1
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Vassilopoulos S, Montagnac G. Clathrin assemblies at a glance. J Cell Sci 2024; 137:jcs261674. [PMID: 38668719 DOI: 10.1242/jcs.261674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2024] Open
Abstract
Clathrin assembles into honeycomb-like lattices at the plasma membrane but also on internal membranes, such as at the Golgi and tubular endosomes. Clathrin assemblies primarily regulate the intracellular trafficking of different cargoes, but clathrin also has non-endocytic functions in cell adhesion through interactions with specific integrins, contributes to intraluminal vesicle formation by forming flat bilayered coats on endosomes and even assembles on kinetochore k-fibers during mitosis. In this Cell Science at a Glance article and the accompanying poster, we review our current knowledge on the different types of canonical and non-canonical membrane-associated clathrin assemblies in mammalian cells, as observed by thin-section or platinum replica electron microscopy in various cell types, and discuss how the structural plasticity of clathrin contributes to its functional diversity.
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Affiliation(s)
- Stéphane Vassilopoulos
- Sorbonne Université, Inserm U974, Institut de Myologie, Centre de Recherche en Myologie, 75013 Paris, France
| | - Guillaume Montagnac
- Inserm U1279, Gustave Roussy Institute, Université Paris-Saclay, 94800 Villejuif, France
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2
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Sittewelle M, Royle SJ. Passive diffusion accounts for the majority of intracellular nanovesicle transport. Life Sci Alliance 2024; 7:e202302406. [PMID: 37857498 PMCID: PMC10587482 DOI: 10.26508/lsa.202302406] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 10/12/2023] [Accepted: 10/12/2023] [Indexed: 10/21/2023] Open
Abstract
During membrane trafficking, a vesicle formed at the donor compartment must travel to the acceptor membrane before fusing. For large carriers, it is established that this transport is motor-driven; however, the mode by which small vesicles, which outnumber larger carriers, are transported is poorly characterized. Here, we show that intracellular nanovesicles (INVs), a substantial class of small vesicles, are highly mobile within cells and that this mobility depends almost entirely on passive diffusion (0.1-0.3 μm2 s-1). Using single particle tracking, we describe how other small trafficking vesicles have a similar diffusive mode of transport that contrasts with the motor-dependent movement of larger endolysosomal carriers. We also demonstrate that a subset of INVs is involved in exocytosis and that delivery of cargo to the plasma membrane during exocytosis is decreased when diffusion of INVs is specifically restricted. Our results suggest that passive diffusion is sufficient to explain the majority of small vesicle transport.
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Affiliation(s)
- Méghane Sittewelle
- https://ror.org/01a77tt86 Centre for Mechanochemical Cell Biology and Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, UK
| | - Stephen J Royle
- https://ror.org/01a77tt86 Centre for Mechanochemical Cell Biology and Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, UK
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3
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Clippinger AK, Naismith TV, Yoo W, Jansen S, Kast DJ, Hanson PI. IST1 regulates select recycling pathways. Traffic 2024; 25:e12921. [PMID: 37926552 PMCID: PMC11027954 DOI: 10.1111/tra.12921] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 08/21/2023] [Accepted: 09/23/2023] [Indexed: 11/07/2023]
Abstract
ESCRTs (Endosomal Sorting Complex Required for Transports) are a modular set of protein complexes with membrane remodeling activities that include the formation and release of intraluminal vesicles (ILVs) to generate multivesicular endosomes. While most of the 12 ESCRT-III proteins are known to play roles in ILV formation, IST1 has been associated with a wider range of endosomal remodeling events. Here, we extend previous studies of IST1 function in endosomal trafficking and confirm that IST1, along with its binding partner CHMP1B, contributes to scission of early endosomal carriers. Functionally, depleting IST1 impaired delivery of transferrin receptor from early/sorting endosomes to the endocytic recycling compartment and instead increased its rapid recycling to the plasma membrane via peripheral endosomes enriched in the clathrin adaptor AP-1. IST1 is also important for export of mannose 6-phosphate receptor from early/sorting endosomes. Examination of IST1 binding partners on endosomes revealed that IST1 interacts with the MIT domain-containing sorting nexin SNX15, a protein previously reported to regulate endosomal recycling. Our kinetic and spatial analyses establish that SNX15 and IST1 occupy a clathrin-containing subdomain on the endosomal perimeter distinct from those previously implicated in cargo retrieval or degradation. Using live-cell microscopy, we see that SNX15 and CHMP1B alternately recruit IST1 to this subdomain or the base of endosomal tubules. These findings indicate that IST1 contributes to a subset of recycling pathways from the early/sorting endosome.
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Affiliation(s)
- Amy K Clippinger
- Department of Cell Biology and Physiology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Teresa V Naismith
- Department of Cell Biology and Physiology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Wonjin Yoo
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Silvia Jansen
- Department of Cell Biology and Physiology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - David J Kast
- Department of Cell Biology and Physiology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Phyllis I Hanson
- Department of Cell Biology and Physiology, Washington University in St. Louis, St. Louis, Missouri, USA
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, USA
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4
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Kaur I, Behl T, Sundararajan G, Panneerselvam P, Vijayakumar AR, Senthilkumar GP, Venkatachalam T, Jaglan D, Yadav S, Anwer K, Fuloria NK, Sehgal A, Gulati M, Chigurupati S. BIN1 in the Pursuit of Ousting the Alzheimer's Reign: Impact on Amyloid and Tau Neuropathology. Neurotox Res 2023; 41:698-707. [PMID: 37847429 DOI: 10.1007/s12640-023-00670-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 09/12/2023] [Accepted: 09/19/2023] [Indexed: 10/18/2023]
Abstract
Alzheimer's disease contributes to 60-70% of all dementia cases in the general population. Belonging to the BIN1/amphiphysin/RVS167 (BAR) superfamily, the bridging integrator (BIN1) has been identified to impact two major pathological hallmarks in Alzheimer's disease (AD), i.e., amyloid beta (Aβ) and tau accumulation. Aβ accumulation is found to increase by BIN1 knockdown in cortical neurons in late-onset AD, due to BACE1 accumulation at enlarged early endosomes. Two BIN1 mutants, KR and PL, were identified to exhibit Aβ accumulation. Furthermore, BIN1 deficiency by BIN1-related polymorphisms impairs the interaction with tau, thus elevating tau phosphorylation, altering synapse structure and tau function. Even though the precise role of BIN1 in the neuronal tissue needs further investigation, the authors aim to throw light on the potential of BIN1 and unfold its implications on tau and Aβ pathology, to aid AD researchers across the globe to examine BIN1, as an appropriate target gene for disease management.
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Affiliation(s)
- Ishnoor Kaur
- College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Tapan Behl
- School of Health Sciences and Technology, University of Petroleum and Energy Studies, Bidholi, Dehradun, India.
| | - G Sundararajan
- Department of Pharmaceutics, Faculty of Pharmacy, Sree Balaji Medical College and Hospital, Chromepet, Chennai, Tamil Nadu, India
| | - P Panneerselvam
- Faculty of Pharmacy, Sree Balaji Medical College and Hospital Campus, Bharath Institute of Higher Education and Research, Chennai, Tamil Nadu, India
| | - A R Vijayakumar
- Faculty of Pharmacy, Sree Balaji Medical College and Hospital Campus, Bharath Institute of Higher Education and Research, Chennai, Tamil Nadu, India
| | - G P Senthilkumar
- Faculty of Pharmacy, Sree Balaji Medical College and Hospital Campus, Bharath Institute of Higher Education and Research, Chennai, Tamil Nadu, India
| | - T Venkatachalam
- Department of Pharmaceutical Chemistry, JKKMMRFs-Amnai JKK Sampoorani Ammal College of Pharmacy, Komarapalayam, Tamil Nadu, India
| | - Dharmender Jaglan
- Faculty of Pharmaceutical Sciences, DAV University, Jalandhar, Punjab, India
| | - Shivam Yadav
- School of Pharmaceutical Sciences, Department of Pharmaceutical Sciences, Chhatrapti Shahu Ji Maharaj University, Uttar Pradesh, Kanpur, India
| | - Khalid Anwer
- Department of Pharmaceutics, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Alkharj, Saudi Arabia
| | - Neeraj Kumar Fuloria
- Faculty of Pharmacy, AIMST University, Bedong, Kedah, Malaysia
- Center for Transdisciplinary Research, Department of Pharmacology, Saveetha Institute of Medical and Technical Sciences, Saveetha Dental College and Hospital, Saveetha University, Chennai, Tamil Nadu, India
| | - Aayush Sehgal
- GHG Khalsa College of Pharmacy, Gurusar Sadhar, Punjab, India
| | - Monica Gulati
- School of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab, 1444411, India
- Faculty of Health, ARCCIM, University of Technology Sydney, Ultimo, NSW, 20227, Australia
| | - Sridevi Chigurupati
- Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, Qassim University, Buraydah, 52571, Kingdom of Saudi Arabia.
