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Abstract
Mapping proteins in and associated with the Golgi apparatus reveals how this cellular compartment emerges in budding yeast and progresses over time.
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Affiliation(s)
- Jurgen Denecke
- Centre for Plant Sciences, School of Biology, Faculty of Biological Sciences, University of LeedsLeedsUnited Kingdom
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2
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Kanemaki R, Hayakawa T, Kudo H, Yohda M, Fukutani Y. Identification of two critical amino acid residues in short-chain aldehyde-responsive odorant receptors. J Biochem 2024:mvae033. [PMID: 38564195 DOI: 10.1093/jb/mvae033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 03/14/2024] [Accepted: 03/22/2024] [Indexed: 04/04/2024] Open
Abstract
Mammalian odorant receptors (ORs) are crucial for detecting a broad spectrum of odorants, yet their functional expression poses a significant challenge, often requiring Receptor-transporting proteins (RTPs). This study examines mouse Olfr733 and Olfr732, which, despite high homology, show different functional expression profiles in heterologous cell systems. Our research aimed to identify key amino acids impacting Olfr733's functional expression. We discovered that G112FBW3.40 and L148PBW4.49 (Ballesteros-Weinstein numbering in superscript) substitutions in Olfr732 markedly enhance its RTP-independent expression and ligand responsiveness, mirroring Olfr733. These substitutions, particularly Phe112 and Leu148, are crucial for aldehyde recognition and membrane localization in Olfr733, respectively. While Olfr732-type ORs are conserved across species, Olfr733-types, unique to specific rodents, appear to have evolved from Olfr732, with Pro148 enhancing membrane expression and aldehyde sensitivity. Mouse ORs with ProBW4.49 tend to exhibit improved membrane expression compared to their paralogs, especially when co-expressed with RTP1S. This study concludes that the Pro residue in the fourth transmembrane domain significantly contributes to the structural stability of certain olfactory receptors, highlighting the intricate molecular mechanisms underlying OR functionality and evolution.
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Affiliation(s)
- Reina Kanemaki
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Toshiya Hayakawa
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Haruto Kudo
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Masafumi Yohda
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Yosuke Fukutani
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
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3
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Tojima T, Suda Y, Jin N, Kurokawa K, Nakano A. Spatiotemporal dissection of the Golgi apparatus and the ER-Golgi intermediate compartment in budding yeast. eLife 2024; 13:e92900. [PMID: 38501165 PMCID: PMC10950332 DOI: 10.7554/elife.92900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Accepted: 02/23/2024] [Indexed: 03/20/2024] Open
Abstract
Cargo traffic through the Golgi apparatus is mediated by cisternal maturation, but it remains largely unclear how the cis-cisternae, the earliest Golgi sub-compartment, is generated and how the Golgi matures into the trans-Golgi network (TGN). Here, we use high-speed and high-resolution confocal microscopy to analyze the spatiotemporal dynamics of a diverse set of proteins that reside in and around the Golgi in budding yeast. We find many mobile punctate structures that harbor yeast counterparts of mammalian endoplasmic reticulum (ER)-Golgi intermediate compartment (ERGIC) proteins, which we term 'yeast ERGIC'. It occasionally exhibits approach and contact behavior toward the ER exit sites and gradually matures into the cis-Golgi. Upon treatment with the Golgi-disrupting agent brefeldin A, the ERGIC proteins form larger aggregates corresponding to the Golgi entry core compartment in plants, while cis- and medial-Golgi proteins are absorbed into the ER. We further analyze the dynamics of several late Golgi proteins to better understand the Golgi-TGN transition. Together with our previous studies, we demonstrate a detailed spatiotemporal profile of the entire cisternal maturation process from the ERGIC to the Golgi and further to the TGN.
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Grants
- KAKENHI 19K06669 Ministry of Education, Culture, Sports, Science and Technology
- KAKENHI 19H04764 Ministry of Education, Culture, Sports, Science and Technology
- KAKENHI 22K06213 Ministry of Education, Culture, Sports, Science and Technology
- CREST JPMJCR21E3 Japan Science and Technology Agency
- KAKENHI 17H06420 Ministry of Education, Culture, Sports, Science and Technology
- KAKENHI 18H05275 Ministry of Education, Culture, Sports, Science and Technology
- KAKENHI 23H00382 Ministry of Education, Culture, Sports, Science and Technology
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Affiliation(s)
- Takuro Tojima
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced PhotonicsWakoJapan
| | - Yasuyuki Suda
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced PhotonicsWakoJapan
- Laboratory of Molecular Cell Biology, Faculty of Medicine, University of TsukubaTsukubaJapan
| | - Natsuko Jin
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced PhotonicsWakoJapan
| | - Kazuo Kurokawa
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced PhotonicsWakoJapan
| | - Akihiko Nakano
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced PhotonicsWakoJapan
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4
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Holzer E, Martens S, Tulli S. The Role of ATG9 Vesicles in Autophagosome Biogenesis. J Mol Biol 2024:168489. [PMID: 38342428 DOI: 10.1016/j.jmb.2024.168489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 02/02/2024] [Accepted: 02/07/2024] [Indexed: 02/13/2024]
Abstract
Autophagy mediates the degradation and recycling of cellular material in the lysosomal system. Dysfunctional autophagy is associated with a plethora of diseases including uncontrolled infections, cancer and neurodegeneration. In macroautophagy (hereafter autophagy) this material is encapsulated in double membrane vesicles, the autophagosomes, which form upon induction of autophagy. The precursors to autophagosomes, referred to as phagophores, first appear as small flattened membrane cisternae, which gradually enclose the cargo material as they grow. The assembly of phagophores during autophagy initiation has been a major subject of investigation over the past decades. A special focus has been ATG9, the only conserved transmembrane protein among the core machinery. The majority of ATG9 localizes to small Golgi-derived vesicles. Here we review the recent advances and breakthroughs regarding our understanding of how ATG9 and the vesicles it resides in serve to assemble the autophagy machinery and to establish membrane contact sites for autophagosome biogenesis. We also highlight open questions in the field that need to be addressed in the years to come.
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Affiliation(s)
- Elisabeth Holzer
- Max Perutz Labs, Vienna BioCenter Campus (VBC), Vienna, Austria; University of Vienna, Max Perutz Labs, Department of Biochemistry and Cell Biology, Vienna, Austria; Vienna BioCenter PhD Program, Doctoral School of the University of Vienna and Medical University of Vienna, Campus-Vienna-Biocenter 1, Vienna, Austria.
| | - Sascha Martens
- Max Perutz Labs, Vienna BioCenter Campus (VBC), Vienna, Austria; University of Vienna, Max Perutz Labs, Department of Biochemistry and Cell Biology, Vienna, Austria.
| | - Susanna Tulli
- Max Perutz Labs, Vienna BioCenter Campus (VBC), Vienna, Austria; University of Vienna, Max Perutz Labs, Department of Biochemistry and Cell Biology, Vienna, Austria.
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5
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Baena G, Xia L, Waghmare S, Yu Z, Guo Y, Blatt MR, Zhang B, Karnik R. Arabidopsis SNARE SYP132 impacts on PIP2;1 trafficking and function in salinity stress. Plant J 2024. [PMID: 38289468 DOI: 10.1111/tpj.16649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 01/16/2024] [Indexed: 02/17/2024]
Abstract
In plants so-called plasma membrane intrinsic proteins (PIPs) are major water channels governing plant water status. Membrane trafficking contributes to functional regulation of major PIPs and is crucial for abiotic stress resilience. Arabidopsis PIP2;1 is rapidly internalised from the plasma membrane in response to high salinity to regulate osmotic water transport, but knowledge of the underlying mechanisms is fragmentary. Here we show that PIP2;1 occurs in complex with SYNTAXIN OF PLANTS 132 (SYP132) together with the plasma membrane H+ -ATPase AHA1 as evidenced through in vivo and in vitro analysis. SYP132 is a multifaceted vesicle trafficking protein, known to interact with AHA1 and promote endocytosis to impact growth and pathogen defence. Tracking native proteins in immunoblot analysis, we found that salinity stress enhances SYP132 interactions with PIP2;1 and PIP2;2 isoforms to promote redistribution of the water channels away from the plasma membrane. Concurrently, AHA1 binding within the SYP132-complex was significantly reduced under salinity stress and increased the density of AHA1 proteins at the plasma membrane in leaf tissue. Manipulating SYP132 function in Arabidopsis thaliana enhanced resilience to salinity stress and analysis in heterologous systems suggested that the SNARE influences PIP2;1 osmotic water permeability. We propose therefore that SYP132 coordinates AHA1 and PIP2;1 abundance at the plasma membrane and influences leaf hydraulics to regulate plant responses to abiotic stress signals.
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Affiliation(s)
- Guillermo Baena
- Plant Science Group, School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Bower Building, University Avenue, Glasgow, G12 8QQ, UK
| | - Lingfeng Xia
- Plant Science Group, School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Bower Building, University Avenue, Glasgow, G12 8QQ, UK
| | - Sakharam Waghmare
- Plant Science Group, School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Bower Building, University Avenue, Glasgow, G12 8QQ, UK
| | - ZhiYi Yu
- Plant Science Group, School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Bower Building, University Avenue, Glasgow, G12 8QQ, UK
| | - Yue Guo
- School of Life Science, Shanxi University, Taiyuan, Shanxi, 030006, China
| | - Michael R Blatt
- Plant Science Group, School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Bower Building, University Avenue, Glasgow, G12 8QQ, UK
| | - Ben Zhang
- School of Life Science, Shanxi University, Taiyuan, Shanxi, 030006, China
| | - Rucha Karnik
- Plant Science Group, School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Bower Building, University Avenue, Glasgow, G12 8QQ, UK
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6
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Pyrris Y, Papadaki GF, Mikros E, Diallinas G. The last two transmembrane helices in the APC-type FurE transporter act as an intramolecular chaperone essential for concentrative ER-exit. Microb Cell 2024; 11:1-15. [PMID: 38225947 PMCID: PMC10788122 DOI: 10.15698/mic2024.01.811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 10/31/2023] [Accepted: 11/13/2023] [Indexed: 01/17/2024]
Abstract
FurE is a H+ symporter specific for the cellular uptake of uric acid, allantoin, uracil, and toxic nucleobase analogues in the fungus Aspergillus nidulans. Being member of the NCS1 protein family, FurE is structurally related to the APC-superfamily of transporters. APC-type transporters are characterised by a 5+5 inverted repeat fold made of ten transmembrane segments (TMS1-10) and function through the rocking-bundle mechanism. Most APC-type transporters possess two extra C-terminal TMS segments (TMS11-12), the function of which remains elusive. Here we present a systematic mutational analysis of TMS11-12 of FurE and show that two specific aromatic residues in TMS12, Trp473 and Tyr484, are essential for ER-exit and trafficking to the plasma membrane (PM). Molecular modeling shows that Trp473 and Tyr484 might be essential through dynamic interactions with residues in TMS2 (Leu91), TMS3 (Phe111), TMS10 (Val404, Asp406) and other aromatic residues in TMS12. Genetic analysis confirms the essential role of Phe111, Asp406 and TMS12 aromatic residues in FurE ER-exit. We further show that co-expression of FurE-Y484F or FurE-W473A with wild-type FurE leads to a dominant negative phenotype, compatible with the concept that FurE molecules oligomerize or partition in specific microdomains to achieve concentrative ER-exit and traffic to the PM. Importantly, truncated FurE versions lacking TMS11-12 are unable to reproduce a negative effect on the trafficking of co-expressed wild-type FurE. Overall, we show that TMS11-12 acts as an intramolecular chaperone for proper FurE folding, which seems to provide a structural code for FurE partitioning in ER-exit sites.
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Affiliation(s)
- Yiannis Pyrris
- Department of Biology, National and Kapodistrian University of Athens, Panepistimioupolis, Athens, 15784, Greece
| | - Georgia F. Papadaki
- Department of Biology, National and Kapodistrian University of Athens, Panepistimioupolis, Athens, 15784, Greece
| | - Emmanuel Mikros
- Department of Pharmacy, National and Kapodistrian University of Athens, Panepistimioupolis, Athens, 15771, Greece
| | - George Diallinas
- Department of Biology, National and Kapodistrian University of Athens, Panepistimioupolis, Athens, 15784, Greece
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology, Heraklion, 70013, Greece
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7
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Kioumourtzoglou D, Black HL, Al Tobi M, Livingstone R, Petrie JR, Boyle JG, Gould GW, Bryant NJ. Phosphorylation of Syntaxin 4 by the Insulin Receptor Drives Exocytic SNARE Complex Formation to Deliver GLUT4 to the Cell Surface. Biomolecules 2023; 13:1738. [PMID: 38136609 PMCID: PMC10741561 DOI: 10.3390/biom13121738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 11/24/2023] [Accepted: 11/29/2023] [Indexed: 12/24/2023] Open
Abstract
A major consequence of insulin binding its receptor on fat and muscle cells is the stimulation of glucose transport into these tissues. This is achieved through an increase in the exocytic trafficking rate of the facilitative glucose transporter GLUT4 from intracellular stores to the cell surface. Delivery of GLUT4 to the cell surface requires the formation of functional SNARE complexes containing Syntaxin 4, SNAP23, and VAMP2. Insulin stimulates the formation of these complexes and concomitantly causes phosphorylation of Syntaxin 4. Here, we use a combination of biochemistry and cell biological approaches to provide a mechanistic link between these observations. We present data to support the hypothesis that Tyr-115 and Tyr-251 of Syntaxin 4 are direct substrates of activated insulin receptors, and that these residues modulate the protein's conformation and thus regulate the rate at which Syntaxin 4 forms SNARE complexes that deliver GLUT4 to the cell surface. This report provides molecular details on how the cell regulates SNARE-mediated membrane traffic in response to an external stimulus.
