1
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Ng XY, Cao M. Dysfunction of synaptic endocytic trafficking in Parkinson's disease. Neural Regen Res 2024; 19:2649-2660. [PMID: 38595283 PMCID: PMC11168511 DOI: 10.4103/nrr.nrr-d-23-01624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 12/12/2023] [Accepted: 01/03/2024] [Indexed: 04/11/2024] Open
Abstract
Parkinson's disease is characterized by the selective degeneration of dopamine neurons in the nigrostriatal pathway and dopamine deficiency in the striatum. The precise reasons behind the specific degeneration of these dopamine neurons remain largely elusive. Genetic investigations have identified over 20 causative PARK genes and 90 genomic risk loci associated with both familial and sporadic Parkinson's disease. Notably, several of these genes are linked to the synaptic vesicle recycling process, particularly the clathrin-mediated endocytosis pathway. This suggests that impaired synaptic vesicle recycling might represent an early feature of Parkinson's disease, followed by axonal degeneration and the eventual loss of dopamine cell bodies in the midbrain via a "dying back" mechanism. Recently, several new animal and cellular models with Parkinson's disease-linked mutations affecting the endocytic pathway have been created and extensively characterized. These models faithfully recapitulate certain Parkinson's disease-like features at the animal, circuit, and cellular levels, and exhibit defects in synaptic membrane trafficking, further supporting the findings from human genetics and clinical studies. In this review, we will first summarize the cellular and molecular findings from the models of two Parkinson's disease-linked clathrin uncoating proteins: auxilin (DNAJC6/PARK19) and synaptojanin 1 (SYNJ1/PARK20). The mouse models carrying these two PARK gene mutations phenocopy each other with specific dopamine terminal pathology and display a potent synergistic effect. Subsequently, we will delve into the involvement of several clathrin-mediated endocytosis-related proteins (GAK, endophilin A1, SAC2/INPP5F, synaptotagmin-11), identified as Parkinson's disease risk factors through genome-wide association studies, in Parkinson's disease pathogenesis. We will also explore the direct or indirect roles of some common Parkinson's disease-linked proteins (alpha-synuclein (PARK1/4), Parkin (PARK2), and LRRK2 (PARK8)) in synaptic endocytic trafficking. Additionally, we will discuss the emerging novel functions of these endocytic proteins in downstream membrane traffic pathways, particularly autophagy. Given that synaptic dysfunction is considered as an early event in Parkinson's disease, a deeper understanding of the cellular mechanisms underlying synaptic vesicle endocytic trafficking may unveil novel targets for early diagnosis and the development of interventional therapies for Parkinson's disease. Future research should aim to elucidate why generalized synaptic endocytic dysfunction leads to the selective degeneration of nigrostriatal dopamine neurons in Parkinson's disease.
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Affiliation(s)
- Xin Yi Ng
- Programme in Neuroscience and Behavioural Disorders, Duke-NUS Medical School, Singapore, Singapore
| | - Mian Cao
- Programme in Neuroscience and Behavioural Disorders, Duke-NUS Medical School, Singapore, Singapore
- Department of Physiology, National University of Singapore, Singapore, Singapore
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2
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Capella P, Asensio J, Troncoso M, Sosa MA, Seltzer AM. Evidence on differential role for alpha 1 and alpha 2 subtypes of AP-2 adaptin in the Central Nervous System. Neurosci Lett 2023; 808:137282. [PMID: 37127089 DOI: 10.1016/j.neulet.2023.137282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 04/24/2023] [Accepted: 04/28/2023] [Indexed: 05/03/2023]
Abstract
Two subtypes of alpha (α)subunits , α1and α2, belonging to AP-2 complex have been described in the central nervous system (CNS). The specific role of each subtype is still unclear. In this study, we evaluated the expression and interaction with cell membranes of both subtypes in the postnatal developing cerebral cortex and cerebellum in two rat strains that display distinct developmental features. We observed that α2 displays higher variations than α1 during development, and at lesser extent in the rats with delayed rate of development. Additionally, by in vitro binding assays we evaluated the interaction of α subunits with bovine brain membranes. Both subtypes displayed clear differences in their performance, maximum binding of α1 was higher and α2 reached it faster than α1. In addition, both subtypes displayed different binding to membranes when bivalent cations or nucleotides were added. We conclude that both subtypes interact differently with membranes and that they may play different roles in clathrin-mediated endocytosis in the CNS.
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Affiliation(s)
- P Capella
- Laboratorio de Biología y Fisiología Celular "Dr. Francisco Bertini"- Instituto de Histología y Embriología - FCM, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - J Asensio
- Plataforma de Neurobiología- Instituto de Histología y Embriología (CONICET), Mendoza. Argentina
| | - M Troncoso
- Laboratorio de Biología y Fisiología Celular "Dr. Francisco Bertini"- Instituto de Histología y Embriología - FCM, Universidad Nacional de Cuyo, Mendoza, Argentina; Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - M A Sosa
- Laboratorio de Biología y Fisiología Celular "Dr. Francisco Bertini"- Instituto de Histología y Embriología - FCM, Universidad Nacional de Cuyo, Mendoza, Argentina; Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - A M Seltzer
- Plataforma de Neurobiología- Instituto de Histología y Embriología (CONICET), Mendoza. Argentina.
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3
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Ng XY, Wu Y, Lin Y, Yaqoob SM, Greene LE, De Camilli P, Cao M. Mutations in Parkinsonism-linked endocytic proteins synaptojanin1 and auxilin have synergistic effects on dopaminergic axonal pathology. NPJ Parkinsons Dis 2023; 9:26. [PMID: 36792618 PMCID: PMC9932162 DOI: 10.1038/s41531-023-00465-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 01/20/2023] [Indexed: 02/17/2023] Open
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder characterized by defective dopaminergic (DAergic) input to the striatum. Mutations in two genes encoding synaptically enriched clathrin-uncoating factors, synaptojanin 1 (SJ1) and auxilin, have been implicated in atypical Parkinsonism. SJ1 knock-in (SJ1-KIRQ) mice carrying a disease-linked mutation display neurological manifestations reminiscent of Parkinsonism. Here we report that auxilin knockout (Aux-KO) mice display dystrophic changes of a subset of nigrostriatal DAergic terminals similar to those of SJ1-KIRQ mice. Furthermore, Aux-KO/SJ1-KIRQ double mutant mice have shorter lifespan and more severe synaptic defects than single mutant mice. These include increase in dystrophic striatal nerve terminals positive for DAergic markers and for the PD risk protein SV2C, as well as adaptive changes in striatal interneurons. The synergistic effect of the two mutations demonstrates a special lability of DAergic neurons to defects in clathrin uncoating, with implications for PD pathogenesis in at least some forms of this condition.
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Affiliation(s)
- Xin Yi Ng
- Programme in Neuroscience and Behavioural Disorders, Duke-NUS Medical School, Singapore, Singapore
| | - Yumei Wu
- Departments of Neuroscience and Cell Biology, Howard Hughes Medical Institute, Program in Cellular Neuroscience, Neurodegeneration and Repair, Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT, 06510, USA
- Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, USA
| | - Youneng Lin
- Programme in Neuroscience and Behavioural Disorders, Duke-NUS Medical School, Singapore, Singapore
| | - Sidra Mohamed Yaqoob
- Programme in Neuroscience and Behavioural Disorders, Duke-NUS Medical School, Singapore, Singapore
| | - Lois E Greene
- Laboratory of Cell Biology, NHLBI, National Institutes of Health, Bethesda, MD, USA
| | - Pietro De Camilli
- Departments of Neuroscience and Cell Biology, Howard Hughes Medical Institute, Program in Cellular Neuroscience, Neurodegeneration and Repair, Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT, 06510, USA
- Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, USA
| | - Mian Cao
- Programme in Neuroscience and Behavioural Disorders, Duke-NUS Medical School, Singapore, Singapore.
