1
|
Kourkoulou A, Martzoukou O, Fischer R, Amillis S. A type II phosphatidylinositol-4-kinase coordinates sorting of cargo polarizing by endocytic recycling. Commun Biol 2024; 7:855. [PMID: 38997419 PMCID: PMC11245547 DOI: 10.1038/s42003-024-06553-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 07/04/2024] [Indexed: 07/14/2024] Open
Abstract
Depending on their phosphorylation status, derivatives of phosphatidylinositol play important roles in vesicle identity, recognition and intracellular trafficking processes. In eukaryotic cells, phosphatidylinositol-4 phosphate pools generated by specific kinases are key determinants of the conventional secretion pathways. Earlier work in yeast has classified phosphatidylinositol-4 kinases in two types, Stt4p and Pik1p belonging to type III and Lsb6p to type II, with distinct cellular localizations and functions. Eurotiomycetes appear to lack Pik1p homologues. In Aspergillus nidulans, unlike homologues in other fungi, AnLsb6 is associated to late Golgi membranes and when heterologously overexpressed, it compensates for the thermosensitive phenotype in a Saccharomyces cerevisiae pik1 mutant, whereas its depletion leads to disorganization of Golgi-associated PHOSBP-labelled membranes, that tend to aggregate dependent on functional Rab5 GTPases. Evidence provided herein, indicates that the single type II phosphatidylinositol-4 kinase AnLsb6 is the main contributor for decorating secretory vesicles with relevant phosphatidylinositol-phosphate species, which navigate essential cargoes following the route of apical polarization via endocytic recycling.
Collapse
Affiliation(s)
- Anezia Kourkoulou
- National and Kapodistrian University of Athens, Department of Biology, Athens, Hellas, Greece
| | - Olga Martzoukou
- National and Kapodistrian University of Athens, Department of Biology, Athens, Hellas, Greece
| | - Reinhard Fischer
- Karlsruhe Institute of Technology - South Campus, Institute for Applied Biosciences, Department of Microbiology, Karlsruhe, Germany
| | - Sotiris Amillis
- National and Kapodistrian University of Athens, Department of Biology, Athens, Hellas, Greece.
- Karlsruhe Institute of Technology - South Campus, Institute for Applied Biosciences, Department of Microbiology, Karlsruhe, Germany.
| |
Collapse
|
2
|
Mansat M, Kpotor AO, Chicanne G, Picot M, Mazars A, Flores-Flores R, Payrastre B, Hnia K, Viaud J. MTM1-mediated production of phosphatidylinositol 5-phosphate fuels the formation of podosome-like protrusions regulating myoblast fusion. Proc Natl Acad Sci U S A 2024; 121:e2217971121. [PMID: 38805272 PMCID: PMC11161799 DOI: 10.1073/pnas.2217971121] [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: 10/21/2022] [Accepted: 04/10/2024] [Indexed: 05/30/2024] Open
Abstract
Myogenesis is a multistep process that requires a spatiotemporal regulation of cell events resulting finally in myoblast fusion into multinucleated myotubes. Most major insights into the mechanisms underlying fusion seem to be conserved from insects to mammals and include the formation of podosome-like protrusions (PLPs) that exert a driving force toward the founder cell. However, the machinery that governs this process remains poorly understood. In this study, we demonstrate that MTM1 is the main enzyme responsible for the production of phosphatidylinositol 5-phosphate, which in turn fuels PI5P 4-kinase α to produce a minor and functional pool of phosphatidylinositol 4,5-bisphosphate that concentrates in PLPs containing the scaffolding protein Tks5, Dynamin-2, and the fusogenic protein Myomaker. Collectively, our data reveal a functional crosstalk between a PI-phosphatase and a PI-kinase in the regulation of PLP formation.
Collapse
Affiliation(s)
- Mélanie Mansat
- INSERM UMR1297, University of Toulouse 3, Institute of Metabolic and Cardiovascular Diseases (I2MC)31432, Toulouse Cedex 04, France
| | - Afi Oportune Kpotor
- INSERM UMR1297, University of Toulouse 3, Institute of Metabolic and Cardiovascular Diseases (I2MC)31432, Toulouse Cedex 04, France
| | - Gaëtan Chicanne
- INSERM UMR1297, University of Toulouse 3, Institute of Metabolic and Cardiovascular Diseases (I2MC)31432, Toulouse Cedex 04, France
| | - Mélanie Picot
- INSERM UMR1297, University of Toulouse 3, Institute of Metabolic and Cardiovascular Diseases (I2MC)31432, Toulouse Cedex 04, France
| | - Anne Mazars
- INSERM UMR1297, University of Toulouse 3, Institute of Metabolic and Cardiovascular Diseases (I2MC)31432, Toulouse Cedex 04, France
| | - Rémy Flores-Flores
- INSERM UMR1297, University of Toulouse 3, Institute of Metabolic and Cardiovascular Diseases (I2MC)31432, Toulouse Cedex 04, France
| | - Bernard Payrastre
- INSERM UMR1297, University of Toulouse 3, Institute of Metabolic and Cardiovascular Diseases (I2MC)31432, Toulouse Cedex 04, France
- Hematology Laboratory, University Hospital of Toulouse31059, Toulouse Cedex 03, France
| | - Karim Hnia
- INSERM UMR1297, University of Toulouse 3, Institute of Metabolic and Cardiovascular Diseases (I2MC)31432, Toulouse Cedex 04, France
| | - Julien Viaud
- INSERM UMR1297, University of Toulouse 3, Institute of Metabolic and Cardiovascular Diseases (I2MC)31432, Toulouse Cedex 04, France
| |
Collapse
|
3
|
Hämälistö S, Del Valle Batalla F, Yuseff MI, Mattila PK. Endolysosomal vesicles at the center of B cell activation. J Cell Biol 2024; 223:e202307047. [PMID: 38305771 PMCID: PMC10837082 DOI: 10.1083/jcb.202307047] [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: 07/14/2023] [Revised: 12/22/2023] [Accepted: 01/17/2024] [Indexed: 02/03/2024] Open
Abstract
The endolysosomal system specializes in degrading cellular components and is crucial to maintaining homeostasis and adapting rapidly to metabolic and environmental cues. Cells of the immune system exploit this network to process antigens or promote cell death by secreting lysosome-related vesicles. In B lymphocytes, lysosomes are harnessed to facilitate the extraction of antigens and to promote their processing into peptides for presentation to T cells, critical steps to mount protective high-affinity antibody responses. Intriguingly, lysosomal vesicles are now considered important signaling units within cells and also display secretory functions by releasing their content to the extracellular space. In this review, we focus on how B cells use pathways involved in the intracellular trafficking, secretion, and function of endolysosomes to promote adaptive immune responses. A basic understanding of such mechanisms poses an interesting frontier for the development of therapeutic strategies in the context of cancer and autoimmune diseases.
Collapse
Affiliation(s)
- Saara Hämälistö
- Institute of Biomedicine, and MediCity Research Laboratories, University of Turku, Turku, Finland
- Turku Bioscience, University of Turku and Åbo Akademi University, Turku, Finland
- InFLAMES Research Flagship, University of Turku, Turku, Finland
- Cancer Research Unit and FICAN West Cancer Centre Laboratory, Turku, Finland
| | - Felipe Del Valle Batalla
- Laboratory of Immune Cell Biology, Department of Cellular and Molecular Biology, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - María Isabel Yuseff
- Laboratory of Immune Cell Biology, Department of Cellular and Molecular Biology, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Pieta K. Mattila
- Institute of Biomedicine, and MediCity Research Laboratories, University of Turku, Turku, Finland
- Turku Bioscience, University of Turku and Åbo Akademi University, Turku, Finland
- InFLAMES Research Flagship, University of Turku, Turku, Finland
| |
Collapse
|
4
|
Sharma M, Mukherjee S, Shaw AK, Mondal A, Behera A, Das J, Bose A, Sinha B, Sarma JD. Connexin 43 mediated collective cell migration is independent of Golgi orientation. Biol Open 2023; 12:bio060006. [PMID: 37815438 PMCID: PMC10629497 DOI: 10.1242/bio.060006] [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: 05/15/2023] [Accepted: 09/28/2023] [Indexed: 10/11/2023] Open
Abstract
Cell migration is vital for multiple physiological functions and is involved in the metastatic dissemination of tumour cells in various cancers. For effective directional migration, cells often reorient their Golgi apparatus and, therefore, the secretory traffic towards the leading edge. However, not much is understood about the regulation of Golgi's reorientation. Herein, we address the role of gap junction protein Connexin 43 (Cx43), which connects cells, allowing the direct exchange of molecules. We utilized HeLa WT cells lacking Cx43 and HeLa 43 cells, stably expressing Cx43, and found that functional Cx43 channels affected Golgi morphology and reduced the reorientation of Golgi during cell migration. Although the migration velocity of the front was reduced in HeLa 43, the front displayed enhanced coherence in movement, implying an augmented collective nature of migration. On BFA treatment, Golgi was dispersed and the high heterogeneity in inter-regional front velocity of HeLa WT cells was reduced to resemble the HeLa 43. HeLa 43 had higher vimentin expression and stronger basal F-actin. Furthermore, non-invasive measurement of basal membrane height fluctuations revealed a lower membrane tension. We, therefore, propose that reorientation of Golgi is not the major determinant of migration in the presence of Cx43, which induces collective-like coherent migration in cells.