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Affiliation(s)
| | - Hannah L. Black
- Department of Biology, University of York, Heslington YO10 5DD, UK; (D.K.)
| | - Mohammed Al Tobi
- Institute of Molecular Cell and Systems Biology, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK; (M.A.T.)
| | - Rachel Livingstone
- Institute of Molecular Cell and Systems Biology, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK; (M.A.T.)
| | - John R. Petrie
- Institute of Cardiovascular and Medical Sciences, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - James G. Boyle
- School of Medicine, Dentistry & Nursing, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK;
| | - Gwyn W. Gould
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow G4 ORE, UK
| | - Nia J. Bryant
- Department of Biology, University of York, Heslington YO10 5DD, UK; (D.K.)
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G. Dornan L, C. Simpson J. Rab6-mediated retrograde trafficking from the Golgi: the trouble with tubules. Small GTPases 2023; 14:26-44. [PMID: 37488775 PMCID: PMC10392741 DOI: 10.1080/21541248.2023.2238330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 07/13/2023] [Accepted: 07/15/2023] [Indexed: 07/26/2023] Open
Abstract
Next year marks one-quarter of a century since the discovery of the so-called COPI-independent pathway, which operates between the Golgi apparatus and the endoplasmic reticulum (ER) in eukaryotic cells. Unlike almost all other intracellular trafficking pathways, this pathway is not regulated by the physical accumulation of multisubunit proteinaceous coat molecules, but instead by the small GTPase Rab6. What also sets it apart from other pathways is that the transport carriers themselves often take the form of tubules, rather than conventional vesicles. In this review, we assess the relevant literature that has accumulated to date, in an attempt to provide a concerted description of how this pathway is regulated. We discuss the possible cargo molecules that are carried in this pathway, and the likely mechanism of Rab6 tubule biogenesis, including how the cargo itself may play a critical role. We also provide perspective surrounding the various molecular motors of the kinesin, myosin and dynein families that have been implicated in driving Rab6-coated tubular membranes long distances through the cell prior to delivering their cargo to the ER. Finally, we also raise several important questions that require resolution, if we are to ultimately provide a comprehensive molecular description of how the COPI-independent pathway is controlled.
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Affiliation(s)
- Lucy G. Dornan
- Cell Screening Laboratory, UCD School of Biology & Environmental Science, University College Dublin, Dublin, Ireland
| | - Jeremy C. Simpson
- Cell Screening Laboratory, UCD School of Biology & Environmental Science, University College Dublin, Dublin, Ireland
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9
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Taguchi T. Membrane traffic governs the STING inflammatory signalling. J Biochem 2023; 174:483-490. [PMID: 37562849 DOI: 10.1093/jb/mvad064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Revised: 07/30/2023] [Accepted: 08/02/2023] [Indexed: 08/12/2023] Open
Abstract
The cGAS-STING innate immune pathway has recently emerged as a critical driver of inflammation in a variety of settings, such as virus infection, cellular stress and tissue damage. The pathway detects microbial and host-derived double-stranded DNA (dsDNA) in the cytosol, and triggers the production of the type I interferons through the activation of IRF3. The detailed mechanistic and biochemical understanding of the pathway has enabled the development of pharmacological agents for the treatment of chronic inflammation and cancer. STING is an endoplasmic reticulum (ER)-localized transmembrane protein. Upon emergence of cytosolic dsDNA, STING exits the ER and migrates sequentially to the Golgi, recycling endosomes and lysosomes. Importantly, the intracellular translocation of STING is essential for the activation and inactivation of the STING signalling. In this review, I summarize the recent insights into the regulators of the membrane traffic of STING and STING-associated autoinflammatory diseases.
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Affiliation(s)
- Tomohiko Taguchi
- Laboratory of Organelle Pathophysiology, Department of Integrative Life Sciences, Graduate School of Life Sciences, Tohoku University, Aobayama, Aoba-ku, Sendai, Miyagi 980-8578, Japan
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10
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Hara Y, Katsuyama T, Fukaya M, Sugawara T, Shiroshima T, Sadakata T, Osumi N, Sakagami H. ADP Ribosylation Factor 4 (Arf4) Regulates Radial Migration through N-Cadherin Trafficking during Cerebral Cortical Development. eNeuro 2023; 10:ENEURO.0125-23.2023. [PMID: 37848288 PMCID: PMC10630928 DOI: 10.1523/eneuro.0125-23.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 09/28/2023] [Accepted: 10/05/2023] [Indexed: 10/19/2023] Open
Abstract
During the development of the cerebral cortex, N-cadherin plays a crucial role in facilitating radial migration by enabling cell-to-cell adhesion between migrating neurons and radial glial fibers or Cajar-Reztius cells. ADP ribosylation factor 4 (Arf4) and Arf5, which belong to the Class II Arf small GTPase subfamily, control membrane trafficking in the endocytic and secretory pathways. However, their specific contribution to cerebral cortex development remains unclear. In this study, we sought to investigate the functional involvement of Class II Arfs in radial migration during the layer formation of the cerebral cortex using mouse embryos and pups. Our findings indicate that knock-down of Arf4, but not Arf5, resulted in the stalling of transfected neurons with disorientation of the Golgi in the upper intermediate zone (IZ) and reduction in the migration speed in both the IZ and cortical plate (CP). Migrating neurons with Arf4 knock-down exhibited cytoplasmic accumulation of N-cadherin, along with disturbed organelle morphology and distribution. Furthermore, supplementation of exogenous N-cadherin partially rescued the migration defect caused by Arf4 knock-down. In conclusion, our results suggest that Arf4 plays a crucial role in regulating radial migration via N-cadherin trafficking during cerebral cortical development.
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Affiliation(s)
- Yoshinobu Hara
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Kanagawa 252-0374, Japan
| | - Takehiko Katsuyama
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Kanagawa 252-0374, Japan
| | - Masahiro Fukaya
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Kanagawa 252-0374, Japan
| | - Takeyuki Sugawara
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Kanagawa 252-0374, Japan
| | - Tomoko Shiroshima
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Kanagawa 252-0374, Japan
| | - Tetsushi Sadakata
- Education and Research Support Center, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan
| | - Noriko Osumi
- Department of Developmental Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Miyagi 980-8575, Japan
| | - Hiroyuki Sakagami
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Kanagawa 252-0374, Japan
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11
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Zhang K, Chan V, Botelho RJ, Antonescu CN. A tail of their own: regulation of cardiolipin and phosphatidylinositol fatty acyl profile by the acyltransferase LCLAT1. Biochem Soc Trans 2023; 51:1765-1776. [PMID: 37737061 DOI: 10.1042/bst20220603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 08/17/2023] [Accepted: 09/07/2023] [Indexed: 09/23/2023]
Abstract
Cardiolipin and phosphatidylinositol along with the latter's phosphorylated derivative phosphoinositides, control a wide range of cellular functions from signal transduction, membrane traffic, mitochondrial function, cytoskeletal dynamics, and cell metabolism. An emerging dimension to these lipids is the specificity of their fatty acyl chains that is remarkably distinct from that of other glycerophospholipids. Cardiolipin and phosphatidylinositol undergo acyl remodeling involving the sequential actions of phospholipase A to hydrolyze acyl chains and key acyltransferases that re-acylate with specific acyl groups. LCLAT1 (also known as LYCAT, AGPAT8, LPLAT6, or ALCAT1) is an acyltransferase that contributes to specific acyl profiles for phosphatidylinositol, phosphoinositides, and cardiolipin. As such, perturbations of LCLAT1 lead to alterations in cardiolipin-dependent phenomena such as mitochondrial respiration and dynamics and phosphoinositide-dependent processes such as endocytic membrane traffic and receptor signaling. Here we examine the biochemical and cellular actions of LCLAT1, as well as the contribution of this acyltransferase to the development and specific diseases.
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Affiliation(s)
- Kai Zhang
- Department of Chemistry and Biology, Toronto Metropolitan University, Toronto, Ontario, Canada M5B 2K3
| | - Victoria Chan
- Department of Chemistry and Biology, Toronto Metropolitan University, Toronto, Ontario, Canada M5B 2K3
- Graduate Program in Molecular Science, Toronto Metropolitan University, Toronto, Ontario, Canada M5B 2K3
| | - Roberto J Botelho
- Department of Chemistry and Biology, Toronto Metropolitan University, Toronto, Ontario, Canada M5B 2K3
- Graduate Program in Molecular Science, Toronto Metropolitan University, Toronto, Ontario, Canada M5B 2K3
| | - Costin N Antonescu
- Department of Chemistry and Biology, Toronto Metropolitan University, Toronto, Ontario, Canada M5B 2K3
- Graduate Program in Molecular Science, Toronto Metropolitan University, Toronto, Ontario, Canada M5B 2K3
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12
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Suber Y, Alam MNA, Nakos K, Bhakt P, Spiliotis ET. Microtubule-associated septin complexes modulate kinesin and dynein motility with differential specificities. J Biol Chem 2023; 299:105084. [PMID: 37495111 PMCID: PMC10463263 DOI: 10.1016/j.jbc.2023.105084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Revised: 06/27/2023] [Accepted: 07/14/2023] [Indexed: 07/28/2023] Open
Abstract
Long-range membrane traffic is guided by microtubule-associated proteins and posttranslational modifications, which collectively comprise a traffic code. The regulatory principles of this code and how it orchestrates the motility of kinesin and dynein motors are largely unknown. Septins are a large family of GTP-binding proteins, which assemble into complexes that associate with microtubules. Using single-molecule in vitro motility assays, we tested how the microtubule-associated SEPT2/6/7, SEPT2/6/7/9, and SEPT5/7/11 complexes affect the motilities of the constitutively active kinesins KIF5C and KIF1A and the dynein-dynactin-bicaudal D (DDB) motor complex. We found that microtubule-associated SEPT2/6/7 is a potent inhibitor of DDB and KIF5C, preventing mainly their association with microtubules. SEPT2/6/7 also inhibits KIF1A by obstructing stepping along microtubules. On SEPT2/6/7/9-coated microtubules, KIF1A inhibition is dampened by SEPT9, which alone enhances KIF1A, showing that individual septin subunits determine the regulatory properties of septin complexes. Strikingly, SEPT5/7/11 differs from SEPT2/6/7, in permitting the motility of KIF1A and immobilizing DDB to the microtubule lattice. In hippocampal neurons, filamentous SEPT5 colocalizes with somatodendritic microtubules that underlie Golgi membranes and lack SEPT6. Depletion of SEPT5 disrupts Golgi morphology and polarization of Golgi ribbons into the shaft of somato-proximal dendrites, which is consistent with the tethering of DDB to microtubules by SEPT5/7/11. Collectively, these results suggest that microtubule-associated complexes have differential specificities in the regulation of the motility and positioning of microtubule motors. We posit that septins are an integral part of the microtubule-based code that spatially controls membrane traffic.
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Affiliation(s)
- Yani Suber
- Department of Biology, Drexel University, Philadelphia, Pennsylvania, USA
| | - Md Noor A Alam
- Department of Biology, Drexel University, Philadelphia, Pennsylvania, USA
| | - Konstantinos Nakos
- Department of Biology, Drexel University, Philadelphia, Pennsylvania, USA
| | - Priyanka Bhakt
- Department of Biology, Drexel University, Philadelphia, Pennsylvania, USA
| | - Elias T Spiliotis
- Department of Biology, Drexel University, Philadelphia, Pennsylvania, USA.