- Department of Physiology, National University of Singapore, Singapore, Singapore.
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4
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Schechter M, Sharon R. An Emerging Role for Phosphoinositides in the Pathophysiology of Parkinson’s Disease. JOURNAL OF PARKINSON'S DISEASE 2021; 11:1725-1750. [PMID: 34151859 PMCID: PMC8609718 DOI: 10.3233/jpd-212684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Recent data support an involvement of defects in homeostasis of phosphoinositides (PIPs) in the pathophysiology of Parkinson’s disease (PD). Genetic mutations have been identified in genes encoding for PIP-regulating and PIP-interacting proteins, that are associated with familial and sporadic PD. Many of these proteins are implicated in vesicular membrane trafficking, mechanisms that were recently highlighted for their close associations with PD. PIPs are phosphorylated forms of the membrane phospholipid, phosphatidylinositol. Their composition in the vesicle’s membrane of origin, as well as membrane of destination, controls vesicular membrane trafficking. We review the converging evidence that points to the involvement of PIPs in PD. The review describes PD- and PIP-associated proteins implicated in clathrin-mediated endocytosis and autophagy, and highlights the involvement of α-synuclein in these mechanisms.
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Affiliation(s)
- Meir Schechter
- Department of Biochemistry and Molecular Biology, IMRIC, The Hebrew University-Hadassah Medical School, Ein Kerem, Jerusalem, Israel
| | - Ronit Sharon
- Department of Biochemistry and Molecular Biology, IMRIC, The Hebrew University-Hadassah Medical School, Ein Kerem, Jerusalem, Israel
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5
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Binotti B, Jahn R, Pérez-Lara Á. An overview of the synaptic vesicle lipid composition. Arch Biochem Biophys 2021; 709:108966. [PMID: 34139199 DOI: 10.1016/j.abb.2021.108966] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 06/10/2021] [Accepted: 06/10/2021] [Indexed: 11/29/2022]
Abstract
Chemical neurotransmission is the major mechanism of neuronal communication. Neurotransmitters are released from secretory organelles, the synaptic vesicles (SVs) via exocytosis into the synaptic cleft. Fusion of SVs with the presynaptic plasma membrane is balanced by endocytosis, thus maintaining the presynaptic membrane at steady-state levels. The protein machineries responsible for exo- and endocytosis have been extensively investigated. In contrast, less is known about the role of lipids in synaptic transmission and how the lipid composition of SVs is affected by dynamic exo-endocytotic cycling. Here we summarize the current knowledge about the composition, organization, and function of SV membrane lipids. We also cover lipid biogenesis and maintenance during the synaptic vesicle cycle.
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Affiliation(s)
- Beyenech Binotti
- Department of Biochemistry, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Reinhard Jahn
- Department of Neurobiology, Max-Planck-Institute for Biophysical Chemistry, Am Faßberg 11, 37077, Göttingen, Germany.
| | - Ángel Pérez-Lara
- Department of Physical Chemistry, University of Granada, Campus Universitario de Cartuja, 18071, Granada, Spain.
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He K, Song E, Upadhyayula S, Dang S, Gaudin R, Skillern W, Bu K, Capraro BR, Rapoport I, Kusters I, Ma M, Kirchhausen T. Dynamics of Auxilin 1 and GAK in clathrin-mediated traffic. J Cell Biol 2020; 219:133624. [PMID: 31962345 PMCID: PMC7054993 DOI: 10.1083/jcb.201908142] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 10/28/2019] [Accepted: 12/15/2019] [Indexed: 01/08/2023] Open
Abstract
Clathrin-coated vesicles lose their clathrin lattice within seconds of pinching off, through the action of the Hsc70 “uncoating ATPase.” The J- and PTEN-like domain–containing proteins, auxilin 1 (Aux1) and auxilin 2 (GAK), recruit Hsc70. The PTEN-like domain has no phosphatase activity, but it can recognize phosphatidylinositol phosphate head groups. Aux1 and GAK appear on coated vesicles in successive transient bursts, immediately after dynamin-mediated membrane scission has released the vesicle from the plasma membrane. These bursts contain a very small number of auxilins, and even four to six molecules are sufficient to mediate uncoating. In contrast, we could not detect auxilins in abortive pits or at any time during coated pit assembly. We previously showed that clathrin-coated vesicles have a dynamic phosphoinositide landscape, and we have proposed that lipid head group recognition might determine the timing of Aux1 and GAK appearance. The differential recruitment of Aux1 and GAK correlates with temporal variations in phosphoinositide composition, consistent with a lipid-switch timing mechanism.
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Affiliation(s)
- Kangmin He
- Department of Cell Biology, Harvard Medical School, Boston, MA.,Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA.,Department of Pediatrics, Harvard Medical School, Boston, MA
| | - Eli Song
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA
| | - Srigokul Upadhyayula
- Department of Cell Biology, Harvard Medical School, Boston, MA.,Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA.,Department of Pediatrics, Harvard Medical School, Boston, MA
| | - Song Dang
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA
| | - Raphael Gaudin
- Department of Cell Biology, Harvard Medical School, Boston, MA.,Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA
| | - Wesley Skillern
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA
| | - Kevin Bu
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA
| | | | - Iris Rapoport
- Department of Cell Biology, Harvard Medical School, Boston, MA
| | - Ilja Kusters
- Department of Cell Biology, Harvard Medical School, Boston, MA.,Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA
| | - Minghe Ma
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA
| | - Tom Kirchhausen
- Department of Cell Biology, Harvard Medical School, Boston, MA.,Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA.,Department of Pediatrics, Harvard Medical School, Boston, MA
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7
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Redpath GMI, Betzler VM, Rossatti P, Rossy J. Membrane Heterogeneity Controls Cellular Endocytic Trafficking. Front Cell Dev Biol 2020; 8:757. [PMID: 32850860 PMCID: PMC7419583 DOI: 10.3389/fcell.2020.00757] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 07/20/2020] [Indexed: 12/21/2022] Open
Abstract
Endocytic trafficking relies on highly localized events in cell membranes. Endocytosis involves the gathering of protein (cargo/receptor) at distinct plasma membrane locations defined by specific lipid and protein compositions. Simultaneously, the molecular machinery that drives invagination and eventually scission of the endocytic vesicle assembles at the very same place on the inner leaflet of the membrane. It is membrane heterogeneity - the existence of specific lipid and protein domains in localized regions of membranes - that creates the distinct molecular identity required for an endocytic event to occur precisely when and where it is required rather than at some random location within the plasma membrane. Accumulating evidence leads us to believe that the trafficking fate of internalized proteins is sealed following endocytosis, as this distinct membrane identity is preserved through the endocytic pathway, upon fusion of endocytic vesicles with early and sorting endosomes. In fact, just like at the plasma membrane, multiple domains coexist at the surface of these endosomes, regulating local membrane tubulation, fission and sorting to recycling pathways or to the trans-Golgi network via late endosomes. From here, membrane heterogeneity ensures that fusion events between intracellular vesicles and larger compartments are spatially regulated to promote the transport of cargoes to their intracellular destination.