Collapse
Affiliation(s)
- Madhav Sharma
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia 741246, India
| | - Suvam Mukherjee
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia 741246, India
| | - Archana Kumari Shaw
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia 741246, India
| | - Anushka Mondal
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia 741246, India
| | - Amrutamaya Behera
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia 741246, India
| | - Jibitesh Das
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia 741246, India
| | - Abhishek Bose
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia 741246, India
| | - Bidisha Sinha
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia 741246, India
| | - Jayasri Das Sarma
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia 741246, India
| |
Collapse
|
5
|
Heckle LA, Kozminski KG. Osh-dependent and -independent Regulation of PI4P Levels During Polarized Growth of Saccharomyces cerevisiae. Mol Biol Cell 2023; 34:ar104. [PMID: 37556206 PMCID: PMC10559303 DOI: 10.1091/mbc.e23-03-0089] [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: 03/10/2023] [Revised: 07/03/2023] [Accepted: 07/31/2023] [Indexed: 08/11/2023] Open
Abstract
Polarized secretion facilitates polarized cell growth. For a secretory vesicle to dock at the plasma membrane, it must mature with a progressive association or dissociation of molecules that are, respectively, necessary for or inhibitory to vesicle docking, including an exchange of Rab GTPases. In current models, oxysterol-binding protein homologue 4 (Osh4p) establishes a phosphatidylinositol 4-phosphate (PI4P) gradient along the secretory trafficking pathway such that vesicles have higher PI4P levels after budding from the trans-Golgi relative to when vesicles arrive at the plasma membrane. In this study, using the lipid-binding domain P4M and live-cell imaging, we show that secretory vesicle-associated PI4P levels remain constant when vesicles traffic from the trans-Golgi to the plasma membrane. We also show that deletion of OSH4 does not alter vesicle-associated PI4P levels, though loss of any individual member of the OSH family or complete loss of OSH family function alters the intracellular distribution of PI4P. We propose a model in which the Rab GTPases Ypt32p and Sec4p remain associated with a secretory vesicle during trafficking, independent of PI4P levels and Osh4p. Together these data indicate the necessity of experiments revealing the location and timing of events required for vesicle maturation.
Collapse
Affiliation(s)
- Lindsay A. Heckle
- Department of Biology, University of Virginia, Charlottesville, VA 22904
| | - Keith G. Kozminski
- Department of Biology, University of Virginia, Charlottesville, VA 22904
- Department of Cell Biology, University of Virginia, Charlottesville, VA 22908
| |
Collapse
|
6
|
Hamilton MC, Fife JD, Akinci E, Yu T, Khowpinitchai B, Cha M, Barkal S, Thi TT, Yeo GH, Ramos Barroso JP, Francoeur MJ, Velimirovic M, Gifford DK, Lettre G, Yu H, Cassa CA, Sherwood RI. Systematic elucidation of genetic mechanisms underlying cholesterol uptake. CELL GENOMICS 2023; 3:100304. [PMID: 37228746 PMCID: PMC10203276 DOI: 10.1016/j.xgen.2023.100304] [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: 06/27/2022] [Revised: 12/02/2022] [Accepted: 03/24/2023] [Indexed: 05/27/2023]
Abstract
Genetic variation contributes greatly to LDL cholesterol (LDL-C) levels and coronary artery disease risk. By combining analysis of rare coding variants from the UK Biobank and genome-scale CRISPR-Cas9 knockout and activation screening, we substantially improve the identification of genes whose disruption alters serum LDL-C levels. We identify 21 genes in which rare coding variants significantly alter LDL-C levels at least partially through altered LDL-C uptake. We use co-essentiality-based gene module analysis to show that dysfunction of the RAB10 vesicle transport pathway leads to hypercholesterolemia in humans and mice by impairing surface LDL receptor levels. Further, we demonstrate that loss of function of OTX2 leads to robust reduction in serum LDL-C levels in mice and humans by increasing cellular LDL-C uptake. Altogether, we present an integrated approach that improves our understanding of the genetic regulators of LDL-C levels and provides a roadmap for further efforts to dissect complex human disease genetics.
Collapse
Affiliation(s)
- Marisa C. Hamilton
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - James D. Fife
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Ersin Akinci
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Tian Yu
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Benyapa Khowpinitchai
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Minsun Cha
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Sammy Barkal
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Thi Tun Thi
- Precision Medicine Research Programme, Cardiovascular Disease Research Programme, and Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Grace H.T. Yeo
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Department of Biological Engineering, Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Juan Pablo Ramos Barroso
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Matthew Jake Francoeur
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Minja Velimirovic
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - David K. Gifford
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Department of Biological Engineering, Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Guillaume Lettre
- Montreal Heart Institute, Montréal, QC H1T 1C8, Canada
- Faculté de Médecine, Université de Montréal, Montréal, QC H3T 1J4, Canada
| | - Haojie Yu
- Precision Medicine Research Programme, Cardiovascular Disease Research Programme, and Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Christopher A. Cassa
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Richard I. Sherwood
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| |
Collapse
|
7
|
Ireton K, Gyanwali GC, Herath TUB, Lee N. Exploitation of the host exocyst complex by bacterial pathogens. Mol Microbiol 2023. [PMID: 36717381 DOI: 10.1111/mmi.15034] [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: 11/17/2022] [Revised: 01/24/2023] [Accepted: 01/26/2023] [Indexed: 02/01/2023]
Abstract
Intracellular bacterial pathogens remodel the plasma membrane of eukaryotic cells in order to establish infection. A common and well-studied mechanism of plasma membrane remodelling involves bacterial stimulation of polymerization of the host actin cytoskeleton. Here, we discuss recent results showing that several bacterial pathogens also exploit the host vesicular trafficking pathway of 'polarized exocytosis' to expand and reshape specific regions in the plasma membrane during infection. Polarized exocytosis is mediated by an evolutionarily conserved octameric protein complex termed the exocyst. We describe examples in which the bacteria Listeria monocytogenes, Salmonella enterica serovar Typhimurium, and Shigella flexneri co-opt the exocyst to promote internalization into human cells or intercellular spread within host tissues. We also discuss results showing that Legionella pneumophila or S. flexneri manipulate exocyst components to modify membrane vacuoles to favour intracellular replication or motility of bacteria. Finally, we propose potential ways that pathogens manipulate exocyst function, discuss how polarized exocytosis might promote infection and highlight the importance of future studies to determine how actin polymerization and polarized exocytosis are coordinated to achieve optimal bacterial infection.