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13
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Toshima JY, Tsukahara A, Nagano M, Tojima T, Siekhaus DE, Nakano A, Toshima J. The yeast endocytic early/sorting compartment exists as an independent sub-compartment within the trans-Golgi network. eLife 2023; 12:e84850. [PMID: 37477116 PMCID: PMC10361720 DOI: 10.7554/elife.84850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 07/08/2023] [Indexed: 07/22/2023] Open
Abstract
Although budding yeast has been extensively used as a model organism for studying organelle functions and intracellular vesicle trafficking, whether it possesses an independent endocytic early/sorting compartment that sorts endocytic cargos to the endo-lysosomal pathway or the recycling pathway has long been unclear. The structure and properties of the endocytic early/sorting compartment differ significantly between organisms; in plant cells, the trans-Golgi network (TGN) serves this role, whereas in mammalian cells a separate intracellular structure performs this function. The yeast syntaxin homolog Tlg2p, widely localizing to the TGN and endosomal compartments, is presumed to act as a Q-SNARE for endocytic vesicles, but which compartment is the direct target for endocytic vesicles remained unanswered. Here we demonstrate by high-speed and high-resolution 4D imaging of fluorescently labeled endocytic cargos that the Tlg2p-residing compartment within the TGN functions as the early/sorting compartment. After arriving here, endocytic cargos are recycled to the plasma membrane or transported to the yeast Rab5-residing endosomal compartment through the pathway requiring the clathrin adaptors GGAs. Interestingly, Gga2p predominantly localizes at the Tlg2p-residing compartment, and the deletion of GGAs has little effect on another TGN region where Sec7p is present but suppresses dynamics of the Tlg2-residing early/sorting compartment, indicating that the Tlg2p- and Sec7p-residing regions are discrete entities in the mutant. Thus, the Tlg2p-residing region seems to serve as an early/sorting compartment and function independently of the Sec7p-residing region within the TGN.
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Affiliation(s)
- Junko Y Toshima
- School of Health Science, Tokyo University of Technology, Tokyo, Japan
- Department of Biological Science and Technology, Tokyo University of Science, Tokyo, Japan
| | - Ayana Tsukahara
- Department of Biological Science and Technology, Tokyo University of Science, Tokyo, Japan
| | - Makoto Nagano
- Department of Biological Science and Technology, Tokyo University of Science, Tokyo, Japan
| | - Takuro Tojima
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, Saitama, Japan
| | - Daria E Siekhaus
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Akihiko Nakano
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, Saitama, Japan
| | - Jiro Toshima
- Department of Biological Science and Technology, Tokyo University of Science, Tokyo, Japan
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14
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Inoue R, Fukutani Y, Niwa T, Matsunami H, Yohda M. Identification and Characterization of Proteins That Are Involved in RTP1S-Dependent Transport of Olfactory Receptors. Int J Mol Sci 2023; 24:ijms24097829. [PMID: 37175532 PMCID: PMC10177996 DOI: 10.3390/ijms24097829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 04/17/2023] [Accepted: 04/21/2023] [Indexed: 05/15/2023] Open
Abstract
Olfaction is mediated via olfactory receptors (ORs) that are expressed on the cilia membrane of olfactory sensory neurons in the olfactory epithelium. The functional expression of most ORs requires the assistance of receptor-transporting proteins (RTPs). We examined the interactome of RTP1S and OR via proximity biotinylation. Deubiquitinating protein VCIP135, the F-actin-capping protein sub-unit alpha-2, and insulin-like growth factor 2 mRNA-binding protein 2 were biotinylated via AirID fused with OR, RTP1S-AirID biotinylated heat shock protein A6 (HSPA6), and double-stranded RNA-binding protein Staufen homolog 2 (STAU2). Co-expression of HSPA6 partially enhanced the surface expression of Olfr544. The surface expression of Olfr544 increased by 50-80%. This effect was also observed when RTP1S was co-expressed. Almost identical results were obtained from the co-expression of STAU2. The interactions of HSPA6 and STAU2 with RTP1S were examined using a NanoBit assay. The results show that the RTP1S N-terminus interacted with the C-terminal domain of HSP6A and the N-terminal domain of STAU2. In contrast, OR did not significantly interact with STAU2 and HSPA6. Thus, HSP6A and STAU2 appear to be involved in the process of OR traffic through interaction with RTP1S.
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Affiliation(s)
- Ryosuke Inoue
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Yosuke Fukutani
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Tatsuya Niwa
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama 226-8503, Japan
| | - Hiroaki Matsunami
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Masafumi Yohda
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
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15
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Asadi P, Milev MP, Saint-Dic D, Gamberi C, Sacher M. Vitamin B5, a coenzyme A precursor, rescues TANGO2 deficiency disease-associated defects in Drosophila and human cells. J Inherit Metab Dis 2023; 46:358-368. [PMID: 36502486 PMCID: PMC10464931 DOI: 10.1002/jimd.12579] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 11/22/2022] [Accepted: 12/07/2022] [Indexed: 12/14/2022]
Abstract
Mutations in the Transport and Golgi Organization 2 (TANGO2) gene are associated with intellectual deficit, neurodevelopmental delay and regression. Individuals can also present with an acute metabolic crisis that includes rhabdomyolysis, cardiomyopathy, and cardiac arrhythmias, the latter of which are potentially lethal. While preventing metabolic crises has the potential to reduce mortality, no treatments currently exist for this condition. The function of TANGO2 remains unknown but is suspected to be involved in some aspect of lipid metabolism. Here, we describe a model of TANGO2-related disease in the fruit fly Drosophila melanogaster that recapitulates crucial disease traits. Pairing a new fly model with human cells, we examined the effects of vitamin B5, a coenzyme A (CoA) precursor, on alleviating the cellular and organismal defects associated with TANGO2 deficiency. We demonstrate that vitamin B5 specifically improves multiple defects associated with TANGO2 loss-of-function in Drosophila and rescues membrane trafficking defects in human cells. We also observed a partial rescue of one of the fly defects by vitamin B3, though to a lesser extent than vitamin B5. Our data suggest that a B complex supplement containing vitamin B5/pantothenate may have therapeutic benefits in individuals with TANGO2-deficiency disease. Possible mechanisms for the rescue are discussed that may include restoration of lipid homeostasis.
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Affiliation(s)
- Paria Asadi
- Concordia University, Department of Biology, Montreal, Quebec, Canada, H4B1R6
| | - Miroslav P. Milev
- Concordia University, Department of Biology, Montreal, Quebec, Canada, H4B1R6
| | - Djenann Saint-Dic
- Concordia University, Department of Biology, Montreal, Quebec, Canada, H4B1R6
| | - Chiara Gamberi
- Coastal Carolina University, Department of Biology, Conway, South Carolina, USA, 29526
| | - Michael Sacher
- Concordia University, Department of Biology, Montreal, Quebec, Canada, H4B1R6
- McGill University, Department of Anatomy and Cell Biology, Montreal, Quebec, Canada, H3A0C7
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16
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Zhozhikov L, Sukhomyasova A, Gurinova E, Nogovicina A, Vasilev F, Maksimova N. Origins of SOPH syndrome: A study of 93 Yakut patients with review of C-terminal phenotype. Clin Genet 2023; 103:625-635. [PMID: 36843433 DOI: 10.1111/cge.14319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 02/21/2023] [Accepted: 02/22/2023] [Indexed: 02/28/2023]
Abstract
Since the first report of SOPH syndrome among the Yakut population in 2010, new clinical data of SOPH-like conditions continue to appear. We expand the phenotypic spectrum of SOPH syndrome and perform a comparative analysis of Yakut SOPH patients' clinical data with SOPH-like conditions reported in the world scientific literature to form a foundation for NBAS pathogenesis discussion. Clinical data from the genetic records of 93 patients with SOPH syndrome and global survey data on patients with pathogenic variants of the C-terminal in the NBAS gene were collected. A detailed phenotype description of patients is presented with a total number of 111 individuals. Underweight below the fifth centile and prone to delayed bone age in Yakut SOPH patients are retrospectively observed. We outline the short stature with optic atrophy as the leading phenotyping trait for C-terminal NBAS patients. The pathophysiology and patients management of SOPH-like conditions are discussed.
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Affiliation(s)
- Leonid Zhozhikov
- Research Laboratory of "Molecular Medicine and Human Genetics", Institute of Medicine, North-Eastern Federal University, Yakutsk, Russia
| | - Aitalina Sukhomyasova
- Research Laboratory of "Molecular Medicine and Human Genetics", Institute of Medicine, North-Eastern Federal University, Yakutsk, Russia
- Medical Genetic Center, Republic Hospital No1 - National Center of Medicine, Yakutsk, Russia
| | - Elizaveta Gurinova
- Medical Genetic Center, Republic Hospital No1 - National Center of Medicine, Yakutsk, Russia
| | - Anna Nogovicina
- Research Laboratory of "Molecular Medicine and Human Genetics", Institute of Medicine, North-Eastern Federal University, Yakutsk, Russia
| | - Filipp Vasilev
- Research Laboratory of "Molecular Medicine and Human Genetics", Institute of Medicine, North-Eastern Federal University, Yakutsk, Russia
| | - Nadezhda Maksimova
- Research Laboratory of "Molecular Medicine and Human Genetics", Institute of Medicine, North-Eastern Federal University, Yakutsk, Russia
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17
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Gopaldass N, De Leo MG, Courtellemont T, Mercier V, Bissig C, Roux A, Mayer A. Retromer oligomerization drives SNX-BAR coat assembly and membrane constriction. EMBO J 2023; 42:e112287. [PMID: 36644906 PMCID: PMC9841331 DOI: 10.15252/embj.2022112287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 11/02/2022] [Accepted: 11/02/2022] [Indexed: 01/17/2023] Open
Abstract
Proteins exit from endosomes through tubular carriers coated by retromer, a complex that impacts cellular signaling, lysosomal biogenesis and numerous diseases. The coat must overcome membrane tension to form tubules. We explored the dynamics and driving force of this process by reconstituting coat formation with yeast retromer and the BAR-domain sorting nexins Vps5 and Vps17 on oriented synthetic lipid tubules. This coat oligomerizes bidirectionally, forming a static tubular structure that does not exchange subunits. High concentrations of sorting nexins alone constrict membrane tubes to an invariant radius of 19 nm. At lower concentrations, oligomers of retromer must bind and interconnect the sorting nexins to drive constriction. Constricting less curved membranes into tubes, which requires more energy, coincides with an increased surface density of retromer on the sorting nexin layer. Retromer-mediated crosslinking of sorting nexins at variable densities may thus tune the energy that the coat can generate to deform the membrane. In line with this, genetic ablation of retromer oligomerization impairs endosomal protein exit in yeast and human cells.
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Affiliation(s)
- Navin Gopaldass
- Department of ImmunobiologyUniversity of LausanneEpalingesSwitzerland
| | | | | | - Vincent Mercier
- Department of BiochemistryUniversity of GenevaGenevaSwitzerland
| | - Christin Bissig
- Department of ImmunobiologyUniversity of LausanneEpalingesSwitzerland
| | - Aurélien Roux
- Department of BiochemistryUniversity of GenevaGenevaSwitzerland
- Swiss National Centre for Competence in Research Program Chemical BiologyGenevaSwitzerland
| | - Andreas Mayer
- Department of ImmunobiologyUniversity of LausanneEpalingesSwitzerland
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18
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Ito Y, Uemura T. Super resolution live imaging: The key for unveiling the true dynamics of membrane traffic around the Golgi apparatus in plant cells. Front Plant Sci 2022; 13:1100757. [PMID: 36618665 PMCID: PMC9818705 DOI: 10.3389/fpls.2022.1100757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 12/12/2022] [Indexed: 06/17/2023]
Abstract
In contrast to the relatively static image of the plants, the world inside each cell is surprisingly dynamic. Membrane-bounded organelles move actively on the cytoskeletons and exchange materials by vesicles, tubules, or direct contact between each other. In order to understand what is happening during those events, it is essential to visualize the working components in vivo. After the breakthrough made by the application of fluorescent proteins, the development of light microscopy enabled many discoveries in cell biology, including those about the membrane traffic in plant cells. Especially, super-resolution microscopy, which is becoming more and more accessible, is now one of the most powerful techniques. However, although the spatial resolution has improved a lot, there are still some difficulties in terms of the temporal resolution, which is also a crucial parameter for the visualization of the living nature of the intracellular structures. In this review, we will introduce the super resolution microscopy developed especially for live-cell imaging with high temporal resolution, and show some examples that were made by this tool in plant membrane research.
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Affiliation(s)
- Yoko Ito
- Institute for Human Life Science, Ochanomizu University, Tokyo, Japan
| | - Tomohiro Uemura
- Graduate School of Humanities and Sciences, Ochanomizu University, Tokyo, Japan
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19
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Abstract
The plasma membrane of eukaryotic cells is composed of a large number of lipid species that are laterally segregated into functional domains as well as asymmetrically distributed between the outer and inner leaflets. Additionally, the spatial distribution and organization of these lipids dramatically change in response to various cellular states, such as cell division, differentiation, and apoptosis. Division of one cell into two daughter cells is one of the most fundamental requirements for the sustenance of growth in all living organisms. The successful completion of cytokinesis, the final stage of cell division, is critically dependent on the spatial distribution and organization of specific lipids. In this review, we discuss the properties of various lipid species associated with cytokinesis and the mechanisms involved in their polarization, including forward trafficking, endocytic recycling, local synthesis, and cortical flow models. The differences in lipid species requirements and distribution in mitotic vs. male meiotic cells will be discussed. We will concentrate on sphingolipids and phosphatidylinositols because their transbilayer organization and movement may be linked via the cytoskeleton and thus critically regulate various steps of cytokinesis.
