicaudal-D (BICD)2, which is reportedly involved in the dynein-mediated transport of mRNAs during oogenesis and embryogenesis in Drosophila, as a cytosolic factor for the Golgi targeting of Rab6A in SLO-permeabilized HeLa cells. Subsequent immunofluorescence analyses indicated decreased amounts of the GTP-bound active form of Rab6 in BICD2-knockdown cells. In addition, fluorescence recovery after photobleaching (FRAP) analyses revealed that overexpression of the C-terminal region of BICD2 decreased the exchange rate of GFP-Rab6A between the Golgi membrane and the cytosol. Collectively, these results indicated that BICD2 facilitates the binding of Rab6A to the Golgi by stabilizing its GTP-bound form. Moreover, several analyses of vesicular transport demonstrated that Rab6A and BICD2 play crucial roles in Golgi tubule fusion with the endoplasmic reticulum (ER) in brefeldin A (BFA)-treated cells, indicating that BICD2 is involved in coat protein I (COPI)-independent Golgi-to-ER retrograde vesicular transport.
Collapse
Affiliation(s)
- Mariko Matsuto
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Komaba 3-8-1, Meguro-ku, Tokyo 153-8902, Japan
| | - Fumi Kano
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Komaba 3-8-1, Meguro-ku, Tokyo 153-8902, Japan; PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
| | - Masayuki Murata
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Komaba 3-8-1, Meguro-ku, Tokyo 153-8902, Japan.
| |
Collapse
|
11
|
Ikeda K, Fujioka K, Tachibana T, Kim SU, Tojo K, Manome Y. Secretion of urocortin I by human glioblastoma cell lines, possibly via the constitutive pathway. Peptides 2015; 63:63-70. [PMID: 25239507 DOI: 10.1016/j.peptides.2014.09.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2014] [Revised: 09/08/2014] [Accepted: 09/08/2014] [Indexed: 11/24/2022]
Abstract
Corticotropin-releasing factor (CRF) and its family of peptides, i.e., urocortins (UCNs), play a critical role in systemic and peripheral stress-response systems and are widely expressed not only in normal tissues but also in various types of cancer cells. Given limited understanding of the mechanism of UCN I secretion, we investigated the UCN I secretory pathway in human neural stem cells (HNSCs) and in two glioblastoma cell lines, e.g., A172 and U-138 MG. Immunoreactivities for CRF receptors were detected in A172 glioblastoma cells, but not in HNSCs or U-138 glioblastoma cells, while UCN I immunoreactivity was detected in A172 and U-138 MG glioblastoma cell lines by both light field and electron microscopy. Interestingly, electron microscopy revealed UCN I immunoreactivtiy in vesicle-like structures in the plasma membrane of the glioblastoma cells. Tracking of a hybrid fluorescent protein containing a UCN I signal peptide expressed in A172 human glioblastoma cells revealed that fluorescence in secretory granules could be decreased by cycloheximide (100μg/ml), indicating that the forward transport of secretory granules containing fluorescent protein was not altered by the inhibition of protein synthesis by cycloheximide. Retrograde transport and the fusion of fluorescent granules in A172 human glioblastoma cells was induced by brefeldin A (10μg/ml), indicating that UCN I secretory granules may be transported via the constitutive pathway. Based on these results, it appears that UCN I is secreted from human glioblastoma cells by exocytosis through constitutive secretory granules, indicating that transcription of UCN I mRNA may be correlated to secretion of UCN I protein.
Collapse
Affiliation(s)
- Keiichi Ikeda
- Division of Molecular Cell Biology, Core Research Facilities for Basic Science, Research Center for Medical Sciences, The Jikei University School of Medicine, Tokyo 105-8461, Japan.