Collapse
Affiliation(s)
- Keith Ireton
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| | | | - Thilina U B Herath
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| | - Nicole Lee
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| |
Collapse
|
8
|
Hamilton MC, Fife JD, Akinci E, Yu T, Khowpinitchai B, Cha M, Barkal S, Thi TT, Yeo GH, Ramos Barroso JP, Jake Francoeur M, Velimirovic M, Gifford DK, Lettre G, Yu H, Cassa CA, Sherwood RI. Systematic elucidation of genetic mechanisms underlying cholesterol uptake. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.09.500804. [PMID: 36711952 PMCID: PMC9881906 DOI: 10.1101/2023.01.09.500804] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Genetic variation contributes greatly to LDL cholesterol (LDL-C) levels and coronary artery disease risk. By combining analysis of rare coding variants from the UK Biobank and genome-scale CRISPR-Cas9 knockout and activation screening, we have substantially improved the identification of genes whose disruption alters serum LDL-C levels. We identify 21 genes in which rare coding variants significantly alter LDL-C levels at least partially through altered LDL-C uptake. We use co-essentiality-based gene module analysis to show that dysfunction of the RAB10 vesicle transport pathway leads to hypercholesterolemia in humans and mice by impairing surface LDL receptor levels. Further, we demonstrate that loss of function of OTX2 leads to robust reduction in serum LDL-C levels in mice and humans by increasing cellular LDL-C uptake. Altogether, we present an integrated approach that improves our understanding of genetic regulators of LDL-C levels and provides a roadmap for further efforts to dissect complex human disease genetics.
Collapse
Affiliation(s)
- Marisa C. Hamilton
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - James D. Fife
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Ersin Akinci
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Tian Yu
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Benyapa Khowpinitchai
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Minsun Cha
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Sammy Barkal
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Thi Tun Thi
- Precision Medicine Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Cardiovascular Disease Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Grace H.T. Yeo
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Juan Pablo Ramos Barroso
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Matthew Jake Francoeur
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Minja Velimirovic
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - David K. Gifford
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Department of Biological Engineering, Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Guillaume Lettre
- Montreal Heart Institute, Montréal, Québec, H1T 1C8, Canada
- Faculté de Médecine, Université de Montréal, Montréal, Québec, H3T 1J4, Canada
| | - Haojie Yu
- Precision Medicine Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Cardiovascular Disease Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Christopher A. Cassa
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Richard I. Sherwood
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| |
Collapse
|
9
|
Listeria monocytogenes Co-Opts the Host Exocyst Complex To Promote Internalin A-Mediated Entry. Infect Immun 2022; 90:e0032622. [PMID: 36255255 PMCID: PMC9753705 DOI: 10.1128/iai.00326-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The bacterial pathogen Listeria monocytogenes induces its internalization (entry) into intestinal epithelial cells through interaction of its surface protein, internalin A (InlA), with the human cell-cell adhesion molecule, E-cadherin. While InlA-mediated entry requires bacterial stimulation of actin polymerization, it remains unknown whether additional host processes are manipulated to promote internalization. Here, we show that interaction of InlA with E-cadherin induces the host membrane-trafficking process of polarized exocytosis, which augments uptake of Listeria. Imaging studies revealed that exocytosis is stimulated at sites of InlA-dependent internalization. Experiments inhibiting human N-ethylmaleimide-sensitive factor (NSF) demonstrated that exocytosis is needed for efficient InlA-mediated entry. Polarized exocytosis is mediated by the exocyst complex, which comprises eight proteins, including Sec6, Exo70, and Exo84. We found that Exo70 was recruited to sites of InlA-mediated entry. In addition, depletion of Exo70, Exo84, or Sec6 by RNA interference impaired entry without affecting surface levels of E-cadherin. Similar to binding of InlA to E-cadherin, homophilic interaction of E-cadherin molecules mobilized the exocyst and stimulated exocytosis. Collectively, these results demonstrate that ligation of E-cadherin induces exocytosis that promotes Listeria entry, and they raise the possibility that the exocyst might also control the normal function of E-cadherin in cell-cell adhesion.
Collapse
|
10
|
Watanabe C, Shibuya H, Ichiyama Y, Okamura E, Tsukiyama-Fujii S, Tsukiyama T, Matsumoto S, Matsushita J, Azami T, Kubota Y, Ohji M, Sugiyama F, Takahashi S, Mizuno S, Tamura M, Mizutani KI, Ema M. Essential Roles of Exocyst Complex Component 3-like 2 on Cardiovascular Development in Mice. Life (Basel) 2022; 12:life12111730. [PMID: 36362885 PMCID: PMC9694714 DOI: 10.3390/life12111730] [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: 09/15/2022] [Revised: 10/20/2022] [Accepted: 10/25/2022] [Indexed: 12/01/2022] Open
Abstract
Angiogenesis is a process to generate new blood vessels from pre-existing vessels and to maintain vessels, and plays critical roles in normal development and disease. However, the molecular mechanisms underlying angiogenesis are not fully understood. This study examined the roles of exocyst complex component (Exoc) 3-like 2 (Exoc3l2) during development in mice. We found that Exoc3l1, Exoc3l2, Exoc3l3 and Exoc3l4 are expressed abundantly in endothelial cells at embryonic day 8.5. The generation of Exoc3l2 knock-out (KO) mice showed that disruption of Exoc3l2 resulted in lethal in utero. Substantial numbers of Exoc3l2 KO embryos exhibited hemorrhaging. Deletion of Exoc3l2 using Tie2-Cre transgenic mice demonstrated that Exoc3l2 in hematopoietic and endothelial lineages was responsible for the phenotype. Taken together, these findings reveal that Exoc3l2 is essential for cardiovascular and brain development in mice.
Collapse
Affiliation(s)
- Chisato Watanabe
- Department of Stem Cells and Human Disease Models, Research Center for Animal Life Science, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu 520-2192, Japan
| | - Hirotoshi Shibuya
- Technology and Development Team for Mouse Phenotype Analysis, RIKEN BioResource Research Center, Tsukuba 305-0074, Japan
| | - Yusuke Ichiyama
- Department of Ophthalmology, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu 520-2192, Japan
| | - Eiichi Okamura
- Department of Stem Cells and Human Disease Models, Research Center for Animal Life Science, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu 520-2192, Japan
| | - Setsuko Tsukiyama-Fujii
- Department of Stem Cells and Human Disease Models, Research Center for Animal Life Science, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu 520-2192, Japan
| | - Tomoyuki Tsukiyama
- Department of Stem Cells and Human Disease Models, Research Center for Animal Life Science, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu 520-2192, Japan
| | - Shoma Matsumoto
- Department of Stem Cells and Human Disease Models, Research Center for Animal Life Science, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu 520-2192, Japan
| | - Jun Matsushita
- Department of Stem Cells and Human Disease Models, Research Center for Animal Life Science, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu 520-2192, Japan
| | - Takuya Azami
- Department of Stem Cells and Human Disease Models, Research Center for Animal Life Science, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu 520-2192, Japan
| | - Yoshiaki Kubota
- Department of Anatomy, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Masahito Ohji
- Department of Ophthalmology, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu 520-2192, Japan
| | - Fumihiro Sugiyama
- Laboratory Animal Resource Center in Transborder Medical Research Center, University of Tsukuba, Tsukuba 305-8575, Japan
| | - Satoru Takahashi
- Laboratory Animal Resource Center in Transborder Medical Research Center, University of Tsukuba, Tsukuba 305-8575, Japan
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, Tsukuba 305-8575, Japan
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba 305-8575, Japan
| | - Seiya Mizuno
- Laboratory Animal Resource Center in Transborder Medical Research Center, University of Tsukuba, Tsukuba 305-8575, Japan
| | - Masaru Tamura
- Technology and Development Team for Mouse Phenotype Analysis, RIKEN BioResource Research Center, Tsukuba 305-0074, Japan
- Correspondence: (M.T.); (K.-i.M.); (M.E.); Tel.: +81-29-836-9013 (M.T.); +81-78-974-4632 (ext. 73121) (K.-i.M.); +81-77-548-2334 (M.E.)
| | - Ken-ichi Mizutani
- Laboratory of Stem Cell Biology, Graduate School of Pharmaceutical Sciences, Kobe Gakuin University, Kobe 650-8586, Japan
- Correspondence: (M.T.); (K.-i.M.); (M.E.); Tel.: +81-29-836-9013 (M.T.); +81-78-974-4632 (ext. 73121) (K.-i.M.); +81-77-548-2334 (M.E.)
| | - Masatsugu Ema
- Department of Stem Cells and Human Disease Models, Research Center for Animal Life Science, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu 520-2192, Japan
- Correspondence: (M.T.); (K.-i.M.); (M.E.); Tel.: +81-29-836-9013 (M.T.); +81-78-974-4632 (ext. 73121) (K.-i.M.); +81-77-548-2334 (M.E.)