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20
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Beyers WC, Detry AM, Di Pietro SM. OCA7 is a melanosome membrane protein that defines pigmentation by regulating early stages of melanosome biogenesis. J Biol Chem 2022; 298:102669. [PMID: 36334630 DOI: 10.1016/j.jbc.2022.102669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 10/21/2022] [Accepted: 10/24/2022] [Indexed: 11/11/2022] Open
Abstract
Mutations in C10orf11 (oculocutaneous albinism type 7 [OCA7]) cause OCA, a disorder that presents with hypopigmentation in skin, eyes, and hair. The OCA7 pathophysiology is unknown, and there is virtually no information on the OCA7 protein and its cellular function. Here, we discover that OCA7 localizes to the limiting membrane of melanosomes, the specialized pigment cell organelles where melanin is synthesized. We demonstrate that OCA7 is recruited through interaction with a canonical effector-binding surface of melanosome proteins Rab32 and Rab38. Using newly generated OCA7-KO MNT1 cells, we show OCA7 regulates overall melanin levels in a melanocyte autonomous manner by controlling melanosome maturation. Importantly, we found that OCA7 regulates premelanosome protein (PMEL) processing, impacting fibrillation and the striations that define transition from melanosome stage I to stage II. Furthermore, the melanosome lumen of OCA7-KO cells displays lower pH than control cells. Together, our results reveal that OCA7 regulates pigmentation through two well-established determinants of melanosome biogenesis and function, PMEL processing, and organelle pH.
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Affiliation(s)
- Wyatt C Beyers
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado, USA
| | - Anna M Detry
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado, USA
| | - Santiago M Di Pietro
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado, USA.
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21
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Nishizawa A, Maruta Y, Fukuda M. Rab32/38-Dependent and -Independent Transport of Tyrosinase to Melanosomes in B16-F1 Melanoma Cells. Int J Mol Sci 2022; 23. [PMID: 36430618 DOI: 10.3390/ijms232214144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Revised: 11/11/2022] [Accepted: 11/14/2022] [Indexed: 11/19/2022] Open
Abstract
B16-F1 melanoma cells have often been used as a model to investigate melanogenesis, but the evidence that melanosome biogenesis and transport occur by the same mechanisms in normal melanocytes and B16-F1 cells is insufficient. In this study, we established knockout B16-F1 cells for each of several key factors in melanogenesis, i.e., tyrosinase (Tyr), Hps4, Rab27A, and Rab32·Rab38 (Rab32/38), and then compared their phenotypes with the phenotypes of corresponding mutant mouse melanocyte cell lines, i.e., melan-c, melan-le, melan-ash, and Rab32-deficient melan-cht cells, respectively. The results showed that Tyr and Rab27A are also indispensable for melanin synthesis and peripheral melanosome distribution, respectively, in B16-F1 cells, but that Hps4 or its downstream targets Rab32/38 are not essential for Tyr transport in B16-F1 cells, suggesting the existence of a Rab32/38-independent Tyr transport mechanism in B16-F1 cells. We then performed comprehensive knockdown screening of Rab small GTPases and identified Rab10 and Rab24, previously uncharacterized Rabs in melanocytes, as being involved in Tyr transport under Rab32/38-null conditions. Our findings indicate a difference between the Tyr transport mechanism in melanocytes and B16-F1 cells in terms of Rab32/38-dependency and a limitation in regard to using melanoma cells as a model for melanocytes, especially when investigating the mechanism of endosomal Tyr transport.
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22
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Shindo R, Kuchitsu Y, Mukai K, Taguchi T. The activity of disease-causative STING variants can be suppressed by wild-type STING through heterocomplex formation. Front Cell Dev Biol 2022; 10:1037999. [PMID: 36438571 PMCID: PMC9682468 DOI: 10.3389/fcell.2022.1037999] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 10/24/2022] [Indexed: 12/21/2023] Open
Abstract
Stimulator of interferon genes (STING) is essential for the type I interferon response induced by microbial DNA from viruses or self-DNA from mitochondria/nuclei. Recently, gain-of-function mutations in STING have been identified in patients with STING-associated vasculopathy with onset in infancy (SAVI). The SAVI patients exhibit complex systemic vascular inflammation and interstitial lung disease, resulting in pulmonary fibrosis and respiratory failure. SAVI mouse models have recently developed, harbouring common SAVI mutations, such as N153S and V154M, which correspond to the human N154S and V155M, respectively. Interestingly, crosses of heterozygous SAVI mice did not yield homozygous SAVI mice as of embryonic day 14, indicating that homozygous SAVI embryos were not viable and that wild-type (WT) allele would function dominantly over SAVI alleles in terms of viability. However, the molecular mechanism underlying the dominance has not been understood. In the present study, we show that STING (WT) and STING (SAVI) can form heterocomplex. The heterocomplex localized primarily in the endoplasmic reticulum (ER) and failed to reach the trans-Golgi network (TGN), where STING activates the downstream kinase TBK1. SURF4 is the essential protein functioning in the retrieval of STING from the Golgi to the ER. The amount of SURF4 bound to STING (SAVI) significantly increased in the presence of STING (WT). These results suggest that STING (WT) can suppress the activity of STING (SAVI) by tethering STING (SAVI) to the ER through heterocomplex formation. The dormant heterocomplex formation may underlie, at least in part, the dominance of STING WT allele over SAVI alleles in the STING-triggered inflammatory response.
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Affiliation(s)
| | | | - Kojiro Mukai
- Laboratory of Organelle Pathophysiology, Department of Integrative Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Tomohiko Taguchi
- Laboratory of Organelle Pathophysiology, Department of Integrative Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Japan
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23
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Arneaud SLB, McClendon J, Tatge L, Watterson A, Zuurbier KR, Madhu B, Gumienny TL, Douglas PM. Reduced bone morphogenic protein signaling along the gut-neuron axis by heat shock factor promotes longevity. Aging Cell 2022; 21:e13693. [PMID: 35977034 PMCID: PMC9470895 DOI: 10.1111/acel.13693] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 06/24/2022] [Accepted: 07/27/2022] [Indexed: 01/25/2023] Open
Abstract
Aging is a complex and highly regulated process of interwoven signaling mechanisms. As an ancient transcriptional regulator of thermal adaptation and protein homeostasis, the Heat Shock Factor, HSF-1, has evolved functions within the nervous system to control age progression; however, the molecular details and signaling dynamics by which HSF-1 modulates age across tissues remain unclear. Herein, we report a nonautonomous mode of age regulation by HSF-1 in the Caenorhabditis elegans nervous system that works through the bone morphogenic protein, BMP, signaling pathway to modulate membrane trafficking in peripheral tissues. In particular, HSF-1 represses the expression of the neuron-specific BMP ligand, DBL-1, and initiates a complementary negative feedback loop within the intestine. By reducing receipt of DBL-1 in the periphery, the SMAD transcriptional coactivator, SMA-3, represses the expression of critical membrane trafficking regulators including Rab GTPases involved in early (RAB-5), late (RAB-7), and recycling (RAB-11.1) endosomal dynamics and the BMP receptor binding protein, SMA-10. This reduces cell surface residency and steady-state levels of the type I BMP receptor, SMA-6, in the intestine and further dampens signal transmission to the periphery. Thus, the ability of HSF-1 to coordinate BMP signaling along the gut-brain axis is an important determinate in age progression.
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Affiliation(s)
| | - Jacob McClendon
- Department of Molecular BiologyUT Southwestern Medical CenterDallasTexasUSA
| | - Lexus Tatge
- Department of Molecular BiologyUT Southwestern Medical CenterDallasTexasUSA
| | - Abigail Watterson
- Department of Molecular BiologyUT Southwestern Medical CenterDallasTexasUSA
| | - Kielen R. Zuurbier
- Department of Molecular BiologyUT Southwestern Medical CenterDallasTexasUSA
| | - Bhoomi Madhu
- Department of BiologyTexas Woman's UniversityDentonTexasUSA
| | | | - Peter M. Douglas
- Department of Molecular BiologyUT Southwestern Medical CenterDallasTexasUSA,Hamon Center for Regenerative Science and MedicineUT Southwestern Medical CenterDallasTexasUSA
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24
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Gomez-Navarro N, Maldutyte J, Poljak K, Peak-Chew SY, Orme J, Bisnett BJ, Lamb CH, Boyce M, Gianni D, Miller EA. Selective inhibition of protein secretion by abrogating receptor-coat interactions during ER export. Proc Natl Acad Sci U S A 2022; 119:e2202080119. [PMID: 35901214 PMCID: PMC9351455 DOI: 10.1073/pnas.2202080119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 06/01/2022] [Indexed: 01/03/2023] Open
Abstract
Protein secretion is an essential process that drives cell growth, movement, and communication. Protein traffic within the secretory pathway occurs via transport intermediates that bud from one compartment and fuse with a downstream compartment to deliver their contents. Here, we explore the possibility that protein secretion can be selectively inhibited by perturbing protein-protein interactions that drive capture into transport vesicles. Human proprotein convertase subtilisin/kexin type 9 (PCSK9) is a determinant of cholesterol metabolism whose secretion is mediated by a specific cargo adaptor protein, SEC24A. We map a series of protein-protein interactions between PCSK9, its endoplasmic reticulum (ER) export receptor SURF4, and SEC24A that mediate secretion of PCSK9. We show that the interaction between SURF4 and SEC24A can be inhibited by 4-phenylbutyrate (4-PBA), a small molecule that occludes a cargo-binding domain of SEC24. This inhibition reduces secretion of PCSK9 and additional SURF4 clients that we identify by mass spectrometry, leaving other secreted cargoes unaffected. We propose that selective small-molecule inhibition of cargo recognition by SEC24 is a potential therapeutic intervention for atherosclerosis and other diseases that are modulated by secreted proteins.
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Affiliation(s)
- Natalia Gomez-Navarro
- Cell Biology Division, Medical Research Council Laboratory of Molecular Biology, Cambridge, CB2 0QH, United Kingdom
| | - Julija Maldutyte
- Cell Biology Division, Medical Research Council Laboratory of Molecular Biology, Cambridge, CB2 0QH, United Kingdom
| | - Kristina Poljak
- Cell Biology Division, Medical Research Council Laboratory of Molecular Biology, Cambridge, CB2 0QH, United Kingdom
| | - Sew-Yeu Peak-Chew
- Cell Biology Division, Medical Research Council Laboratory of Molecular Biology, Cambridge, CB2 0QH, United Kingdom
| | - Jonathon Orme
- Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, CB2 0AA, United Kingdom
| | - Brittany J. Bisnett
- Department of Biochemistry, Duke University School of Medicine, Durham, NC27710, USA
| | - Caitlin H. Lamb
- Department of Biochemistry, Duke University School of Medicine, Durham, NC27710, USA
| | - Michael Boyce
- Department of Biochemistry, Duke University School of Medicine, Durham, NC27710, USA
| | - Davide Gianni
- Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, CB2 0AA, United Kingdom
| | - Elizabeth A. Miller
- Cell Biology Division, Medical Research Council Laboratory of Molecular Biology, Cambridge, CB2 0QH, United Kingdom
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25
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Wang Y, Karnik R, Garcia-Mata C, Hu H. Editorial: Transport and Membrane Traffic in Stomatal Biology. Front Plant Sci 2022; 13:898128. [PMID: 35712596 PMCID: PMC9197599 DOI: 10.3389/fpls.2022.898128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 03/24/2022] [Indexed: 06/15/2023]
Affiliation(s)
- Yizhou Wang
- College of Agriculture and Biotechnology, Institute of Crop Science, Zhejiang University, Hangzhou, China
| | - Rucha Karnik
- Laboratory of Plant Physiology and Biophysics, Plant Science Group, Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, United Kingdom
| | - Carlos Garcia-Mata
- Instituto de Investigaciones Biológicas, CONICET-Universidad Nacional de Mar del Plata, Mar del Plata, Argentina
| | - Honghong Hu
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
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26
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Matsui T, Sakamaki Y, Nakashima S, Fukuda M. Rab39 and its effector UACA regulate basolateral exosome release from polarized epithelial cells. Cell Rep 2022; 39:110875. [PMID: 35649370 DOI: 10.1016/j.celrep.2022.110875] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 03/29/2022] [Accepted: 05/05/2022] [Indexed: 11/25/2022] Open
Abstract
Exosomes are small extracellular vesicles that originate from the intraluminal vesicles of multivesicular bodies (MVBs). We previously reported that polarized Madin-Darby canine kidney (MDCK) epithelial cells secrete two types of exosomes, apical and basolateral exosomes, from different MVBs. However, how these MVBs are selectively targeted to the apical or basolateral membrane remained unknown. Here, we analyze members of the Rab family small GTPases and show that different sets of Rabs mediate asymmetrical exosome release. Rab27, the best-known regulator of MVB transport for exosome release, is specifically but partially involved in apical exosome release, and Rab37, a close homolog of Rab27, is an additional apical exosome regulator. By contrast, Rab39 functions as a specific regulator of basolateral exosome release. Mechanistically, Rab39 interacts with its effector UACA, and UACA then recruits Lyspersin, a component of BLOC-1-related complex (BORC). Our findings suggest that the Rab39-UACA-BORC complex specifically mediates basolateral exosome release.