| | - Kouki Fujioka
- Division of Molecular Cell Biology, Core Research Facilities for Basic Science, Research Center for Medical Sciences, The Jikei University School of Medicine, Tokyo 105-8461, Japan
| | - Toshiaki Tachibana
- Division of Molecular Cell Biology, Core Research Facilities for Basic Science, Research Center for Medical Sciences, The Jikei University School of Medicine, Tokyo 105-8461, Japan
| | - Seung U Kim
- Medical Research Institute, Chung-Ang University College of Medicine, Seoul, Republic of Korea; Division of Neurology, Department of Medicine, University of British Columbia, Vancouver, BC, Canada V6T 2B5
| | - Katsuyoshi Tojo
- Division of Diabetes and Endocrinology, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo 105-8461, Japan
| | - Yoshinobu Manome
- Division of Molecular Cell Biology, Core Research Facilities for Basic Science, Research Center for Medical Sciences, The Jikei University School of Medicine, Tokyo 105-8461, Japan
| |
Collapse
|
12
|
Kano F, Nakatsu D, Noguchi Y, Yamamoto A, Murata M. A resealed-cell system for analyzing pathogenic intracellular events: perturbation of endocytic pathways under diabetic conditions. PLoS One 2012; 7:e44127. [PMID: 22952896 PMCID: PMC3430665 DOI: 10.1371/journal.pone.0044127] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Accepted: 07/30/2012] [Indexed: 12/25/2022] Open
Abstract
Cell-based assay systems that can serve as cellular models of aberrant function in pathogenic organs would be novel and useful tools for screening drugs and clarifying the molecular mechanisms of various diseases. We constructed model cells that replicated the conditions in diabetic hepatocytes by using the cell resealing technique, which enables the exchange of cytosol. The plasma membrane of HeLa cells was permeabilized with the streptococcal toxin streptolysin O, and cytosol that had been prepared from wild-type or db/db diabetic mice was introduced into the resulting semi-intact cells. By resealing the plasma membrane by exposure to Ca2+, we created WT or Db model cells, in which the cytosolic conditions replicated those of healthy or diabetic liver. Interestingly, phosphorylation of p38 MAPK was promoted, whereas the level of endosomal phosphatidylinositol-3-phosphate was decreased, in Db cells. We investigated several endocytic pathways in WT and Db cells, and found that retrograde endosome-to-Golgi transport was delayed in a p38 MAPK-dependent manner in Db cells. Furthermore, the degradation pathway of the EGF receptor from endosomes to lysosomes was enhanced in Db cells, and this did not depend on the activation of p38 MAPK. The disease model cell system should become a powerful tool for the detection of aberrant processes in cells under pathogenic conditions and for therapeutic applications.
Collapse
Affiliation(s)
- Fumi Kano
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Meguro-ku, Tokyo, Japan
- PRESTO, Japan Science and Technology Agency, Saitama, Japan
| | - Daiki Nakatsu
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Meguro-ku, Tokyo, Japan
| | - Yoshiyuki Noguchi
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Meguro-ku, Tokyo, Japan
| | - Akitsugu Yamamoto
- Department of Cell Biology, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, Japan
| | - Masayuki Murata
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Meguro-ku, Tokyo, Japan
- * E-mail:
| |
Collapse
|
13
|
Lisauskas T, Matula P, Claas C, Reusing S, Wiemann S, Erfle H, Lehmann L, Fischer P, Eils R, Rohr K, Storrie B, Starkuviene V. Live-cell assays to identify regulators of ER-to-Golgi trafficking. Traffic 2012; 13:416-32. [PMID: 22132776 DOI: 10.1111/j.1600-0854.2011.01318.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2011] [Revised: 11/28/2011] [Accepted: 12/01/2011] [Indexed: 11/27/2022]
Abstract
We applied fluorescence microscopy-based quantitative assays to living cells to identify regulators of endoplasmic reticulum (ER)-to-Golgi trafficking and/or Golgi complex maintenance. We first validated an automated procedure to identify factors which influence Golgi-to-ER relocalization of GalT-CFP (β1,4-galactosyltransferase I-cyan fluorescent protein) after brefeldin A (BFA) addition and/or wash-out. We then tested 14 proteins that localize to the ER and/or Golgi complex when overexpressed for a role in ER-to-Golgi trafficking. Nine of them interfered with the rate of BFA-induced redistribution of GalT-CFP from the Golgi complex to the ER, six of them interfered with GalT-CFP redistribution from the ER to a juxtanuclear region (i.e. the Golgi complex) after BFA wash-out and six of them were positive effectors in both assays. Notably, our live-cell approach captures regulator function in ER-to-Golgi trafficking, which was missed in previous fixed cell assays, as well as assigns putative roles for other less characterized proteins. Moreover, we show that our assays can be extended to RNAi and chemical screens.
Collapse
|
14
|
NISHIO TAKASHI, NIIKURA KENICHI, MATSUO YASUTAKA, IJIRO KUNIHARU. ENHANCED ACCUMULATION OF CARBOHYDRATE-DISPLAYING CdTe QUANTUM DOTS IN CELLS RESPONDING TO CELLULAR CHEMICAL STRESSES. INTERNATIONAL JOURNAL OF NANOSCIENCE 2011. [DOI: 10.1142/s0219581x09005694] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We propose a novel stress sensing methods using water soluble, sugar-displaying quantum dot and digitonin-permeabilized semi-intact HeLa cells. The amount of GlcNAc -QDs (N-acetylglucosamine-displaying quantum dots) binding to heavy metal ion exposed cells was investigated by fluorescence intensity, and it increased in a dose-dependent manner. This result suggests that GlcNAc -QD could be applied for a new stress sensing probe.