- Department of Biotechnology, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Saveetha Nagar, Thandalam, Chennai, Tamilnadu, 602105, India.
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5
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Clippinger AK, Naismith TV, Yoo W, Jansen S, Kast D, Hanson PI. IST1 regulates select endosomal recycling pathways. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.31.551359. [PMID: 37577466 PMCID: PMC10418098 DOI: 10.1101/2023.07.31.551359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
ESCRTs (Endosomal Sorting Complex Required for Transport) are a modular set of protein complexes with membrane remodeling activities that include the formation and release of intralumenal vesicles (ILVs) to generate multivesicular endosomes. While most of the 12 ESCRT-III proteins are known to play roles in ILV formation, IST1 has been associated with a wider range of endosomal remodeling events. Here, we extend previous studies of IST1 function in endosomal trafficking and confirm that IST1, along with its binding partner CHMP1B, contributes to scission of early endosomal carriers. Depleting IST1 impaired delivery of transferrin receptor from early/sorting endosomes to the endocytic recycling compartment and instead increased its rapid recycling to the plasma membrane via peripheral endosomes enriched in the clathrin adaptor AP-1. IST1 is also important for export of mannose 6-phosphate receptor from early/sorting endosomes. Examination of IST1 binding partners on endosomes revealed that IST1 interacts with the MIT domain-containing sorting nexin SNX15, a protein previously reported to regulate endosomal recycling. Our kinetic and spatial analyses establish that SNX15 and IST1 occupy a clathrin-containing subdomain on the endosomal perimeter distinct from those previously implicated in cargo retrieval or degradation. Using live-cell microscopy we see that SNX15 and CHMP1B alternately recruit IST1 to this subdomain or the base of endosomal tubules. These findings indicate that IST1 contributes to a subset of recycling pathways from the early/sorting endosome.
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6
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Ganguly A, Sharma R, Boyer NP, Wernert F, Phan S, Boassa D, Parra L, Das U, Caillol G, Han X, Yates JR, Ellisman MH, Leterrier C, Roy S. Clathrin packets move in slow axonal transport and deliver functional payloads to synapses. Neuron 2021; 109:2884-2901.e7. [PMID: 34534453 DOI: 10.1016/j.neuron.2021.08.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 06/10/2021] [Accepted: 08/13/2021] [Indexed: 12/25/2022]
Abstract
In non-neuronal cells, clathrin has established roles in endocytosis, with clathrin cages enclosing plasma membrane infoldings, followed by rapid disassembly and reuse of monomers. However, in neurons, clathrin is conveyed in slow axonal transport over days to weeks, and the underlying transport/targeting mechanisms, mobile cargo structures, and even its precise presynaptic localization and physiologic role are unclear. Combining live imaging, photobleaching/conversion, mass spectrometry, electron microscopy, and super-resolution imaging, we found that unlike in dendrites, where clathrin cages rapidly assemble and disassemble, in axons, clathrin and related proteins organize into stable "transport packets" that are unrelated to endocytosis and move intermittently on microtubules, generating an overall slow anterograde flow. At synapses, multiple clathrin packets abut synaptic vesicle (SV) clusters, and clathrin packets also exchange between synaptic boutons in a microtubule-dependent "superpool." Within synaptic boundaries, clathrin is surprisingly dynamic, continuously exchanging between local clathrin assemblies, and its depletion impairs SV recycling. Our data provide a conceptual framework for understanding clathrin trafficking and presynaptic targeting that has functional implications.
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Affiliation(s)
- Archan Ganguly
- Department of Pathology, University of California, San Diego, La Jolla, CA, USA
| | - Rohan Sharma
- Department of Pathology, University of California, San Diego, La Jolla, CA, USA
| | - Nicholas P Boyer
- Department of Pathology, University of California, San Diego, La Jolla, CA, USA
| | - Florian Wernert
- Aix Marseille Université, CNRS, INP UMR7051, NeuroCyto, Marseille, France
| | - Sébastien Phan
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA; National Center for Microscopy and Imaging Research, University of California, San Diego, La Jolla, CA, USA
| | - Daniela Boassa
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA; National Center for Microscopy and Imaging Research, University of California, San Diego, La Jolla, CA, USA
| | - Leonardo Parra
- Department of Pathology, University of California, San Diego, La Jolla, CA, USA
| | - Utpal Das
- Department of Pathology, University of California, San Diego, La Jolla, CA, USA; Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - Ghislaine Caillol
- Aix Marseille Université, CNRS, INP UMR7051, NeuroCyto, Marseille, France
| | - Xuemei Han
- Department of Cell Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - John R Yates
- Department of Cell Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Mark H Ellisman
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA; National Center for Microscopy and Imaging Research, University of California, San Diego, La Jolla, CA, USA
| | | | - Subhojit Roy
- Department of Pathology, University of California, San Diego, La Jolla, CA, USA; Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA.
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7
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Perdigão C, Barata MA, Burrinha T, Guimas Almeida C. Alzheimer's disease BIN1 coding variants increase intracellular Aβ levels by interfering with BACE1 recycling. J Biol Chem 2021; 297:101056. [PMID: 34375641 PMCID: PMC8413894 DOI: 10.1016/j.jbc.2021.101056] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/29/2021] [Accepted: 08/05/2021] [Indexed: 01/20/2023] Open
Abstract
Genetic studies have identified BIN1 as the second most important risk locus associated with late-onset Alzheimer's disease (LOAD). However, it is unclear how mutation of this locus mechanistically promotes Alzheimer's disease (AD) pathology. Here we show the consequences of two coding variants in BIN1 (rs754834233 and rs138047593), both in terms of intracellular beta-amyloid (iAbeta) accumulation and early endosome enlargement, two interrelated early cytopathological AD phenotypes, supporting their association with LOAD risk. We previously found that Bin1 deficiency potentiates iAbeta production by enabling BACE1 cleavage of the amyloid precursor protein in enlarged early endosomes due to decreased BACE1 recycling. Here, we discovered that the expression of the two LOAD mutant forms of Bin1 does not rescue the iAbeta accumulation and early endosome enlargement induced by Bin1 knockdown and recovered by wild-type Bin1. Moreover, the overexpression of Bin1 mutants, but not wild-type Bin1, increased the iAbeta42 fragment by reducing the recycling of BACE1, which accumulated in early endosomes, recapitulating the phenotype of Bin1 knockdown. We showed that the mutations in Bin1 reduced its interaction with BACE1. The endocytic recycling of transferrin was similarly affected, indicating that Bin1 is a general regulator of endocytic recycling. These data demonstrate that the LOAD-coding variants in Bin1 lead to a loss of function in endocytic recycling, which may be an early causal mechanism of LOAD.
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Affiliation(s)
- Catarina Perdigão
- iNOVA4Health, CEDOC, NOVA Medical School, NMS, Universidade Nova de Lisboa, Lisboa, Portugal
| | - Mariana A Barata
- iNOVA4Health, CEDOC, NOVA Medical School, NMS, Universidade Nova de Lisboa, Lisboa, Portugal
| | - Tatiana Burrinha
- iNOVA4Health, CEDOC, NOVA Medical School, NMS, Universidade Nova de Lisboa, Lisboa, Portugal
| | - Cláudia Guimas Almeida
- iNOVA4Health, CEDOC, NOVA Medical School, NMS, Universidade Nova de Lisboa, Lisboa, Portugal.