| |
Collapse
|
11
|
A Novel Role of the TRPM4 Ion Channel in Exocytosis. Cells 2022; 11:cells11111793. [PMID: 35681487 PMCID: PMC9180413 DOI: 10.3390/cells11111793] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 05/20/2022] [Accepted: 05/24/2022] [Indexed: 11/23/2022] Open
Abstract
Under physiological conditions, the widely expressed calcium-activated TRPM4 channel conducts sodium into cells. This sodium influx depolarizes the plasma membrane and reduces the driving force for calcium entry. The aberrant expression or function of TRPM4 has been reported in various diseases, including different types of cancer. TRPM4 is mainly localized in the plasma membrane, but it is also found in intracellular vesicles, which can undergo exocytosis. In this study, we show that calcium-induced exocytosis in the colorectal cancer cell line HCT116 is dependent on TRPM4. In addition, the findings from some studies of prostate cancer cell lines suggest a more general role of TRPM4 in calcium-induced exocytosis in cancer cells. Furthermore, calcium-induced exocytosis depends on TRPM4 ion conductivity. Additionally, an increase in intracellular calcium results in the delivery of TRPM4 to the plasma membrane. This process also depends on TRPM4 ion conductivity. TRPM4-dependent exocytosis and the delivery of TRPM4 to the plasma membrane are mediated by SNARE proteins. Finally, we provide evidence that calcium-induced exocytosis depends on TRPM4 ion conductivity, not within the plasma membrane, but rather in TRPM4-containing vesicles.
Collapse
|
12
|
Dimou S, Dionysopoulou M, Sagia GM, Diallinas G. Golgi-Bypass Is a Major Unconventional Route for Translocation to the Plasma Membrane of Non-Apical Membrane Cargoes in Aspergillus nidulans. Front Cell Dev Biol 2022; 10:852028. [PMID: 35465316 PMCID: PMC9021693 DOI: 10.3389/fcell.2022.852028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 03/03/2022] [Indexed: 11/13/2022] Open
Abstract
Nutrient transporters have been shown to translocate to the plasma membrane (PM) of the filamentous fungus Aspergillus nidulans via an unconventional trafficking route that bypasses the Golgi. This finding strongly suggests the existence of distinct COPII vesicle subpopulations, one following Golgi-dependent conventional secretion and the other directed towards the PM. Here, we address whether Golgi-bypass concerns cargoes other than nutrient transporters and whether Golgi-bypass is related to cargo structure, size, abundance, physiological function, or polar vs. non-polar distribution in the PM. To address these questions, we followed the dynamic subcellular localization of two selected membrane cargoes differing in several of the aforementioned aspects. These are the proton-pump ATPase PmaA and the PalI pH signaling component. Our results show that neosynthesized PmaA and PalI are translocated to the PM via Golgi-bypass, similar to nutrient transporters. In addition, we showed that the COPII-dependent exit of PmaA from the ER requires the alternative COPII coat subunit LstA, rather than Sec24, whereas PalI requires the ER cargo adaptor Erv14. These findings strengthen the evidence of distinct cargo-specific COPII subpopulations and extend the concept of Golgi-independent biogenesis to essential transmembrane proteins, other than nutrient transporters. Overall, our findings point to the idea that Golgi-bypass might not constitute a fungal-specific peculiarity, but rather a novel major and cargo-specific sorting route in eukaryotic cells that has been largely ignored.
Collapse
Affiliation(s)
- Sofia Dimou
- Department of Biology, National and Kapodistrian University of Athens, Panepistimioupolis, Athens, Greece
| | - Mariangela Dionysopoulou
- Department of Biology, National and Kapodistrian University of Athens, Panepistimioupolis, Athens, Greece
| | - Georgia Maria Sagia
- Department of Biology, National and Kapodistrian University of Athens, Panepistimioupolis, Athens, Greece
| | - George Diallinas
- Department of Biology, National and Kapodistrian University of Athens, Panepistimioupolis, Athens, Greece
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology, Heraklion, Greece
- *Correspondence: George Diallinas,
| |
Collapse
|
13
|
Deng K, Thorn P. Presynaptic-like mechanisms and the control of insulin secretion in pancreatic β-cells. Cell Calcium 2022; 104:102585. [DOI: 10.1016/j.ceca.2022.102585] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 03/24/2022] [Accepted: 03/26/2022] [Indexed: 12/18/2022]
|
14
|
Zhang W, Staiger CJ. Revising the Role of Cortical Cytoskeleton during Secretion: Actin and Myosin XI Function in Vesicle Tethering. Int J Mol Sci 2021; 23:317. [PMID: 35008741 PMCID: PMC8745698 DOI: 10.3390/ijms23010317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 12/16/2021] [Accepted: 12/23/2021] [Indexed: 11/16/2022] Open
Abstract
In plants, secretion of cell wall components and membrane proteins plays a fundamental role in growth and development as well as survival in diverse environments. Exocytosis, as the last step of the secretory trafficking pathway, is a highly ordered and precisely controlled process involving tethering, docking, and fusion of vesicles at the plasma membrane (PM) for cargo delivery. Although the exocytic process and machinery are well characterized in yeast and animal models, the molecular players and specific molecular events that underpin late stages of exocytosis in plant cells remain largely unknown. Here, by using the delivery of functional, fluorescent-tagged cellulose synthase (CESA) complexes (CSCs) to the PM as a model system for secretion, as well as single-particle tracking in living cells, we describe a quantitative approach for measuring the frequency of vesicle tethering events. Genetic and pharmacological inhibition of cytoskeletal function, reveal that the initial vesicle tethering step of exocytosis is dependent on actin and myosin XI. In contrast, treatments with the microtubule inhibitor, oryzalin, did not significantly affect vesicle tethering or fusion during CSC exocytosis but caused a minor increase in transient or aborted tethering events. With data from this new quantitative approach and improved spatiotemporal resolution of single particle events during secretion, we generate a revised model for the role of the cortical cytoskeleton in CSC trafficking.
Collapse
Affiliation(s)
- Weiwei Zhang
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA
| | - Christopher J. Staiger
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA
- Center for Plant Biology, College of Agriculture, Purdue University, West Lafayette, IN 47907, USA
| |
Collapse
|
15
|
Chan EHY, Zhou Y, Aerne BL, Holder MV, Weston A, Barry DJ, Collinson L, Tapon N. RASSF8-mediated transport of Echinoid via the exocyst promotes Drosophila wing elongation and epithelial ordering. Development 2021; 148:dev199731. [PMID: 34532737 PMCID: PMC8572004 DOI: 10.1242/dev.199731] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 09/13/2021] [Indexed: 01/14/2023]
Abstract
Cell-cell junctions are dynamic structures that maintain cell cohesion and shape in epithelial tissues. During development, junctions undergo extensive rearrangements to drive the epithelial remodelling required for morphogenesis. This is particularly evident during axis elongation, where neighbour exchanges, cell-cell rearrangements and oriented cell divisions lead to large-scale alterations in tissue shape. Polarised vesicle trafficking of junctional components by the exocyst complex has been proposed to promote junctional rearrangements during epithelial remodelling, but the receptors that allow exocyst docking to the target membranes remain poorly understood. Here, we show that the adherens junction component Ras Association domain family 8 (RASSF8) is required for the epithelial re-ordering that occurs during Drosophila pupal wing proximo-distal elongation. We identify the exocyst component Sec15 as a RASSF8 interactor. Loss of RASSF8 elicits cytoplasmic accumulation of Sec15 and Rab11-containing vesicles. These vesicles also contain the nectin-like homophilic adhesion molecule Echinoid, the depletion of which phenocopies the wing elongation and epithelial packing defects observed in RASSF8 mutants. Thus, our results suggest that RASSF8 promotes exocyst-dependent docking of Echinoid-containing vesicles during morphogenesis.