Collapse
Affiliation(s)
- TAKASHI NISHIO
- Department of Chemistry, Graduate School of Science, Hokkaido University, N21W10, Sapporo 001-0021, Japan
| | - KENICHI NIIKURA
- Research Institute for Electronic Science, Hokkaido University, N21W10, Sapporo 001-0021, Japan
| | - YASUTAKA MATSUO
- Research Institute for Electronic Science, Hokkaido University, N21W10, Sapporo 001-0021, Japan
| | - KUNIHARU IJIRO
- Research Institute for Electronic Science, Hokkaido University, N21W10, Sapporo 001-0021, Japan
| |
Collapse
|
15
|
Fujikawa M, Yoshida M. A sensitive, simple assay of mitochondrial ATP synthesis of cultured mammalian cells suitable for high-throughput analysis. Biochem Biophys Res Commun 2010; 401:538-43. [PMID: 20875793 DOI: 10.1016/j.bbrc.2010.09.089] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2010] [Accepted: 09/22/2010] [Indexed: 10/19/2022]
Abstract
A new assay has been developed to measure mitochondrial ATP synthesis of cultured mammalian cells. Cells in a microplate are exposed to streptolysin O to make plasma membranes permeable without damaging mitochondrial function and ATP synthesis is monitored by luciferase. Addition of inhibitors of F₀F₁-ATP synthase (F₀F₁), respiratory chain, TCA cycle and ATP/ADP translocator, as well as knockdown of β-subunit of F₀F₁, resulted in loss of ATP synthesis. Compared with the conventional procedures that need mitochondria fractionation and detergent, this assay is simple, sensitive and suitable for high-throughput analysis of genes and drugs that could affect mitochondrial functional integrity as represented by ATP synthesis activity.
Collapse
Affiliation(s)
- Makoto Fujikawa
- ICORP ATP-Synthesis Regulation Project, Japan Science and Technology Agency (JST), Aomi 2-3-6, Tokyo 135-0064, Japan
| | | |
Collapse
|
16
|
Morikawa RK, Aoki J, Kano F, Murata M, Yamamoto A, Tsujimoto M, Arai H. Intracellular phospholipase A1gamma (iPLA1gamma) is a novel factor involved in coat protein complex I- and Rab6-independent retrograde transport between the endoplasmic reticulum and the Golgi complex. J Biol Chem 2009; 284:26620-30. [PMID: 19632984 DOI: 10.1074/jbc.m109.038869] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The mammalian intracellular phospholipase A(1) (iPLA(1)) family consists of three members, iPLA(1)alpha/PA-PLA(1), iPLA(1)beta/p125, and iPLA(1)gamma/KIAA0725p. Although iPLA(1)beta has been implicated in organization of the ER-Golgi compartments, little is known about the physiological role of its closest paralog, iPLA(1)gamma. Here we show that iPLA(1)gamma mediates a specific retrograde membrane transport pathway between the endoplasmic reticulum (ER) and the Golgi complex. iPLA(1)gamma appeared to be localized to the cytosol, the cis-Golgi, and the ER-Golgi intermediate compartment (ERGIC). Time-lapse microscopy revealed that a population of GFP-iPLA(1)gamma was associated with transport carriers moving out from the Golgi complex. Knockdown of iPLA(1)gamma expression by RNAi did not affect the anterograde transport of VSVGts045 but dramatically delayed two types of Golgi-to-ER retrograde membrane transport; that is, transfer of the Golgi membrane into the ER in the presence of brefeldin A and delivery of cholera toxin B subunit from the Golgi complex to the ER. Notably, knockdown of iPLA(1)gamma did not impair COPI- and Rab6-dependent retrograde transports represented by ERGIC-53 recycling and ER delivery of Shiga toxin, respectively. Thus, iPLA(1)gamma is a novel membrane transport factor that contributes to a specific Golgi-to-ER retrograde pathway distinct from presently characterized COPI- and Rab6-dependent pathways.
Collapse
Affiliation(s)
- Rei K Morikawa
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | | | | | | | | | | | | |
Collapse
|
17
|
Pohl A, López-Montero I, Pohl A, López-Montero I, Rouvière F, Giusti F, Devaux PF. Rapid transmembrane diffusion of ceramide and dihydroceramide spin-labelled analogues in the liquid ordered phase. Mol Membr Biol 2009; 26:194-204. [DOI: 10.1080/09687680902733815] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
18
|
Kano F, Yamauchi S, Yoshida Y, Watanabe-Takahashi M, Nishikawa K, Nakamura N, Murata M. Yip1A regulates the COPI-independent retrograde transport from the Golgi complex to the ER. J Cell Sci 2009; 122:2218-27. [PMID: 19509059 DOI: 10.1242/jcs.043414] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Yip1A, a mammalian homologue of yeast Yip1p, is a multi-spanning membrane protein that is considered to be involved in transport between the endoplasmic reticulum (ER) and the Golgi. However, the precise role of Yip1A in mammalian cells remains unclear. We show here that endogenous Yip1A is localized to the ER-Golgi intermediate compartment (ERGIC). Knockdown of Yip1A by RNAi did not induce morphological changes in the Golgi, ER, or ERGIC. By analyzing a number of intracellular transport pathways, we found that Yip1A knockdown delayed the transport of Shiga toxin from the Golgi to the ER, but did not affect the anterograde transport of VSVGts045. We also found that a recombinant protein that corresponded to the N-terminal domain of Yip1A inhibited the COPI-independent retrograde transport of GFP-tagged galactosyltransferase, GT-GFP, but not the COPI-dependent retrograde transport of p58/ERGIC53. Furthermore, we found that Yip1A knockdown resulted in the dissociation of Rab6 from the membranes. These results suggested that Yip1A has a role in COPI-independent retrograde transport from the Golgi to the ER and regulates the membrane recruitment of Rab6.