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Kell MJ, Ang SF, Pigati L, Halpern A, Fölsch H. Novel function for AP-1B during cell migration. Mol Biol Cell 2020; 31:2475-2493. [PMID: 32816642 PMCID: PMC7851849 DOI: 10.1091/mbc.e20-04-0256] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The epithelial cell-specific clathrin adaptor protein (AP)-1B has a well-established role in polarized sorting of cargos to the basolateral membrane. Here we show that β1 integrin was dependent on AP-1B and its coadaptor, autosomal recessive hypercholesterolemia protein (ARH), for sorting to the basolateral membrane. We further demonstrate an unprecedented role for AP-1B at the basal plasma membrane during collective cell migration of epithelial sheets. During wound healing, expression of AP-1B (and ARH in AP–1B-positive cells) slowed epithelial-cell migration. We show that AP-1B colocalized with β1 integrin in focal adhesions during cell migration using confocal microscopy and total internal reflection fluorescence microscopy on fixed specimens. Further, AP-1B labeling in cell protrusions was distinct from labeling for the endocytic adaptor complex AP-2. Using stochastic optical reconstruction microscopy we identified numerous AP–1B-coated structures at or close to the basal plasma membrane in cell protrusions. In addition, immunoelectron microscopy showed AP-1B in coated pits and vesicles at the plasma membrane during cell migration. Lastly, quantitative real-time reverse transcription PCR analysis of human epithelial-derived cell lines revealed a loss of AP-1B expression in highly migratory metastatic cancer cells suggesting that AP-1B’s novel role at the basal plasma membrane during cell migration might be an anticancer mechanism.
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Affiliation(s)
- Margaret Johnson Kell
- Department of Cell and Developmental Biology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Su Fen Ang
- Department of Cell and Developmental Biology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Lucy Pigati
- Department of Cell and Developmental Biology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Abby Halpern
- Department of Cell and Developmental Biology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Heike Fölsch
- Department of Cell and Developmental Biology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
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9
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The Mechanistic Role of Bridging Integrator 1 (BIN1) in Alzheimer's Disease. Cell Mol Neurobiol 2020; 41:1431-1440. [PMID: 32719966 DOI: 10.1007/s10571-020-00926-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 07/17/2020] [Indexed: 01/18/2023]
Abstract
Alzheimer's disease (AD) is the leading cause of dementia. The majority of AD cases are late-onset, multifactorial cases. Genome-wide association studies have identified more than 30 loci associated with sporadic AD (SAD), one of which is Bridging integrator 1 (BIN1). For the past few years, there has been a consensus that BIN1 is second only to APOE as the strongest genetic risk factor for SAD. Therefore, many researchers have put great effort into studying the mechanism by which BIN1 might be involved in the pathogenetic process of AD. To date, plenty of evidence has shown that BIN1 may participate in several pathways in AD, including tau and amyloid pathology. In addition, BIN1 has been indicated to take part in other relevant pathways such as inflammation, apoptosis, and calcium homeostasis. In this review, we systemically summarize the research progress on how BIN1 participates in the development of AD, with the expectation of providing promising perspectives for future research.
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10
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Abdul-Salam VB, Russomanno G, Chien-Nien C, Mahomed AS, Yates LA, Wilkins MR, Zhao L, Gierula M, Dubois O, Schaeper U, Endruschat J, Wojciak-Stothard B. CLIC4/Arf6 Pathway. Circ Res 2019; 124:52-65. [PMID: 30582444 PMCID: PMC6325770 DOI: 10.1161/circresaha.118.313705] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
RATIONALE Increased expression of CLIC4 (chloride intracellular channel 4) is a feature of endothelial dysfunction in pulmonary arterial hypertension, but its role in disease pathology is not fully understood. OBJECTIVE To identify CLIC4 effectors and evaluate strategies targeting CLIC4 signaling in pulmonary hypertension. METHODS AND RESULTS Proteomic analysis of CLIC4-interacting proteins in human pulmonary artery endothelial cells identified regulators of endosomal trafficking, including Arf6 (ADP ribosylation factor 6) GTPase activating proteins and clathrin, while CLIC4 overexpression affected protein regulators of vesicular trafficking, lysosomal function, and inflammation. CLIC4 reduced BMPRII (bone morphogenetic protein receptor II) expression and signaling as a result of Arf6-mediated reduction in gyrating clathrin and increased lysosomal targeting of the receptor. BMPRII expression was restored by Arf6 siRNA, Arf inhibitor Sec7 inhibitor H3 (SecinH3), and inhibitors of clathrin-mediated endocytosis but was unaffected by chloride channel inhibitor, indanyloxyacetic acid 94 or Arf1 siRNA. The effects of CLIC4 on NF-κB (nuclear factor-kappa B), HIF (hypoxia-inducible factor), and angiogenic response were prevented by Arf6 siRNA and SecinH3. Sugen/hypoxia mice and monocrotaline rats showed elevated expression of CLIC4, activation of Arf6 and NF-κB, and reduced expression of BMPRII in the lung. These changes were established early during disease development. Lung endothelium-targeted delivery of CLIC4 siRNA or treatment with SecinH3 attenuated the disease, reduced CLIC4/Arf activation, and restored BMPRII expression in the lung. Endothelial colony-forming cells from idiopathic pulmonary hypertensive patients showed upregulation of CLIC4 expression and Arf6 activity, suggesting potential importance of this pathway in the human condition. CONCLUSIONS Arf6 is a novel effector of CLIC4 and a new therapeutic target in pulmonary hypertension.
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Affiliation(s)
- Vahitha B Abdul-Salam
- From the Centre for Pharmacology and Therapeutics (V.B.A.-S., G.R., C.C.-N., A.S.M., M.R.W., L.Z., M.G., O.D., B.W.-S.), Department of Medicine, Imperial College London, United Kingdom
| | - Giusy Russomanno
- From the Centre for Pharmacology and Therapeutics (V.B.A.-S., G.R., C.C.-N., A.S.M., M.R.W., L.Z., M.G., O.D., B.W.-S.), Department of Medicine, Imperial College London, United Kingdom
| | - Chen Chien-Nien
- From the Centre for Pharmacology and Therapeutics (V.B.A.-S., G.R., C.C.-N., A.S.M., M.R.W., L.Z., M.G., O.D., B.W.-S.), Department of Medicine, Imperial College London, United Kingdom
| | - Abdul S Mahomed
- From the Centre for Pharmacology and Therapeutics (V.B.A.-S., G.R., C.C.-N., A.S.M., M.R.W., L.Z., M.G., O.D., B.W.-S.), Department of Medicine, Imperial College London, United Kingdom
| | - Luke A Yates
- Section of Structural Biology (L.A.Y.), Department of Medicine, Imperial College London, United Kingdom
| | - Martin R Wilkins
- From the Centre for Pharmacology and Therapeutics (V.B.A.-S., G.R., C.C.-N., A.S.M., M.R.W., L.Z., M.G., O.D., B.W.-S.), Department of Medicine, Imperial College London, United Kingdom
| | - Lan Zhao
- From the Centre for Pharmacology and Therapeutics (V.B.A.-S., G.R., C.C.-N., A.S.M., M.R.W., L.Z., M.G., O.D., B.W.-S.), Department of Medicine, Imperial College London, United Kingdom
| | - Magdalena Gierula
- From the Centre for Pharmacology and Therapeutics (V.B.A.-S., G.R., C.C.-N., A.S.M., M.R.W., L.Z., M.G., O.D., B.W.-S.), Department of Medicine, Imperial College London, United Kingdom
| | - Oliver Dubois
- From the Centre for Pharmacology and Therapeutics (V.B.A.-S., G.R., C.C.-N., A.S.M., M.R.W., L.Z., M.G., O.D., B.W.-S.), Department of Medicine, Imperial College London, United Kingdom
| | - Ute Schaeper
- Silence Therapeutics GmbH, Berlin, Germany (U.S., J.E.)
| | | | - Beata Wojciak-Stothard
- From the Centre for Pharmacology and Therapeutics (V.B.A.-S., G.R., C.C.-N., A.S.M., M.R.W., L.Z., M.G., O.D., B.W.-S.), Department of Medicine, Imperial College London, United Kingdom
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11
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Tower-Gilchrist C, Zlatic SA, Yu D, Chang Q, Wu H, Lin X, Faundez V, Chen P. Adaptor protein-3 complex is required for Vangl2 trafficking and planar cell polarity of the inner ear. Mol Biol Cell 2019; 30:2422-2434. [PMID: 31268833 PMCID: PMC6741063 DOI: 10.1091/mbc.e16-08-0592] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Planar cell polarity (PCP) regulates coordinated cellular polarity among neighboring cells to establish a polarity axis parallel to the plane of the tissue. Disruption in PCP results in a range of developmental anomalies and diseases. A key feature of PCP is the polarized and asymmetric localization of several membrane PCP proteins, which is essential to establish the polarity axis to orient cells coordinately. However, the machinery that regulates the asymmetric partition of PCP proteins remains largely unknown. In the present study, we show Van gogh-like 2 (Vangl2) in early and recycling endosomes as made evident by colocalization with diverse endosomal Rab proteins. Vangl2 biochemically interacts with adaptor protein-3 complex (AP-3). Using short hairpin RNA knockdown, we found that Vangl2 subcellular localization was modified in AP-3–depleted cells. Moreover, Vangl2 membrane localization within the cochlea is greatly reduced in AP-3–deficient mocha mice, which exhibit profound hearing loss. In inner ears from AP-3–deficient mocha mice, we observed PCP-dependent phenotypes, such as misorientation and deformation of hair cell stereociliary bundles and disorganization of hair cells characteristic of defects in convergent extension that is driven by PCP. These findings demonstrate a novel role of AP-3–mediated sorting mechanisms in regulating PCP proteins.
