1
|
Malhotra V. Tailored assemblies of COPII proteins in secretion. J Cell Biol 2024; 223:e202404013. [PMID: 38958655 PMCID: PMC11222725 DOI: 10.1083/jcb.202404013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/04/2024] Open
Abstract
Export of secretory cargoes from the endoplasmic reticulum (ER) requires COPII proteins, which were first identified for their ability to coat small vesicles that bud from the ER. Recent data indicate that COPII proteins can also organize into a collar at the necks of tubules, as well as phase-separate into liquid-like condensates. Thus, COPII assemblies seem to be tailored to accommodate variations in the size and quantities of cargo secreted.
Collapse
Affiliation(s)
- Vivek Malhotra
- Centre for Genomic Regulation, The Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra, Barcelona, Spain
- ICREA, Barcelona, Spain
| |
Collapse
|
2
|
Campelo F, Lillo JV, von Blume J. Protein condensates in the the secretory pathway: Unraveling biophysical interactions and function. Biophys J 2024; 123:1531-1541. [PMID: 38698644 PMCID: PMC11214006 DOI: 10.1016/j.bpj.2024.04.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 03/23/2024] [Accepted: 04/30/2024] [Indexed: 05/05/2024] Open
Abstract
The emergence of phase separation phenomena among macromolecules has identified biomolecular condensates as fundamental cellular organizers. These condensates concentrate specific components and accelerate biochemical reactions without relying on membrane boundaries. Although extensive studies have revealed a large variety of nuclear and cytosolic membraneless organelles, we are witnessing a surge in the exploration of protein condensates associated with the membranes of the secretory pathway, such as the endoplasmic reticulum and the Golgi apparatus. This review focuses on protein condensates in the secretory pathway and discusses their impact on the organization and functions of this cellular process. Moreover, we explore the modes of condensate-membrane association and the biophysical and cellular consequences of protein condensate interactions with secretory pathway membranes.
Collapse
Affiliation(s)
- Felix Campelo
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, Spain.
| | - Javier Vera Lillo
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, Spain
| | - Julia von Blume
- Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut.
| |
Collapse
|
3
|
Qiu H, Wu X, Ma X, Li S, Cai Q, Ganzella M, Ge L, Zhang H, Zhang M. Short-distance vesicle transport via phase separation. Cell 2024; 187:2175-2193.e21. [PMID: 38552623 DOI: 10.1016/j.cell.2024.03.003] [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: 01/31/2023] [Revised: 01/17/2024] [Accepted: 03/02/2024] [Indexed: 04/28/2024]
Abstract
In addition to long-distance molecular motor-mediated transport, cellular vesicles also need to be moved at short distances with defined directions to meet functional needs in subcellular compartments but with unknown mechanisms. Such short-distance vesicle transport does not involve molecular motors. Here, we demonstrate, using synaptic vesicle (SV) transport as a paradigm, that phase separation of synaptic proteins with vesicles can facilitate regulated, directional vesicle transport between different presynaptic bouton sub-compartments. Specifically, a large coiled-coil scaffold protein Piccolo, in response to Ca2+ and via its C2A domain-mediated Ca2+ sensing, can extract SVs from the synapsin-clustered reserve pool condensate and deposit the extracted SVs onto the surface of the active zone protein condensate. We further show that the Trk-fused gene, TFG, also participates in COPII vesicle trafficking from ER to the ER-Golgi intermediate compartment via phase separation. Thus, phase separation may play a general role in short-distance, directional vesicle transport in cells.
Collapse
Affiliation(s)
- Hua Qiu
- Division of Life Science, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Xiandeng Wu
- Division of Life Science, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Xiaoli Ma
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shulin Li
- State Key Laboratory of Membrane Biology, Beijing, China; Tsinghua-Peking Center for Life Sciences, Beijing 100084, China; School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Qixu Cai
- Division of Life Science, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China; State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, Department of Laboratory Medicine, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Marcelo Ganzella
- Department of Neurobiology, Max Planck Institute for Biophysical Chemistry, Göttingen 37077, Germany
| | - Liang Ge
- State Key Laboratory of Membrane Biology, Beijing, China; Tsinghua-Peking Center for Life Sciences, Beijing 100084, China; School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Hong Zhang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Mingjie Zhang
- Greater Bay Biomedical Innocenter, Shenzhen Bay Laboratory, Shenzhen 518036, China; School of Life Sciences, Southern University of Science and Technology, Shenzhen 518055, China.