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Affiliation(s)
- Gregory M I Redpath
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand.,The ANZAC Research Institute, Concord Repatriation General Hospital, Concord, NSW, Australia
| | - Verena M Betzler
- Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland.,Biotechnology Institute Thurgau (BITg) at the University of Konstanz, Kreuzlingen, Switzerland
| | - Pascal Rossatti
- Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland.,Biotechnology Institute Thurgau (BITg) at the University of Konstanz, Kreuzlingen, Switzerland
| | - Jérémie Rossy
- Biotechnology Institute Thurgau (BITg) at the University of Konstanz, Kreuzlingen, Switzerland.,Department of Biology, University of Konstanz, Konstanz, Germany
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8
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Absence of Sac2/INPP5F enhances the phenotype of a Parkinson's disease mutation of synaptojanin 1. Proc Natl Acad Sci U S A 2020; 117:12428-12434. [PMID: 32424101 PMCID: PMC7275725 DOI: 10.1073/pnas.2004335117] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Extensive genetic studies have identified numerous genes whose mutations results on Parkinson’s disease (PD), including synaptojanin 1 (SJ1/Park20), a nerve terminal enriched protein that includes an inositol 4-phosphatase domain (Sac domain). In addition, many PD candidate genes have been identified by genome-wide association studies, but for most of these genes, the link to PD remains hypothetical. One such gene is Sac2/INPP5F, which, interestingly, also includes an inositol 4-phosphatase domain. While Sac2KO mice do not show obvious defects, we show a striking synthetic effect in mice of the KO of Sac2 and the Sac domain mutation of SJ1 found in PD patients. These findings support a synergistic role of SJ1 and Sac2 on a PI4P pool whose dysfunction results in PD. Numerous genes whose mutations cause, or increase the risk of, Parkinson’s disease (PD) have been identified. An inactivating mutation (R258Q) in the Sac inositol phosphatase domain of synaptojanin 1 (SJ1/PARK20), a phosphoinositide phosphatase implicated in synaptic vesicle recycling, results in PD. The gene encoding Sac2/INPP5F, another Sac domain-containing protein, is located within a PD risk locus identified by genome-wide association studies. Knock-In mice carrying the SJ1 patient mutation (SJ1RQKI) exhibit PD features, while Sac2 knockout mice (Sac2KO) do not have obvious neurologic defects. We report a “synthetic” effect of the SJ1 mutation and the KO of Sac2 in mice. Most mice with both mutations died perinatally. The occasional survivors had stunted growth, died within 3 wk, and showed abnormalities of striatal dopaminergic nerve terminals at an earlier stage than SJ1RQKI mice. The abnormal accumulation of endocytic factors observed at synapses of cultured SJ1RQKI neurons was more severe in double-mutant neurons. Our results suggest that SJ1 and Sac2 have partially overlapping functions and are consistent with a potential role of Sac2 as a PD risk gene.
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Abstract
The tumor suppressor phosphatase and tensin homolog on chromosome 10 (PTEN) is a tightly regulated enzyme responsible for dephosphorylating the progrowth lipid messenger molecule phosphatidylinositol 3,4,5-trisphosphate (PIP3) on the plasma membrane. The carboxy-terminal tail (CTT) of PTEN is key for regulation of the enzyme. When phosphorylated, the unstructured CTT interacts with the phosphatase-C2 superdomain to inactivate the enzyme by preventing membrane association. PTEN mutations associated with cancer also inactivate the enzyme. Alternate translation-initiation sites generate extended isoforms of PTEN, such as PTEN-L that has multiple roles in cells. The extended amino-terminal region bears a signal sequence and a polyarginine sequence to facilitate exit from and entry into cells, respectively, and a membrane-binding helix that activates the enzyme. This amino-terminal region also facilitates mitochondrial and nucleolar localization. This review explores PTEN structure and its impact on localization and regulation.
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10
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Watanabe S, Mamer LE, Raychaudhuri S, Luvsanjav D, Eisen J, Trimbuch T, Söhl-Kielczynski B, Fenske P, Milosevic I, Rosenmund C, Jorgensen EM. Synaptojanin and Endophilin Mediate Neck Formation during Ultrafast Endocytosis. Neuron 2019; 98:1184-1197.e6. [PMID: 29953872 DOI: 10.1016/j.neuron.2018.06.005] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 05/12/2018] [Accepted: 06/04/2018] [Indexed: 11/19/2022]
Abstract
Ultrafast endocytosis generates vesicles from the plasma membrane as quickly as 50 ms in hippocampal neurons following synaptic vesicle fusion. The molecular mechanism underlying the rapid maturation of these endocytic pits is not known. Here we demonstrate that synaptojanin-1, and its partner endophilin-A, function in ultrafast endocytosis. In the absence of synaptojanin or endophilin, the membrane is rapidly invaginated, but pits do not become constricted at the base. The 5-phosphatase activity of synaptojanin is involved in formation of the neck, but 4-phosphatase is not required. Nevertheless, these pits are eventually cleaved into vesicles; within a 30-s interval, synaptic endosomes form and are resolved by clathrin-mediated budding. Then synaptojanin and endophilin function at a second step to aid with the removal of clathrin coats from the regenerated vesicles. These data together suggest that synaptojanin and endophilin can mediate membrane remodeling on a millisecond timescale during ultrafast endocytosis.
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Affiliation(s)
- Shigeki Watanabe
- Department of Neurophysiology, NeuroCure Cluster of Excellence, Charité-Universitätsmedizin Berlin, Berlin, Germany; Department of Cell Biology, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA; Solomon H. Snyder Department of Neuroscience, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA.
| | - Lauren Elizabeth Mamer
- Department of Neurophysiology, NeuroCure Cluster of Excellence, Charité-Universitätsmedizin Berlin, Berlin, Germany; The Ohio State University College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Sumana Raychaudhuri
- Department of Cell Biology, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA
| | - Delgermaa Luvsanjav
- Department of Cell Biology, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA
| | - Julia Eisen
- Barnard College of Columbia University, New York, NY, USA
| | - Thorsten Trimbuch
- Department of Neurophysiology, NeuroCure Cluster of Excellence, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Berit Söhl-Kielczynski
- Department of Neurophysiology, NeuroCure Cluster of Excellence, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Pascal Fenske
- Department of Neurophysiology, NeuroCure Cluster of Excellence, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Ira Milosevic
- Synaptic Vesicle Dynamics, European Neuroscience Institute, University Medical Center Göttingen, 37077 Göttingen, Germany
| | - Christian Rosenmund
- Department of Neurophysiology, NeuroCure Cluster of Excellence, Charité-Universitätsmedizin Berlin, Berlin, Germany.
| | - Erik M Jorgensen
- Department of Neurophysiology, NeuroCure Cluster of Excellence, Charité-Universitätsmedizin Berlin, Berlin, Germany; Department of Biology and Howard Hughes Medical Institute, University of Utah, Salt Lake City, UT 84112-0840, USA.
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12
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Inoshita T, Cui C, Hattori N, Imai Y. Regulation of membrane dynamics by Parkinson's disease-associated genes. J Genet 2018; 97:715-725. [PMID: 30027905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Parkinson's disease (PD), the second most common neurodegenerative disease after Alzheimer's disease, develops sporadically, and its cause is unknown. However, 5-10% of PD cases are inherited as monogenic diseases, which provides a chance to understand the molecular mechanisms underlying neurodegeneration. Over 20 causative genes have already been identified and are being characterized. These PD-associated genes are broadly classified into two groups: genes involved in mitochondrial functions and genes related to membrane dynamics such as intracellular vesicle transport and the lysosomal pathway. In this review, we summarize the latest findings on the mechanism by which members of the latter group of PD-associated genes regulate membrane dynamics, and we discuss how mutations of these genes lead to dopaminergic neurodegeneration.
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Affiliation(s)
- Tsuyoshi Inoshita
- Department of Research for Parkinson's Disease, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan.