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Affiliation(s)
| | - Stephanie A Zlatic
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322
| | - Dehong Yu
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322.,Department of Otolaryngology-Head and Neck Surgery, Xinhua Hospital and Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai 200125, China
| | - Qing Chang
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322.,Department of Otolaryngology, Emory University School of Medicine, Atlanta, GA 30322
| | - Hao Wu
- Department of Otolaryngology-Head and Neck Surgery, Xinhua Hospital and Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai 200125, China
| | - Xi Lin
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322.,Department of Otolaryngology, Emory University School of Medicine, Atlanta, GA 30322
| | - Victor Faundez
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322
| | - Ping Chen
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322
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12
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Sahgal P, Alanko J, Icha J, Paatero I, Hamidi H, Arjonen A, Pietilä M, Rokka A, Ivaska J. GGA2 and RAB13 promote activity-dependent β1-integrin recycling. J Cell Sci 2019; 132:jcs.233387. [PMID: 31076515 DOI: 10.1242/jcs.233387] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 04/21/2019] [Indexed: 12/27/2022] Open
Abstract
β1-integrins mediate cell-matrix interactions and their trafficking is important in the dynamic regulation of cell adhesion, migration and malignant processes, including cancer cell invasion. Here, we employ an RNAi screen to characterize regulators of integrin traffic and identify the association of Golgi-localized gamma ear-containing Arf-binding protein 2 (GGA2) with β1-integrin, and its role in recycling of active but not inactive β1-integrin receptors. Silencing of GGA2 limits active β1-integrin levels in focal adhesions and decreases cancer cell migration and invasion, which is in agreement with its ability to regulate the dynamics of active integrins. By using the proximity-dependent biotin identification (BioID) method, we identified two RAB family small GTPases, i.e. RAB13 and RAB10, as novel interactors of GGA2. Functionally, RAB13 silencing triggers the intracellular accumulation of active β1-integrin, and reduces integrin activity in focal adhesions and cell migration similarly to GGA2 depletion, indicating that both facilitate active β1-integrin recycling to the plasma membrane. Thus, GGA2 and RAB13 are important specificity determinants for integrin activity-dependent traffic.
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Affiliation(s)
- Pranshu Sahgal
- Turku Bioscience Centre, University of Turku and Åbo Akademi University, Turku FIN-20520, Finland
| | - Jonna Alanko
- Turku Bioscience Centre, University of Turku and Åbo Akademi University, Turku FIN-20520, Finland
| | - Jaroslav Icha
- Turku Bioscience Centre, University of Turku and Åbo Akademi University, Turku FIN-20520, Finland
| | - Ilkka Paatero
- Turku Bioscience Centre, University of Turku and Åbo Akademi University, Turku FIN-20520, Finland
| | - Hellyeh Hamidi
- Turku Bioscience Centre, University of Turku and Åbo Akademi University, Turku FIN-20520, Finland
| | - Antti Arjonen
- Turku Bioscience Centre, University of Turku and Åbo Akademi University, Turku FIN-20520, Finland
| | - Mika Pietilä
- Turku Bioscience Centre, University of Turku and Åbo Akademi University, Turku FIN-20520, Finland
| | - Anne Rokka
- Turku Bioscience Centre, University of Turku and Åbo Akademi University, Turku FIN-20520, Finland
| | - Johanna Ivaska
- Turku Bioscience Centre, University of Turku and Åbo Akademi University, Turku FIN-20520, Finland .,Department of Biochemistry and Food Chemistry, University of Turku, Turku FIN-20520, Finland
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13
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Tsygankova OM, Keen JH. A unique role for clathrin light chain A in cell spreading and migration. J Cell Sci 2019; 132:jcs.224030. [PMID: 30975920 DOI: 10.1242/jcs.224030] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Accepted: 04/01/2019] [Indexed: 12/12/2022] Open
Abstract
Clathrin heavy chain is the structural component of the clathrin triskelion, but unique functions for the two distinct and highly conserved clathrin light chains (CLCa and CLCb, also known as CLTA and CLTB, respectively) have been elusive. Here, we show that following detachment and replating, CLCa is uniquely responsible for promoting efficient cell spreading and migration. Selective depletion of CLCa, but not of CLCb, reduced the initial phase of isotropic spreading of HeLa, H1299 and HEK293 cells by 60-80% compared to siRNA controls, and wound closure and motility by ∼50%. Surface levels of β1-integrins were unaffected by CLCa depletion. However, CLCa was required for effective targeting of FAK (also known as PTK2) and paxillin to the adherent surface of spreading cells, for integrin-mediated activation of Src, FAK and paxillin, and for maturation of focal adhesions, but not their microtubule-based turnover. Depletion of CLCa also blocked the interaction of clathrin with the nucleation-promoting factor WAVE complex, and altered actin distribution. Furthermore, preferential recruitment of CLCa to budding protrusions was also observed. These results comprise the first identification of CLCa-specific functions, with implications for normal and neoplastic integrin-based signaling and cell migration.
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Affiliation(s)
- Oxana M Tsygankova
- Department of Biochemistry and Molecular Biology, Cell Biology and Signaling Program of the Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - James H Keen
- Department of Biochemistry and Molecular Biology, Cell Biology and Signaling Program of the Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
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14
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Abstract
The entry of pathogens into nonphagocytic host cells has received much attention in the past three decades, revealing a vast array of strategies employed by bacteria and viruses. A method of internalization that has been extensively studied in the context of viral infections is the use of the clathrin-mediated pathway. More recently, a role for clathrin in the entry of some intracellular bacterial pathogens was discovered. Classically, clathrin-mediated endocytosis was thought to accommodate internalization only of particles smaller than 150 nm; however, this was challenged upon the discovery that Listeria monocytogenes requires clathrin to enter eukaryotic cells. Now, with discoveries that clathrin is required during other stages of some bacterial infections, another paradigm shift is occurring. There is a more diverse impact of clathrin during infection than previously thought. Much of the recent data describing clathrin utilization in processes such as bacterial attachment, cell-to-cell spread and intracellular growth may be due to newly discovered divergent roles of clathrin in the cell. Not only does clathrin act to facilitate endocytosis from the plasma membrane, but it also participates in budding from endosomes and the Golgi apparatus and in mitosis. Here, the manipulation of clathrin processes by bacterial pathogens, including its traditional role during invasion and alternative ways in which clathrin supports bacterial infection, is discussed. Researching clathrin in the context of bacterial infections will reveal new insights that inform our understanding of host-pathogen interactions and allow researchers to fully appreciate the diverse roles of clathrin in the eukaryotic cell.