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Affiliation(s)
- Takahide Matsui
- Laboratory of Membrane Trafficking Mechanisms, Department of Integrative Life Sciences, Graduate School of Life Sciences, Tohoku University, Aobayama, Aoba-ku, Sendai, Miyagi 980-8578, Japan.
| | - Yuriko Sakamaki
- Microscopy Research Support Unit Research Core, Tokyo Medical and Dental University, Tokyo 113-8510, Japan
| | - Shumpei Nakashima
- Laboratory of Membrane Trafficking Mechanisms, Department of Integrative Life Sciences, Graduate School of Life Sciences, Tohoku University, Aobayama, Aoba-ku, Sendai, Miyagi 980-8578, Japan
| | - Mitsunori Fukuda
- Laboratory of Membrane Trafficking Mechanisms, Department of Integrative Life Sciences, Graduate School of Life Sciences, Tohoku University, Aobayama, Aoba-ku, Sendai, Miyagi 980-8578, Japan.
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27
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Kemmoku H, Kuchitsu Y, Mukai K, Taguchi T. Specific association of TBK1 with the trans-Golgi network following STING stimulation. Cell Struct Funct 2022; 47:19-30. [PMID: 35125375 PMCID: PMC10511044 DOI: 10.1247/csf.21080] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Accepted: 01/30/2022] [Indexed: 12/17/2023] Open
Abstract
Stimulator of interferon genes (STING) is essential for the type I interferon response induced by microbial DNA or self-DNA leaked from mitochondria/nuclei. In response to the emergence of such DNAs in the cytosol, STING relocates from the endoplasmic reticulum (ER) to the Golgi, and activates TANK-binding kinase 1 (TBK1), a cytosolic kinase essential for the activation of STING-dependent downstream signalling. To understand at which subcellular compartments TBK1 becomes associated with STING, we generated cells stably expressing fluorescent protein-tagged STING (mNeonGreen-STING) and TBK1 (TBK1-mScarletI). We found that after STING stimulation, TBK1 became associated with the trans-Golgi network (TGN), not the other parts of the Golgi. STING variants that constitutively induce the type I interferon response have been identified in patients with autoinflammatory diseases named "STING-associated vasculopathy with onset in infancy (SAVI)". Even in cells expressing these constitutively active STING variants, TBK1 was found to be associated with TGN, not the other parts of the Golgi. These results suggest that TGN acts as a specific platform where STING associates with and activates TBK1.Key words: the Golgi, membrane traffic, innate immunity, STING.
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Affiliation(s)
- Haruka Kemmoku
- Laboratory of Organelle Pathophysiology, Department of Integrative Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Yoshihiko Kuchitsu
- Laboratory of Organelle Pathophysiology, Department of Integrative Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Kojiro Mukai
- Laboratory of Organelle Pathophysiology, Department of Integrative Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Tomohiko Taguchi
- Laboratory of Organelle Pathophysiology, Department of Integrative Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Japan
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28
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Artykov AA, Yagolovich AV, Dolgikh DA, Kirpichnikov MP, Trushina DB, Gasparian ME. Corrigendum: Death Receptors DR4 and DR5 Undergo Spontaneous and Ligand-Mediated Endocytosis and Recycling Regardless of the Sensitivity of Cancer Cells to TRAIL. Front Cell Dev Biol 2022; 9:820069. [PMID: 35237612 PMCID: PMC8883345 DOI: 10.3389/fcell.2021.820069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 11/24/2021] [Indexed: 11/13/2022] Open
Affiliation(s)
- Artem A Artykov
- Department of Bioengineering, Institute of Bioorganic Chemistry (RAS), Moscow, Russia
| | - Anne V Yagolovich
- Department of Bioengineering, Institute of Bioorganic Chemistry (RAS), Moscow, Russia.,Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Dmitry A Dolgikh
- Department of Bioengineering, Institute of Bioorganic Chemistry (RAS), Moscow, Russia.,Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Mikhail P Kirpichnikov
- Department of Bioengineering, Institute of Bioorganic Chemistry (RAS), Moscow, Russia.,Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Daria B Trushina
- Department of X-Ray and Synchrotron Research, A.V. Shubnikov Institute of Crystallography of Federal Scientific Research Centre "Crystallography and Photonics" of Russian Academy of Sciences, Moscow, Russia
| | - Marine E Gasparian
- Department of Bioengineering, Institute of Bioorganic Chemistry (RAS), Moscow, Russia
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29
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Abstract
Insulin rapidly stimulates GLUT4 translocation and glucose transport in fat and muscle cells. Signals from the occupied insulin receptor are translated into downstream signalling changes in serine/threonine kinases within timescales of seconds, and this is followed by delivery and accumulation of the glucose transporter GLUT4 at the plasma membrane. Kinetic studies have led to realisation that there are distinct phases of this stimulation by insulin. There is a rapid initial burst of GLUT4 delivered to the cell surface from a subcellular reservoir compartment and this is followed by a steady-state level of continuing stimulation in which GLUT4 recycles through a large itinerary of subcellular locations. Here, we provide an overview of the phases of insulin stimulation of GLUT4 translocation and the molecules that are currently considered to activate these trafficking steps. Furthermore, we suggest how use of new experimental approaches together with phospho-proteomic data may help to further identify mechanisms for activation of these trafficking processes.
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Affiliation(s)
- Daniel J Fazakerley
- Metabolic Research Laboratories, Wellcome-Medical Research Council Institute of Metabolic Science, University of Cambridge, Cambridge CB2 0QQ, U.K
| | - Francoise Koumanov
- Department for Health, Centre for Nutrition, Exercise, and Metabolism, University of Bath, Bath, Somerset BA2 7AY, U.K
| | - Geoffrey D Holman
- Department of Biology and Biochemistry, University of Bath, Bath, Somerset BA2 7AY, U.K
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30
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Hasegawa J, Uchida Y, Mukai K, Lee S, Matsudaira T, Taguchi T. A Role of Phosphatidylserine in the Function of Recycling Endosomes. Front Cell Dev Biol 2022; 9:783857. [PMID: 35004683 PMCID: PMC8740049 DOI: 10.3389/fcell.2021.783857] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 11/29/2021] [Indexed: 11/13/2022] Open
Abstract
Cells internalize proteins and lipids in the plasma membrane (PM) and solutes in the extracellular space by endocytosis. The removal of PM by endocytosis is constantly balanced by the replenishment of proteins and lipids to PM through recycling pathway. Recycling endosomes (REs) are specific subsets of endosomes. Besides the established role of REs in recycling pathway, recent studies have revealed unanticipated roles of REs in membrane traffic and cell signalling. In this review, we highlight these emerging issues, with a particular focus on phosphatidylserine (PS), a phospholipid that is highly enriched in the cytosolic leaflet of RE membranes. We also discuss the pathogenesis of Hermansky Pudlak syndrome type 2 (HPS2) that arises from mutations in the AP3B1 gene, from the point of view of dysregulated RE functions.
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Affiliation(s)
- Junya Hasegawa
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
| | - Yasunori Uchida
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
| | - Kojiro Mukai
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
| | - Shoken Lee
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
| | - Tatsuyuki Matsudaira
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
| | - Tomohiko Taguchi
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
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31
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Saito-Nakano Y, Makiuchi T, Tochikura M, Gilchrist CA, Petri WA, Nozaki T. ArfX2 GTPase Regulates Trafficking From the Trans-Golgi to Lysosomes and Is Necessary for Liver Abscess Formation in the Protozoan Parasite Entamoeba histolytica. Front Cell Infect Microbiol 2022; 11:794152. [PMID: 34976870 PMCID: PMC8719317 DOI: 10.3389/fcimb.2021.794152] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 11/24/2021] [Indexed: 02/03/2023] Open
Abstract
Entamoeba histolytica is the causative agent of amoebic dysentery and liver abscess in humans. The parasitic lifestyle and the virulence of the protist require elaborate biological processes, including vesicular traffic and stress management against a variety of reactive oxygen and nitrogen species produced by the host immune response. Although the mechanisms for intracellular traffic of representative virulence factors have been investigated at molecular levels, it remains poorly understood whether and how intracellular traffic is involved in the defense against reactive oxygen and nitrogen species. Here, we demonstrate that EhArfX2, one of the Arf family of GTPases known to be involved in the regulation of vesicular traffic, was identified by comparative transcriptomic analysis of two isogenic strains: an animal-passaged highly virulent HM-1:IMSS Cl6 and in vitro maintained attenuated avirulent strain. EhArfX2 was identified as one of the most highly upregulated genes in the highly virulent strain. EhArfX2 was localized to small vesicle-like structures and largely colocalized with the marker for the trans-Golgi network SNARE, EhYkt6, but neither with the endoplasmic reticulum (ER)-resident chaperon, EhBip, nor the cis-Golgi SNARE, EhSed5, and Golgi-luminal galactosyl transferase, EhGalT. Expression of the dominant-active mutant form of EhArfX2 caused an increase in the number of lysosomes, while expression of the dominant-negative mutant led to a defect in lysosome formation and cysteine protease transport to lysosomes. Expression of the dominant-negative mutant in the virulent E. histolytica strain caused a reduction of the size of liver abscesses in a hamster model. This defect in liver abscess formation was likely at least partially attributed to reduced resistance to nitrosative, but not oxidative stress in vitro. These results showed that the EhArfX2-mediated traffic is necessary for the nitrosative stress response and virulence in the host.
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Affiliation(s)
- Yumiko Saito-Nakano
- Department of Parasitology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
| | - Takashi Makiuchi
- Department of Infectious Diseases, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | - Mami Tochikura
- Department of Parasitology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
| | - Carol A Gilchrist
- Department of Medicine, University of Virginia, Charlottesville, VA, United States
| | - William A Petri
- Department of Medicine, University of Virginia, Charlottesville, VA, United States
| | - Tomoyoshi Nozaki
- Graduate School of Medicine, The University of Tokyo, Bunkyo, Tokyo, Japan
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32
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Kanazawa T, Nishihama R, Ueda T. Normal oil body formation in Marchantia polymorpha requires functional coat protein complex I proteins. Front Plant Sci 2022; 13:979066. [PMID: 36046592 PMCID: PMC9420845 DOI: 10.3389/fpls.2022.979066] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 07/25/2022] [Indexed: 05/13/2023]
Abstract
Eukaryotic cells possess endomembrane organelles equipped with specific sets of proteins, lipids, and polysaccharides that are fundamental for realizing each organelle's specific function and shape. A tightly regulated membrane trafficking system mediates the transportation and localization of these substances. Generally, the secretory/exocytic pathway is responsible for transporting cargo to the plasma membrane and/or the extracellular space. However, in the case of oil body cells in the liverwort Marchantia polymorpha, the oil body, a liverwort-unique organelle, is thought to be formed by secretory vesicle fusion through redirection of the secretory pathway inside the cell. Although their formation mechanism remains largely unclear, oil bodies exhibit a complex and bumpy surface structure. In this study, we isolated a mutant with spherical oil bodies through visual screening of mutants with abnormally shaped oil bodies. This mutant harbored a mutation in a coat protein complex I (COPI) subunit MpSEC28, and a similar effect on oil body morphology was also detected in knockdown mutants of other COPI subunits. Fluorescently tagged MpSEC28 was localized to the periphery of the Golgi apparatus together with other subunits, suggesting that it is involved in retrograde transport from and/or in the Golgi apparatus as a component of the COPI coat. The Mpsec28 mutants also exhibited weakened stiffness of the thalli, suggesting impaired cell-cell adhesion and cell wall integrity. These findings suggest that the mechanism of cell wall biosynthesis is also involved in shaping the oil body in M. polymorpha, supporting the redirection of the secretory pathway inward the cell during oil body formation.