Collapse
Affiliation(s)
- Fumi Kano
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Komaba 3-8-1, Meguro-ku, Tokyo 153-8902, Japan
| | | | | | | | | | | | | |
Collapse
|
19
|
Abstract
Pseudomonas aeruginosa ExoS is a bifunctional type III cytotoxin that disrupts Ras- and Rho-signaling pathways in mammalian cells. A hydrophobic region (residues 51-77, termed the membrane localization domain) targets ExoS to the plasma membrane (PM) and late endosomes of host cells. In the current study, metabolic inhibitors and dominant-negative proteins that disrupt known vesicle-trafficking pathways were used to define the intracellular trafficking of ExoS. Release of ExoS from PM was independent of dynamin and ADP ribosylation factor 6 but inhibited by methyl-beta-cyclodextrin, a cholesterol-depleting reagent, and perinuclear localization of ExoS was disrupted by nocodazole. p50 dynamitin, a dynein inhibitor partially disrupted perinuclear localization of ExoS. Methyl-beta-cyclodextrin and nocodazole inhibited the ability of type-III-delivered ExoS to ADP-ribosylated Golgi/endoplasmic reticulum-resident Ras. Methyl-beta-cyclodextrin also relocated ExoS from the perinuclear region to the PM, indicating that ExoS can cycle through anterograde as well as through retrograde trafficking pathways. These findings show that ExoS endocytosis is cholesterol dependent, and it utilizes host microtubules, for intracellular trafficking. Understanding how type III cytotoxins enter and traffic within mammalian cells may identify new targets for therapeutic intervention of gram-negative bacterial pathogens.
Collapse
Affiliation(s)
- Qing Deng
- Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | | | | |
Collapse
|
20
|
Kano F, Kondo H, Yamamoto A, Kaneko Y, Uchiyama K, Hosokawa N, Nagata K, Murata M. NSF/SNAPs and p97/p47/VCIP135 are sequentially required for cell cycle-dependent reformation of the ER network. Genes Cells 2006; 10:989-99. [PMID: 16164599 DOI: 10.1111/j.1365-2443.2005.00894.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The endoplasmic reticulum (ER) has a characteristic polygonal structure with hallmark three-way junctions. In a previous paper, we reconstituted the disruption of the pre-existing ER network using mitotic cytosol from HeLa cells in streptolysin O (SLO)-permeabilized CHO-HSP cells (stably expressing GFP-HSP47). In addition, we found that interphase cytosol induced reformation of the disrupted ER network into a continuous network structure. Here, we show that the reformation of the ER network is accomplished through two sequential fusion reactions. The first process is mediated by NSF/alpha and gamma-SNAPs, and involves the generation of typical membranous intermediate structures that connect the disrupted ER tubules. A subsequent fusion is mediated by p97/p47/VCIP135, which has been shown to be required for homotypic fusion events in Golgi cisternae regrowth after mitosis. In addition, we also found that both fusion processes involve the t-SNARE, syntaxin 18.
Collapse
Affiliation(s)
- Fumi Kano
- Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Tokyo 153-8902, Japan
| | | | | | | | | | | | | | | |
Collapse
|
21
|
Kano F, Takenaka K, Murata M. Reconstitution of Golgi disassembly by mitotic Xenopus egg extract in semi-intact MDCK cells. Methods Mol Biol 2006; 322:357-65. [PMID: 16739736 DOI: 10.1007/978-1-59745-000-3_25] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Semi-intact cells are cells with plasma membranes that have been permeabilized by bacterial pore-forming toxins or surfactants. The addition of mitotic Xenopus egg extract to semi-intact cells can reconstitute a number of intracellular events that occur specifically at the onset of mitosis. In this chapter, we describe methods for reconstituting the disassembly of the Golgi apparatus by introducing mitotic Xenopus egg extract into semi-intact Mardin-Darby canine kidney (MDCK) cells. The Golgi apparatus was visualized in the cells by expression of green fluorescence protein (GFP)-tagged galactosyltransferase, a marker of trans-Golgi cisternae. Xenopus egg extracts arrested at mitosis or interphase were then prepared and added to the semi-intact MDCK cells. Disassembly of the Golgi apparatus was induced by mitotic Xenopus egg extract. This system can be used not only to elucidate the factors that are involved in the reconstitution process, but also to dissect the process into several elementary steps morphologically and biochemically.
