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Zhang Y, Lin C. Lipid osmosis, membrane tension, and other mechanochemical driving forces of lipid flow. Curr Opin Cell Biol 2024; 88:102377. [PMID: 38823338 PMCID: PMC11193448 DOI: 10.1016/j.ceb.2024.102377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 05/12/2024] [Accepted: 05/13/2024] [Indexed: 06/03/2024]
Abstract
Nonvesicular lipid transport among different membranes or membrane domains plays crucial roles in lipid homeostasis and organelle biogenesis. However, the forces that drive such lipid transport are not well understood. We propose that lipids tend to flow towards the membrane area with a higher membrane protein density in a process termed lipid osmosis. This process lowers the membrane tension in the area, resulting in a membrane tension difference called osmotic membrane tension. We examine the thermodynamic basis and experimental evidence of lipid osmosis and osmotic membrane tension. We predict that lipid osmosis can drive bulk lipid flows between different membrane regions through lipid transfer proteins, scramblases, or similar barriers that selectively pass lipids but not membrane proteins. We also speculate on the biological functions of lipid osmosis. Finally, we explore other driving forces for lipid transfer and describe potential methods and systems to further test our theory.
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Affiliation(s)
- Yongli Zhang
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA.
| | - Chenxiang Lin
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA; Nanobiology Institute, Yale University, West Haven, CT 06516, USA; Department of Biomedical Engineering, Yale University, New Haven, CT 06520, USA.
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2
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Zhang Y, Lin C. Lipid osmosis, membrane tension, and other mechanochemical driving forces of lipid flow. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.08.574656. [PMID: 38260424 PMCID: PMC10802412 DOI: 10.1101/2024.01.08.574656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Nonvesicular lipid transport among different membranes or membrane domains plays crucial roles in lipid homeostasis and organelle biogenesis. However, the forces that drive such lipid transport are not well understood. We propose that lipids tend to flow towards the membrane area with a higher membrane protein density in a process termed lipid osmosis. This process lowers the membrane tension in the area, resulting in a membrane tension difference called osmotic membrane tension. We examine the thermodynamic basis and experimental evidence of lipid osmosis and osmotic membrane tension. We predict that lipid osmosis can drive bulk lipid flows between different membrane regions through lipid transfer proteins, scramblases, or other similar barriers that selectively pass lipids but not membrane proteins. We also speculate on the biological functions of lipid osmosis. Finally, we explore other driving forces for lipid transfer and describe potential methods and systems to further test our theory.
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Affiliation(s)
- Yongli Zhang
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
| | - Chenxiang Lin
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA
- Nanobiology Institute, Yale University, West Haven, CT 06516, USA
- Department of Biomedical Engineering, Yale University, New Haven, CT 06520, USA
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3
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Liu X, Li Y, Gu M, Xu T, Wang C, Chang P. Radiation enteropathy-related depression: A neglectable course of disease by gut bacterial dysbiosis. Cancer Med 2024; 13:e6865. [PMID: 38457257 PMCID: PMC10923036 DOI: 10.1002/cam4.6865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 12/08/2023] [Accepted: 12/12/2023] [Indexed: 03/10/2024] Open
Abstract
Radiation enteropathy (RE) is common in patients treated with radiotherapy for pelvic-abdominal cancers. Accumulating data indicate that gut commensal bacteria determine intestinal radiosensitivity. Radiotherapy can result in gut bacterial dysbiosis. Gut bacterial dysbiosis contributes to the pathogenesis of RE. Mild to moderate depressive symptoms can be observed in patients with RE in clinical settings; however, the rate of these symptoms has not been reported. Studies have demonstrated that gut bacterial dysbiosis induces depression. In the state of comorbidity, RE and depression may be understood as local and abscopal manifestations of gut bacterial disorders. The ability of comorbid depression to worsen inflammatory bowel disease (IBD) has long been demonstrated and is associated with dysfunction of cholinergic neural anti-inflammatory pathways. There is a lack of direct evidence for RE comorbid with depression. It is widely accepted that RE shares similar pathophysiologic mechanisms with IBD. Therefore, we may be able to draw on the findings of the relationship between IBD and depression. This review will explore the relationship between gut bacteria, RE, and depression in light of the available evidence and indicate a method for investigating the mechanisms of RE combined with depression. We will also describe new developments in the treatment of RE with probiotics, prebiotics, and fecal microbial transplantation.
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Affiliation(s)
- Xinliang Liu
- Department of Radiation Oncology and TherapyThe First Hospital of Jilin UniversityChangchunChina
| | - Ying Li
- Department of Radiation Oncology and TherapyThe First Hospital of Jilin UniversityChangchunChina
| | - Meichen Gu
- Department of Radiation Oncology and TherapyThe First Hospital of Jilin UniversityChangchunChina
| | - Tiankai Xu
- Department of Radiation Oncology and TherapyThe First Hospital of Jilin UniversityChangchunChina
| | - Chuanlei Wang
- Department of Hepatobiliary and Pancreatic Surgery, General Surgery CenterThe First Hospital of Jilin UniversityChangchunChina
| | - Pengyu Chang
- Department of Radiation Oncology and TherapyThe First Hospital of Jilin UniversityChangchunChina
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4
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Zheng S, Zheng B, Fu C. The Roles of Septins in Regulating Fission Yeast Cytokinesis. J Fungi (Basel) 2024; 10:115. [PMID: 38392788 PMCID: PMC10890454 DOI: 10.3390/jof10020115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 01/26/2024] [Accepted: 01/28/2024] [Indexed: 02/24/2024] Open
Abstract
Cytokinesis is required to separate two daughter cells at the end of mitosis, and septins play crucial roles in many aspects of cytokinesis. While septins have been intensively studied in many model organisms, including the budding yeast Saccharomyces cerevisiae, septins have been relatively less characterized in the fission yeast Schizosaccharomyces pombe, which has proven to be an excellent model organism for studying fundamental cell biology. In this review, we summarize the findings of septins made in fission yeasts mainly from four aspects: the domain structure of septins, the localization of septins during the cell cycle, the roles of septins in regulating cytokinesis, and the regulatory proteins of septins.
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Affiliation(s)
- Shengnan Zheng
- MOE Key Laboratory for Cellular Dynamics & Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230027, China
- Anhui Key Laboratory of Cellular Dynamics and Chemical Biology & Hefei National Research Center for Interdisciplinary Sciences at the Microscale, School of Life Sciences, University of Science and Technology of China, Hefei 230027, China
| | - Biyu Zheng
- MOE Key Laboratory for Cellular Dynamics & Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230027, China
- Anhui Key Laboratory of Cellular Dynamics and Chemical Biology & Hefei National Research Center for Interdisciplinary Sciences at the Microscale, School of Life Sciences, University of Science and Technology of China, Hefei 230027, China
| | - Chuanhai Fu
- MOE Key Laboratory for Cellular Dynamics & Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230027, China
- Anhui Key Laboratory of Cellular Dynamics and Chemical Biology & Hefei National Research Center for Interdisciplinary Sciences at the Microscale, School of Life Sciences, University of Science and Technology of China, Hefei 230027, China
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5
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Geiser A, Foylan S, Tinning PW, Bryant NJ, Gould GW. GLUT4 dispersal at the plasma membrane of adipocytes: a super-resolved journey. Biosci Rep 2023; 43:BSR20230946. [PMID: 37791639 PMCID: PMC10600063 DOI: 10.1042/bsr20230946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 10/03/2023] [Accepted: 10/04/2023] [Indexed: 10/05/2023] Open
Abstract
In adipose tissue, insulin stimulates glucose uptake by mediating the translocation of GLUT4 from intracellular vesicles to the plasma membrane. In 2010, insulin was revealed to also have a fundamental impact on the spatial distribution of GLUT4 within the plasma membrane, with the existence of two GLUT4 populations at the plasma membrane being defined: (1) as stationary clusters and (2) as diffusible monomers. In this model, in the absence of insulin, plasma membrane-fused GLUT4 are found to behave as clusters. These clusters are thought to arise from exocytic events that retain GLUT4 at their fusion sites; this has been proposed to function as an intermediate hub between GLUT4 exocytosis and re-internalisation. By contrast, insulin stimulation induces the dispersal of GLUT4 clusters into monomers and favours a distinct type of GLUT4-vesicle fusion event, known as fusion-with-release exocytosis. Here, we review how super-resolution microscopy approaches have allowed investigation of the characteristics of plasma membrane-fused GLUT4 and further discuss regulatory step(s) involved in the GLUT4 dispersal machinery, introducing the scaffold protein EFR3 which facilitates localisation of phosphatidylinositol 4-kinase type IIIα (PI4KIIIα) to the cell surface. We consider how dispersal may be linked to the control of transporter activity, consider whether macro-organisation may be a widely used phenomenon to control proteins within the plasma membrane, and speculate on the origin of different forms of GLUT4-vesicle exocytosis.
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Affiliation(s)
- Angéline Geiser
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, U.K
| | - Shannan Foylan
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, U.K
| | - Peter W Tinning
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, U.K
| | - Nia J Bryant
- Department of Biology, University of York, Heslington, York, U.K
| | - Gwyn W Gould
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, U.K
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Wang X, Chen C, Yan J, Xu Y, Pan D, Wang L, Yang M. Druggability of Targets for Diagnostic Radiopharmaceuticals. ACS Pharmacol Transl Sci 2023; 6:1107-1119. [PMID: 37588760 PMCID: PMC10425999 DOI: 10.1021/acsptsci.3c00081] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Indexed: 08/18/2023]
Abstract
Targets play an indispensable and pivotal role in the development of radiopharmaceuticals. However, the initial stages of drug discovery projects are often plagued by frequent failures due to inadequate information on druggability and suboptimal target selection. In this context, we aim to present a comprehensive review of the factors that influence target druggability for diagnostic radiopharmaceuticals. Specifically, we explore the crucial determinants of target specificity, abundance, localization, and positivity rate and their respective implications. Through a detailed analysis of existing protein targets, we elucidate the significance of each factor. By carefully considering and balancing these factors during the selection of targets, more efficacious and targeted radiopharmaceuticals are expected to be designed for the diagnosis of a wide range of diseases in the future.
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Affiliation(s)
- Xinyu Wang
- NHC
Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular
Nuclear Medicine, Jiangsu Institute of Nuclear
Medicine, Wuxi 214063, PR China
- School
of Pharmacy, Nanjing Medical University, Nanjing 211166, PR China
| | - Chongyang Chen
- NHC
Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular
Nuclear Medicine, Jiangsu Institute of Nuclear
Medicine, Wuxi 214063, PR China
| | - Junjie Yan
- NHC
Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular
Nuclear Medicine, Jiangsu Institute of Nuclear
Medicine, Wuxi 214063, PR China
- School
of Pharmacy, Nanjing Medical University, Nanjing 211166, PR China
| | - Yuping Xu
- NHC
Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular
Nuclear Medicine, Jiangsu Institute of Nuclear
Medicine, Wuxi 214063, PR China
- School
of Pharmacy, Nanjing Medical University, Nanjing 211166, PR China
| | - Donghui Pan
- NHC
Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular
Nuclear Medicine, Jiangsu Institute of Nuclear
Medicine, Wuxi 214063, PR China
| | - Lizhen Wang
- NHC
Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular
Nuclear Medicine, Jiangsu Institute of Nuclear
Medicine, Wuxi 214063, PR China
| | - Min Yang
- NHC
Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular
Nuclear Medicine, Jiangsu Institute of Nuclear
Medicine, Wuxi 214063, PR China
- School
of Pharmacy, Nanjing Medical University, Nanjing 211166, PR China
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7
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Thallmair V, Schultz L, Evers S, Jolie T, Goecke C, Leitner MG, Thallmair S, Oliver D. Localization of the tubby domain, a PI(4,5)P2 biosensor, to E-Syt3-rich endoplasmic reticulum-plasma membrane junctions. J Cell Sci 2023; 136:jcs260848. [PMID: 37401342 PMCID: PMC10445746 DOI: 10.1242/jcs.260848] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 06/26/2023] [Indexed: 07/05/2023] Open
Abstract
The phospholipid phosphatidylinositol (4,5)-bisphosphate [PI(4,5)P2] acts as a signaling lipid at the plasma membrane (PM) with pleiotropic regulatory actions on multiple cellular processes. Signaling specificity might result from spatiotemporal compartmentalization of the lipid and from combinatorial binding of PI(4,5)P2 effector proteins to additional membrane components. Here, we analyzed the spatial distribution of tubbyCT, a paradigmatic PI(4,5)P2-binding domain, in live mammalian cells by total internal reflection fluorescence (TIRF) microscopy and molecular dynamics simulations. We found that unlike other well-characterized PI(4,5)P2 recognition domains, tubbyCT segregates into distinct domains within the PM. TubbyCT enrichment occurred at contact sites between PM and endoplasmic reticulum (ER) (i.e. at ER-PM junctions) as shown by colocalization with ER-PM markers. Localization to these sites was mediated in a combinatorial manner by binding to PI(4,5)P2 and by interaction with a cytosolic domain of extended synaptotagmin 3 (E-Syt3), but not other E-Syt isoforms. Selective localization to these structures suggests that tubbyCT is a novel selective reporter for a ER-PM junctional pool of PI(4,5)P2. Finally, we found that association with ER-PM junctions is a conserved feature of tubby-like proteins (TULPs), suggesting an as-yet-unknown function of TULPs.