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Affiliation(s)
- Takehiko Kanazawa
- Division of Cellular Dynamics, National Institute for Basic Biology, Okazaki, Aichi, Japan
- The Department of Basic Biology, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi, Japan
| | - Ryuichi Nishihama
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, Noda, Japan
| | - Takashi Ueda
- Division of Cellular Dynamics, National Institute for Basic Biology, Okazaki, Aichi, Japan
- The Department of Basic Biology, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi, Japan
- *Correspondence: Takashi Ueda,
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33
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Chia J, Wang SC, Wee S, Gill DJ, Tay F, Kannan S, Verma CS, Gunaratne J, Bard FA. Src activates retrograde membrane traffic through phosphorylation of GBF1. eLife 2021; 10:68678. [PMID: 34870592 PMCID: PMC8727025 DOI: 10.7554/elife.68678] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 12/05/2021] [Indexed: 12/14/2022] Open
Abstract
The Src tyrosine kinase controls cancer-critical protein glycosylation through Golgi to ER relocation of GALNTs enzymes. How Src induces this trafficking event is unknown. Golgi to ER transport depends on the GTP exchange factor (GEF) GBF1 and small GTPase Arf1. Here, we show that Src induces the formation of tubular transport carriers containing GALNTs. The kinase phosphorylates GBF1 on 10 tyrosine residues; two of them, Y876 and Y898, are located near the C-terminus of the Sec7 GEF domain. Their phosphorylation promotes GBF1 binding to the GTPase; molecular modeling suggests partial melting of the Sec7 domain and intramolecular rearrangement. GBF1 mutants defective for these rearrangements prevent binding, carrier formation, and GALNTs relocation, while phosphomimetic GBF1 mutants induce tubules. In sum, Src promotes GALNTs relocation by promoting GBF1 binding to Arf1. Based on residue conservation, similar regulation of GEF-Arf complexes by tyrosine phosphorylation could be a conserved and widespread mechanism.
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Affiliation(s)
- Joanne Chia
- Institute of Molecular and Cell Biology, Singapore, Singapore
| | - Shyi-Chyi Wang
- Institute of Molecular and Cell Biology, Singapore, Singapore.,Institute of Bioengineering and Bioimaging, Singapore, Singapore
| | - Sheena Wee
- Institute of Molecular and Cell Biology, Singapore, Singapore
| | | | - Felicia Tay
- Institute of Molecular and Cell Biology, Singapore, Singapore
| | | | - Chandra S Verma
- Bioinformatics Institute, Singapore, Singapore.,Department of Biological Sciences, National University of Singapore, Singapore, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | | | - Frederic A Bard
- Institute of Molecular and Cell Biology, Singapore, Singapore
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34
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Wilkinson EC, Starke EL, Barbee SA. Vps54 Regulates Lifespan and Locomotor Behavior in Adult Drosophila melanogaster. Front Genet 2021; 12:762012. [PMID: 34712272 PMCID: PMC8546322 DOI: 10.3389/fgene.2021.762012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 09/28/2021] [Indexed: 11/13/2022] Open
Abstract
Vps54 is an integral subunit of the Golgi-associated retrograde protein (GARP) complex, which is involved in tethering endosome-derived vesicles to the trans-Golgi network (TGN). A destabilizing missense mutation in Vps54 causes the age-progressive motor neuron (MN) degeneration, muscle weakness, and muscle atrophy observed in the wobbler mouse, an established animal model for human MN disease. It is currently unclear how the disruption of Vps54, and thereby the GARP complex, leads to MN and muscle phenotypes. To develop a new tool to address this question, we have created an analogous model in Drosophila by generating novel loss-of-function alleles of the fly Vps54 ortholog (scattered/scat). We find that null scat mutant adults are viable but have a significantly shortened lifespan. Like phenotypes observed in the wobbler mouse, we show that scat mutant adults are male sterile and have significantly reduced body size and muscle area. Moreover, we demonstrate that scat mutant adults have significant age-progressive defects in locomotor function. Interestingly, we see sexually dimorphic effects, with scat mutant adult females exhibiting significantly stronger phenotypes. Finally, we show that scat interacts genetically with rab11 in MNs to control age-progressive muscle atrophy in adults. Together, these data suggest that scat mutant flies share mutant phenotypes with the wobbler mouse and may serve as a new genetic model system to study the cellular and molecular mechanisms underlying MN disease.
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Affiliation(s)
- Emily C Wilkinson
- Department of Biological Sciences, University of Denver, Denver, CO, United States
| | - Emily L Starke
- Department of Biological Sciences, University of Denver, Denver, CO, United States
| | - Scott A Barbee
- Department of Biological Sciences, University of Denver, Denver, CO, United States.,Molecular and Cellular Biophysics Program, University of Denver, Denver, CO, United States
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35
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Artykov AA, Yagolovich AV, Dolgikh DA, Kirpichnikov MP, Trushina DB, Gasparian ME. Death Receptors DR4 and DR5 Undergo Spontaneous and Ligand-Mediated Endocytosis and Recycling Regardless of the Sensitivity of Cancer Cells to TRAIL. Front Cell Dev Biol 2021; 9:733688. [PMID: 34660590 PMCID: PMC8514705 DOI: 10.3389/fcell.2021.733688] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 09/06/2021] [Indexed: 11/29/2022] Open
Abstract
Tumor necrosis factor-associated ligand inducing apoptosis (TRAIL) induces apoptosis through the death receptors (DRs) 4 and 5 expressed on the cell surface. Upon ligand stimulation, death receptors are rapidly internalized through clathrin-dependent and -independent mechanisms. However, there have been conflicting data on the role of death receptor endocytosis in apoptotic TRAIL signaling and possible cell type-specific differences in TRAIL signaling have been proposed. Here we have compared the kinetics of TRAIL-mediated internalization and subsequent recycling of DR4 and DR5 in resistant (HT-29 and A549) and sensitive (HCT116 and Jurkat) tumor cell lines of various origin. TRAIL stimulated the internalization of both receptors in a concentration-dependent manner with similar kinetics in sensitive and resistant cell lines without affecting the steady-state expression of DR4 and DR5 in cell lysates. Using the receptor-selective TRAIL variant DR5-B, we have shown that DR5 is internalized independently of DR4 receptor. After internalization and elimination of TRAIL from culture medium, the receptors slowly return to the plasma membrane. Within 4 h in resistant or 6 h in sensitive cells, the surface expression of receptors was completely restored. Recovery of receptors occurred both from newly synthesized molecules or from trans-Golgi network, as cycloheximide and brefeldin A inhibited this process. These agents also suppressed the expression of cell surface receptors in a time- and concentration-dependent manner, indicating that DRs undergo constitutive endocytosis. Inhibition of receptor endocytosis by sucrose led to sensitization of resistant cells to TRAIL and to an increase in its cytotoxic activity against sensitive cells. Our results confirm the universal nature of TRAIL-induced death receptor endocytosis, thus cell sensitivity to TRAIL can be associated with post-endocytic events.
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Affiliation(s)
- Artem A Artykov
- Department of Bioengineering, Institute of Bioorganic Chemistry (RAS), Moscow, Russia
| | - Anne V Yagolovich
- Department of Bioengineering, Institute of Bioorganic Chemistry (RAS), Moscow, Russia.,Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Dmitry A Dolgikh
- Department of Bioengineering, Institute of Bioorganic Chemistry (RAS), Moscow, Russia.,Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Mikhail P Kirpichnikov
- Department of Bioengineering, Institute of Bioorganic Chemistry (RAS), Moscow, Russia.,Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Daria B Trushina
- Department of X-Ray and Synchrotron Research, A.V. Shubnikov Institute of Crystallography of Federal Scientific Research Centre "Crystallography and Photonics" of Russian Academy of Sciences, Moscow, Russia
| | - Marine E Gasparian
- Department of Bioengineering, Institute of Bioorganic Chemistry (RAS), Moscow, Russia
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36
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Smith SM, Larocque G, Wood KM, Morris KL, Roseman AM, Sessions RB, Royle SJ, Smith CJ. Multi-modal adaptor-clathrin contacts drive coated vesicle assembly. EMBO J 2021; 40:e108795. [PMID: 34487371 PMCID: PMC8488560 DOI: 10.15252/embj.2021108795] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Revised: 07/30/2021] [Accepted: 08/03/2021] [Indexed: 12/17/2022] Open
Abstract
Clathrin‐coated pits are formed by the recognition of membrane and cargo by the AP2 complex and the subsequent recruitment of clathrin triskelia. A role for AP2 in coated‐pit assembly beyond initial clathrin recruitment has not been explored. Clathrin binds the β2 subunit of AP2, and several binding sites have been identified, but our structural knowledge of these interactions is incomplete and their functional importance during endocytosis is unclear. Here, we analysed the cryo‐EM structure of clathrin cages assembled in the presence of β2 hinge‐appendage (β2HA). We find that the β2‐appendage binds in at least two positions in the cage, demonstrating that multi‐modal binding is a fundamental property of clathrin‐AP2 interactions. In one position, β2‐appendage cross‐links two adjacent terminal domains from different triskelia. Functional analysis of β2HA‐clathrin interactions reveals that endocytosis requires two clathrin interaction sites: a clathrin‐box motif on the hinge and the “sandwich site” on the appendage. We propose that β2‐appendage binding to more than one triskelion is a key feature of the system and likely explains why assembly is driven by AP2.
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Affiliation(s)
- Sarah M Smith
- School of Life Sciences, University of Warwick, Coventry, UK
| | - Gabrielle Larocque
- Centre for Mechanochemical Cell Biology, Warwick Medical School, University of Warwick, Coventry, UK
| | | | - Kyle L Morris
- School of Life Sciences, University of Warwick, Coventry, UK
| | - Alan M Roseman
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
| | | | - Stephen J Royle
- Centre for Mechanochemical Cell Biology, Warwick Medical School, University of Warwick, Coventry, UK
| | - Corinne J Smith
- School of Life Sciences, University of Warwick, Coventry, UK
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37
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Higuchi Y. Membrane Traffic in Aspergillus oryzae and Related Filamentous Fungi. J Fungi (Basel) 2021; 7:jof7070534. [PMID: 34356913 PMCID: PMC8303533 DOI: 10.3390/jof7070534] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 06/29/2021] [Accepted: 06/29/2021] [Indexed: 11/16/2022] Open
Abstract
The industrially important filamentous fungus Aspergillus oryzae, known as the yellow Koji mold and also designated the Japanese National fungus, has been investigated for understanding the intracellular membrane trafficking machinery due to the great ability of valuable enzyme production. The underlying molecular mechanisms of the secretory pathway delineate the main secretion route from the hyphal tip via the vesicle cluster Spitzenkörper, but also there is a growing body of evidence that septum-directed and unconventional secretion occurs in A. oryzae hyphal cells. Moreover, not only the secretory pathway but also the endocytic pathway is crucial for protein secretion, especially having a role in apical endocytic recycling. As a hallmark of multicellular filamentous fungal cells, endocytic organelles early endosome and vacuole are quite dynamic: the former exhibits constant long-range motility through the hyphal cells and the latter displays pleiomorphic structures in each hyphal region. These characteristics are thought to have physiological roles, such as supporting protein secretion and transporting nutrients. This review summarizes molecular and physiological mechanisms of membrane traffic, i.e., secretory and endocytic pathways, in A. oryzae and related filamentous fungi and describes the further potential for industrial applications.
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Affiliation(s)
- Yujiro Higuchi
- Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, 744 Motooka, Fukuoka 819-0395, Japan
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38
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Willy NM, Colombo F, Huber S, Smith AC, Norton EG, Kural C, Cocucci E. CALM supports clathrin-coated vesicle completion upon membrane tension increase. Proc Natl Acad Sci U S A 2021; 118:e2010438118. [PMID: 34155137 DOI: 10.1073/pnas.2010438118] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The most represented components of clathrin-coated vesicles (CCVs) are clathrin triskelia and the adaptors clathrin assembly lymphoid myeloid leukemia protein (CALM) and the heterotetrameric complex AP2. Investigation of the dynamics of AP180-amino-terminal-homology (ANTH) recruitment during CCV formation has been hampered by CALM toxicity upon overexpression. We used knock-in gene editing to express a C-terminal-attached fluorescent version of CALM, while preserving its endogenous expression levels, and cutting-edge live-cell microscopy approaches to study CALM recruitment at forming CCVs. Our results demonstrate that CALM promotes vesicle completion upon membrane tension increase as a function of the amount of this adaptor present. Since the expression of adaptors, including CALM, differs among cells, our data support a model in which the efficiency of clathrin-mediated endocytosis is tissue specific and explain why CALM is essential during embryogenesis and red blood cell development.