Collapse
Affiliation(s)
- Eunice H. Y. Chan
- Apoptosis and Proliferation Control Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Yanxiang Zhou
- Apoptosis and Proliferation Control Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Birgit L. Aerne
- Apoptosis and Proliferation Control Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Maxine V. Holder
- Apoptosis and Proliferation Control Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Anne Weston
- Electron Microscopy Science Technology Platform, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - David J. Barry
- Advanced Light Microscopy Science Technology Platform, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Lucy Collinson
- Electron Microscopy Science Technology Platform, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Nicolas Tapon
- Apoptosis and Proliferation Control Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| |
Collapse
|
16
|
Herath TUB, Roy A, Gianfelice A, Ireton K. Shigella flexneri subverts host polarized exocytosis to enhance cell-to-cell spread. Mol Microbiol 2021; 116:1328-1346. [PMID: 34608697 DOI: 10.1111/mmi.14827] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 09/21/2021] [Accepted: 10/01/2021] [Indexed: 11/28/2022]
Abstract
Shigella flexneri is a gram-negative bacterial pathogen that causes dysentery. Critical for disease is the ability of Shigella to use an actin-based motility (ABM) process to spread between cells of the colonic epithelium. ABM transports bacteria to the periphery of host cells, allowing the formation of plasma membrane protrusions that mediate spread to adjacent cells. Here we demonstrate that efficient protrusion formation and cell-to-cell spread of Shigella involves bacterial stimulation of host polarized exocytosis. Using an exocytic probe, we found that exocytosis is locally upregulated in bacterial protrusions in a manner that depends on the Shigella type III secretion system. Experiments involving RNA interference (RNAi) indicate that efficient bacterial protrusion formation and spread require the exocyst, a mammalian multi-protein complex known to mediate polarized exocytosis. In addition, the exocyst component Exo70 and the exocyst regulator RalA were recruited to Shigella protrusions, suggesting that bacteria manipulate exocyst function. Importantly, RNAi-mediated depletion of exocyst proteins or RalA reduced the frequency of protrusion formation and also the lengths of protrusions, demonstrating that the exocyst controls both the initiation and elongation of protrusions. Collectively, our results reveal that Shigella co-opts the exocyst complex to disseminate efficiently in host cell monolayers.
Collapse
Affiliation(s)
- Thilina U B Herath
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| | - Arpita Roy
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| | - Antonella Gianfelice
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| | - Keith Ireton
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| |
Collapse
|
17
|
Ral GTPase is essential for actin dynamics and Golgi apparatus distribution in mouse oocyte maturation. Cell Div 2021; 16:3. [PMID: 34112192 PMCID: PMC8194175 DOI: 10.1186/s13008-021-00071-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 06/02/2021] [Indexed: 11/11/2022] Open
Abstract
Background Ral family is a member of Ras-like GTPase superfamily, which includes RalA and RalB. RalA/B play important roles in many cell biological functions, including cytoskeleton dynamics, cell division, membrane transport, gene expression and signal transduction. However, whether RalA/B involve into the mammalian oocyte meiosis is still unclear. This study aimed to explore the roles of RalA/B during mouse oocyte maturation. Results Our results showed that RalA/B expressed at all stages of oocyte maturation, and they were enriched at the spindle periphery area after meiosis resumption. The injection of RalA/B siRNAs into the oocytes significantly disturbed the polar body extrusion, indicating the essential roles of RalA/B for oocyte maturation. We observed that in the RalA/B knockdown oocytes the actin filament fluorescence intensity was significantly increased at the both cortex and cytoplasm, and the chromosomes were failed to locate near the cortex, indicating that RalA/B regulate actin dynamics for spindle migration in mouse oocytes. Moreover, we also found that the Golgi apparatus distribution at the spindle periphery was disturbed after RalA/B depletion. Conclusions In summary, our results indicated that RalA/B affect actin dynamics for chromosome positioning and Golgi apparatus distribution in mouse oocytes.
Collapse
|
18
|
Duan X, Chen X, Wang K, Chen L, Glomb O, Johnsson N, Feng L, Zhou XQ, Bi E. Essential role of the endocytic site-associated protein Ecm25 in stress-induced cell elongation. Cell Rep 2021; 35:109122. [PMID: 34010635 PMCID: PMC8202958 DOI: 10.1016/j.celrep.2021.109122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 02/16/2021] [Accepted: 04/22/2021] [Indexed: 11/27/2022] Open
Abstract
How cells adopt a different morphology to cope with stress is not well understood. Here, we show that budding yeast Ecm25 associates with polarized endocytic sites and interacts with the polarity regulator Cdc42 and several late-stage endocytic proteins via distinct regions, including an actin filament-binding motif. Deletion of ECM25 does not affect Cdc42 activity or cause any strong defects in fluid-phase and clathrin-mediated endocytosis but completely abolishes hydroxyurea-induced cell elongation. This phenotype is accompanied by depolarization of the spatiotemporally coupled exo-endocytosis in the bud cortex while maintaining the overall mother-bud polarity. These data suggest that Ecm25 provides an essential link between the polarization signal and the endocytic machinery to enable adaptive morphogenesis under stress conditions. How cells adopt a different morphology to cope with stress is not well understood. Duan et al. report that the budding yeast protein Ecm25 plays an essential role in stress-induced cell elongation by linking the polarity regulator Cdc42 to the late-stage endocytic machinery.
Collapse
Affiliation(s)
- Xudong Duan
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6058, USA; Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, 611130 Sichuan, China; Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China
| | - Xi Chen
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6058, USA
| | - Kangji Wang
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6058, USA
| | - Li Chen
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6058, USA
| | - Oliver Glomb
- Institut für Molekulare Genetik und Zellbiologie, Universität Ulm, 89081 Ulm, Germany
| | - Nils Johnsson
- Institut für Molekulare Genetik und Zellbiologie, Universität Ulm, 89081 Ulm, Germany
| | - Lin Feng
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, 611130 Sichuan, China
| | - Xiao-Qiu Zhou
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, 611130 Sichuan, China.
| | - Erfei Bi
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6058, USA.
| |
Collapse
|
19
|
Functional compartmentalization of photoreceptor neurons. Pflugers Arch 2021; 473:1493-1516. [PMID: 33880652 DOI: 10.1007/s00424-021-02558-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 03/15/2021] [Accepted: 03/22/2021] [Indexed: 12/16/2022]
Abstract
Retinal photoreceptors are neurons that convert dynamically changing patterns of light into electrical signals that are processed by retinal interneurons and ultimately transmitted to vision centers in the brain. They represent the essential first step in seeing without which the remainder of the visual system is rendered moot. To support this role, the major functions of photoreceptors are segregated into three main specialized compartments-the outer segment, the inner segment, and the pre-synaptic terminal. This compartmentalization is crucial for photoreceptor function-disruption leads to devastating blinding diseases for which therapies remain elusive. In this review, we examine the current understanding of the molecular and physical mechanisms underlying photoreceptor functional compartmentalization and highlight areas where significant knowledge gaps remain.
Collapse
|
20
|
The Kunitz-type serine protease inhibitor Spint2 is required for cellular cohesion, coordinated cell migration and cell survival during zebrafish hatching gland development. Dev Biol 2021; 476:148-170. [PMID: 33826923 DOI: 10.1016/j.ydbio.2021.03.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 02/19/2021] [Accepted: 03/19/2021] [Indexed: 12/23/2022]
Abstract
We have previously shown that the Kunitz-type serine protease inhibitor Spint1a, also named Hai1a, is required in the zebrafish embryonic epidermis to restrict the activity of the type II transmembrane serine protease (TTSP) Matriptase1a/St14a, thereby ensuring epidermal homeostasis. A closely related Kunitz-type inhibitor is Spint2/Hai2, which in mammals plays multiple developmental roles that are either redundant or non-redundant with those of Spint1. However, the molecular bases for these non-redundancies are not fully understood. Here, we study spint2 during zebrafish development. It is co-expressed with spint1a in multiple embryonic epithelia, including the outer/peridermal layer of the epidermis. However, unlike spint1a, spint2 expression is absent from the basal epidermal layer but present in hatching gland cells. Hatching gland cells derive from the mesendodermal prechordal plate, from where they undergo a thus far undescribed transit into, and coordinated sheet migration within, the interspace between the outer and basal layer of the epidermis to reach their final destination on the yolk sac. Hatching gland cells usually survive their degranulation that drives embryo hatching but die several days later. In spint2 mutants, cohesion among hatching gland cells and their collective intra-epidermal migration are disturbed, leading to a discontinuous organization of the gland. In addition, cells undergo precocious cell death before degranulation, so that embryos fail to hatch. Chimera analyses show that Spint2 is required in hatching gland cells, but not in the overlying periderm, their potential migration and adhesion substrate. Spint2 acts independently of all tested Matriptases, Prostasins and other described Spint1 and Spint2 mediators. However, it displays a tight genetic interaction with and acts at least partly via the cell-cell adhesion protein E-cadherin, promoting both hatching gland cell cohesiveness and survival, in line with formerly reported effects of E-cadherin during morphogenesis and cell death suppression. In contrast, no such genetic interaction was observed between Spint2 and the cell-cell adhesion molecule EpCAM, which instead interacts with Spint1a. Our data shed new light onto the mechanisms of hatching gland morphogenesis and hatching gland cell survival. In addition, they reveal developmental roles of Spint2 that are strikingly different from those of Spint1, most likely due to differences in the expression patterns and relevant target proteins.