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Affiliation(s)
- Veronika Thallmair
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
- DFG Research Training Group, Membrane Plasticity in Tissue Development and Remodeling, GRK 2213, Philipps UniversityMarburg, 35037 Marburg, Germany
| | - Lea Schultz
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
| | - Saskia Evers
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
| | - Theresa Jolie
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
| | - Christian Goecke
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
| | - Michael G. Leitner
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
- Institute of Physiology, Department of Physiology and Medical Physics, Medical University of Innsbruck, 6020 Innsbruck, Austria
- Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH&Co.KG, Birkendorfer Str. 65, 88400 Biberach an der Riß, Germany
| | - Sebastian Thallmair
- Frankfurt Institute for Advanced Studies, 60438 Frankfurt am Main, Germany
- Groningen Biomolecular Sciences and Biotechnology Institute and The Zernike Institute for Advanced Material, University of Groningen, 9747 AG Groningen, The Netherlands
| | - Dominik Oliver
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
- DFG Research Training Group, Membrane Plasticity in Tissue Development and Remodeling, GRK 2213, Philipps UniversityMarburg, 35037 Marburg, Germany
- Center for Mind, Brain and Behavior (CMBB), Universities of Marburg and Giessen, 35032 Marburg, Germany
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8
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Rochussen AM, Lippert AH, Griffiths GM. Imaging the T-cell receptor: new approaches, new insights. Curr Opin Immunol 2023; 82:102309. [PMID: 37011462 DOI: 10.1016/j.coi.2023.102309] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 03/02/2023] [Accepted: 03/03/2023] [Indexed: 04/03/2023]
Abstract
T cells recognize pathogenic antigens via the T-cell antigen receptor (TCR). This protein complex binds to antigen fragments on the surface of antigen-presenting cells. To understand how cellular activation can ensue rapidly from molecular recognition, the localization and distribution of the TCR on the surface of the resting T cell are of particular importance. Conflicting results regarding TCR distribution have emerged from recent studies using a range of imaging techniques, including total internal reflection and single-molecule localization microscopy modalities. Here, we review the differing results and the potential biases inherent in differing imaging approaches. In addition, we review studies showing the impact of differing imaging surfaces on T-cell activation.
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Tantiwong C, Dunster JL, Cavill R, Tomlinson MG, Wierling C, Heemskerk JWM, Gibbins JM. An agent-based approach for modelling and simulation of glycoprotein VI receptor diffusion, localisation and dimerisation in platelet lipid rafts. Sci Rep 2023; 13:3906. [PMID: 36890261 PMCID: PMC9994409 DOI: 10.1038/s41598-023-30884-6] [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: 08/25/2022] [Accepted: 03/02/2023] [Indexed: 03/10/2023] Open
Abstract
Receptor diffusion plays an essential role in cellular signalling via the plasma membrane microenvironment and receptor interactions, but the regulation is not well understood. To aid in understanding of the key determinants of receptor diffusion and signalling, we developed agent-based models (ABMs) to explore the extent of dimerisation of the platelet- and megakaryocyte-specific receptor for collagen glycoprotein VI (GPVI). This approach assessed the importance of glycolipid enriched raft-like domains within the plasma membrane that lower receptor diffusivity. Our model simulations demonstrated that GPVI dimers preferentially concentrate in confined domains and, if diffusivity within domains is decreased relative to outside of domains, dimerisation rates are increased. While an increased amount of confined domains resulted in further dimerisation, merging of domains, which may occur upon membrane rearrangements, was without effect. Modelling of the proportion of the cell membrane which constitutes lipid rafts indicated that dimerisation levels could not be explained by these alone. Crowding of receptors by other membrane proteins was also an important determinant of GPVI dimerisation. Together, these results demonstrate the value of ABM approaches in exploring the interactions on a cell surface, guiding the experimentation for new therapeutic avenues.
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Affiliation(s)
- Chukiat Tantiwong
- School of Biological Sciences, University of Reading, Reading, UK.,Department of Biochemistry, CARIM, Maastricht University, Maastricht, The Netherlands
| | - Joanne L Dunster
- School of Biological Sciences, University of Reading, Reading, UK
| | - Rachel Cavill
- Department of Data Science and Knowledge Engineering, Maastricht University, Maastricht, The Netherlands
| | | | | | - Johan W M Heemskerk
- Department of Biochemistry, CARIM, Maastricht University, Maastricht, The Netherlands.,Synapse Research Institute, Maastricht, The Netherlands
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Priyanka U, Lens PNL. Enhanced production of amylase, pyruvate and phenolic compounds from glucose by light-driven Aspergillus niger-CuS nanobiohybrids. JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY (OXFORD, OXFORDSHIRE : 1986) 2023; 98:602-614. [PMID: 37066082 PMCID: PMC10087041 DOI: 10.1002/jctb.7153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 05/29/2022] [Accepted: 06/08/2022] [Indexed: 06/19/2023]
Abstract
BACKGROUND The demand for value-added compounds such as amylase, pyruvate and phenolic compounds produced by biological methods has prompted the rapid development of advanced technologies for their enhanced production. Nanobiohybrids (NBs) make use of both the microbial properties of whole-cell microorganisms and the light-harvesting efficiency of semiconductors. Photosynthetic NBs were constructed that link the biosynthetic pathways of Aspergillus niger with CuS nanoparticles. RESULTS In this work, NB formation was confirmed by negative values of the interaction energy, i.e., 2.31 × 108 to -5.52 × 108 kJ mol-1 for CuS-Che NBs, whereas for CuS-Bio NBs the values were -2.31 × 108 to -4.62 × 108 kJ mol-1 for CuS-Bio NBs with spherical nanoparticle interaction. For CuS-Bio NBs with nanorod interaction, it ranged from -2.3 × 107 to -3.47 × 107 kJ mol-1 . Further, the morphological changes observed by scanning electron microscopy showed the presence of the elements Cu and S in the energy-dispersive X-ray spectra and the presence of CuS bonds in Fourier transform infrared spectroscopy indicate NB formation. In addition, the quenching effect in photoluminescence studies confirmed NB formation. Production yields of amylase, phenolic compounds and pyruvate amounted to 11.2 μmol L-1, 52.5 μmol L-1 and 28 nmol μL-1, respectively, in A. niger-CuS Bio NBs on the third day of incubation in the bioreactor. Moreover, A niger cells-CuS Bio NBs had amino acids and lipid yields of 6.2 mg mL-1 and 26.5 mg L-1, respectively. Furthermore, probable mechanisms for the enhanced production of amylase, pyruvate and phenolic compounds are proposed. CONCLUSION Aspergillus niger-CuS NBs were used for the production of the amylase enzyme and value-added compounds such as pyruvate and phenolic compounds. Aspergillus niger-CuS Bio NBs showed a greater efficiency compared to A. niger-CuS Che NBs as the biologically produced CuS nanoparticles had a higher compatibility with A. niger cells. © 2022 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI).
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Affiliation(s)
- Uddandarao Priyanka
- Department of Microbiology and Ryan InstituteNational University of IrelandGalwayIreland
| | - Piet NL Lens
- Department of Microbiology and Ryan InstituteNational University of IrelandGalwayIreland
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11
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Cabral-Dias R, Antonescu CN. Control of phosphatidylinositol-3-kinase signaling by nanoscale membrane compartmentalization. Bioessays 2023; 45:e2200196. [PMID: 36567275 DOI: 10.1002/bies.202200196] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 09/12/2022] [Accepted: 12/13/2022] [Indexed: 12/27/2022]
Abstract
Phosphatidylinositol-3-kinases (PI3Ks) are lipid kinases that produce 3-phosphorylated derivatives of phosphatidylinositol upon activation by various cues. These 3-phosphorylated lipids bind to various protein effectors to control many cellular functions. Lipid phosphatases such as phosphatase and tensin homolog (PTEN) terminate PI3K-derived signals and are critical to ensure appropriate signaling outcomes. Many lines of evidence indicate that PI3Ks and PTEN, as well as some specific lipid effectors are highly compartmentalized, either in plasma membrane nanodomains or in endosomal compartments. We examine the evidence for specific recruitment of PI3Ks, PTEN, and other related enzymes to membrane nanodomains and endocytic compartments. We then examine the hypothesis that scaffolding of the sources (PI3Ks), terminators (PTEN), and effectors of these lipid signals with a common plasma membrane nanodomain may achieve highly localized lipid signaling and ensure selective activation of specific effectors. This highlights the importance of spatial regulation of PI3K signaling in various physiological and disease contexts.
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Affiliation(s)
- Rebecca Cabral-Dias
- Department of Chemistry and Biology and Graduate Program in Molecular Science, Toronto Metropolitan University, Toronto, Ontario, Canada
| | - Costin N Antonescu
- Department of Chemistry and Biology and Graduate Program in Molecular Science, Toronto Metropolitan University, Toronto, Ontario, Canada
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12
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Rajapaksha SP, Nawagamuwage SU. Anticorrelated position fluctuation of lipids in forming membrane water pores: molecular dynamics simulations study with dengue virus capsid protein. J Biomol Struct Dyn 2022; 40:11395-11404. [PMID: 34343444 DOI: 10.1080/07391102.2021.1958698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The traffic of molecules into or out of cells is regulated by many membrane-associated mechanisms. Membrane pores are considered as one of the major passage mechanisms, although molecular-level understanding of pore formation is still vague. The opening of a membrane pore depends on many factors, including the influence of some proteins. The ability of the cell-penetrating peptides and supercharged proteins to form membrane pores has been reported. We studied pore formation through dipalmitoylphosphatidylcholine (DPPC) lipid bilayers by supercharged dengue virus capsid (C) protein. Atomistic molecular dynamics simulations confirmed the formation of membrane pores by a combined effect of the C protein and the membrane electric field. Analyses of simulated trajectories showed highly correlated vertical position fluctuations between the Cα atom of the membrane-anchored arginine residues and the phosphorus atoms of the surrounding DPPC lipids. Certain regions of the bilayer were negatively correlated while the others were positively correlated with respect to the fluctuations of the Cα atom of the anchored arginine residues. When positively correlated lipids in one leaflet vertically aligned with the negatively correlated lipids in the other leaflet, a local anticorrelated region was generated by weakening the bilayer. The membrane pore was always formed close to this anticorrelated region. Once formed, the C protein followed the hydrated pathway provided by the water-filled pores to cross the membrane.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Suneth P Rajapaksha
- Department of Chemistry, Faculty of Applied Sciences, University of Sri Jayewardenepura, Nugegoda, Sri Lanka
| | - Sithara U Nawagamuwage
- Department of Chemistry, Faculty of Applied Sciences, University of Sri Jayewardenepura, Nugegoda, Sri Lanka
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13
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Park K, Leroux MR. Composition, organization and mechanisms of the transition zone, a gate for the cilium. EMBO Rep 2022; 23:e55420. [PMID: 36408840 PMCID: PMC9724682 DOI: 10.15252/embr.202255420] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 08/08/2022] [Accepted: 10/31/2022] [Indexed: 11/22/2022] Open
Abstract
The cilium evolved to provide the ancestral eukaryote with the ability to move and sense its environment. Acquiring these functions required the compartmentalization of a dynein-based motility apparatus and signaling proteins within a discrete subcellular organelle contiguous with the cytosol. Here, we explore the potential molecular mechanisms for how the proximal-most region of the cilium, termed transition zone (TZ), acts as a diffusion barrier for both membrane and soluble proteins and helps to ensure ciliary autonomy and homeostasis. These include a unique complement and spatial organization of proteins that span from the microtubule-based axoneme to the ciliary membrane; a protein picket fence; a specialized lipid microdomain; differential membrane curvature and thickness; and lastly, a size-selective molecular sieve. In addition, the TZ must be permissive for, and functionally integrates with, ciliary trafficking systems (including intraflagellar transport) that cross the barrier and make the ciliary compartment dynamic. The quest to understand the TZ continues and promises to not only illuminate essential aspects of human cell signaling, physiology, and development, but also to unravel how TZ dysfunction contributes to ciliopathies that affect multiple organ systems, including eyes, kidney, and brain.