Collapse
Affiliation(s)
- Fumi Kano
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Japan
| | | | | |
Collapse
|
22
|
Barzilay E, Ben-Califa N, Hirschberg K, Neumann D. Uncoupling of brefeldin a-mediated coatomer protein complex-I dissociation from Golgi redistribution. Traffic 2005; 6:794-802. [PMID: 16101682 DOI: 10.1111/j.1600-0854.2005.00317.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The Golgi complex functions in transport of molecules from the endoplasmic reticulum (ER) to the plasma membrane and other distal organelles as well as in retrograde transport to the ER. The fungal metabolite brefeldin A (BFA) promotes dissociation of ADP-ribosylation-factor-1 (ARF1) and the coatomer protein complex-I (COP-I) from Golgi membranes, followed by Golgi tubulation and fusion with the ER. Here we demonstrate that the cationic ionophore monensin inhibited the BFA-mediated Golgi redistribution to the ER without interfering with ARF1 and COP-I dissociation. Preservation of a perinuclear Golgi despite COP-I and ARF1 dissociation enables addressing the involvement of these proteins in anterograde ER to Golgi transport. The thermo-reversible folding mutant of vesicular stomatitis virus G protein (VSVGtsO45) was retained in the ER in the presence of both monensin and BFA, thus supporting ARF1/COP-I participation in ER-exit processes. Live-cell imaging revealed that BFA-induced Golgi tubulation persisted longer in the presence of monensin, suggesting that monensin inhibits tubule fusion with the ER. Moreover, monensin also augmented Golgi-derived tubules that contained the ER-Golgi-intermediate compartment marker, p58, in the absence of BFA, signifying the generality of this effect. Taken together, we propose that monensin inhibits membrane fusion processes in the presence or absence of BFA.
Collapse
Affiliation(s)
- Eran Barzilay
- Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel-Aviv University, Ramat-Aviv 69978, Israel
| | | | | | | |
Collapse
|
23
|
Kano F, Kondo H, Yamamoto A, Tanaka AR, Hosokawa N, Nagata K, Murata M. The maintenance of the endoplasmic reticulum network is regulated by p47, a cofactor of p97, through phosphorylation by cdc2 kinase. Genes Cells 2005; 10:333-44. [PMID: 15773896 DOI: 10.1111/j.1365-2443.2005.00837.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The endoplasmic reticulum (ER) has a characteristic complex polygonal structure with hallmark three-way junctions in many types of cells. To investigate the mechanisms responsible for maintaining the ER network, we established ER disassembly and reassembly assays in semi-intact Chinese hamster ovary (CHO) cells that constitutively expressed heat shock protein-47 fused to the green fluorescent protein (GFP-HSP47) as an ER marker (the cells are referred to as CHO-HSP cells). Using these assays, we found that maintenance of the ER network required cytosol and adenosine triphosphate/guanosine 5'-triphosphate (ATP/GTP) hydrolysis, but not actin filaments or microtubules. We also showed that the ER network was disrupted upon addition of either N-ethylmaleimide-treated cytosol after washing semi-intact cells with high salt solution or mitotic cytosol in nocodazole-treated semi-intact CHO-HSP cells. The disrupted ER network induced by mitotic cytosol was reformed by the addition of interphase cytosol. In addition, we found that p47, a cofactor of p97, was essential for the maintenance of the ER network, and that phosphorylation of p47 by cdc2 kinase resulted in ER network disruption by mitotic cytosol. Taken together, these results imply that the maintenance of the ER network requires a membrane fusion process mediated by p97/p47, and that cell cycle-dependent morphological changes of the ER network are regulated through phosphorylation/dephosphorylation of p47.
Collapse
Affiliation(s)
- Fumi Kano
- Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Tokyo 153-8902, Japan
| | | | | | | | | | | | | |
Collapse
|
24
|
Ichinose J, Murata M, Yanagida T, Sako Y. EGF signalling amplification induced by dynamic clustering of EGFR. Biochem Biophys Res Commun 2004; 324:1143-9. [PMID: 15485674 DOI: 10.1016/j.bbrc.2004.09.173] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2004] [Indexed: 01/09/2023]
Abstract
Lateral interaction is an important feature of various types of cell surface receptors including the receptor tyrosine kinases (RTKs). Here we report that dynamic lateral interaction produces amplification and variation in signalling of the EGF receptor, a member of RTKs. Binding of EGF is known to induce transphosphorylation inside EGFR dimers. Using single-molecule techniques, the relationship between EGF binding and EGFR phosphorylation has been determined. The number of phosphorylated EGFR molecules became larger than that of EGF binding as unliganded EGFR was phosphorylated, meaning an amplification of EGF signalling. EGFR formed clusters continuously exchanging their elements through thermal diffusion, and direct and/or indirect lateral interactions. As a result, various types of activation sites differing in number of activated receptors were generated. Amplification required no cytoplasmic factors and was observed on semi-intact cells for a wide range of number of EGFR molecules (10(4)-10(6) per cell) suggesting generality of this process.