Collapse
|
21
|
Zheng Y, Xing L, Chen L, Zhou R, Wu J, Zhu X, Li L, Xiang Y, Wu R, Zhang L, Huang Y. Tailored elasticity combined with biomimetic surface promotes nanoparticle transcytosis to overcome mucosal epithelial barrier. Biomaterials 2020; 262:120323. [DOI: 10.1016/j.biomaterials.2020.120323] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 08/09/2020] [Accepted: 08/11/2020] [Indexed: 12/13/2022]
|
22
|
Dimou S, Diallinas G. Life and Death of Fungal Transporters under the Challenge of Polarity. Int J Mol Sci 2020; 21:ijms21155376. [PMID: 32751072 PMCID: PMC7432044 DOI: 10.3390/ijms21155376] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 07/24/2020] [Accepted: 07/27/2020] [Indexed: 12/14/2022] Open
Abstract
Eukaryotic plasma membrane (PM) transporters face critical challenges that are not widely present in prokaryotes. The two most important issues are proper subcellular traffic and targeting to the PM, and regulated endocytosis in response to physiological, developmental, or stress signals. Sorting of transporters from their site of synthesis, the endoplasmic reticulum (ER), to the PM has been long thought, but not formally shown, to occur via the conventional Golgi-dependent vesicular secretory pathway. Endocytosis of specific eukaryotic transporters has been studied more systematically and shown to involve ubiquitination, internalization, and sorting to early endosomes, followed by turnover in the multivesicular bodies (MVB)/lysosomes/vacuole system. In specific cases, internalized transporters have been shown to recycle back to the PM. However, the mechanisms of transporter forward trafficking and turnover have been overturned recently through systematic work in the model fungus Aspergillus nidulans. In this review, we present evidence that shows that transporter traffic to the PM takes place through Golgi bypass and transporter endocytosis operates via a mechanism that is distinct from that of recycling membrane cargoes essential for fungal growth. We discuss these findings in relation to adaptation to challenges imposed by cell polarity in fungi as well as in other eukaryotes and provide a rationale of why transporters and possibly other housekeeping membrane proteins ‘avoid’ routes of polar trafficking.
Collapse
|
23
|
Wang Y, Brieher WM. CD2AP links actin to PI3 kinase activity to extend epithelial cell height and constrain cell area. J Cell Biol 2020; 219:jcb.201812087. [PMID: 31723006 PMCID: PMC7039212 DOI: 10.1083/jcb.201812087] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 08/26/2019] [Accepted: 10/21/2019] [Indexed: 01/03/2023] Open
Abstract
Epithelial cells are categorized as cuboidal versus squamous based on the height of the lateral membrane. Wang and Brieher show that CD2AP links PI3K activity to actin assembly to extend the height of the lateral membrane. Maintaining the correct ratio of apical, basal, and lateral membrane domains is important for epithelial physiology. Here, we show that CD2AP is a critical determinant of epithelial membrane proportions. Depletion of CD2AP or phosphoinositide 3-kinase (PI3K) inhibition results in loss of F-actin and expansion of apical–basal domains, which comes at the expense of lateral membrane height in MDCK cells. We demonstrate that the SH3 domains of CD2AP bind to PI3K and are necessary for PI3K activity along lateral membranes and constraining cell area. Tethering the SH3 domains of CD2AP or p110γ to the membrane is sufficient to rescue CD2AP-knockdown phenotypes. CD2AP and PI3K are both upstream and downstream of actin polymerization. Since CD2AP binds to both actin filaments and PI3K, CD2AP might bridge actin assembly to PI3K activation to form a positive feedback loop to support lateral membrane extension. Our results provide insight into the squamous to cuboidal to columnar epithelial transitions seen in complex epithelial tissues in vivo.
Collapse
Affiliation(s)
- Yuou Wang
- Department of Cell and Developmental Biology, University of Illinois, Urbana-Champaign, Urbana, IL
| | - William M Brieher
- Department of Cell and Developmental Biology, University of Illinois, Urbana-Champaign, Urbana, IL
| |
Collapse
|
24
|
Dimou S, Martzoukou O, Dionysopoulou M, Bouris V, Amillis S, Diallinas G. Translocation of nutrient transporters to cell membrane via Golgi bypass in Aspergillus nidulans. EMBO Rep 2020; 21:e49929. [PMID: 32452614 DOI: 10.15252/embr.201949929] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 04/15/2020] [Accepted: 04/24/2020] [Indexed: 02/06/2023] Open
Abstract
Nutrient transporters, being polytopic membrane proteins, are believed, but not formally shown, to traffic from their site of synthesis, the ER, to the plasma membrane through Golgi-dependent vesicular trafficking. Here, we develop a novel genetic system to investigate the trafficking of a neosynthesized model transporter, the well-studied UapA purine transporter of Aspergillus nidulans. We show that sorting of neosynthesized UapA to the plasma membrane (PM) bypasses the Golgi and does not necessitate key Rab GTPases, AP adaptors, microtubules or endosomes. UapA PM localization is found to be dependent on functional COPII vesicles, actin polymerization, clathrin heavy chain and the PM t-SNARE SsoA. Actin polymerization proved to primarily affect COPII vesicle formation, whereas the essential role of ClaH seems indirect and less clear. We provide evidence that other evolutionary and functionally distinct transporters of A. nidulans also follow the herein identified Golgi-independent trafficking route of UapA. Importantly, our findings suggest that specific membrane cargoes drive the formation of distinct COPII subpopulations that bypass the Golgi to be sorted non-polarly to the PM, and thus serving house-keeping cell functions.
Collapse
Affiliation(s)
- Sofia Dimou
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Olga Martzoukou
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | | | - Vangelis Bouris
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Sotiris Amillis
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - George Diallinas
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| |
Collapse
|
25
|
Ganesan SJ, Feyder MJ, Chemmama IE, Fang F, Rout MP, Chait BT, Shi Y, Munson M, Sali A. Integrative structure and function of the yeast exocyst complex. Protein Sci 2020; 29:1486-1501. [PMID: 32239688 DOI: 10.1002/pro.3863] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 03/25/2020] [Accepted: 03/27/2020] [Indexed: 12/13/2022]
Abstract
Exocyst is an evolutionarily conserved hetero-octameric tethering complex that plays a variety of roles in membrane trafficking, including exocytosis, endocytosis, autophagy, cell polarization, cytokinesis, pathogen invasion, and metastasis. Exocyst serves as a platform for interactions between the Rab, Rho, and Ral small GTPases, SNARE proteins, and Sec1/Munc18 regulators that coordinate spatial and temporal fidelity of membrane fusion. However, its mechanism is poorly described at the molecular level. Here, we determine the molecular architecture of the yeast exocyst complex by an integrative approach, based on a 3D density map from negative-stain electron microscopy (EM) at ~16 Å resolution, 434 disuccinimidyl suberate and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride cross-links from chemical-crosslinking mass spectrometry, and partial atomic models of the eight subunits. The integrative structure is validated by a previously determined cryo-EM structure, cross-links, and distances from in vivo fluorescence microscopy. Our subunit configuration is consistent with the cryo-EM structure, except for Sec5. While not observed in the cryo-EM map, the integrative model localizes the N-terminal half of Sec3 near the Sec6 subunit. Limited proteolysis experiments suggest that the conformation of Exo70 is dynamic, which may have functional implications for SNARE and membrane interactions. This study illustrates how integrative modeling based on varied low-resolution structural data can inform biologically relevant hypotheses, even in the absence of high-resolution data.