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Affiliation(s)
- Kwangjin Park
- Department of Molecular Biology and BiochemistrySimon Fraser UniversityBurnabyBCCanada
- Centre for Cell Biology, Development, and DiseaseSimon Fraser UniversityBurnabyBCCanada
- Present address:
Terry Fox LaboratoryBC CancerVancouverBCCanada
- Present address:
Department of Medical GeneticsUniversity of British ColumbiaVancouverBCCanada
| | - Michel R Leroux
- Department of Molecular Biology and BiochemistrySimon Fraser UniversityBurnabyBCCanada
- Centre for Cell Biology, Development, and DiseaseSimon Fraser UniversityBurnabyBCCanada
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14
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GLUT4 translocation and dispersal operate in multiple cell types and are negatively correlated with cell size in adipocytes. Sci Rep 2022; 12:20535. [PMID: 36446811 PMCID: PMC9708847 DOI: 10.1038/s41598-022-24736-y] [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: 08/08/2022] [Accepted: 11/18/2022] [Indexed: 11/30/2022] Open
Abstract
The regulated translocation of the glucose transporter, GLUT4, to the surface of adipocytes and muscle is a key action of insulin. This is underpinned by the delivery and fusion of GLUT4-containing vesicles with the plasma membrane. Recent studies have revealed that a further action of insulin is to mediate the dispersal of GLUT4 molecules away from the site of GLUT4 vesicle fusion with the plasma membrane. Although shown in adipocytes, whether insulin-stimulated dispersal occurs in other cells and/or is exhibited by other proteins remains a matter of debate. Here we show that insulin stimulates GLUT4 dispersal in the plasma membrane of adipocytes, induced pluripotent stem cell-derived cardiomyocytes and HeLa cells, suggesting that this phenomenon is specific to GLUT4 expressed in all cell types. By contrast, insulin-stimulated dispersal of TfR was not observed in HeLa cells, suggesting that the mechanism may be unique to GLUT4. Consistent with dispersal being an important physiological mechanism, we observed that insulin-stimulated GLUT4 dispersal is reduced under conditions of insulin resistance. Adipocytes of different sizes have been shown to exhibit distinct metabolic properties: larger adipocytes exhibit reduced insulin-stimulated glucose transport compared to smaller cells. Here we show that both GLUT4 delivery to the plasma membrane and GLUT4 dispersal are reduced in larger adipocytes, supporting the hypothesis that larger adipocytes are refractory to insulin challenge compared to their smaller counterparts, even within a supposedly homogeneous population of cells.
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15
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Strength in numbers: effect of protein crowding on the shape of cell membranes. Biochem Soc Trans 2022; 50:1257-1267. [PMID: 36214373 DOI: 10.1042/bst20210883] [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: 07/05/2022] [Revised: 09/16/2022] [Accepted: 09/20/2022] [Indexed: 11/17/2022]
Abstract
Continuous reshaping of the plasma membrane into pleomorphic shapes is critical for a plethora of cellular functions. How the cell carries out this enigmatic control of membrane remodeling has remained an active research field for decades and several molecular and biophysical mechanisms have shown to be involved in overcoming the energy barrier associated with membrane bending. The reported mechanisms behind membrane bending have been largely concerned with structural protein features, however, in the last decade, reports on the ability of densely packed proteins to bend membranes by protein-protein crowding, have challenged prevailing mechanistic views. Crowding has now been shown to generate spontaneous vesicle formation and tubular morphologies on cell- and model membranes, demonstrating crowding as a relevant player involved in the bending of membranes. Still, current research is largely based on unnatural overexpression of proteins in non-native domains, and together with efforts in modeling, this has led to questioning the in vivo impact of crowding. In this review, we examine this previously overlooked mechanism by summarizing recent advances in the understanding of protein-protein crowding and its prevalence in cellular membrane-shaping processes.
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16
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Gonçalves Antunes M, Sanial M, Contremoulins V, Carvalho S, Plessis A, Becam I. High hedgehog signaling is transduced by a multikinase-dependent switch controlling the apico-basal distribution of the GPCR smoothened. eLife 2022; 11:79843. [PMID: 36083801 PMCID: PMC9462849 DOI: 10.7554/elife.79843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 08/22/2022] [Indexed: 11/13/2022] Open
Abstract
The oncogenic G-protein-coupled receptor (GPCR) Smoothened (SMO) is a key transducer of the hedgehog (HH) morphogen, which plays an essential role in the patterning of epithelial structures. Here, we examine how HH controls SMO subcellular localization and activity in a polarized epithelium using the Drosophila wing imaginal disc as a model. We provide evidence that HH promotes the stabilization of SMO by switching its fate after endocytosis toward recycling. This effect involves the sequential and additive action of protein kinase A, casein kinase I, and the Fused (FU) kinase. Moreover, in the presence of very high levels of HH, the second effect of FU leads to the local enrichment of SMO in the most basal domain of the cell membrane. Together, these results link the morphogenetic effects of HH to the apico-basal distribution of SMO and provide a novel mechanism for the regulation of a GPCR.
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Affiliation(s)
| | | | | | | | - Anne Plessis
- Université Paris Cité, CNRS, Institut Jacques Monod
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17
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Waheed S, Li Z, Zhang F, Chiarini A, Armato U, Wu J. Engineering nano-drug biointerface to overcome biological barriers toward precision drug delivery. J Nanobiotechnology 2022; 20:395. [PMID: 36045386 PMCID: PMC9428887 DOI: 10.1186/s12951-022-01605-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 08/14/2022] [Indexed: 11/24/2022] Open
Abstract
The rapid advancement of nanomedicine and nanoparticle (NP) materials presents novel solutions potentially capable of revolutionizing health care by improving efficacy, bioavailability, drug targeting, and safety. NPs are intriguing when considering medical applications because of their essential and unique qualities, including a significantly higher surface to mass ratio, quantum properties, and the potential to adsorb and transport drugs and other compounds. However, NPs must overcome or navigate several biological barriers of the human body to successfully deliver drugs at precise locations. Engineering the drug carrier biointerface can help overcome the main biological barriers and optimize the drug delivery in a more personalized manner. This review discusses the significant heterogeneous biological delivery barriers and how biointerface engineering can promote drug carriers to prevail over hurdles and navigate in a more personalized manner, thus ushering in the era of Precision Medicine. We also summarize the nanomedicines' current advantages and disadvantages in drug administration, from natural/synthetic sources to clinical applications. Additionally, we explore the innovative NP designs used in both non-personalized and customized applications as well as how they can attain a precise therapeutic strategy.
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Affiliation(s)
- Saquib Waheed
- Department of Burn and Plastic Surgery, Shenzhen Institute of Translational Medicine, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, Shenzhen, 518035, China
- Department of Biomedical Engineering, School of Medicine, Shenzhen University, Shenzhen, 518060, China
| | - Zhibin Li
- Department of Burn and Plastic Surgery, Shenzhen Institute of Translational Medicine, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, Shenzhen, 518035, China
| | - Fangyingnan Zhang
- Department of Burn and Plastic Surgery, Shenzhen Institute of Translational Medicine, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, Shenzhen, 518035, China
| | - Anna Chiarini
- Human Histology & Embryology Section, Department of Surgery, Dentistry, Paediatrics & Gynaecology, University of Verona Medical School, 37134, Verona, Venetia, Italy
| | - Ubaldo Armato
- Department of Burn and Plastic Surgery, Shenzhen Institute of Translational Medicine, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, Shenzhen, 518035, China
- Human Histology & Embryology Section, Department of Surgery, Dentistry, Paediatrics & Gynaecology, University of Verona Medical School, 37134, Verona, Venetia, Italy
| | - Jun Wu
- Department of Burn and Plastic Surgery, Shenzhen Institute of Translational Medicine, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, Shenzhen, 518035, China.
- Human Histology & Embryology Section, Department of Surgery, Dentistry, Paediatrics & Gynaecology, University of Verona Medical School, 37134, Verona, Venetia, Italy.
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18
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Chai YJ, Cheng CY, Liao YH, Lin CH, Hsieh CL. Heterogeneous nanoscopic lipid diffusion in the live cell membrane and its dependency on cholesterol. Biophys J 2022; 121:3146-3161. [PMID: 35841144 PMCID: PMC9463655 DOI: 10.1016/j.bpj.2022.07.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 03/08/2022] [Accepted: 07/06/2022] [Indexed: 11/02/2022] Open
Abstract
Cholesterol plays a unique role in the regulation of membrane organization and dynamics by modulating the membrane phase transition at the nanoscale. Unfortunately, due to their small sizes and dynamic nature, the effects of cholesterol-mediated membrane nanodomains on membrane dynamics remain elusive. Here, using ultrahigh-speed single-molecule tracking with advanced optical microscope techniques, we investigate the diffusive motion of single phospholipids in the live cell plasma membrane at the nanoscale and its dependency on the cholesterol concentration. We find that both saturated and unsaturated phospholipids undergo anomalous subdiffusion on the length scale of 10-100 nm. The diffusion characteristics exhibit considerable variations in space and in time, indicating that the nanoscopic lipid diffusion is highly heterogeneous. Importantly, through the statistical analysis, apparent dual-mobility subdiffusion is observed from the mixed diffusion behaviors. The measured subdiffusion agrees well with the hop diffusion model that represents a diffuser moving in a compartmentalized membrane created by the cytoskeleton meshwork. Cholesterol depletion diminishes the lipid mobility with an apparently smaller compartment size and a stronger confinement strength. Similar results are measured with temperature reduction, suggesting that the more heterogeneous and restricted diffusion is connected to the nanoscopic membrane phase transition. Our conclusion supports the model that cholesterol depletion induces the formation of gel-phase, solid-like membrane nanodomains. These nanodomains undergo restricted diffusion and act as diffusion obstacles to the membrane molecules that are excluded from the nanodomains. This work provides the experimental evidence that the nanoscopic lipid diffusion in the cell plasma membrane is heterogeneous and sensitive to the cholesterol concentration and temperature, shedding new light on the regulation mechanisms of nanoscopic membrane dynamics.
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Affiliation(s)
- Yu-Jo Chai
- Institute of Atomic and Molecular Sciences (IAMS), Academia Sinica, Taipei, Taiwan
| | - Ching-Ya Cheng
- Institute of Atomic and Molecular Sciences (IAMS), Academia Sinica, Taipei, Taiwan
| | - Yi-Hung Liao
- Institute of Atomic and Molecular Sciences (IAMS), Academia Sinica, Taipei, Taiwan
| | - Chih-Hsiang Lin
- Institute of Atomic and Molecular Sciences (IAMS), Academia Sinica, Taipei, Taiwan
| | - Chia-Lung Hsieh
- Institute of Atomic and Molecular Sciences (IAMS), Academia Sinica, Taipei, Taiwan.
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19
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Donohoe C, Schaberle FA, Rodrigues FMS, Gonçalves NPF, Kingsbury CJ, Pereira MM, Senge MO, Gomes-da-Silva LC, Arnaut LG. Unraveling the Pivotal Role of Atropisomerism for Cellular Internalization. J Am Chem Soc 2022; 144:15252-15265. [PMID: 35960892 PMCID: PMC9446767 DOI: 10.1021/jacs.2c05844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The intrinsic challenge of large molecules to cross the cell membrane and reach intracellular targets is a major obstacle for the development of new medicines. We report how rotation along a single C-C bond, between atropisomers of a drug in clinical trials, improves cell uptake and therapeutic efficacy. The atropisomers of redaporfin (a fluorinated sulfonamide bacteriochlorin photosensitizer of 1135 Da) are separable and display orders of magnitude differences in photodynamic efficacy that are directly related to their differential cellular uptake. We show that redaporfin atropisomer uptake is passive and only marginally affected by ATP depletion, plasma proteins, or formulation in micelles. The α4 atropisomer, where meso-phenyl sulfonamide substituents are on the same side of the tetrapyrrole macrocycle, exhibits the highest cellular uptake and phototoxicity. This is the most amphipathic atropisomer with a conformation that optimizes hydrogen bonding (H-bonding) with polar head groups of membrane phospholipids. Consequently, α4 binds to the phospholipids on the surface of the membrane, flips into the membrane to adopt the orientation of a surfactant, and eventually diffuses to the interior of the cell (bind-flip mechanism). We observed increased α4 internalization by cells of the tumor microenvironment in vivo and correlated this to the response of photodynamic therapy when tumor illumination was performed 24 h after α4 administration. These results show that properly orientated aryl sulfonamide groups can be incorporated into drug design as efficient cell-penetrating motifs in vivo and reveal the unexpected biological consequences of atropisomerism.