Collapse
Affiliation(s)
- Junya Ichinose
- Nanobiology Laboratories, Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan
| | | | | | | |
Collapse
|
25
|
Kano F, Tanaka AR, Yamauchi S, Kondo H, Murata M. Cdc2 kinase-dependent disassembly of endoplasmic reticulum (ER) exit sites inhibits ER-to-Golgi vesicular transport during mitosis. Mol Biol Cell 2004; 15:4289-98. [PMID: 15254263 PMCID: PMC515359 DOI: 10.1091/mbc.e03-11-0822] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
We observed the disassembly of endoplasmic reticulum (ER) exit sites (ERES) by confocal microscopy during mitosis in Chinese hamster ovary (CHO) cells by using Yip1A fused to green fluorescence protein (GFP) as a transmembrane marker of ERES. Photobleaching experiments revealed that Yip1A-GFP, which was restricted to the ERES during interphase, diffused throughout the ER network during mitosis. Next, we reconstituted mitotic disassembly of Yip1A-GFP-labeled ERES in streptolysin O-permeabilized CHO cells by using mitotic L5178Y cytosol. Using the ERES disassembly assay and the anterograde transport assay of GFP-tagged VSVGts045, we demonstrated that the phosphorylation of p47 by Cdc2 kinase regulates the disassembly of ERES and results in the specific inhibition of ER-to-Golgi transport during mitosis.
Collapse
Affiliation(s)
- Fumi Kano
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
| | | | | | | | | |
Collapse
|
26
|
Chan D, Strang M, Judson B, Brown WJ. Inhibition of membrane tubule formation and trafficking by isotetrandrine, an antagonist of G-protein-regulated phospholipase A2 enzymes. Mol Biol Cell 2004; 15:1871-80. [PMID: 14767064 PMCID: PMC379283 DOI: 10.1091/mbc.e03-09-0644] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2003] [Revised: 11/30/2003] [Accepted: 01/11/2004] [Indexed: 11/11/2022] Open
Abstract
Previous studies have established a role for cytoplasmic phospholipase A(2) (PLA(2)) activity in tubule-mediated retrograde trafficking between the Golgi complex and the endoplasmic reticulum (ER). However, little else is known about how membrane tubule formation is regulated. This study demonstrates that isotetrandrine (ITD), a biscoclaurine alkaloid known to inhibit PLA(2) enzyme activation by heterotrimeric G-proteins, effectively prevented brefeldin A (BFA)-induced tubule formation from the Golgi complex and retrograde trafficking to the ER. In addition, ITD inhibited BFA-stimulated tubule formation from the trans-Golgi network and endosomes. ITD inhibition of the BFA response was potent (IC(50) approximately 10-20 microM) and rapid (complete inhibition with a 10-15-min preincubation). ITD also inhibited normal retrograde trafficking as revealed by the formation of nocodazole-induced Golgi mini-stacks at ER exit sites. Treatment of cells with ITD alone caused the normally interconnected Golgi ribbons to become fragmented and dilated, but cisternae were still stacked and located in a juxtanuclear position. These results suggest that a G-protein-binding PLA(2) enzyme plays a pivotal role in tubule mediated trafficking between the Golgi and the ER, the maintenance of the interconnected ribbons of Golgi stacks, and tubule formation from endosomes.