Collapse
Affiliation(s)
- Sai J Ganesan
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, California, USA.,Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California, USA
| | - Michael J Feyder
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Ilan E Chemmama
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, California, USA.,Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California, USA
| | - Fei Fang
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Michael P Rout
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, New York, USA
| | - Brian T Chait
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, New York, USA
| | - Yi Shi
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Mary Munson
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Andrej Sali
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, California, USA.,Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California, USA
| |
Collapse
|
26
|
Seitz S, Kwon Y, Hartleben G, Jülg J, Sekar R, Krahmer N, Najafi B, Loft A, Gancheva S, Stemmer K, Feuchtinger A, Hrabe de Angelis M, Müller TD, Mann M, Blüher M, Roden M, Berriel Diaz M, Behrends C, Gilleron J, Herzig S, Zeigerer A. Hepatic Rab24 controls blood glucose homeostasis via improving mitochondrial plasticity. Nat Metab 2019; 1:1009-1026. [PMID: 32694843 DOI: 10.1038/s42255-019-0124-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 09/10/2019] [Indexed: 12/18/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) represents a key feature of obesity-related type 2 diabetes with increasing prevalence worldwide. To our knowledge, no treatment options are available to date, paving the way for more severe liver damage, including cirrhosis and hepatocellular carcinoma. Here, we show an unexpected function for an intracellular trafficking regulator, the small Rab GTPase Rab24, in mitochondrial fission and activation, which has an immediate impact on hepatic and systemic energy homeostasis. RAB24 is highly upregulated in the livers of obese patients with NAFLD and positively correlates with increased body fat in humans. Liver-selective inhibition of Rab24 increases autophagic flux and mitochondrial connectivity, leading to a strong improvement in hepatic steatosis and a reduction in serum glucose and cholesterol levels in obese mice. Our study highlights a potential therapeutic application of trafficking regulators, such as RAB24, for NAFLD and establishes a conceptual functional connection between intracellular transport and systemic metabolic dysfunction.
Collapse
Affiliation(s)
- Susanne Seitz
- Institute for Diabetes and Cancer, Helmholtz Center Munich, Neuherberg, Germany
- German Center for Diabetes Research, Neuherberg, Germany
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany
| | - Yun Kwon
- Institute for Diabetes and Cancer, Helmholtz Center Munich, Neuherberg, Germany
- German Center for Diabetes Research, Neuherberg, Germany
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany
| | - Götz Hartleben
- Institute for Diabetes and Cancer, Helmholtz Center Munich, Neuherberg, Germany
- German Center for Diabetes Research, Neuherberg, Germany
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany
| | - Julia Jülg
- Munich Cluster for Systems Neurology, Ludwig-Maximilians-University München, Munich, Germany
| | - Revathi Sekar
- Institute for Diabetes and Cancer, Helmholtz Center Munich, Neuherberg, Germany
- German Center for Diabetes Research, Neuherberg, Germany
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany
| | - Natalie Krahmer
- German Center for Diabetes Research, Neuherberg, Germany
- Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany
- Institute for Diabetes and Obesity, Helmholtz Center Munich, Neuherberg, Germany
| | - Bahar Najafi
- Institute for Diabetes and Cancer, Helmholtz Center Munich, Neuherberg, Germany
- German Center for Diabetes Research, Neuherberg, Germany
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany
| | - Anne Loft
- Institute for Diabetes and Cancer, Helmholtz Center Munich, Neuherberg, Germany
- German Center for Diabetes Research, Neuherberg, Germany
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany
| | - Sofiya Gancheva
- German Center for Diabetes Research, Neuherberg, Germany
- Division of Endocrinology and Diabetology, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University, Düsseldorf, Germany
| | - Kerstin Stemmer
- German Center for Diabetes Research, Neuherberg, Germany
- Institute for Diabetes and Obesity, Helmholtz Center Munich, Neuherberg, Germany
| | - Annette Feuchtinger
- Research Unit Analytical Pathology, Helmholtz Center Munich, Neuherberg, Germany
| | - Martin Hrabe de Angelis
- German Center for Diabetes Research, Neuherberg, Germany
- Institute of Experimental Genetics, Helmholtz Center Munich German Research Center for Environmental Health, Neuherberg, Germany
- Chair of Experimental Genetics, School of Life Science Weihenstephan, Technische Universität München, Freising, Germany
| | - Timo D Müller
- German Center for Diabetes Research, Neuherberg, Germany
- Institute for Diabetes and Obesity, Helmholtz Center Munich, Neuherberg, Germany
- Department of Pharmacology and Experimental Therapy, Institute of Experimental and Clinical Pharmacology and Toxicology, Eberhard Karls University Hospitals and Clinics, Tübingen, Germany
| | - Matthias Mann
- Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany
- NF Center for Protein Research, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Matthias Blüher
- Department of Medicine, University of Leipzig, Leipzig, Germany
| | - Michael Roden
- German Center for Diabetes Research, Neuherberg, Germany
- Division of Endocrinology and Diabetology, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University, Düsseldorf, Germany
| | - Mauricio Berriel Diaz
- Institute for Diabetes and Cancer, Helmholtz Center Munich, Neuherberg, Germany
- German Center for Diabetes Research, Neuherberg, Germany
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany
| | - Christian Behrends
- Munich Cluster for Systems Neurology, Ludwig-Maximilians-University München, Munich, Germany
| | - Jerome Gilleron
- Université Côte d'Azur, Institut National de la Santé et de la Recherche Médicale UMR1065, Centre Méditerranéen de Médecine Moléculaire (C3M), Nice, France
| | - Stephan Herzig
- Institute for Diabetes and Cancer, Helmholtz Center Munich, Neuherberg, Germany
- German Center for Diabetes Research, Neuherberg, Germany
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany
- Chair Molecular Metabolic Control, Technical University Munich, Munich, Germany
| | - Anja Zeigerer
- Institute for Diabetes and Cancer, Helmholtz Center Munich, Neuherberg, Germany.
- German Center for Diabetes Research, Neuherberg, Germany.
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany.
| |
Collapse
|
27
|
Ranjan P, Awasthi M, Snell WJ. Transient Internalization and Microtubule-Dependent Trafficking of a Ciliary Signaling Receptor from the Plasma Membrane to the Cilium. Curr Biol 2019; 29:2942-2947.e2. [PMID: 31422889 DOI: 10.1016/j.cub.2019.07.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 07/03/2019] [Accepted: 07/09/2019] [Indexed: 12/24/2022]
Abstract
Cilia are ancient organelles used by unicellular and multicellular organisms not only for motility but also to receive and respond to multiple environmental cues, including light, odorants, morphogens, growth factors, and contact with cilia of other cells. Much is known about the cellular mechanisms that deliver membrane proteins to cilia during ciliogenesis. Execution of a ciliary signaling pathway, however, can critically depend on rapid alterations in the receptor composition of the cilium itself, and our understanding of the mechanisms that underlie these rapid, regulated alterations remains limited [1-6]. In the bi-ciliated, unicellular alga Chlamydomonas reinhardtii, interactions between cilia of mating type plus and mating type minus gametes mediated by adhesion receptors SAG1 and SAD1 activate a ciliary signaling pathway [7]. In response, a large, inactive pool of SAG1 on the plasma membrane of plus gametes rapidly becomes enriched in the peri-ciliary membrane and enters the cilia to become active and maintain and enhance ciliary adhesion and signaling [8-14]. Ciliary entry per se of SAG1 is independent of anterograde intraflagellar transport (IFT) [13], but the rapid apical enrichment requires cytoplasmic microtubules and the retrograde IFT motor, dynein 1b [14]. Whether the receptors move laterally within the plasma membrane or transit internally during redistribution is unknown. Here, in coupled immunolocalization/biochemical studies on SAG1, we show that, within minutes after gamete activation is initiated, cell-surface SAG1 is internalized, associates with an apico-basally polarized array of cytoplasmic microtubules, and returns to the cell surface at a peri-ciliary staging area for entry into cilia.