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Affiliation(s)
- Claire Donohoe
- CQC, Coimbra Chemistry Center, University of Coimbra, Rua Larga, Coimbra 3004-535, Portugal.,Medicinal Chemistry, Trinity Translational Medicine Institute, Trinity Centre for Health Sciences, St. James's Hospital, Trinity College Dublin, The University of Dublin, Dublin 8, Ireland
| | - Fábio A Schaberle
- CQC, Coimbra Chemistry Center, University of Coimbra, Rua Larga, Coimbra 3004-535, Portugal
| | - Fábio M S Rodrigues
- CQC, Coimbra Chemistry Center, University of Coimbra, Rua Larga, Coimbra 3004-535, Portugal
| | - Nuno P F Gonçalves
- Luzitin SA, Ed. Bluepharma, S. Martinho do Bispo, Coimbra 3045-016, Portugal
| | - Christopher J Kingsbury
- School of Chemistry, Chair of Organic Chemistry, Trinity Biomedical Sciences Institute, Trinity College Dublin, The University of Dublin, 152-160 Pearse Street, Dublin 2, Ireland
| | - Mariette M Pereira
- CQC, Coimbra Chemistry Center, University of Coimbra, Rua Larga, Coimbra 3004-535, Portugal
| | - Mathias O Senge
- Medicinal Chemistry, Trinity Translational Medicine Institute, Trinity Centre for Health Sciences, St. James's Hospital, Trinity College Dublin, The University of Dublin, Dublin 8, Ireland.,Institute for Advanced Study (TUM-IAS), Technical University of Munich, Lichtenbergstrasse 2a, Garching 85748, Germany
| | - Lígia C Gomes-da-Silva
- CQC, Coimbra Chemistry Center, University of Coimbra, Rua Larga, Coimbra 3004-535, Portugal
| | - Luis G Arnaut
- CQC, Coimbra Chemistry Center, University of Coimbra, Rua Larga, Coimbra 3004-535, Portugal
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20
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EFR3 and phosphatidylinositol 4-kinase IIIα regulate insulin-stimulated glucose transport and GLUT4 dispersal in 3T3-L1 adipocytes. Biosci Rep 2022; 42:231469. [PMID: 35735144 PMCID: PMC9272592 DOI: 10.1042/bsr20221181] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 06/21/2022] [Accepted: 06/22/2022] [Indexed: 11/17/2022] Open
Abstract
Insulin stimulates glucose transport in muscle and adipocytes. This is achieved by regulated delivery of intracellular glucose transporter (GLUT4)-containing vesicles to the plasma membrane where they dock and fuse, resulting in increased cell surface GLUT4 levels. Recent work identified a potential further regulatory step, in which insulin increases the dispersal of GLUT4 in the plasma membrane away from the sites of vesicle fusion. EFR3 is a scaffold protein that facilitates localization of phosphatidylinositol 4-kinase type IIIα to the cell surface. Here we show that knockdown of EFR3 or phosphatidylinositol 4-kinase type IIIα impairs insulin-stimulated glucose transport in adipocytes. Using direct stochastic reconstruction microscopy, we also show that EFR3 knockdown impairs insulin stimulated GLUT4 dispersal in the plasma membrane. We propose that EFR3 plays a previously unidentified role in controlling insulin-stimulated glucose transport by facilitating dispersal of GLUT4 within the plasma membrane.
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21
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Zheng S, Zheng B, Liu Z, Ma X, Liu X, Yao X, Wei W, Fu C. The Cdc42 GTPase activating protein Rga6 promotes the cortical localization of Septin. J Cell Sci 2022; 135:274388. [DOI: 10.1242/jcs.259228] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 01/06/2022] [Indexed: 11/20/2022] Open
Abstract
Septins are a family of filament-forming GTP-binding proteins that regulate fundamental cellular activities such as cytokinesis and cell polarity. In general, Septin filaments function as barriers and scaffolds on the cell cortex. However, little is known about the mechanism that governs the recruitment and localization of the Septin complex to the cell cortex. Here, we identified the Cdc42 GTPase activating protein Rga6 as a key protein involved in promoting the localization of the Septin complex to the cell cortex in the fission yeast Schizosaccharomyces pombe. Rga6 interacts with the Septin complex and partially colocalizes with the Septin complex on the cell cortex. Live-cell microscopic analysis further showed Septin enrichment at the cortical regions adjacent to the growing cell tip. The Septin enrichment likely plays a crucial role in confining active Cdc42 to the growing cell tip. Hence, our findings support a model that Rga6 regulates polarized cell growth partly through promoting targeted localization of the Septin complex on the cell cortex.
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Affiliation(s)
- Shengnan Zheng
- Ministry of Education Key Laboratory for Cellular Dynamics, CAS Center for Excellence in Molecular Cell Sciences, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, 230027 Hefei, P.R. China
| | - Biyu Zheng
- Ministry of Education Key Laboratory for Cellular Dynamics, CAS Center for Excellence in Molecular Cell Sciences, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, 230027 Hefei, P.R. China
| | - Zhenbang Liu
- Division of Life Sciences and Medicine, University of Science and Technology of China, 230027 Hefei, P.R. China
| | - Xiaopeng Ma
- Department of General Surgery, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230001, PR China
| | - Xing Liu
- Ministry of Education Key Laboratory for Cellular Dynamics, CAS Center for Excellence in Molecular Cell Sciences, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, 230027 Hefei, P.R. China
| | - Xuebiao Yao
- Ministry of Education Key Laboratory for Cellular Dynamics, CAS Center for Excellence in Molecular Cell Sciences, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, 230027 Hefei, P.R. China
| | - Wenfan Wei
- Ministry of Education Key Laboratory for Cellular Dynamics, CAS Center for Excellence in Molecular Cell Sciences, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, 230027 Hefei, P.R. China
| | - Chuanhai Fu
- Ministry of Education Key Laboratory for Cellular Dynamics, CAS Center for Excellence in Molecular Cell Sciences, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, 230027 Hefei, P.R. China
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22
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Abbineni PS, Briguglio JS, Chapman ER, Holz RW, Axelrod D. VAMP2 and synaptotagmin mobility in chromaffin granule membranes: implications for regulated exocytosis. Mol Biol Cell 2021; 33:ar53. [PMID: 34851717 PMCID: PMC9265163 DOI: 10.1091/mbc.e21-10-0494] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Granule-plasma membrane docking and fusion can only occur when proteins that enable these reactions are present at the granule-plasma membrane contact. Thus, the mobility of granule membrane proteins may influence docking, and membrane fusion. We measured the mobility of vesicle associated membrane protein 2 (VAMP2), synaptotagmin 1 (Syt1), and synaptotagmin 7 (Syt7) in chromaffin granule membranes in living chromaffin cells. We used a method that is not limited by standard optical resolution. A bright flash of strongly decaying evanescent field produced by total internal reflection (TIR) was used to photobleach GFP-labeled proteins in the granule membrane. Fluorescence recovery occurs as unbleached protein in the granule membrane distal from the glass interface diffuses into the more bleached proximal regions, enabling the measurement of diffusion coefficients. We found that VAMP2-EGFP and Syt7-EGFP are mobile with a diffusion coefficient of approximately 3 × 10-10 cm2/s. Syt1-EGFP mobility was below the detection limit. Utilizing these diffusion parameters, we estimated the time required for these proteins to arrive at docking and nascent fusion sites to be many tens of milliseconds. Our analyses raise the possibility that the diffusion characteristics of VAMP2 and Syt proteins could be a factor that influences the rate of exocytosis.
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Affiliation(s)
- Prabhodh S Abbineni
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan.,Department of Pharmacology, University of Michigan, Ann Arbor, Michigan
| | - Joseph S Briguglio
- Howard Hughes Medical Institute, Department of Neuroscience, University of Wisconsin, Madison, WI
| | - Edwin R Chapman
- Howard Hughes Medical Institute, Department of Neuroscience, University of Wisconsin, Madison, WI
| | - Ronald W Holz
- Department of Pharmacology, University of Michigan, Ann Arbor, Michigan
| | - Daniel Axelrod
- Department of Pharmacology, University of Michigan, Ann Arbor, Michigan.,Department of Physics, University of Michigan, Ann Arbor, Michigan
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23
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Sallaberry CA, Voss BJ, Majewski J, Biernat J, Mandelkow E, Chi EY, Vander Zanden CM. Tau and Membranes: Interactions That Promote Folding and Condensation. Front Cell Dev Biol 2021; 9:725241. [PMID: 34621743 PMCID: PMC8491580 DOI: 10.3389/fcell.2021.725241] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 08/31/2021] [Indexed: 12/15/2022] Open
Abstract
Tau misfolding and assembly is linked to a number of neurodegenerative diseases collectively described as tauopathies, including Alzheimer’s disease (AD) and Parkinson’s disease. Anionic cellular membranes, such as the cytosolic leaflet of the plasma membrane, are sites that concentrate and neutralize tau, primarily due to electrostatic interactions with tau’s microtubule binding repeat domain (RD). In addition to electrostatic interactions with lipids, tau also has interactions with membrane proteins, which are important for tau’s cellular functions. Tau also interacts with lipid tails to facilitate direct translocation across the membrane and can form stable protein-lipid complexes involved in cell-to-cell transport. Concentrated tau monomers at the membrane surface can form reversible condensates, change secondary structures, and induce oligomers, which may eventually undergo irreversible crosslinking and fibril formation. These β-sheet rich tau structures are capable of disrupting membrane organization and are toxic in cell-based assays. Given the evidence for relevant membrane-based tau assembly, we review the emerging hypothesis that polyanionic membranes may serve as a site for phase-separated tau condensation. Membrane-mediated phase separation may have important implications for regulating tau folding/misfolding, and may be a powerful mechanism to spatially direct tau for native membrane-mediated functions.
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Affiliation(s)
- Chad A Sallaberry
- Department of Chemistry & Biochemistry, University of Colorado Colorado Springs, Colorado Springs, CO, United States
| | - Barbie J Voss
- Department of Chemistry & Biochemistry, University of Colorado Colorado Springs, Colorado Springs, CO, United States
| | - Jaroslaw Majewski
- Division of Molecular and Cellular Biosciences, National Science Foundation, Alexandria, VA, United States.,Department of Chemical & Biological Engineering, Center for Biomedical Engineering, The University of New Mexico, Albuquerque, NM, United States.,Theoretical Biology and Biophysics Division, Los Alamos National Laboratory, Los Alamos, NM, United States
| | - Jacek Biernat
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Eckhard Mandelkow
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.,Center of Advanced European Studies and Research (CAESAR) Center, Bonn, Germany.,Department of Neurodegenerative Disease and Geriatric Psychiatry, Medical School, University of Bonn, Bonn, Germany
| | - Eva Y Chi
- Department of Chemical & Biological Engineering, Center for Biomedical Engineering, The University of New Mexico, Albuquerque, NM, United States
| | - Crystal M Vander Zanden
- Department of Chemistry & Biochemistry, University of Colorado Colorado Springs, Colorado Springs, CO, United States
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24
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Control of membrane protein homeostasis by a chaperone-like glial cell adhesion molecule at multiple subcellular locations. Sci Rep 2021; 11:18435. [PMID: 34531445 PMCID: PMC8446001 DOI: 10.1038/s41598-021-97777-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 08/24/2021] [Indexed: 01/17/2023] Open
Abstract
The significance of crosstalks among constituents of plasma membrane protein clusters/complexes in cellular proteostasis and protein quality control (PQC) remains incompletely understood. Examining the glial (enriched) cell adhesion molecule (CAM), we demonstrate its chaperone-like role in the biosynthetic processing of the megalencephalic leukoencephalopathy with subcortical cyst 1 (MLC1)-heteromeric regulatory membrane protein complex, as well as the function of the GlialCAM/MLC1 signalling complex. We show that in the absence of GlialCAM, newly synthesized MLC1 molecules remain unfolded and are susceptible to polyubiquitination-dependent proteasomal degradation at the endoplasmic reticulum. At the plasma membrane, GlialCAM regulates the diffusional partitioning and endocytic dynamics of cluster members, including the ClC-2 chloride channel and MLC1. Impaired folding and/or expression of GlialCAM or MLC1 in the presence of diseases causing mutations, as well as plasma membrane tethering compromise the functional expression of the cluster, leading to compromised endo-lysosomal organellar identity. In addition, the enlarged endo-lysosomal compartments display accelerated acidification, ubiquitinated cargo-sorting and impaired endosomal recycling. Jointly, these observations indicate an essential and previously unrecognized role for CAM, where GliaCAM functions as a PQC factor for the MLC1 signalling complex biogenesis and possess a permissive role in the membrane dynamic and cargo sorting functions with implications in modulations of receptor signalling.