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15
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Lambert L, Dubayle D, Fafouri A, Herzog E, Csaba Z, Dournaud P, El Mestikawy S, Bernard V. Endocytosis of Activated Muscarinic m2 Receptor (m2R) in Live Mouse Hippocampal Neurons Occurs via a Clathrin-Dependent Pathway. Front Cell Neurosci 2018; 12:450. [PMID: 30555302 PMCID: PMC6283979 DOI: 10.3389/fncel.2018.00450] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 11/07/2018] [Indexed: 02/02/2023] Open
Abstract
Our aim was to examine the dynamics of the muscarinic m2 receptor (m2R), a G-protein coupled receptor (GPCR), after agonist activation in living hippocampal neurons, and especially clathrin dependency endocytosis. We have previously shown that the m2R undergoes agonist-induced internalization in vivo. However, the nature of the endocytotic pathway used by m2R after activation is still unknown in living neurons. Using live cell imaging and quantitative analyses, we have monitored the effect of stimulation on the fate of the membrane-bound m2R and on its redistribution in intraneuronal compartments. Shortly (6 min) after activation, m2R is internalized into clathrin immunopositive structures. Furthermore, after clathrin-dependent endocytosis, m2R associates with early and late endosomes and with subcellular organelles involved in degradation. Together, these results provide, for the first time, a description of m2R trafficking in living neurons and prove that m2R undergoes clathrin-dependent endocytosis before being degraded.
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Affiliation(s)
- Lisa Lambert
- Sorbonne Université, Université Pierre et Marie Curie UM 119 - CNRS UMR 8246 - INSERM U1130, Neurosciences Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS), Paris, France
| | - David Dubayle
- Sorbonne Université, Université Pierre et Marie Curie UM 119 - CNRS UMR 8246 - INSERM U1130, Neurosciences Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS), Paris, France.,Université Paris Descartes - CNRS UMR 8119, Centre de Neurophysique, Physiologie et Pathologie, Paris, France
| | - Assia Fafouri
- PROTECT, INSERM U1141, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Etienne Herzog
- Sorbonne Université, Université Pierre et Marie Curie UM 119 - CNRS UMR 8246 - INSERM U1130, Neurosciences Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS), Paris, France.,Interdisciplinary Institute for Neuroscience, University Bordeaux, UMR 5297, Bordeaux, France.,Interdisciplinary Institute for Neuroscience, CNRS, UMR 5297, Bordeaux, France
| | - Zsolt Csaba
- PROTECT, INSERM U1141, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Pascal Dournaud
- PROTECT, INSERM U1141, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Salah El Mestikawy
- Sorbonne Université, Université Pierre et Marie Curie UM 119 - CNRS UMR 8246 - INSERM U1130, Neurosciences Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS), Paris, France.,Department of Psychiatry, Douglas Hospital Research Center, McGill University, Montréal, QC, Canada
| | - Véronique Bernard
- Sorbonne Université, Université Pierre et Marie Curie UM 119 - CNRS UMR 8246 - INSERM U1130, Neurosciences Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS), Paris, France
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16
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GGA2 interacts with EGFR cytoplasmic domain to stabilize the receptor expression and promote cell growth. Sci Rep 2018; 8:1368. [PMID: 29358589 PMCID: PMC5778047 DOI: 10.1038/s41598-018-19542-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 01/03/2018] [Indexed: 12/29/2022] Open
Abstract
Epidermal growth factor receptor (EGFR) signaling and its downregulation upon ligand binding have been extensively documented. However, the mechanisms by which cells maintain steady-state EGFR expression remain poorly understood. Here, we report a novel role of Golgi-localized, γ-adaptin ear-containing, ADP ribosylation factor-binding protein 2 (GGA2) in the control of EGFR turnover. Whereas GGA1- or GGA3-depletion increased EGFR expression, GGA2-depletion by RNAi greatly reduced steady-state expression of EGFR, reflecting enhanced lysosomal degradation of EGFR. Subsequent pull-down assays showed interactions of VHS-GAT domains from three GGAs with the cytoplasmic juxtamembrane region (jxt) of EGFR, which was dependent on N108 in the VHS domain. Proximity ligation assay also revealed the steady-state interaction between GGA2 and EGFR in situ. Moreover, reduced expression of EGFR in GGA2-depleted cells was reversed by additional depletion of GGA1 or GGA3, suggesting that GGA1 and GGA3 promote EGFR degradation. In addition, GGA2-depleted cells had reduced EGF signaling and cell proliferation in cell culture and xenograft experiments. Finally, GGA2 was upregulated in 30.8% of human hepatocellular carcinomas and 23.3% of colorectal cancers. Together, these results indicate that GGA2 supports cell growth by interacting with EGFR for sustaining the receptor expression.
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17
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Janickova H, Prado VF, Prado MAM, El Mestikawy S, Bernard V. Vesicular acetylcholine transporter (VAChT) over-expression induces major modifications of striatal cholinergic interneuron morphology and function. J Neurochem 2017. [DOI: 10.1111/jnc.14105] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Helena Janickova
- Department of Physiology and Pharmacology and Department of Anatomy & Cell Biology; Robarts Research Institute; Molecular Medicine Laboratories; The University of Western Ontario; London Ontario Canada
| | - Vania F. Prado
- Department of Physiology and Pharmacology and Department of Anatomy & Cell Biology; Robarts Research Institute; Molecular Medicine Laboratories; The University of Western Ontario; London Ontario Canada
| | - Marco A. M. Prado
- Department of Physiology and Pharmacology and Department of Anatomy & Cell Biology; Robarts Research Institute; Molecular Medicine Laboratories; The University of Western Ontario; London Ontario Canada
| | - Salah El Mestikawy
- Sorbonne Universités; Université Pierre et Marie Curie UM 119 - CNRS UMR 8246 - INSERM U1130; Neurosciences Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS); Paris France
- Department of Psychiatry; Douglas Mental Health University Institute; McGill University; Montreal Canada
| | - Véronique Bernard
- Sorbonne Universités; Université Pierre et Marie Curie UM 119 - CNRS UMR 8246 - INSERM U1130; Neurosciences Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS); Paris France
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18
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Ubelmann F, Burrinha T, Salavessa L, Gomes R, Ferreira C, Moreno N, Guimas Almeida C. Bin1 and CD2AP polarise the endocytic generation of beta-amyloid. EMBO Rep 2016; 18:102-122. [PMID: 27895104 DOI: 10.15252/embr.201642738] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 10/14/2016] [Accepted: 10/19/2016] [Indexed: 01/31/2023] Open
Abstract
The mechanisms driving pathological beta-amyloid (Aβ) generation in late-onset Alzheimer's disease (AD) are unclear. Two late-onset AD risk factors, Bin1 and CD2AP, are regulators of endocytic trafficking, but it is unclear how their endocytic function regulates Aβ generation in neurons. We identify a novel neuron-specific polarisation of Aβ generation controlled by Bin1 and CD2AP We discover that Bin1 and CD2AP control Aβ generation in axonal and dendritic early endosomes, respectively. Both Bin1 loss of function and CD2AP loss of function raise Aβ generation by increasing APP and BACE1 convergence in early endosomes, however via distinct sorting events. When Bin1 levels are reduced, BACE1 is trapped in tubules of early endosomes and fails to recycle in axons. When CD2AP levels are reduced, APP is trapped at the limiting membrane of early endosomes and fails to be sorted for degradation in dendrites. Hence, Bin1 and CD2AP keep APP and BACE1 apart in early endosomes by distinct mechanisms in axon and dendrites. Individuals carrying variants of either factor would slowly accumulate Aβ in neurons increasing the risk for late-onset AD.