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39
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Castaings L, Alcon C, Kosuth T, Correia D, Curie C. Manganese triggers phosphorylation-mediated endocytosis of the Arabidopsis metal transporter NRAMP1. Plant J 2021; 106:1328-1337. [PMID: 33735495 DOI: 10.1111/tpj.15239] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 03/12/2021] [Accepted: 03/15/2021] [Indexed: 06/12/2023]
Abstract
The NATURAL RESISTANCE-ASSOCIATED MACROPHAGE PROTEIN 1 (NRAMP1) transporter guarantees plant survival of manganese (Mn) deficiency by mediating Mn entry into root cells. Unlike other high-affinity metal transporters, NRAMP1 is only slightly regulated at the transcriptional level. We show here that adequate Mn content in tissues is safeguarded through a tight control of the quantity of NRAMP1 present at the surface of root cells. Depending on Mn availability, an NRAMP1-GFP fusion protein cycles dynamically between the plasma membrane (PM) and endosomal compartments. This involves a clathrin-mediated endocytosis pathway, as disrupting this pathway in auxilin-overexpressor lines prevents NRAMP1 internalization. Mutation of the phosphorylated serine residues 20, 22 and 24 in the cytosol-exposed N terminus of NRAMP1 alters its membrane distribution. Indeed, a phospho-dead mutation stabilizes NRAMP1 at the PM, regardless of the Mn regime, and dramatically reduces plant tolerance to Mn toxicity. Conversely a phosphomimetic mutant is constitutively internalized into endosomes. Together, these data establish that phosphorylation of NRAMP1 is the trigger for its Mn-induced endocytosis and represents the main level of regulation of this transporter. Furthermore, the extent of Mn toxicity observed when interrupting NRAMP1 membrane cycling undermines the dogma that Mn is only marginally toxic to plants.
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Affiliation(s)
- Loren Castaings
- BPMP, Univ Montpellier, CNRS, INRAE, Institut Agro, Montpellier, France
| | - Carine Alcon
- BPMP, Univ Montpellier, CNRS, INRAE, Institut Agro, Montpellier, France
| | - Thibault Kosuth
- BPMP, Univ Montpellier, CNRS, INRAE, Institut Agro, Montpellier, France
| | - David Correia
- BPMP, Univ Montpellier, CNRS, INRAE, Institut Agro, Montpellier, France
| | - Catherine Curie
- BPMP, Univ Montpellier, CNRS, INRAE, Institut Agro, Montpellier, France
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40
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Galindo A, Planelles-Herrero VJ, Degliesposti G, Munro S. Cryo-EM structure of metazoan TRAPPIII, the multi-subunit complex that activates the GTPase Rab1. EMBO J 2021; 40:e107608. [PMID: 34018214 PMCID: PMC8204870 DOI: 10.15252/embj.2020107608] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 03/30/2021] [Accepted: 04/11/2021] [Indexed: 12/19/2022] Open
Abstract
The TRAPP complexes are nucleotide exchange factors that play essential roles in membrane traffic and autophagy. TRAPPII activates Rab11, and TRAPPIII activates Rab1, with the two complexes sharing a core of small subunits that affect nucleotide exchange but being distinguished by specific large subunits that are essential for activity in vivo. Crystal structures of core subunits have revealed the mechanism of Rab activation, but how the core and the large subunits assemble to form the complexes is unknown. We report a cryo‐EM structure of the entire Drosophila TRAPPIII complex. The TRAPPIII‐specific subunits TRAPPC8 and TRAPPC11 hold the catalytic core like a pair of tongs, with TRAPPC12 and TRAPPC13 positioned at the joint between them. TRAPPC2 and TRAPPC2L link the core to the two large arms, with the interfaces containing residues affected by disease‐causing mutations. The TRAPPC8 arm is positioned such that it would contact Rab1 that is bound to the core, indicating how the arm could determine the specificity of the complex. A lower resolution structure of TRAPPII shows a similar architecture and suggests that the TRAPP complexes evolved from a single ur‐TRAPP.
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Affiliation(s)
| | | | | | - Sean Munro
- MRC Laboratory of Molecular Biology, Cambridge, UK
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41
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Borges JP, Mekhail K, Fairn GD, Antonescu CN, Steinberg BE. Modulation of Pathological Pain by Epidermal Growth Factor Receptor. Front Pharmacol 2021; 12:642820. [PMID: 34054523 PMCID: PMC8149758 DOI: 10.3389/fphar.2021.642820] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 04/26/2021] [Indexed: 12/18/2022] Open
Abstract
Chronic pain has been widely recognized as a major public health problem that impacts multiple aspects of patient quality of life. Unfortunately, chronic pain is often resistant to conventional analgesics, which are further limited by their various side effects. New therapeutic strategies and targets are needed to better serve the millions of people suffering from this devastating disease. To this end, recent clinical and preclinical studies have implicated the epidermal growth factor receptor signaling pathway in chronic pain states. EGFR is one of four members of the ErbB family of receptor tyrosine kinases that have key roles in development and the progression of many cancers. EGFR functions by activating many intracellular signaling pathways following binding of various ligands to the receptor. Several of these signaling pathways, such as phosphatidylinositol 3-kinase, are known mediators of pain. EGFR inhibitors are known for their use as cancer therapeutics but given recent evidence in pilot clinical and preclinical investigations, may have clinical use for treating chronic pain. Here, we review the clinical and preclinical evidence implicating EGFR in pathological pain states and provide an overview of EGFR signaling highlighting how EGFR and its ligands drive pain hypersensitivity and interact with important pain pathways such as the opioid system.
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Affiliation(s)
- Jazlyn P Borges
- Neurosciences and Mental Health Program, The Hospital for Sick Children, Toronto, ON, Canada.,Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Katrina Mekhail
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada.,Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Gregory D Fairn
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada.,Department of Biochemistry, University of Toronto, Toronto, ON, Canada.,Department of Surgery, University of Toronto, Toronto, ON, Canada.,Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada.,Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada
| | - Costin N Antonescu
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada.,Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada
| | - Benjamin E Steinberg
- Neurosciences and Mental Health Program, The Hospital for Sick Children, Toronto, ON, Canada.,Department of Physiology, University of Toronto, Toronto, ON, Canada.,Department of Anesthesia and Pain Medicine, The Hospital for Sick Children, Toronto, ON, Canada
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42
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Abstract
We have previously shown that Rab34 is an important regulator of ciliogenesis and that its unique long N-terminal region (amino acids 1-49) is essential for ciliogenesis in certain cultured mammalian cells. In the present study, we performed an in-depth deletion analysis of the N-terminal region of Rab34 together with Ala-based site-directed mutagenesis to identify the essential amino acids that are required for serum-starvation-induced ciliogenesis in hTERT-RPE1 cells. The results showed that a Rab34 mutant lacking an N-terminal 18 amino acids and a Rab34 mutant carrying an LPQ-to-AAA mutation (amino acids 16-18) failed to rescue a Rab34-KO phenotype (i.e., defect in ciliogenesis). Our findings suggest that the LPQ sequence of Rab34 is crucial for ciliogenesis in hTERT-RPE1 cells.Abbreviations: AA, amino acid(s); ac-Tub, acetylated tubulin; bsr, blasticidin S-resistant gene; HRP, horseradish peroxidase; hTERT-RPE1, human telomerase reverse transcriptase retinal pigment epithelium 1; KO, knockout; NS, not significant; PBS, phosphate-buffered saline; puro, puromycin-resistant gene.
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Affiliation(s)
- Mai E Oguchi
- Laboratory of Membrane Trafficking Mechanisms, Department of Integrative Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Yuta Homma
- Laboratory of Membrane Trafficking Mechanisms, Department of Integrative Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Mitsunori Fukuda
- Laboratory of Membrane Trafficking Mechanisms, Department of Integrative Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Japan
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43
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Chandra M, Kendall AK, Jackson LP. Toward Understanding the Molecular Role of SNX27/Retromer in Human Health and Disease. Front Cell Dev Biol 2021; 9:642378. [PMID: 33937239 PMCID: PMC8083963 DOI: 10.3389/fcell.2021.642378] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 03/22/2021] [Indexed: 11/30/2022] Open
Abstract
Aberrations in membrane trafficking pathways have profound effects in cellular dynamics of cellular sorting processes and can drive severe physiological outcomes. Sorting nexin 27 (SNX27) is a metazoan-specific sorting nexin protein from the PX-FERM domain family and is required for endosomal recycling of many important transmembrane receptors. Multiple studies have shown SNX27-mediated recycling requires association with retromer, one of the best-known regulators of endosomal trafficking. SNX27/retromer downregulation is strongly linked to Down's Syndrome (DS) via glutamate receptor dysfunction and to Alzheimer's Disease (AD) through increased intracellular production of amyloid peptides from amyloid precursor protein (APP) breakdown. SNX27 is further linked to addiction via its role in potassium channel trafficking, and its over-expression is linked to tumorigenesis, cancer progression, and metastasis. Thus, the correct sorting of multiple receptors by SNX27/retromer is vital for normal cellular function to prevent human diseases. The role of SNX27 in regulating cargo recycling from endosomes to the cell surface is firmly established, but how SNX27 assembles with retromer to generate tubulovesicular carriers remains elusive. Whether SNX27/retromer may be a putative therapeutic target to prevent neurodegenerative disease is now an emerging area of study. This review will provide an update on our molecular understanding of endosomal trafficking events mediated by the SNX27/retromer complex on endosomes.
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Affiliation(s)
- Mintu Chandra
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, United States
- Center for Structural Biology, Vanderbilt University, Nashville, TN, United States
| | - Amy K. Kendall
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, United States
- Center for Structural Biology, Vanderbilt University, Nashville, TN, United States
| | - Lauren P. Jackson
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, United States
- Center for Structural Biology, Vanderbilt University, Nashville, TN, United States
- Department of Biochemistry, Vanderbilt University, Nashville, TN, United States
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44
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Milev MP, Saint-Dic D, Zardoui K, Klopstock T, Law C, Distelmaier F, Sacher M. The phenotype associated with variants in TANGO2 may be explained by a dual role of the protein in ER-to-Golgi transport and at the mitochondria. J Inherit Metab Dis 2021; 44:426-437. [PMID: 32909282 DOI: 10.1002/jimd.12312] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 08/13/2020] [Accepted: 08/31/2020] [Indexed: 12/17/2022]
Abstract
TANGO2 variants result in a complex disease phenotype consisting of recurrent crisis-induced rhabdomyolysis, encephalopathy, seizures, lactic acidosis, hypoglycemia, and cardiac arrhythmias. Although first described in a fruit fly model as a protein necessary for some aspect of Golgi function and organization, its role in the cell at a fundamental level has not been addressed. Such studies are necessary to better counsel families regarding treatment options and nutrition management to mitigate the metabolic aspects of the disease. The few studies performed to address the pathway(s) in which TANGO2 functions have led to enigmatic results, with some suggesting defects in membrane traffic while others suggest unknown mitochondrial defects. Here, we have performed a robust membrane trafficking assay on fibroblasts derived from three different individuals harboring TANGO2 variants and show that there is a significant delay in the movement of cargo between the endoplasmic reticulum and the Golgi. Importantly, this delay was attributed to a defect in TANGO2 function. We further show that a portion of TANGO2 protein localizes to the mitochondria through a necessary but not sufficient stretch of amino acids at the amino terminus of the protein. Fibroblasts from affected individuals also displayed changes in mitochondrial morphology. We conclude that TANGO2 functions in both membrane trafficking and in some as yet undetermined role in mitochondria physiology. The phenotype of affected individuals can be partially explained by this dual involvement of the protein.