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13
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He K, Marsland R, Upadhyayula S, Song E, Dang S, Capraro BR, Wang W, Skillern W, Gaudin R, Ma M, Kirchhausen T. Dynamics of phosphoinositide conversion in clathrin-mediated endocytic traffic. Nature 2017; 552:410-414. [PMID: 29236694 PMCID: PMC6263037 DOI: 10.1038/nature25146] [Citation(s) in RCA: 99] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 11/13/2017] [Indexed: 12/22/2022]
Abstract
Vesicular carriers transport proteins and lipids from one organelle to another, recognizing specific identifiers for the donor and acceptor membranes. Two important identifiers are phosphoinositides and GTP-bound GTPases, which provide well-defined but mutable labels. Phosphatidylinositol and its phosphorylated derivatives are present on the cytosolic faces of most cellular membranes. Reversible phosphorylation of its headgroup produces seven distinct phosphoinositides. In endocytic traffic, phosphatidylinositol-4,5-biphosphate marks the plasma membrane, and phosphatidylinositol-3-phosphate and phosphatidylinositol-4-phosphate mark distinct endosomal compartments. It is unknown what sequence of changes in lipid content confers on the vesicles their distinct identity at each intermediate step. Here we describe 'coincidence-detecting' sensors that selectively report the phosphoinositide composition of clathrin-associated structures, and the use of these sensors to follow the dynamics of phosphoinositide conversion during endocytosis. The membrane of an assembling coated pit, in equilibrium with the surrounding plasma membrane, contains phosphatidylinositol-4,5-biphosphate and a smaller amount of phosphatidylinositol-4-phosphate. Closure of the vesicle interrupts free exchange with the plasma membrane. A substantial burst of phosphatidylinositol-4-phosphate immediately after budding coincides with a burst of phosphatidylinositol-3-phosphate, distinct from any later encounter with the phosphatidylinositol-3-phosphate pool in early endosomes; phosphatidylinositol-3,4-biphosphate and the GTPase Rab5 then appear and remain as the uncoating vesicles mature into Rab5-positive endocytic intermediates. Our observations show that a cascade of molecular conversions, made possible by the separation of a vesicle from its parent membrane, can label membrane-traffic intermediates and determine their destinations.
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Affiliation(s)
- Kangmin He
- Department of Cell Biology, Harvard Medical School, 200 Longwood Ave, Boston, Massachusetts 02115, USA
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, 200 Longwood Ave, Boston, Massachusetts 02115, USA
- Department of Pediatrics, Harvard Medical School, 200 Longwood Ave, Boston, Massachusetts 02115, USA
| | - Robert Marsland
- Physics of Living Systems Group, Massachusetts Institute of Technology, 400 Technology Square, Cambridge, Massachusetts 02139, USA
| | - Srigokul Upadhyayula
- Department of Cell Biology, Harvard Medical School, 200 Longwood Ave, Boston, Massachusetts 02115, USA
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, 200 Longwood Ave, Boston, Massachusetts 02115, USA
- Department of Pediatrics, Harvard Medical School, 200 Longwood Ave, Boston, Massachusetts 02115, USA
| | - Eli Song
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, 200 Longwood Ave, Boston, Massachusetts 02115, USA
| | - Song Dang
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, 200 Longwood Ave, Boston, Massachusetts 02115, USA
| | - Benjamin R Capraro
- Department of Cell Biology, Harvard Medical School, 200 Longwood Ave, Boston, Massachusetts 02115, USA
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, 200 Longwood Ave, Boston, Massachusetts 02115, USA
| | - Weiming Wang
- Department of Cell Biology, Harvard Medical School, 200 Longwood Ave, Boston, Massachusetts 02115, USA
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, 200 Longwood Ave, Boston, Massachusetts 02115, USA
| | - Wesley Skillern
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, 200 Longwood Ave, Boston, Massachusetts 02115, USA
| | - Raphael Gaudin
- Department of Cell Biology, Harvard Medical School, 200 Longwood Ave, Boston, Massachusetts 02115, USA
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, 200 Longwood Ave, Boston, Massachusetts 02115, USA
| | - Minghe Ma
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, 200 Longwood Ave, Boston, Massachusetts 02115, USA
| | - Tom Kirchhausen
- Department of Cell Biology, Harvard Medical School, 200 Longwood Ave, Boston, Massachusetts 02115, USA
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, 200 Longwood Ave, Boston, Massachusetts 02115, USA
- Department of Pediatrics, Harvard Medical School, 200 Longwood Ave, Boston, Massachusetts 02115, USA
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14
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Parkinson Sac Domain Mutation in Synaptojanin 1 Impairs Clathrin Uncoating at Synapses and Triggers Dystrophic Changes in Dopaminergic Axons. Neuron 2017; 93:882-896.e5. [PMID: 28231468 DOI: 10.1016/j.neuron.2017.01.019] [Citation(s) in RCA: 119] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 11/22/2016] [Accepted: 01/20/2017] [Indexed: 01/10/2023]
Abstract
Synaptojanin 1 (SJ1) is a major presynaptic phosphatase that couples synaptic vesicle endocytosis to the dephosphorylation of PI(4,5)P2, a reaction needed for the shedding of endocytic factors from their membranes. While the role of SJ1's 5-phosphatase module in this process is well recognized, the contribution of its Sac phosphatase domain, whose preferred substrate is PI4P, remains unclear. Recently a homozygous mutation in its Sac domain was identified in early-onset parkinsonism patients. We show that mice carrying this mutation developed neurological manifestations similar to those of human patients. Synapses of these mice displayed endocytic defects and a striking accumulation of clathrin-coated intermediates, strongly implicating Sac domain's activity in endocytic protein dynamics. Mutant brains had elevated auxilin (PARK19) and parkin (PARK2) levels. Moreover, dystrophic axonal terminal changes were selectively observed in dopaminergic axons in the dorsal striatum. These results strengthen evidence for a link between synaptic endocytic dysfunction and Parkinson's disease.
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15
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Gorenberg EL, Chandra SS. The Role of Co-chaperones in Synaptic Proteostasis and Neurodegenerative Disease. Front Neurosci 2017; 11:248. [PMID: 28579939 PMCID: PMC5437171 DOI: 10.3389/fnins.2017.00248] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 04/18/2017] [Indexed: 12/14/2022] Open
Abstract
Synapses must be preserved throughout an organism's lifespan to allow for normal brain function and behavior. Synapse maintenance is challenging given the long distances between the termini and the cell body, reliance on axonal transport for delivery of newly synthesized presynaptic proteins, and high rates of synaptic vesicle exo- and endocytosis. Hence, synapses rely on efficient proteostasis mechanisms to preserve their structure and function. To this end, the synaptic compartment has specific chaperones to support its functions. Without proper synaptic chaperone activity, local proteostasis imbalances lead to neurotransmission deficits, dismantling of synapses, and neurodegeneration. In this review, we address the roles of four synaptic chaperones in the maintenance of the nerve terminal, as well as their genetic links to neurodegenerative disease. Three of these are Hsp40 co-chaperones (DNAJs): Cysteine String Protein alpha (CSPα; DNAJC5), auxilin (DNAJC6), and Receptor-Mediated Endocytosis 8 (RME-8; DNAJC13). These co-chaperones contain a conserved J domain through which they form a complex with heat shock cognate 70 (Hsc70), enhancing the chaperone's ATPase activity. CSPα is a synaptic vesicle protein known to chaperone the t-SNARE SNAP-25 and the endocytic GTPase dynamin-1, thereby regulating synaptic vesicle exocytosis and endocytosis. Auxilin binds assembled clathrin cages, and through its interactions with Hsc70 leads to the uncoating of clathrin-coated vesicles, a process necessary for the regeneration of synaptic vesicles. RME-8 is a co-chaperone on endosomes and may have a role in clathrin-coated vesicle endocytosis on this organelle. These three co-chaperones maintain client function by preserving folding and assembly to prevent client aggregation, but they do not break down aggregates that have already formed. The fourth synaptic chaperone we will discuss is Heat shock protein 110 (Hsp110), which interacts with Hsc70, DNAJAs, and DNAJBs to constitute a disaggregase. Hsp110-related disaggregase activity is present at the synapse and is known to protect against aggregation of proteins such as α-synuclein. Congruent with their importance in the nervous system, mutations of these co-chaperones lead to familial neurodegenerative disease. CSPα mutations cause adult neuronal ceroid lipofuscinosis, while auxilin mutations result in early-onset Parkinson's disease, demonstrating their significance in preservation of the nervous system.