| |
Collapse
|
4
|
Tetenborg S, Ariakia F, Martinez-Soler E, Shihabeddin E, Lazart IC, Miller AC, O’Brien J. Trafficking of Connexin36 (Cx36) in the early secretory pathway. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.25.586643. [PMID: 38585986 PMCID: PMC10996632 DOI: 10.1101/2024.03.25.586643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Gap junctions formed by the major neuronal connexin Cx36 function as electrical synapses in the nervous system and provide unique functions such as synchronizing activities or network oscillations. Although the physiological significance of electrical synapses for neuronal networks is well established, little is known about the pathways that regulate the transport of its main component: Cx36. Here we have used HEK293T cells as an expression system in combination with siRNA and BioID screens to study the transition of Cx36 from the ER to the cis Golgi. Our data indicate that the C-terminal tip of Cx36 is a key factor in this process, mediating binding interactions with two distinct components in the early secretory pathway: the COPII complex and the Golgi stacking protein Grasp55. The C-terminal amino acid valine serves as an ER export signal to recruit COPII cargo receptors Sec24A/B/C at ER exit sites, whereas the PDZ binding motif "SAYV" mediates an interaction with Grasp55. These two interactions have opposing effects in their respective compartments. While Sec24 subunits carry Cx36 out of the ER, Grasp55 stabilizes Cx36 in the Golgi as shown in over expression experiments. These early regulatory steps of Cx36 are expected to be essential for the formation, function, regulation and plasticity of electrical synapses in the developing and mature nervous system.
Collapse
Affiliation(s)
| | - Fatemeh Ariakia
- College of Optometry, University of Houston, Houston, TX, USA
- Contributed equally
| | | | - Eyad Shihabeddin
- College of Optometry, University of Houston, Houston, TX, USA
- MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA
| | - Ignacio Cebrian Lazart
- Instituto de Histología y Embriología de Mendoza (IHEM)-CONICET, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza 5500, Argentina
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain
| | - Adam C. Miller
- Institute of Neuroscience, Department of Biology, University of Oregon, Eugene, OR, USA
| | - John O’Brien
- College of Optometry, University of Houston, Houston, TX, USA
| |
Collapse
|
5
|
Hale AT, Boudreau H, Devulapalli R, Duy PQ, Atchley TJ, Dewan MC, Goolam M, Fieggen G, Spader HL, Smith AA, Blount JP, Johnston JM, Rocque BG, Rozzelle CJ, Chong Z, Strahle JM, Schiff SJ, Kahle KT. The genetic basis of hydrocephalus: genes, pathways, mechanisms, and global impact. Fluids Barriers CNS 2024; 21:24. [PMID: 38439105 PMCID: PMC10913327 DOI: 10.1186/s12987-024-00513-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Accepted: 01/25/2024] [Indexed: 03/06/2024] Open
Abstract
Hydrocephalus (HC) is a heterogenous disease characterized by alterations in cerebrospinal fluid (CSF) dynamics that may cause increased intracranial pressure. HC is a component of a wide array of genetic syndromes as well as a secondary consequence of brain injury (intraventricular hemorrhage (IVH), infection, etc.) that can present across the age spectrum, highlighting the phenotypic heterogeneity of the disease. Surgical treatments include ventricular shunting and endoscopic third ventriculostomy with or without choroid plexus cauterization, both of which are prone to failure, and no effective pharmacologic treatments for HC have been developed. Thus, there is an urgent need to understand the genetic architecture and molecular pathogenesis of HC. Without this knowledge, the development of preventive, diagnostic, and therapeutic measures is impeded. However, the genetics of HC is extraordinarily complex, based on studies of varying size, scope, and rigor. This review serves to provide a comprehensive overview of genes, pathways, mechanisms, and global impact of genetics contributing to all etiologies of HC in humans.