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Affiliation(s)
- Florent Ubelmann
- Neuronal Trafficking in Aging Lab, CEDOC, Chronic Diseases Research Centre, NOVA Medical School/Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Lisboa, Portugal
| | - Tatiana Burrinha
- Neuronal Trafficking in Aging Lab, CEDOC, Chronic Diseases Research Centre, NOVA Medical School/Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Lisboa, Portugal
| | - Laura Salavessa
- Neuronal Trafficking in Aging Lab, CEDOC, Chronic Diseases Research Centre, NOVA Medical School/Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Lisboa, Portugal
| | - Ricardo Gomes
- Neuronal Trafficking in Aging Lab, CEDOC, Chronic Diseases Research Centre, NOVA Medical School/Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Lisboa, Portugal
| | - Cláudio Ferreira
- Neuronal Trafficking in Aging Lab, CEDOC, Chronic Diseases Research Centre, NOVA Medical School/Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Lisboa, Portugal
| | - Nuno Moreno
- Advance Imaging Lab, Instituto Gulbenkian de Ciência, Oeiras, Portugal
| | - Cláudia Guimas Almeida
- Neuronal Trafficking in Aging Lab, CEDOC, Chronic Diseases Research Centre, NOVA Medical School/Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Lisboa, Portugal
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19
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Ye QH, Zhu WW, Zhang JB, Qin Y, Lu M, Lin GL, Guo L, Zhang B, Lin ZH, Roessler S, Forgues M, Jia HL, Lu L, Zhang XF, Lian BF, Xie L, Dong QZ, Tang ZY, Wang XW, Qin LX. GOLM1 Modulates EGFR/RTK Cell-Surface Recycling to Drive Hepatocellular Carcinoma Metastasis. Cancer Cell 2016; 30:444-458. [PMID: 27569582 PMCID: PMC5021625 DOI: 10.1016/j.ccell.2016.07.017] [Citation(s) in RCA: 157] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2014] [Revised: 06/27/2016] [Accepted: 07/26/2016] [Indexed: 12/11/2022]
Abstract
The mechanism of cancer metastasis remains poorly understood. Using gene profiling of hepatocellular carcinoma (HCC) tissues, we have identified GOLM1 as a leading gene relating to HCC metastasis. GOLM1 expression is correlated with early recurrence, metastasis, and poor survival of HCC patients. Both gain- and loss-of-function studies determine that GOLM1 acts as a key oncogene by promoting HCC growth and metastasis. It selectively interacts with epidermal growth factor receptor (EGFR) and serves as a specific cargo adaptor to assist EGFR/RTK anchoring on the trans-Golgi network (TGN) and recycling back to the plasma membrane, leading to prolonged activation of the downstream kinases. These findings reveal the functional role of GOLM1, a Golgi-related protein, in EGFR/RTK recycling and metastatic progression of HCC.
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Affiliation(s)
- Qing-Hai Ye
- Liver Cancer Institute, Fudan University, Shanghai 200032, China
| | - Wen-Wei Zhu
- Liver Cancer Institute, Fudan University, Shanghai 200032, China; Department of General Surgery, Huashan Hospital, Cancer Metastasis Institute, Fudan University, 12 Urumqi Road (M), Shanghai 200040, China
| | - Ju-Bo Zhang
- Liver Cancer Institute, Fudan University, Shanghai 200032, China; Department of Infectious Diseases, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Yi Qin
- Institutes of Biomedical Science, Fudan University, Shanghai 200032, China; Department of Pancreatic and Hepatobiliary Surgery, Fudan University Shanghai Cancer Center, Shanghai 200032, China
| | - Ming Lu
- Department of General Surgery, Huashan Hospital, Cancer Metastasis Institute, Fudan University, 12 Urumqi Road (M), Shanghai 200040, China
| | - Guo-Ling Lin
- Liver Cancer Institute, Fudan University, Shanghai 200032, China
| | - Lei Guo
- Liver Cancer Institute, Fudan University, Shanghai 200032, China
| | - Bo Zhang
- Liver Cancer Institute, Fudan University, Shanghai 200032, China
| | - Zhen-Hai Lin
- Liver Cancer Institute, Fudan University, Shanghai 200032, China
| | - Stephanie Roessler
- Laboratory of Human Carcinogenesis, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA; Institute of Pathology, University Hospital Heidelberg 69120 Heidelberg, Germany
| | - Marshonna Forgues
- Laboratory of Human Carcinogenesis, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Hu-Liang Jia
- Department of General Surgery, Huashan Hospital, Cancer Metastasis Institute, Fudan University, 12 Urumqi Road (M), Shanghai 200040, China
| | - Lu Lu
- Department of General Surgery, Huashan Hospital, Cancer Metastasis Institute, Fudan University, 12 Urumqi Road (M), Shanghai 200040, China
| | - Xiao-Fei Zhang
- Department of General Surgery, Huashan Hospital, Cancer Metastasis Institute, Fudan University, 12 Urumqi Road (M), Shanghai 200040, China
| | - Bao-Feng Lian
- Shanghai Center for Bioinformatics Technology, Shanghai 201203, China
| | - Lu Xie
- Shanghai Center for Bioinformatics Technology, Shanghai 201203, China
| | - Qiong-Zhu Dong
- Department of General Surgery, Huashan Hospital, Cancer Metastasis Institute, Fudan University, 12 Urumqi Road (M), Shanghai 200040, China; Institutes of Biomedical Science, Fudan University, Shanghai 200032, China
| | - Zhao-You Tang
- Liver Cancer Institute, Fudan University, Shanghai 200032, China; Department of General Surgery, Huashan Hospital, Cancer Metastasis Institute, Fudan University, 12 Urumqi Road (M), Shanghai 200040, China
| | - Xin Wei Wang
- Laboratory of Human Carcinogenesis, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA.
| | - Lun-Xiu Qin
- Liver Cancer Institute, Fudan University, Shanghai 200032, China; Department of General Surgery, Huashan Hospital, Cancer Metastasis Institute, Fudan University, 12 Urumqi Road (M), Shanghai 200040, China; Institutes of Biomedical Science, Fudan University, Shanghai 200032, China.
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20
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Ratcliffe CDH, Sahgal P, Parachoniak CA, Ivaska J, Park M. Regulation of Cell Migration and β1 Integrin Trafficking by the Endosomal Adaptor GGA3. Traffic 2016; 17:670-88. [PMID: 26935970 DOI: 10.1111/tra.12390] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 02/29/2016] [Accepted: 02/29/2016] [Indexed: 12/27/2022]
Abstract
The integrin family of cell adhesion receptors link extracellular matrices to intracellular signaling pathways and the actin cytoskeleton; and regulate cell migration, proliferation and survival in normal and diseased tissues. The subcellular location of integrin receptors is critical for their function and deregulated trafficking is implicated in various human diseases. Here we identify a role for Golgi-localized gamma-ear containing Arf-binding protein 3 (GGA3), in regulating trafficking of β1 integrin. GGA3 knockdown reduces cell surface and total levels of α2, α5 and β1 integrin subunits, inhibits cell spreading, reduces focal adhesion number, as well as cell migration. In the absence of GGA3, integrins are increasingly retained inside the cell, traffic toward the perinuclear lysosomal compartment and their degradation is enhanced. Integrin traffic and maintenance of integrin levels are dependent on the integrity of the Arf binding site of GGA3. Furthermore, sorting nexin 17 (SNX17), a critical regulator of integrin recycling, becomes mislocalized to enlarged late endosomes upon GGA3 depletion. These data support a model whereby GGA3, through its ability to regulate SNX17 endosomal localization and through interaction with Arf6 diverts integrins from the degradative pathway supporting cell migration.
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Affiliation(s)
- Colin D H Ratcliffe
- Department of Biochemistry, McGill University, Montreal, Quebec, H3G 1Y6, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Quebec, H3A 1A3, Canada
| | - Pranshu Sahgal
- Turku Centre for Biotechnology, University of Turku, Turku, 20520, Finland
| | - Christine A Parachoniak
- Department of Biochemistry, McGill University, Montreal, Quebec, H3G 1Y6, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Quebec, H3A 1A3, Canada
| | - Johanna Ivaska
- Turku Centre for Biotechnology, University of Turku, Turku, 20520, Finland
- Department of Biochemistry and Food Chemistry, University of Turku, Turku, 20500, Finland
| | - Morag Park
- Department of Biochemistry, McGill University, Montreal, Quebec, H3G 1Y6, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Quebec, H3A 1A3, Canada
- Department of Medicine, McGill University, Montreal, Quebec, H3G 1Y6, Canada
- Department of Oncology, McGill University, Montreal, Quebec, H3G 1Y6, Canada
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21
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Regulation of Notch Signaling Through Intracellular Transport. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2016; 323:107-27. [PMID: 26944620 DOI: 10.1016/bs.ircmb.2015.12.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The highly conserved Notch-signaling pathway performs a central role in cell differentiation, survival, and proliferation. A major mechanism by which cells modulate signaling is by controlling the intracellular transport itinerary of Notch. Indeed, Notch removal from the cell surface and its targeting to the lysosome for degradation is one way in which Notch activity is downregulated since it limits receptor exposure to ligand. In contrast, Notch-signaling capacity is maintained through repeated rounds of receptor recycling and redelivery of Notch to the cell surface from endosomal stores. This review discusses the molecular mechanisms by which Notch transit through the endosome is controlled and how various intracellular sorting decisions are thought to impact signaling activity.