Collapse
Affiliation(s)
- Diane Chan
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 18483, USA
| | | | | | | |
Collapse
|
27
|
Drecktrah D, Chambers K, Racoosin EL, Cluett EB, Gucwa A, Jackson B, Brown WJ. Inhibition of a Golgi complex lysophospholipid acyltransferase induces membrane tubule formation and retrograde trafficking. Mol Biol Cell 2003; 14:3459-69. [PMID: 12925777 PMCID: PMC181581 DOI: 10.1091/mbc.e02-11-0711] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Recent studies have suggested that formation of Golgi membrane tubules involves the generation of membrane-associated lysophospholipids by a cytoplasmic Ca2+-independent phospholipase A2 (PLA2). Herein, we provide additional support for this idea by showing that inhibition of lysophospholipid reacylation by a novel Golgi-associated lysophosphatidylcholine acyltransferase (LPAT) induces the rapid tubulation of Golgi membranes, leading in their retrograde movement to the endoplasmic reticulum. Inhibition of the Golgi LPAT was achieved by 2,2-dimethyl-N-(2,4,6-trimethoxyphenyl)dodecanamide (CI-976), a previously characterized antagonist of acyl-CoA cholesterol acyltransferase. The effect of CI-976 was similar to that of brefeldin A, except that the coatomer subunit beta-COP remained on Golgi-derived membrane tubules. CI-976 also enhanced the cytosol-dependent formation of tubules from Golgi complexes in vitro and increased the levels of lysophosphatidylcholine in Golgi membranes. Moreover, preincubation of cells with PLA2 antagonists inhibited the ability of CI-976 to induce tubules. These results suggest that Golgi membrane tubule formation can result from increasing the content of lysophospholipids in membranes, either by stimulation of a PLA2 or by inhibition of an LPAT. These two opposing enzyme activities may help to coordinately regulate Golgi membrane shape and tubule formation.
Collapse
Affiliation(s)
- Daniel Drecktrah
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853, USA
| | | | | | | | | | | | | |
Collapse
|
28
|
Kikuchi S, Shinpo K, Tsuji S, Yabe I, Niino M, Tashiro K. Brefeldin A-induced neurotoxicity in cultured spinal cord neurons. J Neurosci Res 2003; 71:591-9. [PMID: 12548716 DOI: 10.1002/jnr.10479] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Brefeldin A (BFA) is a fungus metabolite that is known to cause the disassembly of the Golgi complex and apoptosis in exposed cells, both of which have been suggested as playing roles in the pathogenesis of neurodegenerative diseases, particularly amyotrophic lateral sclerosis (ALS). This study showed that BFA caused neurotoxicity and apoptotic nuclear changes in cultured spinal neurons of rat spinal cord in a dose- and time-dependent manner. The spinal motor neurons were more vulnerable to this neurotoxicity. The cultured spinal neurons showed irreversible disassembly of the Golgi apparatus as early as 1 hr after exposure to BFA. BFA induced the expression and activation of caspase-12 beginning 8 hr after exposure. The level of the cleaved form of caspase-3 had increased 12 hr after the addition of BFA. Free radical generation and loss of mitochondrial membrane potential were observed in the later stages of neurotoxicity caused by BFA. Collectively, our data suggests that BFA is an excellent agent for reproducing the pathophysiological features of ALS. This in vitro model may be useful in attempts to study the mechanisms of this neurodegenerative disease and to examine therapeutic potentials.
Collapse
Affiliation(s)
- Seiji Kikuchi
- Department of Neurology, Hokkaido University School of Medicine, Sapporo, Hokkaido, Japan.
| | | | | | | | | | | |
Collapse
|
29
|
Sako Y, Ichinose J, Morimatsu M, Ohta K, Uyemura T. Optical Bioimaging: From Living Tissue to a Single Molecule: Single-Molecule Visualization of Cell Signaling Processes of Epidermal Growth Factor Receptor. J Pharmacol Sci 2003; 93:253-8. [PMID: 14646241 DOI: 10.1254/jphs.93.253] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Single-molecule imaging is an ideal technology to study molecular mechanisms of biological reactions in vitro. Recently, this technology has been extended to real-time observation of fluorescent dye-labeled molecules in living cells. Total internal reflection fluorescence microscopy is the major technique for this purpose. Using this technique, we have studied the process of early signal transduction of epidermal growth factor (EGF) in single molecules: binding of EGF to its receptor (EGFR) on the cell surface, dimerization of EGFR induced by binding of EGF, fluctuation of the structure of EGFR clusters, activation of EGFR through tyrosine phosphorylations on its cytoplasmic domain, and recognition of activated EGFR by a cytoplasmic adaptor protein, Grb2. EGF induces intracellular calcium response, sometimes caused by less than one hundred EGF molecules. Single-molecule studies suggested that this highly sensitive response to EGF was due to the amplification of the EGFR signal using dynamic clustering, reorganization of the dimers, and lateral mobility of EGFR on the cell surface. Through these studies, single-molecule analysis has proven to be a powerful technology to analyze intracellular protein systems.