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Affiliation(s)
- Miroslav P Milev
- Department of Biology, Concordia University, Montreal Quebec, Canada
| | - Djenann Saint-Dic
- Department of Biology, Concordia University, Montreal Quebec, Canada
| | - Khashayar Zardoui
- Department of Biology, Concordia University, Montreal Quebec, Canada
| | - Thomas Klopstock
- Department of Neurology, Friedrich-Baur-Institute, Ludwig-Maximilians-University, Munich, Germany
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Christopher Law
- Centre for Microscopy and Cellular Imaging, Concordia University, Quebec, Canada
| | - Felix Distelmaier
- Department of General Pediatrics, Neonatology and Pediatric Cardiology, University Children's Hospital Düsseldorf, Medical faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Michael Sacher
- Department of Biology, Concordia University, Montreal Quebec, Canada
- Department of Anatomy and Cell Biology, McGill University, Quebec, Canada
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45
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Kitano M, Kizuka Y, Sobajima T, Nakano M, Nakajima K, Misaki R, Itoyama S, Harada Y, Harada A, Miyoshi E, Taniguchi N. Rab11-mediated post-Golgi transport of the sialyltransferase ST3GAL4 suggests a new mechanism for regulating glycosylation. J Biol Chem 2021; 296:100354. [PMID: 33524390 DOI: 10.1016/j.jbc.2021.100354] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 01/20/2021] [Accepted: 01/27/2021] [Indexed: 02/06/2023] Open
Abstract
Glycosylation, the most common posttranslational modification of proteins, is a stepwise process that relies on tight regulation of subcellular glycosyltransferase location to control the addition of each monosaccharide. Glycosyltransferases primarily reside and function in the endoplasmic reticulum (ER) and the Golgi apparatus; whether and how they traffic beyond the Golgi, how this trafficking is controlled, and how it impacts glycosylation remain unclear. Our previous work identified a connection between N-glycosylation and Rab11, a key player in the post-Golgi transport that connects recycling endosomes and other compartments. To learn more about the specific role of Rab11, we knocked down Rab11 in HeLa cells. Our findings indicate that Rab11 knockdown results in a dramatic enhancement in the sialylation of N-glycans. Structural analyses of glycans using lectins and LC-MS revealed that α2,3-sialylation is selectively enhanced, suggesting that an α2,3-sialyltransferase that catalyzes the sialyation of glycoproteins is activated or upregulated as the result of Rab11 knockdown. ST3GAL4 is the major α2,3-sialyltransferase that acts on N-glycans; we demonstrated that the localization of ST3GAL4, but not the levels of its mRNA, protein, or donor substrate, was altered by Rab11 depletion. In knockdown cells, ST3GAL4 is densely distributed in the trans-Golgi network, compared with the wider distribution in the Golgi and in other peripheral puncta in control cells, whereas the α2,6-sialyltransferase ST6GAL1 is predominantly localized to the Golgi regardless of Rab11 knockdown. This indicates that Rab11 may negatively regulate α2,3-sialylation by transporting ST3GAL4 to post-Golgi compartments (PGCs), which is a novel mechanism of glycosyltransferase regulation.
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46
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Koinuma S, Negishi R, Nomura R, Sato K, Kojima T, Segi-Nishida E, Goitsuka R, Iwakura Y, Wada N, Koriyama Y, Kiryu-Seo S, Kiyama H, Nakamura T. TC10, a Rho family GTPase, is required for efficient axon regeneration in a neuron-autonomous manner. J Neurochem 2020; 157:1196-1206. [PMID: 33156548 DOI: 10.1111/jnc.15235] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 10/28/2020] [Accepted: 11/01/2020] [Indexed: 12/12/2022]
Abstract
Intracellular signaling pathways that promote axon regeneration are closely linked to the mechanism of neurite outgrowth. TC10, a signaling molecule that acts on neurite outgrowth through membrane transport, is a member of the Rho family G proteins. Axon injury increases the TC10 levels in motor neurons, suggesting that TC10 may be involved in axon regeneration. In this study, we tried to understand the roles of TC10 in the nervous system using TC10 knock-out mice. In cultured hippocampal neurons, TC10 ablation significantly reduced axon elongation without affecting ordinary polarization. We determined a role of TC10 in microtubule stabilization at the growth cone neck; therefore, we assume that TC10 limits axon retraction and promotes in vitro axon outgrowth. In addition, there were no notable differences in the size and structure of brains during prenatal and postnatal development between wild-type and TC10 knock-out mice. In motor neurons, axon regeneration after injury was strongly suppressed in mice lacking TC10 (both in conventional and injured nerve specific deletion). In retinal ganglion cells, TC10 ablation suppressed the axon regeneration stimulated by intraocular inflammation and cAMP after optic nerve crush. These results show that TC10 plays an important role in axon regeneration in both the peripheral and central nervous systems, and the role of TC10 in peripheral axon regeneration is neuron-intrinsic.
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Affiliation(s)
- Shingo Koinuma
- Research Institute for Biomedical Sciences, Tokyo University of Science, Noda, Japan
| | - Ryota Negishi
- Research Institute for Biomedical Sciences, Tokyo University of Science, Noda, Japan.,Department of Applied Biological Science, Tokyo University of Science, Noda, Japan
| | - Riko Nomura
- Research Institute for Biomedical Sciences, Tokyo University of Science, Noda, Japan.,Department of Biological Science and Technology, Tokyo University of Science, Tokyo, Japan
| | - Kazuki Sato
- Research Institute for Biomedical Sciences, Tokyo University of Science, Noda, Japan
| | - Takuya Kojima
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Eri Segi-Nishida
- Department of Biological Science and Technology, Tokyo University of Science, Tokyo, Japan
| | - Ryo Goitsuka
- Research Institute for Biomedical Sciences, Tokyo University of Science, Noda, Japan
| | - Yoichiro Iwakura
- Research Institute for Biomedical Sciences, Tokyo University of Science, Noda, Japan
| | - Naoyuki Wada
- Department of Applied Biological Science, Tokyo University of Science, Noda, Japan
| | - Yoshiki Koriyama
- Faculty of Pharmaceutical Sciences, Suzuka University of Medical Science, Suzuka, Japan
| | - Sumiko Kiryu-Seo
- Department of Functional Anatomy and Neuroscience, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Hiroshi Kiyama
- Department of Functional Anatomy and Neuroscience, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Takeshi Nakamura
- Research Institute for Biomedical Sciences, Tokyo University of Science, Noda, Japan
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47
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Fukuda M. Rab GTPases: Key players in melanosome biogenesis, transport, and transfer. Pigment Cell Melanoma Res 2020; 34:222-235. [PMID: 32997883 DOI: 10.1111/pcmr.12931] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 09/23/2020] [Indexed: 12/12/2022]
Abstract
Melanosomes are specialized intracellular organelles that produce and store melanin pigments in melanocytes, which are present in several mammalian tissues and organs, including the skin, hair, and eyes. Melanosomes form and mature stepwise (stages I-IV) in melanocytes and then are transported toward the plasma membrane along the cytoskeleton. They are subsequently transferred to neighboring keratinocytes by a largely unknown mechanism, and incorporated melanosomes are transported to the perinuclear region of the keratinocytes where they form melanin caps. Melanocytes also extend several dendrites that facilitate the efficient transfer of the melanosomes to the keratinocytes. Since the melanosome biogenesis, transport, and transfer steps require multiple membrane trafficking processes, Rab GTPases that are conserved key regulators of membrane traffic in all eukaryotes are crucial for skin and hair pigmentation. Dysfunctions of two Rab isoforms, Rab27A and Rab38, are known to cause a hypopigmentation phenotype in human type 2 Griscelli syndrome patients and in chocolate mice (related to Hermansky-Pudlak syndrome), respectively. In this review article, I review the literature on the functions of each Rab isoform and its upstream and downstream regulators in mammalian melanocytes and keratinocytes.
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Affiliation(s)
- Mitsunori Fukuda
- Laboratory of Membrane Trafficking Mechanisms, Department of Integrative Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan
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48
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Redlingshöfer L, McLeod F, Chen Y, Camus MD, Burden JJ, Palomer E, Briant K, Dannhauser PN, Salinas PC, Brodsky FM. Clathrin light chain diversity regulates membrane deformation in vitro and synaptic vesicle formation in vivo. Proc Natl Acad Sci U S A 2020; 117:23527-38. [PMID: 32907943 DOI: 10.1073/pnas.2003662117] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
This study reveals that diversity of clathrin light chain (CLC) subunits alters clathrin properties and demonstrates that the two neuronal CLC subunits work together for optimal clathrin function in synaptic vesicle formation. Our findings establish a role for CLC diversity in synaptic transmission and illustrate how CLC variability expands the complexity of clathrin to serve tissue-specific functions. Clathrin light chain (CLC) subunits in vertebrates are encoded by paralogous genes CLTA and CLTB, and both gene products are alternatively spliced in neurons. To understand how this CLC diversity influences neuronal clathrin function, we characterized the biophysical properties of clathrin comprising individual CLC variants for correlation with neuronal phenotypes of mice lacking either CLC-encoding gene. CLC splice variants differentially influenced clathrin knee conformation within assemblies, and clathrin with neuronal CLC mixtures was more effective in membrane deformation than clathrin with single neuronal isoforms nCLCa or nCLCb. Correspondingly, electrophysiological recordings revealed that neurons from mice lacking nCLCa or nCLCb were both defective in synaptic vesicle replenishment. Mice with only nCLCb had a reduced synaptic vesicle pool and impaired neurotransmission compared to WT mice, while nCLCa-only mice had increased synaptic vesicle numbers, restoring normal neurotransmission. These findings highlight differences between the CLC isoforms and show that isoform mixing influences tissue-specific clathrin activity in neurons, which requires their functional balance.
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49
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Silva PM, Puerner C, Seminara A, Bassilana M, Arkowitz RA. Secretory Vesicle Clustering in Fungal Filamentous Cells Does Not Require Directional Growth. Cell Rep 2020; 28:2231-2245.e5. [PMID: 31433995 DOI: 10.1016/j.celrep.2019.07.062] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Revised: 04/22/2019] [Accepted: 07/18/2019] [Indexed: 11/27/2022] Open
Abstract
During symmetry breaking, the highly conserved Rho GTPase Cdc42 becomes stabilized at a defined site via an amplification process. However, little is known about how a new polarity site is established in an already asymmetric cell-a critical process in a changing environment. The human fungal pathogen Candida albicans switches from budding to filamentous growth in response to external cues, a transition controlled by Cdc42. Here, we have used optogenetic manipulation of cell polarity to reset growth in asymmetric filamentous C. albicans cells. We show that increasing the level of active Cdc42 on the plasma membrane results in disruption of the exocyst subunit Sec3 localization and a striking de novo clustering of secretory vesicles. This new cluster of secretory vesicles is highly dynamic, moving by hops and jumps, until a new growth site is established. Our results reveal that secretory vesicle clustering can occur in the absence of directional growth.
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Affiliation(s)
- Patrícia M Silva
- Université Côte d'Azur, CNRS, INSERM, Institute of Biology Valrose (iBV), Parc Valrose, Nice, France
| | - Charles Puerner
- Université Côte d'Azur, CNRS, INSERM, Institute of Biology Valrose (iBV), Parc Valrose, Nice, France
| | - Agnese Seminara
- Université Côte d'Azur, CNRS, Institute Physics of Nice (INPHYNI), Ave. J. Vallot, Nice, France
| | - Martine Bassilana
- Université Côte d'Azur, CNRS, INSERM, Institute of Biology Valrose (iBV), Parc Valrose, Nice, France
| | - Robert A Arkowitz
- Université Côte d'Azur, CNRS, INSERM, Institute of Biology Valrose (iBV), Parc Valrose, Nice, France.
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50
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Kitao T, Nagai H, Kubori T. Divergence of Legionella Effectors Reversing Conventional and Unconventional Ubiquitination. Front Cell Infect Microbiol 2020; 10:448. [PMID: 32974222 PMCID: PMC7472693 DOI: 10.3389/fcimb.2020.00448] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 07/21/2020] [Indexed: 02/05/2023] Open
Abstract
The intracellular bacterial pathogen Legionella pneumophila employs bacteria-derived effector proteins in a variety of functions to exploit host cellular systems. The ubiquitination machinery constitutes a crucial eukaryotic system for the regulation of numerous cellular processes, and is a representative target for effector-mediated bacterial manipulation. L. pneumophila transports over 300 effector proteins into host cells through its Dot/Icm type IV secretion system. Among these, several effector proteins have been found to function as ubiquitin ligases, including unprecedented enzymes that catalyze ubiquitination through unconventional mechanisms. Recent studies have identified many L. pneumophila effector proteins that can interfere with ubiquitination. These effectors include proteins that are distantly related to the ovarian tumor protein superfamily described as deubiquitinases (DUBs), which regulate important signaling cascades in human cells. Intriguingly, L. pneumophila DUBs are not limited to enzymes that exhibit canonical DUB activity. Some L. pneumophila DUBs can catalyze the cleavage of the unconventional linkage between ubiquitin and substrates. Furthermore, novel mechanisms have been found that adversely affect the function of specific ubiquitin ligases; for instance, effector-mediated posttranslational modifications of ubiquitin ligases result in the inhibition of their activity. In the context of L. pneumophila infection, the existence of enzymes that reverse ubiquitination primarily relates to a fine tuning of biogenesis and remodeling of the Legionella-containing vacuole as a replicative niche. The complexity of the effector arrays reflects sophisticated strategies that bacteria have adopted to adapt their host environment and enable their survival in host cells. This review summarizes the current state of knowledge on the divergent mechanisms of the L. pneumophila effectors that can reverse ubiquitination, which is mediated by other effectors as well as the host ubiquitin machinery.
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Affiliation(s)
- Tomoe Kitao
- Department of Microbiology, Graduate School of Medicine, Gifu University, Gifu, Japan
| | - Hiroki Nagai
- Department of Microbiology, Graduate School of Medicine, Gifu University, Gifu, Japan
- G-CHAIN, Gifu University, Gifu, Japan
| | - Tomoko Kubori
- Department of Microbiology, Graduate School of Medicine, Gifu University, Gifu, Japan
- G-CHAIN, Gifu University, Gifu, Japan
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