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Affiliation(s)
- Erica L Gorenberg
- Interdepartmental Neuroscience Program, Yale UniversityNew Haven, CT, United States
| | - Sreeganga S Chandra
- Department of Neurology, Yale UniversityNew Haven, CT, United States.,Department of Neuroscience, Yale UniversityNew Haven, CT, United States
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16
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Naguib A. Following the trail of lipids: Signals initiated by PI3K function at multiple cellular membranes. Sci Signal 2016; 9:re4. [DOI: 10.1126/scisignal.aad7885] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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17
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Meekins DA, Vander Kooi CW, Gentry MS. Structural mechanisms of plant glucan phosphatases in starch metabolism. FEBS J 2016; 283:2427-47. [PMID: 26934589 DOI: 10.1111/febs.13703] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2015] [Revised: 01/31/2016] [Accepted: 02/29/2016] [Indexed: 01/12/2023]
Abstract
Glucan phosphatases are a recently discovered class of enzymes that dephosphorylate starch and glycogen, thereby regulating energy metabolism. Plant genomes encode two glucan phosphatases, called Starch EXcess4 (SEX4) and Like Sex Four2 (LSF2), that regulate starch metabolism by selectively dephosphorylating glucose moieties within starch glucan chains. Recently, the structures of both SEX4 and LSF2 were determined, with and without phosphoglucan products bound, revealing the mechanism for their unique activities. This review explores the structural and enzymatic features of the plant glucan phosphatases, and outlines how they are uniquely adapted to perform their cellular functions. We outline the physical mechanisms used by SEX4 and LSF2 to interact with starch glucans: SEX4 binds glucan chains via a continuous glucan-binding platform comprising its dual-specificity phosphatase domain and carbohydrate-binding module, while LSF2 utilizes surface binding sites. SEX4 and LSF2 both contain a unique network of aromatic residues in their catalytic dual-specificity phosphatase domains that serve as glucan engagement platforms and are unique to the glucan phosphatases. We also discuss the phosphoglucan substrate specificities inherent to SEX4 and LSF2, and outline structural features within the active site that govern glucan orientation. This review defines the structural mechanism of the plant glucan phosphatases with respect to phosphatases, starch metabolism and protein-glucan interaction, thereby providing a framework for their application in both agricultural and industrial settings.
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Affiliation(s)
- David A Meekins
- Department of Molecular and Cellular Biochemistry and Center for Structural Biology, University of Kentucky, Lexington, KY, USA.,Division of Biology, Kansas State University, Manhattan, KS, USA
| | - Craig W Vander Kooi
- Department of Molecular and Cellular Biochemistry and Center for Structural Biology, University of Kentucky, Lexington, KY, USA
| | - Matthew S Gentry
- Department of Molecular and Cellular Biochemistry and Center for Structural Biology, University of Kentucky, Lexington, KY, USA
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18
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Alonso A, Pulido R. The extended human PTPome: a growing tyrosine phosphatase family. FEBS J 2015; 283:1404-29. [PMID: 26573778 DOI: 10.1111/febs.13600] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 10/02/2015] [Accepted: 11/13/2015] [Indexed: 12/13/2022]
Abstract
Tyr phosphatases are, by definition, enzymes that dephosphorylate phospho-Tyr (pTyr) from proteins. This activity is found in several structurally diverse protein families, including the protein Tyr phosphatase (PTP), arsenate reductase, rhodanese, haloacid dehalogenase (HAD) and His phosphatase (HP) families. Most of these families include members with substrate specificity for non-pTyr substrates, such as phospho-Ser/phospho-Thr, phosphoinositides, phosphorylated carbohydrates, mRNAs, or inorganic moieties. A Cys is essential for catalysis in PTPs, rhodanese and arsenate reductase enzymes, whereas this work is performed by an Asp in HAD phosphatases and by a His in HPs, via a catalytic mechanism shared by all of the different families. The category that contains most Tyr phosphatases is the PTP family, which, although it received its name from this activity, includes Ser, Thr, inositide, carbohydrate and RNA phosphatases, as well as some inactive pseudophosphatase proteins. Here, we propose an extended collection of human Tyr phosphatases, which we call the extended human PTPome. The addition of new members (SACs, paladin, INPP4s, TMEM55s, SSU72, and acid phosphatases) to the currently categorized PTP group of enzymes means that the extended human PTPome contains up to 125 proteins, of which ~ 40 are selective for pTyr. We set criteria to ascribe proteins to the extended PTPome, and summarize the more important features of the new PTPome members in the context of their phosphatase activity and their relationship with human disease.
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Affiliation(s)
- Andrés Alonso
- Instituto de Biología y Genética Molecular (IBGM), CSIC-Universidad de Valladolid, Valladolid, Spain
| | - Rafael Pulido
- Biocruces Health Research Institute, Barakaldo, Spain.,IKERBASQUE, Basque Foundation for Science, Bilbao, Spain
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19
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Robinson MS. Forty Years of Clathrin-coated Vesicles. Traffic 2015; 16:1210-38. [PMID: 26403691 DOI: 10.1111/tra.12335] [Citation(s) in RCA: 230] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Revised: 09/16/2015] [Accepted: 09/16/2015] [Indexed: 12/11/2022]
Abstract
The purification of coated vesicles and the discovery of clathrin by Barbara Pearse in 1975 was a landmark in cell biology. Over the past 40 years, work from many labs has uncovered the molecular details of clathrin and its associated proteins, including how they assemble into a coated vesicle and how they select cargo. Unexpected connections have been found with signalling, development, neuronal transmission, infection, immunity and genetic disorders. But there are still a number of unanswered questions, including how clathrin-mediated trafficking is regulated and how the machinery evolved.
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Affiliation(s)
- Margaret S Robinson
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
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20
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Park BC, Yim YI, Zhao X, Olszewski MB, Eisenberg E, Greene LE. The clathrin-binding and J-domains of GAK support the uncoating and chaperoning of clathrin by Hsc70 in the brain. J Cell Sci 2015; 128:3811-21. [PMID: 26345367 DOI: 10.1242/jcs.171058] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 08/27/2015] [Indexed: 12/19/2022] Open
Abstract
Cyclin-G-associated kinase (GAK), the ubiquitously expressed J-domain protein, is essential for the chaperoning and uncoating of clathrin that is mediated by Hsc70 (also known as HSPA8). Adjacent to the C-terminal J-domain that binds to Hsc70, GAK has a clathrin-binding domain that is linked to an N-terminal kinase domain through a PTEN-like domain. Knocking out GAK in fibroblasts caused inhibition of clathrin-dependent trafficking, which was rescued by expressing a 62-kDa fragment of GAK, comprising just the clathrin-binding and J-domains. Expressing this fragment as a transgene in mice rescued the lethality and the histological defects caused by knocking out GAK in the liver or in the brain. Furthermore, when both GAK and auxilin (also known as DNAJC6), the neuronal-specific homolog of GAK, were knocked out in the brain, mice expressing the 62-kDa GAK fragment were viable, lived a normal life-span and had no major behavior abnormalities. However, these mice were about half the size of wild-type mice. Therefore, the PTEN-like domains of GAK and auxilin are not essential for Hsc70-dependent chaperoning and uncoating of clathrin, but depending on the tissue, these domains appear to increase the efficiency of these co-chaperones.