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25
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Kamalesh K, Scher N, Biton T, Schejter ED, Shilo BZ, Avinoam O. Exocytosis by vesicle crumpling maintains apical membrane homeostasis during exocrine secretion. Dev Cell 2021; 56:1603-1616.e6. [PMID: 34102104 PMCID: PMC8191493 DOI: 10.1016/j.devcel.2021.05.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 03/17/2021] [Accepted: 05/06/2021] [Indexed: 12/14/2022]
Abstract
Exocrine secretion commonly employs micron-scale vesicles that fuse to a limited apical surface, presenting an extreme challenge for maintaining membrane homeostasis. Using Drosophila melanogaster larval salivary glands, we show that the membranes of fused vesicles undergo actomyosin-mediated folding and retention, which prevents them from incorporating into the apical surface. In addition, the diffusion of proteins and lipids between the fused vesicle and the apical surface is limited. Actomyosin contraction and membrane crumpling are essential for recruiting clathrin-mediated endocytosis to clear the retained vesicular membrane. Finally, we also observe membrane crumpling in secretory vesicles of the mouse exocrine pancreas. We conclude that membrane sequestration by crumpling followed by targeted endocytosis of the vesicular membrane, represents a general mechanism of exocytosis that maintains membrane homeostasis in exocrine tissues that employ large secretory vesicles.
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Affiliation(s)
- Kumari Kamalesh
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel; Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Nadav Scher
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Tom Biton
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel; Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Eyal D Schejter
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Ben-Zion Shilo
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel.
| | - Ori Avinoam
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel.
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26
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Kamali Shahri SM, Sharifi S, Mahmoudi M. Interdependency of influential parameters in therapeutic nanomedicine. Expert Opin Drug Deliv 2021; 18:1379-1394. [PMID: 33887999 DOI: 10.1080/17425247.2021.1921732] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Introduction:Current challenges to successful clinical translation of therapeutic nanomedicine have discouraged many stakeholders, including patients. Significant effort has been devoted to uncovering the reasons behind the less-than-expected success, beyond failures or ineffectiveness, of therapeutic nanomedicine products (e.g. cancer nanomedicine). Until we understand and address the factors that limit the safety and efficacy of NPs, both individually and in combination, successful clinical development will lag.Areas covered:This review highlights the critical roles of interdependent factors affecting the safety and therapeutic efficacy of therapeutic NPs for drug delivery applications.Expert opinion:Deep analysis of the current nanomedical literature reveals ahistory of unanticipated complexity by awide range of stakeholders including researchers. In the manufacture of nanomedicines themselves, there have been persistent difficulties with reproducibility and batch-to-batch variation. The unanticipated complexity and interdependency of nano-bio parameters has delayed our recognition of important factors affecting the safety and therapeutic efficacy of nanomedicine products. These missteps have had many factors including our lack of understanding of the interdependency of various factors affecting the biological identity and fate of NPs and biased interpretation of data. All these issues could raise significant concern regarding the reproducibility- or even the validity- of past publications that in turn formed the basis of many clinical trials of therapeutic nanomedicines. Therefore, the individual and combined effects of previously overlooked factors on the safety and therapeutic efficacy of NPs need to be fully considered in nanomedicine reports and product development.
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Affiliation(s)
- Seyed Mehdi Kamali Shahri
- Department of Radiology and Precision Health Program, College of Human Medicine, Michigan State University, East Lansing, MI, USA
| | - Shahriar Sharifi
- Department of Radiology and Precision Health Program, College of Human Medicine, Michigan State University, East Lansing, MI, USA
| | - Morteza Mahmoudi
- Department of Radiology and Precision Health Program, College of Human Medicine, Michigan State University, East Lansing, MI, USA
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Conduit SE, Davies EM, Fulcher AJ, Oorschot V, Mitchell CA. Superresolution Microscopy Reveals Distinct Phosphoinositide Subdomains Within the Cilia Transition Zone. Front Cell Dev Biol 2021; 9:634649. [PMID: 33996795 PMCID: PMC8120242 DOI: 10.3389/fcell.2021.634649] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Accepted: 04/06/2021] [Indexed: 11/30/2022] Open
Abstract
Primary cilia are evolutionary conserved microtubule-based organelles that protrude from the surface of most mammalian cells. Phosphoinositides (PI) are membrane-associated signaling lipids that regulate numerous cellular events via the recruitment of lipid-binding effectors. The temporal and spatial membrane distribution of phosphoinositides is regulated by phosphoinositide kinases and phosphatases. Recently phosphoinositide signaling and turnover has been observed at primary cilia. However, the precise localization of the phosphoinositides to specific ciliary subdomains remains undefined. Here we use superresolution microscopy (2D stimulated emission depletion microscopy) to map phosphoinositide distribution at the cilia transition zone. PI(3,4,5)P3 and PI(4,5)P2 localized to distinct subregions of the transition zone in a ring-shape at the inner transition zone membrane. Interestingly, the PI(3,4,5)P3 subdomain was more distal within the transition zone relative to PtdIns(4,5)P2. The phosphoinositide effector kinase pAKT(S473) localized in close proximity to these phosphoinositides. The inositol polyphosphate 5-phosphatase, INPP5E, degrades transition zone phosphoinositides, however, studies of fixed cells have reported recombinant INPP5E localizes to the ciliary axoneme, distant from its substrates. Notably, here using live cell imaging and optimized fixation/permeabilization protocols INPP5E was found concentrated at the cilia base, in a distribution characteristic of the transition zone in a ring-shaped domain of similar dimensions to the phosphoinositides. Collectively, this superresolution map places the phosphoinositides in situ with the transition zone proteins and reveals that INPP5E also likely localizes to a subdomain of the transition zone membrane, where it is optimally situated to control local phosphoinositide metabolism.
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Affiliation(s)
- Sarah E Conduit
- Cancer Program, Monash Biomedicine Discovery Institute, Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia
| | - Elizabeth M Davies
- Cancer Program, Monash Biomedicine Discovery Institute, Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia
| | - Alex J Fulcher
- Monash Micro Imaging, Monash University, Clayton, VIC, Australia
| | - Viola Oorschot
- Monash Ramaciotti Centre for Structural Cryo-Electron Microscopy, Monash University, Clayton, VIC, Australia
| | - Christina A Mitchell
- Cancer Program, Monash Biomedicine Discovery Institute, Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia
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Mylvaganam S, Riedl M, Vega A, Collins RF, Jaqaman K, Grinstein S, Freeman SA. Stabilization of Endothelial Receptor Arrays by a Polarized Spectrin Cytoskeleton Facilitates Rolling and Adhesion of Leukocytes. Cell Rep 2021; 31:107798. [PMID: 32579925 PMCID: PMC7548125 DOI: 10.1016/j.celrep.2020.107798] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 04/15/2020] [Accepted: 06/01/2020] [Indexed: 12/15/2022] Open
Abstract
Multivalent complexes of endothelial adhesion receptors (e.g., selectins) engage leukocytes to orchestrate their migration to inflamed tissues. Proper anchorage and sufficient density (clustering) of endothelial receptors are required for efficient leukocyte capture and rolling. We demonstrate that a polarized spectrin network dictates the stability of the endothelial cytoskeleton, which is attached to the apical membrane, at least in part, by the abundant transmembrane protein CD44. Single-particle tracking revealed that CD44 undergoes prolonged periods of immobilization as it tethers to the cytoskeleton. The CD44-spectrin "picket fence" alters the behavior of bystander molecules-notably, selectins-curtailing their mobility, inducing their apical accumulation, and favoring their clustering within caveolae. Accordingly, depletion of either spectrin or CD44 virtually eliminated leukocyte rolling and adhesion to the endothelium. Our results indicate that a unique spectrin-based apical cytoskeleton tethered to transmembrane pickets-notably, CD44-is essential for proper extravasation of leukocytes in response to inflammation.
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Affiliation(s)
- Sivakami Mylvaganam
- Program in Cell Biology, Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, 686 Bay Street, 19-9800, Toronto, ON M5G 0A4, Canada; Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada
| | - Magdalena Riedl
- Program in Cell Biology, Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, 686 Bay Street, 19-9800, Toronto, ON M5G 0A4, Canada
| | - Anthony Vega
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Lyda Hill Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Richard F Collins
- Program in Cell Biology, Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, 686 Bay Street, 19-9800, Toronto, ON M5G 0A4, Canada
| | - Khuloud Jaqaman
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Lyda Hill Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Sergio Grinstein
- Program in Cell Biology, Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, 686 Bay Street, 19-9800, Toronto, ON M5G 0A4, Canada; Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada; Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON M5B 1W8, Canada.
| | - Spencer A Freeman
- Program in Cell Biology, Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, 686 Bay Street, 19-9800, Toronto, ON M5G 0A4, Canada; Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada.
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Mela A, Momany M. Septins coordinate cell wall integrity and lipid metabolism in a sphingolipid-dependent process. J Cell Sci 2021; 135:256543. [PMID: 33912961 DOI: 10.1242/jcs.258336] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 12/31/2020] [Indexed: 01/09/2023] Open
Abstract
Septins colocalize with membrane sterol-rich regions and facilitate recruitment of cell wall synthases during wall remodeling. We show that null mutants missing an Aspergillus nidulans core septin present in hexamers and octamers (ΔaspAcdc11, ΔaspBcdc3 or ΔaspCcdc12) are sensitive to multiple cell wall-disturbing agents that activate the cell wall integrity MAPK pathway. The null mutant missing the octamer-exclusive core septin (ΔaspDcdc10) showed similar sensitivity, but only to a single cell wall-disturbing agent and the null mutant missing the noncore septin (ΔaspE) showed only very mild sensitivity to a different single agent. Core septin mutants showed changes in wall polysaccharide composition and chitin synthase localization. Mutants missing any of the five septins resisted ergosterol-disrupting agents. Hexamer mutants showed increased sensitivity to sphingolipid-disrupting agents. Core septins mislocalized after treatment with sphingolipid-disrupting agents, but not after ergosterol-disrupting agents. Our data suggest that the core septins are involved in cell wall integrity signaling, that all five septins are involved in monitoring ergosterol metabolism, that the hexamer septins are required for sphingolipid metabolism and that septins require sphingolipids to coordinate the cell wall integrity response.
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Affiliation(s)
- Alexander Mela
- Fungal Biology Group and Plant Biology Department, University of Georgia, 2502 Miller Plant Science Building, Athens, GA 30602, USA
| | - Michelle Momany
- Fungal Biology Group and Plant Biology Department, University of Georgia, 2502 Miller Plant Science Building, Athens, GA 30602, USA
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30
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Obashi K, Taraska JW, Okabe S. The role of molecular diffusion within dendritic spines in synaptic function. J Gen Physiol 2021; 153:e202012814. [PMID: 33720306 PMCID: PMC7967910 DOI: 10.1085/jgp.202012814] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 02/16/2021] [Indexed: 12/21/2022] Open
Abstract
Spines are tiny nanoscale protrusions from dendrites of neurons. In the cortex and hippocampus, most of the excitatory postsynaptic sites reside in spines. The bulbous spine head is connected to the dendritic shaft by a thin membranous neck. Because the neck is narrow, spine heads are thought to function as biochemically independent signaling compartments. Thus, dynamic changes in the composition, distribution, mobility, conformations, and signaling properties of molecules contained within spines can account for much of the molecular basis of postsynaptic function and regulation. A major factor in controlling these changes is the diffusional properties of proteins within this small compartment. Advances in measurement techniques using fluorescence microscopy now make it possible to measure molecular diffusion within single dendritic spines directly. Here, we review the regulatory mechanisms of diffusion in spines by local intra-spine architecture and discuss their implications for neuronal signaling and synaptic plasticity.
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Affiliation(s)
- Kazuki Obashi
- Biochemistry and Biophysics Center, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD
| | - Justin W. Taraska
- Biochemistry and Biophysics Center, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD
| | - Shigeo Okabe
- Department of Cellular Neurobiology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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31
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Srivastava N, Nader GPDF, Williart A, Rollin R, Cuvelier D, Lomakin A, Piel M. Nuclear fragility, blaming the blebs. Curr Opin Cell Biol 2021; 70:100-108. [PMID: 33662810 DOI: 10.1016/j.ceb.2021.01.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 01/15/2021] [Accepted: 01/20/2021] [Indexed: 12/11/2022]
Abstract
Although textbook pictures depict the cell nucleus as a simple ovoid object, it is now clear that it adopts a large variety of shapes in tissues. When cells deform, because of cell crowding or migration through dense matrices, the nucleus is subjected to large constraints that alter its shape. In this review, we discuss recent studies related to nuclear fragility, focusing on the surprising finding that the nuclear envelope can form blebs. Contrary to the better-known plasma membrane blebs, nuclear blebs are unstable and almost systematically lead to nuclear envelope opening and uncontrolled nucleocytoplasmic mixing. They expand, burst, and repair repeatedly when the nucleus is strongly deformed. Although blebs are a major source of nuclear instability, they are poorly understood so far, which calls for more in-depth studies of these structures.