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22
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Hong SH, Cortesio CL, Drubin DG. Machine-Learning-Based Analysis in Genome-Edited Cells Reveals the Efficiency of Clathrin-Mediated Endocytosis. Cell Rep 2015; 12:2121-30. [PMID: 26387943 DOI: 10.1016/j.celrep.2015.08.048] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 06/05/2015] [Accepted: 08/17/2015] [Indexed: 12/30/2022] Open
Abstract
Cells internalize various molecules through clathrin-mediated endocytosis (CME). Previous live-cell imaging studies suggested that CME is inefficient, with about half of the events terminated. These CME efficiency estimates may have been confounded by overexpression of fluorescently tagged proteins and inability to filter out false CME sites. Here, we employed genome editing and machine learning to identify and analyze authentic CME sites. We examined CME dynamics in cells that express fluorescent fusions of two defining CME proteins, AP2 and clathrin. Support vector machine classifiers were built to identify and analyze authentic CME sites. From inception until disappearance, authentic CME sites contain both AP2 and clathrin, have the same degree of limited mobility, continue to accumulate AP2 and clathrin over lifetimes >∼20 s, and almost always form vesicles as assessed by dynamin2 recruitment. Sites that contain only clathrin or AP2 show distinct dynamics, suggesting they are not part of the CME pathway.
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Affiliation(s)
- Sun Hae Hong
- Department of Molecular and Cell Biology, University of California-Berkeley, Berkeley, CA 94720, USA
| | - Christa L Cortesio
- Department of Molecular and Cell Biology, University of California-Berkeley, Berkeley, CA 94720, USA
| | - David G Drubin
- Department of Molecular and Cell Biology, University of California-Berkeley, Berkeley, CA 94720, USA.
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23
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Clathrin light chains are required for the gyrating-clathrin recycling pathway and thereby promote cell migration. Nat Commun 2014; 5:3891. [PMID: 24852344 PMCID: PMC4050264 DOI: 10.1038/ncomms4891] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2014] [Accepted: 04/14/2014] [Indexed: 02/07/2023] Open
Abstract
The clathrin light chain (CLC) subunits participate in several membrane traffic pathways involving both clathrin and actin, through binding the actin-organizing huntingtin-interacting proteins (Hip). However, CLCs are dispensable for clathrin-mediated endocytosis of many cargoes. Here we observe that CLC depletion affects cell migration through Hip binding and reduces surface expression of β1-integrin by interference with recycling following normal endocytosis of inactive β1-integrin. CLC depletion and expression of a modified CLC also inhibit the appearance of gyrating (G)-clathrin structures, known mediators of rapid recycling of transferrin receptor from endosomes. Expression of the modified CLC reduces β1-integrin and transferrin receptor recycling, as well as cell migration, implicating G-clathrin in these processes. Supporting a physiological role for CLC in migration, the CLCb isoform of CLC is upregulated in migratory human trophoblast cells during uterine invasion. Together, these studies establish CLCs as mediating clathrin–actin interactions needed for recycling by G-clathrin during migration. Clathrin light chain (CLC) subunits are dispensable for clathrin-mediated endocytosis of a number of cargoes. Majeed et al. report that CLCs are however required for gyrating-clathrin-dependent recycling of inactive β1-integrins, the absence of which impairs cell migration.
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Abstract
Arrestins are adaptor proteins that function to regulate G protein-coupled receptor (GPCR) signaling and trafficking. There are four mammalian members of the arrestin family, two visual and two nonvisual. The visual arrestins (arrestin-1 and arrestin-4) are localized in rod and cone cells, respectively, and function to quench phototransduction by inhibiting receptor/G protein coupling. The nonvisual arrestins (β-arrestin1 and β-arrestin2, a.k.a. arrestin-2 and arrestin-3) are ubiquitously expressed and function to inhibit GPCR/G protein coupling and promote GPCR trafficking and arrestin-mediated signaling. Arrestin-mediated endocytosis of GPCRs requires the coordinated interaction of β-arrestins with clathrin, adaptor protein 2, and phosphoinositides such as PIP(2)/PIP(3). These interactions are facilitated by a conformational change in β-arrestin that is thought to occur upon binding to a phosphorylated activated GPCR. In this chapter, we provide an overview of the reagents and techniques used to study β-arrestin-mediated receptor trafficking.
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Affiliation(s)
- Dong Soo Kang
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
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Balasubramanian S, Kota SK, Kuchroo VK, Humphreys BD, Strom TB. TIM family proteins promote the lysosomal degradation of the nuclear receptor NUR77. Sci Signal 2012; 5:ra90. [PMID: 23233528 DOI: 10.1126/scisignal.2003200] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
T cell immunoglobulin and mucin domain (TIM) proteins are cell-surface signaling receptors in T cells and scavenger receptors in antigen-presenting cells and kidney tubular epithelia. Here, we demonstrated a function for TIM proteins in mediating the degradation of NUR77, a nuclear receptor implicated in apoptosis and cell survival. TIM proteins interacted with and mediated the lysosomal degradation of NUR77 in a phosphoinositide 3-kinase-dependent pathway. We also showed dynamic cycling of TIM-1 to and from the cell surface through clathrin-dependent constitutive endocytosis. Blocking this process or mutating the phosphatidylserine-binding pocket in TIM-1 abrogated TIM-1-mediated degradation of NUR77. In an in vitro model of kidney injury, silencing TIM-1 increased NUR77 abundance and decreased epithelial cell survival. These results show that TIM proteins may affect immune cell function and the response of the kidney to injury.
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Affiliation(s)
- Savithri Balasubramanian
- Harvard Medical School, Department of Medicine, The Transplant Institute, Beth Israel Deaconess Medical Center, Boston, MA 02115, USA.
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Luo Y, Zhan Y, Keen JH. Arf6 regulation of Gyrating-clathrin. Traffic 2012; 14:97-106. [PMID: 22998223 DOI: 10.1111/tra.12014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Revised: 09/19/2012] [Accepted: 09/21/2012] [Indexed: 11/29/2022]
Abstract
'Gyrating-' or 'G'-clathrin are coated endocytic structures located near peripheral sorting endosomes (SEs), which exhibit highly dynamic but localized movements when visualized by live-cell microscopy. They have been implicated in recycling of transferrin from the sorting endosome directly to the cell surface, but there is no information about their formation or regulation. We show here that G-clathrin comprise a minority of clathrin-coated structures in the cell periphery and are brefeldin A (BFA)-resistant. Arf6-GTP substantially increases G-clathrin levels, probably by lengthening coated bud lifetimes as suggested by photobleaching and photoactivation results, and an Arf6(Q67L)-GTP mutant bearing an internal GFP tag can be directly visualized in G-clathrin structures in live cells. Upon siRNA-mediated depletion of Arf6 or expression of Arf6(T27N), G-clathrin levels rise and are primarily Arf1-dependent, yet still BFA-resistant. However, BFA-sensitive increased G-clathrin levels are observed upon acute incubation with cytohesin inhibitor SecinH3, indicating a shift in GEF usage. Depletion of both Arf6 and Arf1 abolishes G-clathrin, and results in partial inhibition of fast transferrin recycling consistent with the latter's participation in this pathway. Collectively, these results demonstrate that the dynamics of G-clathrin primarily requires completion of the Arf6 guanine nucleotide cycle, but can be regulated by multiple Arf and GEF proteins, reflecting both overlapping mechanisms operative in their regulation and the complexity of processes involved in endosomal sorting.