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Affiliation(s)
- Bum-Chan Park
- Laboratory of Cell Biology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yang-In Yim
- Laboratory of Cell Biology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Xiaohong Zhao
- Laboratory of Cell Biology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Maciej B Olszewski
- Laboratory of Cell Biology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Evan Eisenberg
- Laboratory of Cell Biology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Lois E Greene
- Laboratory of Cell Biology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
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21
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Naguib A, Bencze G, Cho H, Zheng W, Tocilj A, Elkayam E, Faehnle CR, Jaber N, Pratt CP, Chen M, Zong WX, Marks MS, Joshua-Tor L, Pappin DJ, Trotman LC. PTEN functions by recruitment to cytoplasmic vesicles. Mol Cell 2015; 58:255-68. [PMID: 25866245 DOI: 10.1016/j.molcel.2015.03.011] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 01/18/2015] [Accepted: 03/05/2015] [Indexed: 12/21/2022]
Abstract
PTEN is proposed to function at the plasma membrane, where receptor tyrosine kinases are activated. However, the majority of PTEN is located throughout the cytoplasm. Here, we show that cytoplasmic PTEN is distributed along microtubules, tethered to vesicles via phosphatidylinositol 3-phosphate (PI(3)P), the signature lipid of endosomes. We demonstrate that the non-catalytic C2 domain of PTEN specifically binds PI(3)P through the CBR3 loop. Mutations render this loop incapable of PI(3)P binding and abrogate PTEN-mediated inhibition of PI 3-kinase/AKT signaling. This loss of function is rescued by fusion of the loop mutant PTEN to FYVE, the canonical PI(3)P binding domain, demonstrating the functional importance of targeting PTEN to endosomal membranes. Beyond revealing an upstream activation mechanism of PTEN, our data introduce the concept of PI 3-kinase signal activation on the vast plasma membrane that is contrasted by PTEN-mediated signal termination on the small, discrete surfaces of internalized vesicles.
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Affiliation(s)
- Adam Naguib
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Gyula Bencze
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Hyejin Cho
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Wu Zheng
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Ante Tocilj
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA; W. M. Keck Structural Biology Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Elad Elkayam
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA; W. M. Keck Structural Biology Laboratory, Cold Spring Harbor, NY 11724, USA; Howard Hughes Medical Institute, Cold Spring Harbor, NY 11724, USA
| | - Christopher R Faehnle
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA; W. M. Keck Structural Biology Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Nadia Jaber
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY 11794, USA
| | | | - Muhan Chen
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Wei-Xing Zong
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY 11794, USA
| | - Michael S Marks
- Department of Pathology & Laboratory of Medicine, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA; Department of Pathology & Laboratory of Medicine and Physiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Leemor Joshua-Tor
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA; W. M. Keck Structural Biology Laboratory, Cold Spring Harbor, NY 11724, USA; Howard Hughes Medical Institute, Cold Spring Harbor, NY 11724, USA
| | - Darryl J Pappin
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Lloyd C Trotman
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA.
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22
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Böcking T, Aguet F, Rapoport I, Banzhaf M, Yu A, Zeeh JC, Kirchhausen T. Key interactions for clathrin coat stability. Structure 2014; 22:819-29. [PMID: 24815030 DOI: 10.1016/j.str.2014.04.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 03/31/2014] [Accepted: 04/02/2014] [Indexed: 11/29/2022]
Abstract
Clathrin-coated vesicles are major carriers of vesicular traffic in eukaryotic cells. This endocytic pathway relies on cycles of clathrin coat assembly and Hsc70-mediated disassembly. Here we identify histidine residues as major determinants of lattice assembly and stability. They are located at the invariant interface between the proximal and distal segments of clathrin heavy chains, in triskelions centered on two adjacent vertices of the coated-vesicle lattice. Mutation of these histidine residues to glutamine alters the pH dependence of coat stability. We then describe single-particle fluorescence imaging experiments in which we follow the effect of these histidine mutations on susceptibility to Hsc70-dependent uncoating. Coats destabilized by these mutations require fewer Hsc70 molecules to initiate disassembly, as predicted by a model in which Hsc70 traps conformational distortions during the auxilin- and Hsc70:ATP-mediated uncoating reaction.
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Affiliation(s)
- Till Böcking
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA; Centre for Vascular Research, University of New South Wales, Sydney NSW 2052 Australia.
| | - François Aguet
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Iris Rapoport
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine at Boston Children's Hospital, Boston, MA 02115, USA
| | - Manuel Banzhaf
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine at Boston Children's Hospital, Boston, MA 02115, USA
| | - Anan Yu
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine at Boston Children's Hospital, Boston, MA 02115, USA
| | - Jean Christophe Zeeh
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine at Boston Children's Hospital, Boston, MA 02115, USA
| | - Tom Kirchhausen
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine at Boston Children's Hospital, Boston, MA 02115, USA.
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23
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Kirchhausen T, Owen D, Harrison SC. Molecular structure, function, and dynamics of clathrin-mediated membrane traffic. Cold Spring Harb Perspect Biol 2014; 6:a016725. [PMID: 24789820 DOI: 10.1101/cshperspect.a016725] [Citation(s) in RCA: 303] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Clathrin is a molecular scaffold for vesicular uptake of cargo at the plasma membrane, where its assembly into cage-like lattices underlies the clathrin-coated pits of classical endocytosis. This review describes the structures of clathrin, major cargo adaptors, and other proteins that participate in forming a clathrin-coated pit, loading its contents, pinching off the membrane as a lattice-enclosed vesicle, and recycling the components. It integrates as much of the structural information as possible at the time of writing into a sketch of the principal steps in coated-pit and coated-vesicle formation.
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Affiliation(s)
- Tom Kirchhausen
- Department of Cell Biology, Harvard Medical School/PCMM, Boston, Massachusetts 02115
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24
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Kalli AC, Devaney I, Sansom MSP. Interactions of phosphatase and tensin homologue (PTEN) proteins with phosphatidylinositol phosphates: insights from molecular dynamics simulations of PTEN and voltage sensitive phosphatase. Biochemistry 2014; 53:1724-32. [PMID: 24588644 PMCID: PMC4167384 DOI: 10.1021/bi5000299] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
![]()
The
phosphatase and tensin homologue (PTEN) and the Ciona
intestinalis voltage sensitive phosphatase (Ci-VSP) are both
phosphatidylinositol phosphate (PIP) phosphatases that contain a C2
domain. PTEN is a tumor suppressor protein that acts as a phosphatase
on PIP3 in mammalian cell membranes. It contains two principal
domains:
a phosphatase domain (PD) and a C2 domain. Despite detailed structural
and functional characterization, less is known about its mechanism
of interaction with PIP-containing lipid bilayers. Ci-VSP consists
of an N-terminal transmembrane voltage sensor domain and a C-terminal
PTEN domain, which in turn contains a PD and a C2 domain. The nature
of the interaction of the PTEN domain of Ci-VSP with membranes has
not been well established. We have used multiscale molecular dynamics
simulations to define the interaction mechanisms
of PTEN and of the Ci-VSP PTEN domains with PIP-containing lipid bilayers.