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Affiliation(s)
- Nishit Srivastava
- Institut Curie and Institut Pierre Gilles de Gennes, PSL Research University, CNRS, UMR 144, Paris, France
| | | | - Alice Williart
- Institut Curie and Institut Pierre Gilles de Gennes, PSL Research University, CNRS, UMR 144, Paris, France
| | - Romain Rollin
- Institut Curie, PSL Research University, CNRS, UMR 168, Paris France
| | - Damien Cuvelier
- Institut Curie and Institut Pierre Gilles de Gennes, PSL Research University, CNRS, UMR 144, Paris, France
| | - Alexis Lomakin
- St. Anna Children's Cancer Research Institute, Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, And Medical University of Vienna, Vienna, Austria
| | - Matthieu Piel
- Institut Curie and Institut Pierre Gilles de Gennes, PSL Research University, CNRS, UMR 144, Paris, France.
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32
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Mitchell MJ, Billingsley MM, Haley RM, Wechsler ME, Peppas NA, Langer R. Engineering precision nanoparticles for drug delivery. Nat Rev Drug Discov 2020; 20:101-124. [PMID: 33277608 PMCID: PMC7717100 DOI: 10.1038/s41573-020-0090-8] [Citation(s) in RCA: 2689] [Impact Index Per Article: 672.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/16/2020] [Indexed: 12/12/2022]
Abstract
In recent years, the development of nanoparticles has expanded into a broad range of clinical applications. Nanoparticles have been developed to overcome the limitations of free therapeutics and navigate biological barriers — systemic, microenvironmental and cellular — that are heterogeneous across patient populations and diseases. Overcoming this patient heterogeneity has also been accomplished through precision therapeutics, in which personalized interventions have enhanced therapeutic efficacy. However, nanoparticle development continues to focus on optimizing delivery platforms with a one-size-fits-all solution. As lipid-based, polymeric and inorganic nanoparticles are engineered in increasingly specified ways, they can begin to be optimized for drug delivery in a more personalized manner, entering the era of precision medicine. In this Review, we discuss advanced nanoparticle designs utilized in both non-personalized and precision applications that could be applied to improve precision therapies. We focus on advances in nanoparticle design that overcome heterogeneous barriers to delivery, arguing that intelligent nanoparticle design can improve efficacy in general delivery applications while enabling tailored designs for precision applications, thereby ultimately improving patient outcome overall. Advances in nanoparticle design could make substantial contributions to personalized and non-personalized medicine. In this Review, Langer, Mitchell, Peppas and colleagues discuss advances in nanoparticle design that overcome heterogeneous barriers to delivery, as well as the challenges in translating these design improvements into personalized medicine approaches.
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Affiliation(s)
- Michael J Mitchell
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA. .,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA. .,Institute for Immunology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA. .,Cardiovascular Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA. .,Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| | | | - Rebecca M Haley
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Marissa E Wechsler
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Nicholas A Peppas
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA. .,Department of Chemical Engineering, The University of Texas at Austin, Austin, TX, USA. .,Department of Pediatrics, The University of Texas at Austin, Austin, TX, USA. .,Department of Surgery and Perioperative Care, The University of Texas at Austin, Austin, TX, USA. .,Department of Molecular Pharmaceutics and Drug Delivery, The University of Texas at Austin, Austin, TX, USA.
| | - Robert Langer
- Department of Chemical Engineering and Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA.
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33
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Martin-Fernandez ML. A brief history of the octopus imaging facility to celebrate its 10th anniversary. J Microsc 2020; 281:3-15. [PMID: 33111321 DOI: 10.1111/jmi.12974] [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: 08/06/2020] [Revised: 10/19/2020] [Accepted: 10/23/2020] [Indexed: 11/27/2022]
Abstract
Octopus (Optics Clustered to OutPut Unique Solutions) celebrated in June 2020 its 10th birthday. Based at Harwell, near Oxford, Octopus is an open access, peer reviewed, national imaging facility that offers successful U.K. applicants supported access to single molecule imaging, confocal microscopy, several flavours of superresolution imaging, light sheet microscopy, optical trapping and cryoscanning electron microscopy. Managed by a multidisciplinary team, Octopus has so far assisted >100 groups of U.K. and international researchers. Cross-fertilisation across fields proved to be a strong propeller of success underpinned by combining access to top-end instrumentation with a strong programme of imaging hardware and software developments. How Octopus was born, and highlights of the multidisciplinary output produced during its 10-year journey are reviewed below, with the aim of celebrating a myriad of collaborations with the U.K. scientific community, and reflecting on their scientific and societal impact.
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Affiliation(s)
- M L Martin-Fernandez
- Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell, Didcot, Oxford, U.K
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34
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Li Y, Yan H, Zhang Y, Li Q, Yu L, Li Q, Liu C, Xie Y, Chen K, Ye F, Wang K, Chen L, Ding Y. Alterations of the Gut Microbiome Composition and Lipid Metabolic Profile in Radiation Enteritis. Front Cell Infect Microbiol 2020; 10:541178. [PMID: 33194790 PMCID: PMC7609817 DOI: 10.3389/fcimb.2020.541178] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 09/28/2020] [Indexed: 12/26/2022] Open
Abstract
Radiation enteritis (RE) is a common complication in cancer patients receiving radiotherapy. Although studies have shown the changes of this disease at clinical, pathological and other levels, the dynamic characteristics of local microbiome and metabolomics are hitherto unknown. We aimed to examine the multi-omics features of the gut microecosystem, determining the functional correlation between microbiome and lipid metabolites during RE activity. By delivering single high-dose irradiation, a RE mouse model was established. High-throughput 16S rDNA sequencing and global lipidomics analysis were performed to examine microbial and lipidomic profile changes in the gut microecosystem. Spearman correlation analysis was used to determine the functional correlation between bacteria and metabolites. Clinical samples were collected to validate the above observations. During RE activity, the intestinal inflammation of the mice was confirmed by typical signs, symptoms, imaging findings and pathological evidences. 16S datasets revealed that localized irradiation dramatically altered the gut microbial composition, resulting in a decrease ratio of Bacteroidetes to Firmicutes. Lipidomics analysis indicated the remarkable lipidomic profile changes in enteric epithelial barrier, determining that glycerophospholipids metabolism was correlated to RE progression with the highest relevance. Spearman correlation analysis identified that five bacteria-metabolite pairs showed the most significant functional correlation in RE, including Alistipes-PC(36:0e), Bacteroides-DG(18:0/20:4), Dubosiella-PC(35:2), Eggerthellaceae-PC(35:6), and Escherichia-Shigella-TG(18:2/18:2/20:4). These observations were partly confirmed in human specimens. Our study provided a comprehensive description of microbiota dysbiosis and lipid metabolic disorders in RE, suggesting strategies to change local microecosystem to relieve radiation injury and maintain homeostasis.
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Affiliation(s)
- Yiyi Li
- Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Hongmei Yan
- Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, China.,Cancer Research Institute, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Yaowei Zhang
- Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Qingping Li
- Division of Hepatobiliopancreatic Surgery, Department of General Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Lu Yu
- Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Qianyu Li
- Medical Imaging Specialty, The First School of Clinical Medicine, Southern Medical University, Guangzhou, China
| | - Cuiting Liu
- Central Laboratory, Southern Medical University, Guangzhou, China
| | - Yuwen Xie
- Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, China.,Department of Pathology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Keli Chen
- HuiQiao Medical Center, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Feng Ye
- Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Kai Wang
- Division of Hepatobiliopancreatic Surgery, Department of General Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Longhua Chen
- Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Yi Ding
- Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, China
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35
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Yan R, Chen K, Xu K. Probing Nanoscale Diffusional Heterogeneities in Cellular Membranes through Multidimensional Single-Molecule and Super-Resolution Microscopy. J Am Chem Soc 2020; 142:18866-18873. [PMID: 33084318 DOI: 10.1021/jacs.0c08426] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Diffusion properties notably determine the behavior of biomembranes. Here we report the concurrent nanoscale fine-mapping of membrane topography, diffusivity, and packing order in live mammalian cells through a synergy of single-molecule and super-resolution methods. By identifying a bright, lipophilic fluorescence turn-on probe that enables sustained single-molecule imaging of cellular membranes under stroboscopic excitation, we accumulate the positions and transient displacements of >106 probe molecules to achieve super-resolution topography and diffusivity mapping. We thus determine a trend that the membrane diffusivity drops with increased lipid packing order when comparing the endoplasmic reticulum (ER) membrane, plasma membrane, and nanodomains induced by cholera toxin B. Utilizing our nanoscale mapping capability, we further unveil reduced diffusivity in the ER membrane at ER-plasma membrane contact sites. By next integrating spectrally resolved single-molecule imaging, we show that this localized diffusion slowdown is not due to altered lipid packing order but may instead be attributed to local protein crowding. Our integrated multidimensional single-molecule approach thus unveils and differentiates between nanoscale diffusional heterogeneities of different origins in live-cell membranes.
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Affiliation(s)
- Rui Yan
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chan Zuckerberg Biohub, San Francisco, California 94158, United States
| | - Kun Chen
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chan Zuckerberg Biohub, San Francisco, California 94158, United States
| | - Ke Xu
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chan Zuckerberg Biohub, San Francisco, California 94158, United States
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36
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CD99-PTPN12 Axis Suppresses Actin Cytoskeleton-Mediated Dimerization of Epidermal Growth Factor Receptor. Cancers (Basel) 2020; 12:cancers12102895. [PMID: 33050232 PMCID: PMC7599698 DOI: 10.3390/cancers12102895] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 09/30/2020] [Accepted: 10/05/2020] [Indexed: 12/18/2022] Open
Abstract
Simple Summary The epidermal growth factor receptor (EGFR) is activated through growth factor-dependent dimerization accompanied by functional reorganization of the actin cytoskeleton. Lee et al. demonstrate that CD99 activation by agonist ligands inhibits epidermal growth factor (EGF)-induced EGFR dimerization through impairment of cytoskeletal reorganization by protein tyrosine phosphatase non-receptor type 12 (PTPN12)-dependent c-Src/focal adhesion kinase (FAK) inactivation, thereby suppressing breast cancer growth. Abstract The epidermal growth factor receptor (EGFR), a member of ErbB receptor tyrosine kinase (RTK) family, is activated through growth factor-induced reorganization of the actin cytoskeleton and subsequent dimerization. We herein explored the molecular mechanism underlying the suppression of ligand-induced EGFR dimerization by CD99 agonists and its relevance to tumor growth in vivo. Epidermal growth factor (EGF) activated the formation of c-Src/focal adhesion kinase (FAK)-mediated intracellular complex and subsequently induced RhoA-and Rac1-mediated actin remodeling, resulting in EGFR dimerization and endocytosis. In contrast, CD99 agonist facilitated FAK dephosphorylation through the HRAS/ERK/PTPN12 signaling pathway, leading to inhibition of actin cytoskeletal reorganization via inactivation of the RhoA and Rac1 signaling pathways. Moreover, CD99 agonist significantly suppressed tumor growth in a BALB/c mouse model injected with MDA-MB-231 human breast cancer cells. Taken together, these results indicate that CD99-derived agonist ligand inhibits epidermal growth factor (EGF)-induced EGFR dimerization through impairment of cytoskeletal reorganization by PTPN12-dependent c-Src/FAK inactivation, thereby suppressing breast cancer growth.
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37
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Otani T, Furuse M. Tight Junction Structure and Function Revisited. Trends Cell Biol 2020; 30:805-817. [PMID: 32891490 DOI: 10.1016/j.tcb.2020.08.004] [Citation(s) in RCA: 295] [Impact Index Per Article: 73.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 08/03/2020] [Accepted: 08/06/2020] [Indexed: 12/14/2022]
Abstract
Tight junctions (TJs) are intercellular junctions critical for building the epithelial barrier and maintaining epithelial polarity. The claudin family of membrane proteins play central roles in TJ structure and function. However, recent findings have uncovered claudin-independent aspects of TJ structure and function, and additional players including junctional adhesion molecules (JAMs), membrane lipids, phase separation of the zonula occludens (ZO) family of scaffolding proteins, and mechanical force have been shown to play important roles in TJ structure and function. In this review, we discuss how these new findings have the potential to transform our understanding of TJ structure and function, and how the intricate network of TJ proteins and membrane lipids dynamically interact to drive TJ assembly.