Collapse
Affiliation(s)
- Andrew T Hale
- Department of Neurosurgery, University of Alabama at Birmingham, FOT Suite 1060, 1720 2ndAve, Birmingham, AL, 35294, UK.
| | - Hunter Boudreau
- Department of Neurosurgery, University of Alabama at Birmingham, FOT Suite 1060, 1720 2ndAve, Birmingham, AL, 35294, UK
| | - Rishi Devulapalli
- Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, UK
| | - Phan Q Duy
- Department of Neurosurgery, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Travis J Atchley
- Department of Neurosurgery, University of Alabama at Birmingham, FOT Suite 1060, 1720 2ndAve, Birmingham, AL, 35294, UK
| | - Michael C Dewan
- Division of Pediatric Neurosurgery, Monroe Carell Jr. Children's Hospital, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Mubeen Goolam
- Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| | - Graham Fieggen
- Neuroscience Institute, University of Cape Town, Cape Town, South Africa
- Division of Pediatric Neurosurgery, Red Cross War Memorial Children's Hospital, University of Cape Town, Cape Town, South Africa
| | - Heather L Spader
- Department of Neurosurgery, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Anastasia A Smith
- Division of Pediatric Neurosurgery, Children's of Alabama, University of Alabama at Birmingham, Birmingham, AL, UK
| | - Jeffrey P Blount
- Division of Pediatric Neurosurgery, Children's of Alabama, University of Alabama at Birmingham, Birmingham, AL, UK
| | - James M Johnston
- Division of Pediatric Neurosurgery, Children's of Alabama, University of Alabama at Birmingham, Birmingham, AL, UK
| | - Brandon G Rocque
- Division of Pediatric Neurosurgery, Children's of Alabama, University of Alabama at Birmingham, Birmingham, AL, UK
| | - Curtis J Rozzelle
- Division of Pediatric Neurosurgery, Children's of Alabama, University of Alabama at Birmingham, Birmingham, AL, UK
| | - Zechen Chong
- Heflin Center for Genomics, University of Alabama at Birmingham, Birmingham, AL, UK
| | - Jennifer M Strahle
- Division of Pediatric Neurosurgery, St. Louis Children's Hospital, Washington University in St. Louis, St. Louis, MO, USA
| | - Steven J Schiff
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA
| | - Kristopher T Kahle
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| |
Collapse
|
6
|
Andhare D, Ragusa MJ. A new GUV-based assay to reconstitute membrane tethering in vitro demonstrates the vesicle tethering ability of the selective autophagy scaffold Atg11. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.19.572332. [PMID: 38187578 PMCID: PMC10769207 DOI: 10.1101/2023.12.19.572332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Membrane tethering is essential for the generation of organelle contact sites and to anchor incoming vesicles to their target membranes before vesicle fusion. During autophagy in yeast, tethering of 30 nm vesicles to cargo is one of the first steps in the generation of the isolation membrane that engulfs the cargo to be degraded. While membrane tethering is critical for cellular function, many of the current biochemical techniques to assay for membrane tethering rely on indirect readouts and are limited in their ability to monitor protein localization at sites of tethering. As such, we developed a fluorescence-microscopy-based GUV liposome tethering assay (GLT) to directly visualize membrane tethering and monitor protein localization at tethering sites simultaneously. We initially used GLT with engineered membrane tethers to demonstrate the ease of use, versatility and sensitivity of the assay. We also demonstrated that the selective autophagy scaffolding protein Atg11 can bind, and tether negatively charged membranes but is unable to bind GUVs mimicking the charge of the outer mitochondrial membrane. Atg11 instead requires the selective autophagy receptor Atg32 to be recruited to mitochondrial membranes. Lastly, we demonstrate that Atg11 bound to Atg32 on GUVs can tether negatively charged vesicles to GUVs. Collectively, our results reconstitute one of the first steps during the initiation of mitochondrial autophagy and highlight the versatility of GLT to study a range of membrane tethering events biochemically.
Collapse
Affiliation(s)
- Devika Andhare
- Department of Chemistry, Dartmouth College, Hanover, NH 03755, USA
| | - Michael J Ragusa
- Department of Chemistry, Dartmouth College, Hanover, NH 03755, USA
| |
Collapse
|
7
|
Gallo R, Rai AK, McIntyre ABR, Meyer K, Pelkmans L. DYRK3 enables secretory trafficking by maintaining the liquid-like state of ER exit sites. Dev Cell 2023; 58:1880-1897.e11. [PMID: 37643612 DOI: 10.1016/j.devcel.2023.08.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 02/16/2023] [Accepted: 08/01/2023] [Indexed: 08/31/2023]
Abstract
The dual-specificity kinase DYRK3 controls the formation and dissolution of multiple biomolecular condensates, regulating processes including stress recovery and mitotic progression. Here, we report that DYRK3 functionally interacts with proteins associated with endoplasmic reticulum (ER) exit sites (ERESs) and that inhibition of DYRK3 perturbs the organization of the ERES-Golgi interface and secretory trafficking. DYRK3-mediated regulation of ERES depends on the N-terminal intrinsically disordered region (IDR) of the peripheral membrane protein SEC16A, which co-phase separates with ERES components to form liquid-like condensates on the surface of the ER. By modulating the liquid-like properties of ERES, we show that their physical state is essential for functional cargo trafficking through the early secretory pathway. Our findings support a mechanism whereby phosphorylation by DYRK3 and its reversal by serine-threonine phosphatases regulate the material properties of ERES to create a favorable physicochemical environment for directional membrane traffic in eukaryotic cells.