Our results suggest a novel mechanism of association of the PTEN with
such bilayers, in which an initial electrostatics-driven encounter
of the protein and bilayer is followed by reorientation of the protein
to optimize its interactions with PIP molecules in the membrane. Although
a PIP3 molecule binds close to the active site of PTEN,
our simulations suggest a further conformational change of the protein
may be required for catalytically productive binding to occur. Ci-VSP
interacted with membranes in an orientation comparable to that of
PTEN but bound directly to PIP-containing membranes without a subsequent
reorientation step. Again, PIP3 bound close to the active
site of the Ci-VSP PD, but not in a catalytically productive manner.
Interactions of Ci-VSP with the bilayer induced clustering of PIP
molecules around the protein.
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Affiliation(s)
- Antreas C Kalli
- Department of Biochemistry, University of Oxford , South Parks Road, Oxford OX1 3QU, U.K
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25
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Kalli AC, Morgan G, Sansom MSP. Interactions of the auxilin-1 PTEN-like domain with model membranes result in nanoclustering of phosphatidyl inositol phosphates. Biophys J 2014; 105:137-45. [PMID: 23823232 DOI: 10.1016/j.bpj.2013.05.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Revised: 05/06/2013] [Accepted: 05/07/2013] [Indexed: 11/18/2022] Open
Abstract
Auxilin-1 is a neuron-specific membrane-binding protein involved in a late stage of clathrin-mediated endocytosis. It recruits Hsc70, thus initiating uncoating of the clathrin-coated vesicles. Interactions of auxilin-1 with the vesicle membrane are crucial for this function and are mediated via an N-terminal PTEN-like domain. We have used multiscale molecular dynamics simulations to probe the interactions of the auxilin-1 PTEN-like domain with lipid bilayers containing differing phospholipid composition, including bilayers containing phosphatidyl inositol phosphates. Our results suggest a novel, to our knowledge, model for the auxilin/membrane encounter and subsequent interactions. Negatively charged lipids (especially PIP2) enhance binding of auxilin to lipid bilayers and facilitate its correct orientation relative to the membrane. Mutations in three basic residues (R301E/R307E/K311E) of the C2 subdomain of the PTEN-like domain perturbed its interaction with the bilayer, changing its orientation. The interaction of membrane-bound auxilin-1 PTEN-like domain with negatively charged lipid headgroups results in nanoclustering of PIP2 molecules in the adjacent bilayer leaflet.
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Affiliation(s)
- Antreas C Kalli
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
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26
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Lumb CN, Sansom MSP. Defining the membrane-associated state of the PTEN tumor suppressor protein. Biophys J 2013; 104:613-21. [PMID: 23442912 DOI: 10.1016/j.bpj.2012.12.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Revised: 11/28/2012] [Accepted: 12/04/2012] [Indexed: 11/19/2022] Open
Abstract
Phosphatase and tensin-homolog deleted on chromosome 10 (PTEN) is a tumor-suppressor protein that regulates phosphatidylinositol 3-kinase (PI3-K) signaling by binding to the plasma membrane and hydrolyzing the 3' phosphate from phosphatidylinositol (3,4,5)-trisphosphate (PI(3,4,5)P3) to form phosphatidylinositol (4,5)-bisphosphate (PI(4,5)P2). Several loss-of-function mutations in PTEN that impair lipid phosphatase activity and membrane binding are oncogenic, leading to the development of a variety of cancers, but information about the membrane-associated state of PTEN remains sparse. We have modeled a membrane-associated state of the truncated PTEN structure bound to PI(3,4,5)P3 via multiscale molecular dynamics simulations. We show that the location of the membrane-binding surface agrees with experimental observations and is robust to changes in lipid composition. The level of membrane interaction is substantially reduced in the phosphatase domain for the triple mutant R161E/K163E/K164E, in line with experimental results. We observe clustering of anionic lipids around the C2 domain in preference to the phosphatase domain, suggesting that the C2 domain is involved in nonspecific interactions with negatively charged lipid headgroups. Finally, our simulations suggest that the oncogenicity of the R335L mutation may be due to a reduction in the interaction of the mutant PTEN with anionic lipids.
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Affiliation(s)
- Craig N Lumb
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
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27
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28
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Young A, Stoilova-McPhie S, Rothnie A, Vallis Y, Harvey-Smith P, Ranson N, Kent H, Brodsky FM, Pearse BMF, Roseman A, Smith CJ. Hsc70-induced changes in clathrin-auxilin cage structure suggest a role for clathrin light chains in cage disassembly. Traffic 2013; 14:987-96. [PMID: 23710728 PMCID: PMC3776051 DOI: 10.1111/tra.12085] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Revised: 05/21/2013] [Accepted: 05/25/2013] [Indexed: 01/28/2023]
Abstract
The molecular chaperone, Hsc70, together with its co-factor, auxilin, facilitates the ATP-dependent removal of clathrin during clathrin-mediated endocytosis in cells. We have used cryo-electron microscopy to determine the 3D structure of a complex of clathrin, auxilin401-910 and Hsc70 at pH 6 in the presence of ATP, frozen within 20 seconds of adding Hsc70 in order to visualize events that follow the binding of Hsc70 to clathrin and auxilin before clathrin disassembly. In this map, we observe density beneath the vertex of the cage that we attribute to bound Hsc70. This density emerges asymmetrically from the clathrin vertex, suggesting preferential binding by Hsc70 for one of the three possible sites at the vertex. Statistical comparison with a map of whole auxilin and clathrin previously published by us reveals the location of statistically significant differences which implicate involvement of clathrin light chains in structural rearrangements which occur after Hsc70 is recruited. Clathrin disassembly assays using light scattering suggest that loss of clathrin light chains reduces the efficiency with which auxilin facilitates this reaction. These data support a regulatory role for clathrin light chains in clathrin disassembly in addition to their established role in regulating clathrin assembly.
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Affiliation(s)
- Anna Young
- School of Life Sciences, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK
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29
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UVB suppresses PTEN expression by upregulating miR-141 in HaCaT cells. J Biomed Res 2013; 25:135-40. [PMID: 23554681 PMCID: PMC3596705 DOI: 10.1016/s1674-8301(11)60017-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Revised: 02/26/2011] [Accepted: 03/03/2011] [Indexed: 11/21/2022] Open
Abstract
MicroRNAs (miRNAs) are 21 to 24 nucleotide, non-coding RNA molecules that post-transcriptionally regulate the expression of target genes. Ultraviolet B (UVB) radiation has been shown to inhibit phosphatase and tensin homolog deleted on chromosome 10 (PTEN) expression in HaCaT cells through an unknown mechanism. In this study, we investigated whether miR-141 can regulate UVB exposure-mediated inhibition of PTEN expression. Real-time RT-PCR, annexin V/fluorescein isothiocyanate staining, Western blotting and anti-miRNA oligonucleotide transfection were employed in this study. We found that upregulation of miR-141 expression after UVB irradiation was inversely correlated with PTEN expression levels in HaCaT cells. Furthermore, miR-141 expression increased apoptosis, while anti-miR-141 partly restored PTEN expression and reversed the pro-apoptosis effect of UVB. UVB suppresses the expression of PTEN by upregulating miR-141 in HaCaT cells. Therefore, miR-141 is a potential gene therapy target for UVB-induced photodamage.