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Affiliation(s)
- Tetsuhisa Otani
- Division of Cell Structure, National Institute for Physiological Sciences, Okazaki, Aichi 444-8787, Japan; Department of Physiological Sciences, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi 444-8787, Japan.
| | - Mikio Furuse
- Division of Cell Structure, National Institute for Physiological Sciences, Okazaki, Aichi 444-8787, Japan; Department of Physiological Sciences, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi 444-8787, Japan
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38
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Grebnev G, Cvitkovic M, Fritz C, Cai G, Smith AS, Kost B. Quantitative Structural Organization of Bulk Apical Membrane Traffic in Pollen Tubes. PLANT PHYSIOLOGY 2020; 183:1559-1585. [PMID: 32482906 PMCID: PMC7401101 DOI: 10.1104/pp.20.00380] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 05/15/2020] [Indexed: 05/13/2023]
Abstract
Pollen tube tip growth depends on balancing secretion of cell wall material with endocytic recycling of excess material incorporated into the plasma membrane (PM). The classical model of tip growth, which predicts bulk secretion, occurs apically, and is compensated by subapical endocytosis, has been challenged in recent years. Many signaling proteins and lipids with important functions in the regulation of membrane traffic underlying tip growth associate with distinct regions of the pollen tube PM, and understanding the mechanisms responsible for the targeting of these regulatory factors to specific PM domains requires quantitative information concerning the sites of bulk secretion and endocytosis. Here, we quantitatively characterized the spatial organization of membrane traffic during tip growth by analyzing steady-state distributions and dynamics of FM4-64-labeled lipids and YFP-tagged transmembrane (TM) proteins in tobacco (Nicotiana tabacum) pollen tubes growing normally or treated with Brefeldin A to block secretion. We established that (1) secretion delivers TM proteins and recycled membrane lipids to the same apical PM domain, and (2) FM4-64-labeled lipids, but not the analyzed TM proteins, undergo endocytic recycling within a clearly defined subapical region. We mathematically modeled the steady-state PM distributions of all analyzed markers to better understand differences between them and to support the experimental data. Finally, we mapped subapical F-actin fringe and trans-Golgi network positioning relative to sites of bulk secretion and endocytosis to further characterize functions of these structures in apical membrane traffic. Our results support and further define the classical model of apical membrane traffic at the tip of elongating pollen tubes.
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Affiliation(s)
- Gleb Grebnev
- Cell Biology, Department of Biology, Friedrich-Alexander-University Erlangen Nuremberg, 91058 Erlangen, Germany
| | - Mislav Cvitkovic
- PULS Group, Department of Physics, Friedrich-Alexander-University Erlangen Nuremberg, 91058 Erlangen, Germany
- Group for Computational Life Sciences, Division of Physical Chemistry, Ruđer Bošković Institute, 10000 Zagreb, Croatia
| | - Carolin Fritz
- Cell Biology, Department of Biology, Friedrich-Alexander-University Erlangen Nuremberg, 91058 Erlangen, Germany
| | - Giampiero Cai
- Department of Life Sciences, University of Siena, 53100 Siena, Italy
| | - Ana-Suncana Smith
- PULS Group, Department of Physics, Friedrich-Alexander-University Erlangen Nuremberg, 91058 Erlangen, Germany
- Group for Computational Life Sciences, Division of Physical Chemistry, Ruđer Bošković Institute, 10000 Zagreb, Croatia
| | - Benedikt Kost
- Cell Biology, Department of Biology, Friedrich-Alexander-University Erlangen Nuremberg, 91058 Erlangen, Germany
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Anuar N, Sabri AH, Bustami Effendi TJ, Abdul Hamid K. Development and characterisation of ibuprofen-loaded nanoemulsion with enhanced oral bioavailability. Heliyon 2020; 6:e04570. [PMID: 32775730 PMCID: PMC7394867 DOI: 10.1016/j.heliyon.2020.e04570] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 07/14/2020] [Accepted: 07/23/2020] [Indexed: 02/06/2023] Open
Abstract
Lipophilic compounds constitute a majority of therapeutics in the pipeline of drug discovery. Despite possessing enhanced efficacy and permeability, some of these drugs suffer poor solubility necessitating the need of a suitable drug delivery system. Nanoemulsion is a drug delivery system that provides enhanced solubility for poorly soluble drugs in an attempt to improve the oral bioavailability. The purpose of this study is to develop a nanoemulsion system using ibuprofen as a model drug in order to investigate the potential of this colloidal system to enhance the absorption of poorly water-soluble drugs. Ibuprofen loaded-nanoemulsion with different drug concentrations (1.5, 3 and 6% w/w) were formulated from olive oil, sucrose ester L-1695 and glycerol using D-phase emulsification technique. A pseudoternary phase diagram was utilised to identify the optimal excipient composition to formulate the nanoemulsion system. In vitro diffusion chamber studies using rodent intestinal linings highlighted improved absorption profile when ibuprofen was delivered as nanoemulsion in comparison to microemulsions and drug-in-oil systems. This was further corroborated by in vivo studies using rat model that highlighted a two-fold increase in ibuprofen absorption when the drug was administered as a nanoemulsion relative to drug-in-oil system. On the other hand, when ibuprofen was administered as microemulsions, only a 1.5-fold increase in absorption was observed relative to drug-in-oil system. Thus, this study highlights the potential of using nanoemulsion as a drug delivery system to enhance the oral bioavailability of hydrophobic drugs.
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Affiliation(s)
- Nurfazreen Anuar
- Department of Pharmaceutics, Faculty of Pharmacy, Universiti Teknologi MARA, Cawangan Selangor, 42300 Puncak Alam, Selangor, Malaysia
| | - Akmal H. Sabri
- Advanced Materials and Healthcare Technologies Group, School of Pharmacy, The University of Nottingham, NG7 2RD, Nottingham, UK
| | - Tommy Julianto Bustami Effendi
- Department of Pharmaceutics, Faculty of Pharmacy, Universiti Teknologi MARA, Cawangan Selangor, 42300 Puncak Alam, Selangor, Malaysia
| | - Khuriah Abdul Hamid
- Department of Pharmaceutics, Faculty of Pharmacy, Universiti Teknologi MARA, Cawangan Selangor, 42300 Puncak Alam, Selangor, Malaysia
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Sansen T, Sanchez-Fuentes D, Rathar R, Colom-Diego A, El Alaoui F, Viaud J, Macchione M, de Rossi S, Matile S, Gaudin R, Bäcker V, Carretero-Genevrier A, Picas L. Mapping Cell Membrane Organization and Dynamics Using Soft Nanoimprint Lithography. ACS APPLIED MATERIALS & INTERFACES 2020; 12:29000-29012. [PMID: 32464046 DOI: 10.1021/acsami.0c05432] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Membrane shape is a key feature of many cellular processes, including cell differentiation, division, migration, and trafficking. The development of nanostructured surfaces allowing for the in situ manipulation of membranes in living cells is crucial to understand these processes, but this requires complicated and limited-access technologies. Here, we investigate the self-organization of cellular membranes by using a customizable and benchtop method allowing one to engineer 1D SiO2 nanopillar arrays of defined sizes and shapes on high-performance glass compatible with advanced microscopies. As a result of this original combination, we provide a mapping of the morphology-induced modulation of the cell membrane mechanics, dynamics and steady-state organization of key protein complexes implicated in cellular trafficking and signal transduction.
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Affiliation(s)
- T Sansen
- Institut de Recherche en Infectiologie de Montpellier (IRIM), CNRS UMR 9004-Université de Montpellier, 34293 Montpellier, France
| | - D Sanchez-Fuentes
- Institut d'Électronique et des Systèmes (IES), CNRS UMR 5214-Université de Montpellier, 34097 Montpellier, France
| | - R Rathar
- Institut de Recherche en Infectiologie de Montpellier (IRIM), CNRS UMR 9004-Université de Montpellier, 34293 Montpellier, France
- Institut d'Électronique et des Systèmes (IES), CNRS UMR 5214-Université de Montpellier, 34097 Montpellier, France
| | - A Colom-Diego
- Biochemistry Department and School of Chemistry and Biochemistry and Swiss National Centre for Competence in Research in Chemical Biology, University of Geneva, CH-1211 Geneva, Switzerland
| | - F El Alaoui
- Institut de Recherche en Infectiologie de Montpellier (IRIM), CNRS UMR 9004-Université de Montpellier, 34293 Montpellier, France
| | - J Viaud
- Institute of Cardiovascular and Metabolic Diseases (I2MC-UMR1048), Inserm and Université Toulouse 3, Avenue Jean Poulhès BP84225, 31432 Cedex 04 Toulouse, France
| | - M Macchione
- School of Chemistry and Biochemistry and Swiss National Centre for Competence in Research in Chemical Biology, University of Geneva, CH-1211 Geneva, Switzerland
| | - S de Rossi
- MRI Imaging Facility, UMS BioCampus Montpellier, 34000 Montpellier, France
| | - S Matile
- School of Chemistry and Biochemistry and Swiss National Centre for Competence in Research in Chemical Biology, University of Geneva, CH-1211 Geneva, Switzerland
| | - R Gaudin
- Institut de Recherche en Infectiologie de Montpellier (IRIM), CNRS UMR 9004-Université de Montpellier, 34293 Montpellier, France
| | - V Bäcker
- MRI Imaging Facility, UMS BioCampus Montpellier, 34000 Montpellier, France
| | - A Carretero-Genevrier
- Institut d'Électronique et des Systèmes (IES), CNRS UMR 5214-Université de Montpellier, 34097 Montpellier, France
| | - L Picas
- Institut de Recherche en Infectiologie de Montpellier (IRIM), CNRS UMR 9004-Université de Montpellier, 34293 Montpellier, France
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Accumulation of Neurofascin at Nodes of Ranvier Is Regulated by a Paranodal Switch. J Neurosci 2020; 40:5709-5723. [PMID: 32554548 DOI: 10.1523/jneurosci.0830-19.2020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 04/29/2020] [Accepted: 06/02/2020] [Indexed: 12/18/2022] Open
Abstract
The paranodal junctions flank mature nodes of Ranvier and provide a barrier between ion channels at the nodes and juxtaparanodes. These junctions also promote node assembly and maintenance by mechanisms that are poorly understood. Here, we examine their role in the accumulation of NF186, a key adhesion molecule of PNS and CNS nodes. We previously showed that NF186 is initially targeted/accumulates via its ectodomain to forming PNS (hemi)nodes by diffusion trapping, whereas it is later targeted to mature nodes by a transport-dependent mechanism mediated by its cytoplasmic segment. To address the role of the paranodes in this switch, we compared accumulation of NF186 ectodomain and cytoplasmic domain constructs in WT versus paranode defective (i.e., Caspr-null) mice. Both pathways are affected in the paranodal mutants. In the PNS of Caspr-null mice, diffusion trapping mediated by the NF186 ectodomain aberrantly persists into adulthood, whereas the cytoplasmic domain/transport-dependent targeting is impaired. In contrast, accumulation of NF186 at CNS nodes does not undergo a switch; it is predominantly targeted to both forming and mature CNS nodes via its cytoplasmic domain and requires intact paranodes. Fluorescence recovery after photobleaching analysis indicates that the paranodes provide a membrane diffusion barrier that normally precludes diffusion of NF186 to nodes. Linkage of paranodal proteins to the underlying cytoskeleton likely contributes to this diffusion barrier based on 4.1B and βII spectrin expression in Caspr-null mice. Together, these results implicate the paranodes as membrane diffusion barriers that regulate targeting to nodes and highlight differences in the assembly of PNS and CNS nodes.SIGNIFICANCE STATEMENT Nodes of Ranvier are essential for effective saltatory conduction along myelinated axons. A major question is how the various axonal proteins that comprise the multimeric nodal complex accumulate at this site. Here we examine how targeting of NF186, a key nodal adhesion molecule, is regulated by the flanking paranodal junctions. We show that the transition from diffusion-trapping to transport-dependent accumulation of NF186 requires the paranodal junctions. We also demonstrate that these junctions are a barrier to diffusion of axonal proteins into the node and highlight differences in PNS and CNS node assembly. These results provide new insights into the mechanism of node assembly and the pathophysiology of neurologic disorders in which impaired paranodal function contributes to clinical disability.
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Bahmanyar S, Schlieker C. Lipid and protein dynamics that shape nuclear envelope identity. Mol Biol Cell 2020; 31:1315-1323. [PMID: 32530796 PMCID: PMC7353140 DOI: 10.1091/mbc.e18-10-0636] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 04/13/2020] [Accepted: 04/17/2020] [Indexed: 12/17/2022] Open
Abstract
The nuclear envelope (NE) is continuous with the endoplasmic reticulum (ER), yet the NE carries out many functions distinct from those of bulk ER. This functional specialization depends on a unique protein composition that defines NE identity and must be both established and actively maintained. The NE undergoes extensive remodeling in interphase and mitosis, so mechanisms that seal NE holes and protect its unique composition are critical for maintaining its functions. New evidence shows that closure of NE holes relies on regulated de novo lipid synthesis, providing a link between lipid metabolism and generating and maintaining NE identity. Here, we review regulation of the lipid bilayers of the NE and suggest ways to generate lipid asymmetry across the NE despite its direct continuity with the ER. We also discuss the elusive mechanism of membrane fusion during nuclear pore complex (NPC) biogenesis. We propose a model in which NPC biogenesis is carefully controlled to ensure that a permeability barrier has been established before membrane fusion, thereby avoiding a major threat to compartmentalization.