Collapse
Affiliation(s)
- Peeyush Ranjan
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA
| | - Mayanka Awasthi
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA
| | - William J Snell
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA.
| |
Collapse
|
28
|
Sáez JJ, Diaz J, Ibañez J, Bozo JP, Cabrera Reyes F, Alamo M, Gobert FX, Obino D, Bono MR, Lennon-Duménil AM, Yeaman C, Yuseff MI. The exocyst controls lysosome secretion and antigen extraction at the immune synapse of B cells. J Cell Biol 2019; 218:2247-2264. [PMID: 31197029 PMCID: PMC6605794 DOI: 10.1083/jcb.201811131] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 04/11/2019] [Accepted: 05/22/2019] [Indexed: 02/06/2023] Open
Abstract
BCR engagement enhances microtubule stability, which triggers the mobilization of Exo70 from the centrosome to the immune synapse. BCR engagement activates GEF-H1, which promotes exocyst assembly required for the docking and secretion of lysosomes, facilitating the extraction of surface-tethered antigens. B lymphocytes capture antigens from the surface of presenting cells by forming an immune synapse. Local secretion of lysosomes, which are guided to the synaptic membrane by centrosome repositioning, can facilitate the extraction of immobilized antigens. However, the molecular basis underlying their delivery to precise domains of the plasma membrane remains elusive. Here we show that microtubule stabilization, triggered by engagement of the B cell receptor, acts as a cue to release centrosome-associated Exo70, which is redistributed to the immune synapse. This process is coupled to the recruitment and activation of GEF-H1, which is required for assembly of the exocyst complex, used to promote tethering and fusion of lysosomes at the immune synapse. B cells silenced for GEF-H1 or Exo70 display defective lysosome secretion, which results in impaired antigen extraction and presentation. Thus, centrosome repositioning coupled to changes in microtubule stability orchestrates the spatial-temporal distribution of the exocyst complex to promote polarized lysosome secretion at the immune synapse.
Collapse
Affiliation(s)
- Juan José Sáez
- Department of Cellular and Molecular Biology, Faculty of Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile.,Department of Biology, Faculty of Sciences, Universidad de Chile, Santiago, Chile
| | - Jheimmy Diaz
- Department of Cellular and Molecular Biology, Faculty of Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Jorge Ibañez
- Department of Cellular and Molecular Biology, Faculty of Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Juan Pablo Bozo
- Department of Cellular and Molecular Biology, Faculty of Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Fernanda Cabrera Reyes
- Department of Cellular and Molecular Biology, Faculty of Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Martina Alamo
- Department of Cellular and Molecular Biology, Faculty of Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - François-Xavier Gobert
- INSERM U932, Institut Curie, Centre de Recherche, PSL Research University, Paris, Île-de-France, France
| | - Dorian Obino
- INSERM U932, Institut Curie, Centre de Recherche, PSL Research University, Paris, Île-de-France, France
| | - María Rosa Bono
- Department of Biology, Faculty of Sciences, Universidad de Chile, Santiago, Chile
| | - Ana-María Lennon-Duménil
- INSERM U932, Institut Curie, Centre de Recherche, PSL Research University, Paris, Île-de-France, France
| | - Charles Yeaman
- Department of Anatomy and Cell Biology, University of Iowa, Iowa City, IA
| | - María-Isabel Yuseff
- Department of Cellular and Molecular Biology, Faculty of Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| |
Collapse
|
29
|
Live-Cell Structural Biology to Solve Biological Mechanisms: The Case of the Exocyst. Structure 2019; 27:886-892. [DOI: 10.1016/j.str.2019.04.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 04/01/2019] [Accepted: 04/18/2019] [Indexed: 01/24/2023]
|
30
|
Zhang T, Sun D, Luo G, Liu Y. Spatial and Translational Regulation of Exocyst Subunits by Cell Cycle in Budding Yeast. Med Sci Monit 2019; 25:4059-4067. [PMID: 31150370 PMCID: PMC6559343 DOI: 10.12659/msm.914194] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Previous studies have shown that exocyst complex is located at polarized growth sites at different cell cycle stages in budding yeast. But how cell cycle and the cyclin-dependent kinase, Cdk1, regulate the distribution of exocyst complex on the plasma membrane and the protein level of each exocyst subunit is not clear. MATERIAL AND METHODS Using budding yeast as a research material, regulation of cell cycle and Cdk1 on exocyst localization on the plasma membrane and on level of each exocyst subunit were examined by methods of cell biology and molecular biology. RESULTS Exocyst complex is located at growth sites on the plasma membrane in both budding and non-budding stages. Cdk1 activity is required for polarized distribution of exocyst complex in late G1, S and M phases, but not in cytokinesis stage. Cdk1 is not required for the assembly and localization of exocyst complex on plasma membrane. The protein level of Sec3 but not other exocyst subunits is regulated by the cell cycle. CONCLUSIONS Cdk1 activity is required for exocyst polarization before cytokinesis during the cell cycle progression, but not for its assembly and localization on the plasma membrane. Dynamic localization and protein level of the complex subunits are regulated by the cell cycle.
Collapse
Affiliation(s)
- Tianrui Zhang
- Department of Biochemistry and Molecular Biology, China Medical University, Shenyang, Liaoning, China (mainland)
| | - Dong Sun
- Institute of Translational Research, China Medical University, Shenyang, Liaoning, China (mainland)
| | - Guangzuo Luo
- Institute of Translational Research, China Medical University, Shenyang, Liaoning, China (mainland)
| | - Ying Liu
- Department of Biochemistry and Molecular Biology, China Medical University, Shenyang, Liaoning, China (mainland)
| |
Collapse
|
31
|
Molecular mechanisms of contractile-ring constriction and membrane trafficking in cytokinesis. Biophys Rev 2018; 10:1649-1666. [PMID: 30448943 DOI: 10.1007/s12551-018-0479-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 11/06/2018] [Indexed: 12/14/2022] Open
Abstract
In this review, we discuss the molecular mechanisms of cytokinesis from plants to humans, with a focus on contribution of membrane trafficking to cytokinesis. Selection of the division site in fungi, metazoans, and plants is reviewed, as well as the assembly and constriction of a contractile ring in fungi and metazoans. We also provide an introduction to exocytosis and endocytosis, and discuss how they contribute to successful cytokinesis in eukaryotic cells. The conservation in the coordination of membrane deposition and cytoskeleton during cytokinesis in fungi, metazoans, and plants is highlighted.
Collapse
|
32
|
Lepore DM, Martínez-Núñez L, Munson M. Exposing the Elusive Exocyst Structure. Trends Biochem Sci 2018; 43:714-725. [PMID: 30055895 PMCID: PMC6108956 DOI: 10.1016/j.tibs.2018.06.012] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Revised: 06/18/2018] [Accepted: 06/29/2018] [Indexed: 11/18/2022]
Abstract
A major challenge for a molecular understanding of membrane trafficking has been the elucidation of high-resolution structures of large, multisubunit tethering complexes that spatially and temporally control intracellular membrane fusion. Exocyst is a large hetero-octameric protein complex proposed to tether secretory vesicles at the plasma membrane to provide quality control of soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE)-mediated membrane fusion. Breakthroughs in methodologies, including sample preparation, biochemical characterization, fluorescence microscopy, and single-particle cryoelectron microscopy, are providing critical insights into the structure and function of the exocyst. These studies now pose more questions than answers for understanding fundamental functional mechanisms, and they open wide the door for future studies to elucidate interactions with protein and membrane partners, potential conformational changes, and molecular insights into tethering reactions.
Collapse
Affiliation(s)
- Dante M Lepore
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605, USA
| | - Leonora Martínez-Núñez
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605, USA
| | - Mary Munson
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605, USA.
| |
Collapse
|
33
|
Sachdev U, Lotze MT. Perpetual change: autophagy, the endothelium, and response to vascular injury. J Leukoc Biol 2017; 102:221-235. [PMID: 28626046 PMCID: PMC6608075 DOI: 10.1189/jlb.3ru1116-484rr] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 05/05/2017] [Accepted: 05/08/2017] [Indexed: 12/15/2022] Open
Abstract
Current studies of vascular health, aging, and autophagy emphasize how the endothelium adapts to stress and contributes to disease. The endothelium is far from an inert barrier to blood-borne cells, pathogens, and chemical signals; rather, it actively translates circulating mediators into tissue responses, changing rapidly in response to physiologic stressors. Macroautophagy-the cellular ingestion of effete organelles and protein aggregates to provide anabolic substrates to fuel bioenergetics in times of stress-plays an important role in endothelial cell homeostasis, vascular remodeling, and disease. These roles include regulating vascular tone, sustaining or limiting cell survival, and contributing to the development of atherosclerosis secondary to infection, inflammation, and angiogenesis. Autophagy modulates these critical functions of the endothelium in a dynamic and perpetual response to tissue and intravascular cues.
Collapse
Affiliation(s)
- Ulka Sachdev
- Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Michael T Lotze
- Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| |
Collapse
|