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Kaneko T, Joshi R, Feller SM, Li SS. Phosphotyrosine recognition domains: the typical, the atypical and the versatile. Cell Commun Signal 2012; 10:32. [PMID: 23134684 PMCID: PMC3507883 DOI: 10.1186/1478-811x-10-32] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Accepted: 10/09/2012] [Indexed: 12/21/2022] Open
Abstract
SH2 domains are long known prominent players in the field of phosphotyrosine recognition within signaling protein networks. However, over the years they have been joined by an increasing number of other protein domain families that can, at least with some of their members, also recognise pTyr residues in a sequence-specific context. This superfamily of pTyr recognition modules, which includes substantial fractions of the PTB domains, as well as much smaller, or even single member fractions like the HYB domain, the PKCδ and PKCθ C2 domains and RKIP, represents a fascinating, medically relevant and hence intensely studied part of the cellular signaling architecture of metazoans. Protein tyrosine phosphorylation clearly serves a plethora of functions and pTyr recognition domains are used in a similarly wide range of interaction modes, which encompass, for example, partner protein switching, tandem recognition functionalities and the interaction with catalytically active protein domains. If looked upon closely enough, virtually no pTyr recognition and regulation event is an exact mirror image of another one in the same cell. Thus, the more we learn about the biology and ultrastructural details of pTyr recognition domains, the more does it become apparent that nature cleverly combines and varies a few basic principles to generate a sheer endless number of sophisticated and highly effective recognition/regulation events that are, under normal conditions, elegantly orchestrated in time and space. This knowledge is also valuable when exploring pTyr reader domains as diagnostic tools, drug targets or therapeutic reagents to combat human diseases.
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Affiliation(s)
- Tomonori Kaneko
- Department of Biochemistry and the Siebens-Drake Medical Research Institute, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, N6A 5C1, Canada.
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Abstract
Neurons can sustain high rates of synaptic transmission without exhausting their supply of synaptic vesicles. This property relies on a highly efficient local endocytic recycling of synaptic vesicle membranes, which can be reused for hundreds, possibly thousands, of exo-endocytic cycles. Morphological, physiological, molecular, and genetic studies over the last four decades have provided insight into the membrane traffic reactions that govern this recycling and its regulation. These studies have shown that synaptic vesicle endocytosis capitalizes on fundamental and general endocytic mechanisms but also involves neuron-specific adaptations of such mechanisms. Thus, investigations of these processes have advanced not only the field of synaptic transmission but also, more generally, the field of endocytosis. This article summarizes current information on synaptic vesicle endocytosis with an emphasis on the underlying molecular mechanisms and with a special focus on clathrin-mediated endocytosis, the predominant pathway of synaptic vesicle protein internalization.
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Affiliation(s)
- Yasunori Saheki
- Department of Cell Biology, Howard Hughes Medical Institute and Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, Connecticut 06510, USA
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Jackson LP, Kümmel D, Reinisch KM, Owen DJ. Structures and mechanisms of vesicle coat components and multisubunit tethering complexes. Curr Opin Cell Biol 2012; 24:475-83. [PMID: 22728063 PMCID: PMC3425711 DOI: 10.1016/j.ceb.2012.05.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Accepted: 05/23/2012] [Indexed: 11/17/2022]
Abstract
Eukaryotic cells face a logistical challenge in ensuring prompt and precise delivery of vesicular cargo to specific organelles within the cell. Coat protein complexes select cargo and initiate vesicle formation, while multisubunit tethering complexes participate in the delivery of vesicles to target membranes. Understanding these macromolecular assemblies has greatly benefited from their structural characterization. Recent structural data highlight principles in coat recruitment and uncoating in both the endocytic and retrograde pathways, and studies on the architecture of tethering complexes provide a framework for how they might link vesicles to the respective acceptor compartments and the fusion machinery.
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Affiliation(s)
- Lauren P Jackson
- Cambridge Institute for Medical Research, Department of Clinical Biochemistry, University of Cambridge, Cambridge CB2 0XY, UK.
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Milosevic I, Giovedi S, Lou X, Raimondi A, Collesi C, Shen H, Paradise S, O'Toole E, Ferguson S, Cremona O, De Camilli P. Recruitment of endophilin to clathrin-coated pit necks is required for efficient vesicle uncoating after fission. Neuron 2012; 72:587-601. [PMID: 22099461 DOI: 10.1016/j.neuron.2011.08.029] [Citation(s) in RCA: 245] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/29/2011] [Indexed: 12/01/2022]
Abstract
Endophilin is a membrane-binding protein with curvature-generating and -sensing properties that participates in clathrin-dependent endocytosis of synaptic vesicle membranes. Endophilin also binds the GTPase dynamin and the phosphoinositide phosphatase synaptojanin and is thought to coordinate constriction of coated pits with membrane fission (via dynamin) and subsequent uncoating (via synaptojanin). We show that although synaptojanin is recruited by endophilin at bud necks before fission, the knockout of all three mouse endophilins results in the accumulation of clathrin-coated vesicles, but not of clathrin-coated pits, at synapses. The absence of endophilin impairs but does not abolish synaptic transmission and results in perinatal lethality, whereas partial endophilin absence causes severe neurological defects, including epilepsy and neurodegeneration. Our data support a model in which endophilin recruitment to coated pit necks, because of its curvature-sensing properties, primes vesicle buds for subsequent uncoating after membrane fission, without being critically required for the fission reaction itself.
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Affiliation(s)
- Ira Milosevic
- Department of Cell Biology, Howard Hughes Medical Institute, Program in Cellular Neuroscience, Neurodegeneration, and Repair, Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT 06519, USA
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Abstract
Synaptic transmission is amongst the most sophisticated and tightly controlled biological phenomena in higher eukaryotes. In the past few decades, tremendous progress has been made in our understanding of the molecular mechanisms underlying multiple facets of neurotransmission, both pre- and postsynaptically. Brought under the spotlight by pioneer studies in the areas of secretion and signal transduction, phosphoinositides and their metabolizing enzymes have been increasingly recognized as key protagonists in fundamental aspects of neurotransmission. Not surprisingly, dysregulation of phosphoinositide metabolism has also been implicated in synaptic malfunction associated with a variety of brain disorders. In the present chapter, we summarize current knowledge on the role of phosphoinositides at the neuronal synapse and highlight some of the outstanding questions in this research field.
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Affiliation(s)
- Samuel G Frere
- Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, 630 West 168th Street, P&S 12-420C, 10032, New York, USA
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Raimondi A, Ferguson SM, Lou X, Armbruster M, Paradise S, Giovedi S, Messa M, Kono N, Takasaki J, Cappello V, O'Toole E, Ryan TA, De Camilli P. Overlapping role of dynamin isoforms in synaptic vesicle endocytosis. Neuron 2011; 70:1100-14. [PMID: 21689597 DOI: 10.1016/j.neuron.2011.04.031] [Citation(s) in RCA: 149] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/11/2011] [Indexed: 10/18/2022]
Abstract
The existence of neuron-specific endocytic protein isoforms raises questions about their importance for specialized neuronal functions. Dynamin, a GTPase implicated in the fission reaction of endocytosis, is encoded by three genes, two of which, dynamin 1 and 3, are highly expressed in neurons. We show that dynamin 3, thought to play a predominantly postsynaptic role, has a major presynaptic function. Although lack of dynamin 3 does not produce an overt phenotype in mice, it worsens the dynamin 1 KO phenotype, leading to perinatal lethality and a more severe defect in activity-dependent synaptic vesicle endocytosis. Thus, dynamin 1 and 3, which together account for the overwhelming majority of brain dynamin, cooperate in supporting optimal rates of synaptic vesicle endocytosis. Persistence of synaptic transmission in their absence indicates that if dynamin plays essential functions in neurons, such functions can be achieved by the very low levels of dynamin 2.
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Affiliation(s)
- Andrea Raimondi
- Department of Cell Biology, HHMI, Program in Cellular Neuroscience, Neurodegeneration and Repair and Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT 06510, USA
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