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Affiliation(s)
- Shirin Bahmanyar
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06520
| | - Christian Schlieker
- Department of Molecular Biophysics & Biochemistry, Yale University, New Haven, CT 06520
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520
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43
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Garcia E, Ismail S. Spatiotemporal Regulation of Signaling: Focus on T Cell Activation and the Immunological Synapse. Int J Mol Sci 2020; 21:E3283. [PMID: 32384769 PMCID: PMC7247333 DOI: 10.3390/ijms21093283] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/01/2020] [Accepted: 05/03/2020] [Indexed: 01/22/2023] Open
Abstract
In a signaling network, not only the functions of molecules are important but when (temporal) and where (spatial) those functions are exerted and orchestrated is what defines the signaling output. To temporally and spatially modulate signaling events, cells generate specialized functional domains with variable lifetime and size that concentrate signaling molecules, enhancing their transduction potential. The plasma membrane is a key in this regulation, as it constitutes a primary signaling hub that integrates signals within and across the membrane. Here, we examine some of the mechanisms that cells exhibit to spatiotemporally regulate signal transduction, focusing on the early events of T cell activation from triggering of T cell receptor to formation and maturation of the immunological synapse.
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Affiliation(s)
- Esther Garcia
- CR-UK Beatson Institute, Garscube Estate, Switchback Road, Glasgow G61 1BD, UK
| | - Shehab Ismail
- CR-UK Beatson Institute, Garscube Estate, Switchback Road, Glasgow G61 1BD, UK
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Syga Ł, de Vries RH, van Oosterhout H, Bartelds R, Boersma AJ, Roelfes G, Poolman B. A Trifunctional Linker for Palmitoylation and Peptide and Protein Localization in Biological Membranes. Chembiochem 2020; 21:1320-1328. [PMID: 31814256 PMCID: PMC7317724 DOI: 10.1002/cbic.201900655] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Indexed: 01/09/2023]
Abstract
Attachment of lipophilic groups is an important post-translational modification of proteins, which involves the coupling of one or more anchors such as fatty acids, isoprenoids, phospholipids, or glycosylphosphatidyl inositols. To study its impact on the membrane partitioning of hydrophobic peptides or proteins, we designed a tyrosine-based trifunctional linker. The linker allows the facile incorporation of two different functionalities at a cysteine residue in a single step. We determined the effect of the lipid modification on the membrane partitioning of the synthetic α-helical model peptide WALP with or without here and in all cases below; palmitoyl groups in giant unilamellar vesicles that contain a liquid-ordered (Lo ) and liquid-disordered (Ld ) phase. Introduction of two palmitoyl groups did not alter the localization of the membrane peptides, nor did the membrane thickness or lipid composition. In all cases, the peptide was retained in the Ld phase. These data demonstrate that the Lo domain in model membranes is highly unfavorable for a single membrane-spanning peptide.
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Affiliation(s)
- Łukasz Syga
- Department of BiochemistryGroningen Biomolecular Sciences andBiotechnology Institute and Zernike Institute for Advanced MaterialsUniversity of GroningenNijenborgh 49747 AGGroningenThe Netherlands
| | - Reinder H. de Vries
- Department of Biomolecular Chemistry and CatalysisStratingh Institute for ChemistryUniversity of GroningenNijenborgh 49747 AGGroningenThe Netherlands
| | - Hugo van Oosterhout
- Department of Biomolecular Chemistry and CatalysisStratingh Institute for ChemistryUniversity of GroningenNijenborgh 49747 AGGroningenThe Netherlands
| | - Rianne Bartelds
- Department of BiochemistryGroningen Biomolecular Sciences andBiotechnology Institute and Zernike Institute for Advanced MaterialsUniversity of GroningenNijenborgh 49747 AGGroningenThe Netherlands
| | - Arnold J. Boersma
- DWI Leibniz Institute for Interactive MaterialsForckenbeckstrasse 5052074AachenGermany
| | - Gerard Roelfes
- Department of Biomolecular Chemistry and CatalysisStratingh Institute for ChemistryUniversity of GroningenNijenborgh 49747 AGGroningenThe Netherlands
| | - Bert Poolman
- Department of BiochemistryGroningen Biomolecular Sciences andBiotechnology Institute and Zernike Institute for Advanced MaterialsUniversity of GroningenNijenborgh 49747 AGGroningenThe Netherlands
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45
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Establishing and regulating the composition of cilia for signal transduction. Nat Rev Mol Cell Biol 2020; 20:389-405. [PMID: 30948801 DOI: 10.1038/s41580-019-0116-4] [Citation(s) in RCA: 244] [Impact Index Per Article: 61.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The primary cilium is a hair-like surface-exposed organelle of the eukaryotic cell that decodes a variety of signals - such as odorants, light and Hedgehog morphogens - by altering the local concentrations and activities of signalling proteins. Signalling within the cilium is conveyed through a diverse array of second messengers, including conventional signalling molecules (such as cAMP) and some unusual intermediates (such as sterols). Diffusion barriers at the ciliary base establish the unique composition of this signalling compartment, and cilia adapt their proteome to signalling demands through regulated protein trafficking. Much progress has been made on the molecular understanding of regulated ciliary trafficking, which encompasses not only exchanges between the cilium and the rest of the cell but also the shedding of signalling factors into extracellular vesicles.
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46
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Kadam K, Khole VV, Ghosalkar K, Jagtap D, Yarramala DS, Ramachandran B. Thiol based mechanism internalises interacting partners to outer dense fibers in sperm. Free Radic Biol Med 2020; 148:170-181. [PMID: 31923584 DOI: 10.1016/j.freeradbiomed.2019.12.031] [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: 09/30/2019] [Revised: 12/04/2019] [Accepted: 12/23/2019] [Indexed: 11/19/2022]
Abstract
The sperm tail outer dense fibres (ODFs) contribute passive structural role in sperm motility. The level of disulphide cross-linking of ODFs and their structural thickness determines flagellar bending curvature and motility. During epididymal maturation, proteins are internalized to modify ODF disulphide cross-linking and enable motility. Sperm thiol status is further altered during capacitation in female tract. This suggests that components in female reproductive tract acting on thiol/disulphides could be capable of modulating the tail stiffness to facilitate modulation of the sperm tail rigidity and waveform en route to fertilization. Understanding the biochemical properties and client proteins of ODFs in reproductive tract fluids will help bridge this gap. Using recombinant ODF2 (aka Testis Specific Antigen of 70 kDa) as bait, we identified client proteins in male and female reproductive fluids. A thiol-based interaction and internalization indicates sperm can harness reproductive tract fluids for proteins that interact with ODFs and likely modulate the tail stiffness en route to fertilization.
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Affiliation(s)
- Kaushiki Kadam
- Department of Gamete Immunobiology, National Institute for Research in Reproductive Health, J.M Street, Parel, Mumbai, 400012, India.
| | - Vrinda V Khole
- Department of Gamete Immunobiology, National Institute for Research in Reproductive Health, J.M Street, Parel, Mumbai, 400012, India
| | - Kanaka Ghosalkar
- Department of Gamete Immunobiology, National Institute for Research in Reproductive Health, J.M Street, Parel, Mumbai, 400012, India
| | - Dhanashree Jagtap
- Structural Biology Department, National Institute for Research in Reproductive Health, J.M Street, Parel, Mumbai, 400012, India
| | - Deepthi S Yarramala
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400 076, India
| | - Bini Ramachandran
- Thermo Fisher Scientific India Pvt. Ltd, 403-404, Delphi 'B' Wing, Hiranandani Business Park, Powai, Mumbai, 400076, India
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Carlton JG, Jones H, Eggert US. Membrane and organelle dynamics during cell division. Nat Rev Mol Cell Biol 2020; 21:151-166. [DOI: 10.1038/s41580-019-0208-1] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/20/2019] [Indexed: 12/31/2022]
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48
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Reinhardt R, Truebestein L, Schmidt HA, Leonard TA. It Takes Two to Tango: Activation of Protein Kinase D by Dimerization. Bioessays 2020; 42:e1900222. [PMID: 31997382 DOI: 10.1002/bies.201900222] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 01/10/2020] [Indexed: 12/23/2022]
Abstract
The recent discovery and structure determination of a novel ubiquitin-like dimerization domain in protein kinase D (PKD) has significant implications for its activation. PKD is a serine/threonine kinase activated by the lipid second messenger diacylglycerol (DAG). It is an essential and highly conserved protein that is implicated in plasma membrane directed trafficking processes from the trans-Golgi network. However, many open questions surround its mechanism of activation, its localization, and its role in the biogenesis of cargo transport carriers. In reviewing this field, the focus is primarily on the mechanisms that control the activation of PKD at precise locations in the cell. In light of the new structural findings, the understanding of the mechanisms underlying PKD activation is critically evaluated, with particular emphasis on the role of dimerization in PKD autophosphorylation, and the provenance and recognition of the DAG that activates PKD.
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Affiliation(s)
- Ronja Reinhardt
- Department of Structural and Computational Biology, Max Perutz Labs, Vienna Biocenter, 1030, Vienna, Austria.,Department of Medical Biochemistry, Medical University of Vienna, 1030, Vienna, Austria
| | - Linda Truebestein
- Department of Structural and Computational Biology, Max Perutz Labs, Vienna Biocenter, 1030, Vienna, Austria.,Department of Medical Biochemistry, Medical University of Vienna, 1030, Vienna, Austria
| | - Heiko A Schmidt
- Center for Integrative Bioinformatics Vienna, Max Perutz Labs, University of Vienna and Medical University of Vienna, Vienna Biocenter, 1030, Vienna, Austria
| | - Thomas A Leonard
- Department of Structural and Computational Biology, Max Perutz Labs, Vienna Biocenter, 1030, Vienna, Austria.,Department of Medical Biochemistry, Medical University of Vienna, 1030, Vienna, Austria
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Cataloguing and Selection of mRNAs Localized to Dendrites in Neurons and Regulated by RNA-Binding Proteins in RNA Granules. Biomolecules 2020; 10:biom10020167. [PMID: 31978946 PMCID: PMC7072219 DOI: 10.3390/biom10020167] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 01/18/2020] [Accepted: 01/20/2020] [Indexed: 12/15/2022] Open
Abstract
Spatiotemporal translational regulation plays a key role in determining cell fate and function. Specifically, in neurons, local translation in dendrites is essential for synaptic plasticity and long-term memory formation. To achieve local translation, RNA-binding proteins in RNA granules regulate target mRNA stability, localization, and translation. To date, mRNAs localized to dendrites have been identified by comprehensive analyses. In addition, mRNAs associated with and regulated by RNA-binding proteins have been identified using various methods in many studies. However, the results obtained from these numerous studies have not been compiled together. In this review, we have catalogued mRNAs that are localized to dendrites and are associated with and regulated by the RNA-binding proteins fragile X mental retardation protein (FMRP), RNA granule protein 105 (RNG105, also known as Caprin1), Ras-GAP SH3 domain binding protein (G3BP), cytoplasmic polyadenylation element binding protein 1 (CPEB1), and staufen double-stranded RNA binding proteins 1 and 2 (Stau1 and Stau2) in RNA granules. This review provides comprehensive information on dendritic mRNAs, the neuronal functions of mRNA-encoded proteins, the association of dendritic mRNAs with RNA-binding proteins in RNA granules, and the effects of RNA-binding proteins on mRNA regulation. These findings provide insights into the mechanistic basis of protein-synthesis-dependent synaptic plasticity and memory formation and contribute to future efforts to understand the physiological implications of local regulation of dendritic mRNAs in neurons.
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50
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Abstract
Macropinosome formation occurs as a localized sequence of biochemical activities and associated morphological changes, which may be considered a form of signal transduction leading to the construction of an organelle. Macropinocytosis may also convey information about the availability of extracellular nutrients to intracellular regulators of metabolism. Consistent with this idea, activation of the metabolic regulator mechanistic target of rapamycin complex-1 (mTORC1) in response to acute stimulation by growth factors and extracellular amino acids requires internalization of amino acids by macropinocytosis. This suggests that macropinocytosis is necessary for mTORC1-dependent growth of metazoan cells, both as a route for delivery of amino acids to sensors associated with lysosomes and as a platform for growth factor-dependent signalling to mTORC1 via phosphatidylinositol 3-kinase (PI3K) and the Akt pathway. Because the biochemical signals required for the construction of macropinosomes are also required for cell growth, and inhibition of macropinocytosis inhibits growth factor signalling to mTORC1, we propose that signalling by growth factor receptors is organized into stochastic, structure-dependent cascades of chemical reactions that both build a macropinosome and stimulate mTORC1. More generally, as discrete units of signal transduction, macropinosomes may be subject to feedback regulation by metabolism and cell dimensions. This article is part of the Theo Murphy meeting issue 'Macropinocytosis'.
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Affiliation(s)
- Joel A Swanson
- Department of Microbiology and Immunology, University of Michigan Medical School , Ann Arbor, MI 48109-5620 , USA
| | - Sei Yoshida
- Department of Microbiology and Immunology, University of Michigan Medical School , Ann Arbor, MI 48109-5620 , USA
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