Collapse
Affiliation(s)
- Yasushi Sako
- Nanobiology Laboratories, Graduate School of Frontier Biosciences, Osaka University, Suita, Japan.
| | | | | | | | | |
Collapse
|
30
|
Sako Y, Uyemura T. Total internal reflection fluorescence microscopy for single-molecule imaging in living cells. Cell Struct Funct 2002; 27:357-65. [PMID: 12502890 DOI: 10.1247/csf.27.357] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Marvelous background rejection in total internal reflection fluorescence microscopy (TIR-FM) has made it possible to visualize single-fluorophores in living cells. Cell signaling proteins including peptide hormones, membrane receptors, small G proteins, cytoplasmic kinases as well as small signaling compounds have been conjugated with single chemical fluorophore or tagged with green fluorescent proteins and visualized in living cells. In this review, the reasons why single-molecule analysis is essential for studies of intracellular protein systems such as cell signaling system are discussed, the instrumentation of TIR-FM for single-molecule imaging in living cells is explained, and how single molecule visualization has been used in cell biology is illustrated by way of two examples: signaling of epidermal growth factor in mammalian cells and chemotaxis of Dictyostelium amoeba along a cAMP gradient. Single-molecule analysis is an ideal method to quantify the parameters of reaction dynamics and kinetics of unitary processes within intracellular protein systems. Knowledge of these parameters is crucial for the understanding of the molecular mechanisms underlying intracellular events, thus single-molecule imaging in living cells will be one of the major technologies in cellular nanobiology.
Collapse
Affiliation(s)
- Yasushi Sako
- Department of Physiology and Biosignaling, Graduate School of Medicine, Osaka University.
| | | |
Collapse
|
31
|
Daull P, Home W, Boileau G, LeBel D. Brefeldin A-induced prosomatostatin N-glycosylation in AtT20 cells. Biochem Biophys Res Commun 2002; 296:618-24. [PMID: 12176026 DOI: 10.1016/s0006-291x(02)00904-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Prosomatostatin, the precursor of the hormone somatostatin, harbors an N-glycosylation site in its prodomain that has never been shown to be modified by the N-oligosaccharyl transferase (OST) of the endoplasmic reticulum (ER). The addition of Brefeldin A (BFA) to prosomatostatin transfected AtT20 cells leads to a quantitative glycosylation of the prohormone. Upon removal of the BFA the glycosylated hormone precursor is not deglycosylated, and is secreted after maturation of its oligosaccharide chain in the late secretory pathway. In addition, a significant proportion of the glycosylated hormone precursor remains in the cell. Since BFA is known to induce an effective collapse of the Golgi complex into the ER, the hypothesis that a prolonged exposure to the ER glycosylation machinery is responsible for the glycosylation was tested. No N-glycosylation was detected using a coupled in vitro transcription-translation system in the presence of canine pancreatic microsomes, indicating that rapid transit through the ER does not explain the lack of glycosylation observed in vivo in the absence of BFA. These observations show that co-translational glycosylation by OST becomes possible due to a still unidentified modification in the luminal environment brought about by the coalescence of the Golgi into the ER caused by BFA.
Collapse
Affiliation(s)
- Philippe Daull
- Department of Biology, Université de Sherbrooke, Sherbrooke, Quebec, Canada J1K 2R1
| | | | | | | |
Collapse
|
32
|
Kawamoto K, Yoshida Y, Tamaki H, Torii S, Shinotsuka C, Yamashina S, Nakayama K. GBF1, a guanine nucleotide exchange factor for ADP-ribosylation factors, is localized to the cis-Golgi and involved in membrane association of the COPI coat. Traffic 2002; 3:483-95. [PMID: 12047556 DOI: 10.1034/j.1600-0854.2002.30705.x] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Formation of coated carrier vesicles, such as COPI-coated vesicles from the cis-Golgi, is triggered by membrane binding of the GTP-bound form of ADP-ribosylation factors. This process is blocked by brefeldin A, which is an inhibitor of guanine nucleotide exchange factors for ADP-ribosylation factor. GBF1 is one of the guanine nucleotide-exchange factors for ADP-ribosylation factor and is localized in the Golgi region. In the present study, we have determined the detailed subcellular localization of GBF1. Immunofluorescence microscopy of cells treated with nocodazole or incubated at 15 degrees C has suggested that GBF1 behaves similarly to proteins recycling between the cis-Golgi and the endoplasmic reticulum. Immunoelectron microscopy has revealed that GBF1 localizes primarily to vesicular and tubular structures apposed to the cis-face of Golgi stacks and minor fractions to the Golgi stacks. GBF1 overexpressed in cells causes recruitment of class I and class II ADP-ribosylation factors onto Golgi membranes. Furthermore, overexpressed GBF1 antagonizes various effects of brefeldin A, such as inhibition of membrane recruitment of ADP-ribosylation factors and the COPI coat, and redistribution of Golgi-resident and itinerant proteins. These observations indicate that GBF1 is involved in the formation of COPI-coated vesicles from the cis-Golgi or the pre-Golgi intermediate compartment through activating ADP-ribosylation factors.
Collapse
Affiliation(s)
- Kazumasa Kawamoto
- Institute of Biological Sciences and Gene Research Center, University of Tsukuba, Tsukuba Science City, Ibaraki 305-8572, Japan
| | | | | | | | | | | | | |
Collapse
|