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Affiliation(s)
- Yi Luo
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
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27
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Runyan CE, Liu Z, Schnaper HW. Phosphatidylinositol 3-kinase and Rab5 GTPase inversely regulate the Smad anchor for receptor activation (SARA) protein independently of transforming growth factor-β1. J Biol Chem 2012; 287:35815-24. [PMID: 22942286 DOI: 10.1074/jbc.m112.380493] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
SARA has been shown to be a regulator of epithelial cell phenotype, with reduced expression during TGF-β1-mediated epithelial-to-mesenchymal transition. Examination of the pathways that might play a role in regulating SARA expression identified phosphatidylinositol 3-kinase (PI3K) pathway inhibition as sufficient to reduce SARA expression. The mechanism of PI3K inhibition-mediated SARA down-regulation differs from that induced by TGF-β1 in that, unlike TGF-β1, PI3K-dependent depletion of SARA was apparent within 6 h and did not occur at the mRNA or promoter level but was blocked by inhibition of proteasome-mediated degradation. This effect was independent of Akt activity because neither reducing nor enhancing Akt activity modulated the expression of SARA. Therefore, this is likely a direct effect of p85α action, and co-immunoprecipitation of SARA and p85α confirmed that these proteins interact. Both SARA and PI3K have been shown to be associated with endosomes, and either LY294002 or p85α knockdown enlarged SARA-containing endocytic vesicles. Inhibition of clathrin-mediated endocytosis blocked SARA down-regulation, and a localization-deficient mutant SARA was protected against down-regulation. As inhibiting PI3K can activate the endosomal fusion-regulatory small GTPase Rab5, we expressed GTPase-deficient Rab5 and observed endosomal enlargement and reduced SARA protein expression, similar to that seen with PI3K inhibition. Importantly, either interference with PI3K via LY294002 or p85α knockdown, or constitutive activity of the Rab5 pathway, enhanced the expression of smooth muscle α-actin. Together, these data suggest that although TGF-β1 can induce epithelial-to-mesenchymal transition through reduction in SARA expression, SARA is also basally regulated by its interaction with PI3K.
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Affiliation(s)
- Constance E Runyan
- Department of Pediatrics, Northwestern University, Chicago, Illinois 60611, USA.
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28
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Abstract
Clathrin is considered the prototype vesicle coat protein whose self-assembly mediates sorting of membrane cargo and recruitment of lipid modifiers. Detailed knowledge of clathrin biochemistry, structure, and interacting proteins has accumulated since the first observation, almost 50 years ago, of its role in receptor-mediated endocytosis of yolk protein. This review summarizes that knowledge, and focuses on properties of the clathrin heavy and light chain subunits and interaction of the latter with Hip proteins, to address the diversity of clathrin function beyond conventional receptor-mediated endocytosis. The distinct functions of the two human clathrin isoforms (CHC17 and CHC22) are discussed, highlighting CHC22's specialized involvement in traffic of the GLUT4 glucose transporter and consequent role in human glucose metabolism. Analysis of clathrin light chain function and interaction with the actin-binding Hip proteins during bacterial infection defines a novel actin-organizing function for CHC17 clathrin. By considering these diverse clathrin functions, along with intracellular sorting roles and influences on mitosis, further relevance of clathrin function to human health and disease is established.
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Affiliation(s)
- Frances M Brodsky
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, California 94143-0552, USA.
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29
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Dynamics of receptor trafficking in tumorigenicity. Trends Cell Biol 2012; 22:231-40. [DOI: 10.1016/j.tcb.2012.02.002] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Revised: 02/01/2012] [Accepted: 02/07/2012] [Indexed: 02/07/2023]
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Parachoniak CA, Luo Y, Abella JV, Keen JH, Park M. GGA3 functions as a switch to promote Met receptor recycling, essential for sustained ERK and cell migration. Dev Cell 2011; 20:751-63. [PMID: 21664574 DOI: 10.1016/j.devcel.2011.05.007] [Citation(s) in RCA: 108] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 02/08/2011] [Accepted: 05/09/2011] [Indexed: 12/21/2022]
Abstract
Cells are dependent on correct sorting of activated receptor tyrosine kinases (RTKs) for the outcome of growth factor signaling. Upon activation, RTKs are coupled through the endocytic machinery for degradation or recycled to the cell surface. However, the molecular mechanisms governing RTK recycling are poorly understood. Here, we show that Golgi-localized gamma ear-containing Arf-binding protein 3 (GGA3) interacts selectively with the Met/hepatocyte growth factor RTK when stimulated, to sort it for recycling in association with "gyrating" clathrin. GGA3 loss abrogates Met recycling from a Rab4 endosomal subdomain, resulting in pronounced trafficking of Met toward degradation. Decreased Met recycling attenuates ERK activation and cell migration. Met recycling, sustained ERK activation, and migration require interaction of GGA3 with Arf6 and an unexpected association with the Crk adaptor. The data show that GGA3 defines an active recycling pathway and support a broader role for GGA3-mediated cargo selection in targeting receptors destined for recycling.
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Noise-induced modulation of the relaxation kinetics around a non-equilibrium steady state of non-linear chemical reaction networks. PLoS One 2011; 6:e16045. [PMID: 21297975 PMCID: PMC3030564 DOI: 10.1371/journal.pone.0016045] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2010] [Accepted: 12/02/2010] [Indexed: 12/11/2022] Open
Abstract
Stochastic effects from correlated noise non-trivially modulate the kinetics of non-linear chemical reaction networks. This is especially important in systems where reactions are confined to small volumes and reactants are delivered in bursts. We characterise how the two noise sources confinement and burst modulate the relaxation kinetics of a non-linear reaction network around a non-equilibrium steady state. We find that the lifetimes of species change with burst input and confinement. Confinement increases the lifetimes of all species that are involved in any non-linear reaction as a reactant. Burst monotonically increases or decreases lifetimes. Competition between burst-induced and confinement-induced modulation may hence lead to a non-monotonic modulation. We quantify lifetime as the integral of the time autocorrelation function (ACF) of concentration fluctuations around a non-equilibrium steady state of the reaction network. Furthermore, we look at the first and second derivatives of the ACF, each of which is affected in opposite ways by burst and confinement. This allows discriminating between these two noise sources. We analytically derive the ACF from the linear Fokker–Planck approximation of the chemical master equation in order to establish a baseline for the burst-induced modulation at low confinement. Effects of higher confinement are then studied using a partial-propensity stochastic simulation algorithm. The results presented here may help understand the mechanisms that deviate stochastic kinetics from its deterministic counterpart. In addition, they may be instrumental when using fluorescence-lifetime imaging microscopy (FLIM) or fluorescence-correlation spectroscopy (FCS) to measure confinement and burst in systems with known reaction rates, or, alternatively, to correct for the effects of confinement and burst when experimentally measuring reaction rates.
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Naughtin MJ, Sheffield DA, Rahman P, Hughes WE, Gurung R, Stow JL, Nandurkar HH, Dyson JM, Mitchell CA. The myotubularin phosphatase MTMR4 regulates sorting from early endosomes. J Cell Sci 2010; 123:3071-83. [PMID: 20736309 DOI: 10.1242/jcs.060103] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Phosphatidylinositol 3-phosphate [PtdIns(3)P] regulates endocytic trafficking and the sorting of receptors through early endosomes, including the rapid recycling of transferrin (Tfn). However, the phosphoinositide phosphatase that selectively opposes this function is unknown. The myotubularins are a family of eight catalytically active and six inactive enzymes that hydrolyse PtdIns(3)P to form PtdIns. However, the role each myotubularin family member plays in regulating endosomal PtdIns(3)P and thereby endocytic trafficking is not well established. Here, we identify the myotubularin family member MTMR4, which localizes to early endosomes and also to Rab11- and Sec15-positive recycling endosomes. In cells with MTMR4 knockdown, or following expression of the catalytically inactive MTMR4, MTMR4(C407A), the number of PtdIns(3)P-decorated endosomes significantly increased. MTMR4 overexpression delayed the exit of Tfn from early endosomes and its recycling to the plasma membrane. By contrast, expression of MTMR4(C407A), which acts as a dominant-negative construct, significantly accelerated Tfn recycling. However, in MTMR4 knockdown cells Tfn recycling was unchanged, suggesting that other MTMs might also contribute to recycling. MTMR4 regulated the subcellular distribution of Rab11 and, in cells with RNAi-mediated knockdown of MTMR4, Rab11 was directed away from the pericentriolar recycling compartment. The subcellular distribution of VAMP3, a v-SNARE protein that resides in recycling endosomes and endosome-derived transport vesicles, was also regulated by MTMR4. Therefore, MTMR4 localizes at the interface of early and recycling endosomes to regulate trafficking through this pathway.
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Affiliation(s)
- Monica J Naughtin
- Department of Biochemistry and Molecular Biology, Monash University, Wellington Road, Clayton 3800, Australia
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Hirst J, Sahlender DA, Choma M, Sinka R, Harbour ME, Parkinson M, Robinson MS. Spatial and Functional Relationship of GGAs and AP-1 inDrosophilaand HeLa Cells. Traffic 2009; 10:1696-710. [DOI: 10.1111/j.1600-0854.2009.00983.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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