Collapse
Affiliation(s)
- Raffaella Gallo
- Department of Molecular Life Sciences, University of Zurich, 8046 Zurich, Switzerland
| | - Arpan Kumar Rai
- Department of Molecular Life Sciences, University of Zurich, 8046 Zurich, Switzerland.
| | - Alexa B R McIntyre
- Department of Molecular Life Sciences, University of Zurich, 8046 Zurich, Switzerland
| | - Katrina Meyer
- Department of Molecular Life Sciences, University of Zurich, 8046 Zurich, Switzerland
| | - Lucas Pelkmans
- Department of Molecular Life Sciences, University of Zurich, 8046 Zurich, Switzerland.
| |
Collapse
|
8
|
Zeng Y, Liang Z, Liu Z, Li B, Cui Y, Gao C, Shen J, Wang X, Zhao Q, Zhuang X, Erdmann PS, Wong KB, Jiang L. Recent advances in plant endomembrane research and new microscopical techniques. THE NEW PHYTOLOGIST 2023; 240:41-60. [PMID: 37507353 DOI: 10.1111/nph.19134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 06/19/2023] [Indexed: 07/30/2023]
Abstract
The endomembrane system consists of various membrane-bound organelles including the endoplasmic reticulum (ER), Golgi apparatus, trans-Golgi network (TGN), endosomes, and the lysosome/vacuole. Membrane trafficking between distinct compartments is mainly achieved by vesicular transport. As the endomembrane compartments and the machineries regulating the membrane trafficking are largely conserved across all eukaryotes, our current knowledge on organelle biogenesis and endomembrane trafficking in plants has mainly been shaped by corresponding studies in mammals and yeast. However, unique perspectives have emerged from plant cell biology research through the characterization of plant-specific regulators as well as the development and application of the state-of-the-art microscopical techniques. In this review, we summarize our current knowledge on the plant endomembrane system, with a focus on several distinct pathways: ER-to-Golgi transport, protein sorting at the TGN, endosomal sorting on multivesicular bodies, vacuolar trafficking/vacuole biogenesis, and the autophagy pathway. We also give an update on advanced imaging techniques for the plant cell biology research.
Collapse
Affiliation(s)
- Yonglun Zeng
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Zizhen Liang
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Zhiqi Liu
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Baiying Li
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Yong Cui
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, 361102, China
| | - Caiji Gao
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Jinbo Shen
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, 311300, China
| | - Xiangfeng Wang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Qiong Zhao
- School of Life Sciences, East China Normal University, Shanghai, 200062, China
| | - Xiaohong Zhuang
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Philipp S Erdmann
- Human Technopole, Viale Rita Levi-Montalcini, 1, Milan, I-20157, Italy
| | - Kam-Bo Wong
- Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong (CUHK), Shatin, Hong Kong, China
| | - Liwen Jiang
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
- The CUHK Shenzhen Research Institute, Shenzhen, 518057, China
- Institute of Plant Molecular Biology and Agricultural Biotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| |
Collapse
|
9
|
Woo TT, Williams JM, Tsai B. How host ER membrane chaperones and morphogenic proteins support virus infection. J Cell Sci 2023; 136:jcs261121. [PMID: 37401530 PMCID: PMC10357032 DOI: 10.1242/jcs.261121] [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: 07/05/2023] Open
Abstract
The multi-functional endoplasmic reticulum (ER) is exploited by viruses to cause infection. Morphologically, this organelle is a highly interconnected membranous network consisting of sheets and tubules whose levels are dynamic, changing in response to cellular conditions. Functionally, the ER is responsible for protein synthesis, folding, secretion and degradation, as well as Ca2+ homeostasis and lipid biosynthesis, with each event catalyzed by defined ER factors. Strikingly, these ER host factors are hijacked by viruses to support different infection steps, including entry, translation, replication, assembly and egress. Although the full repertoire of these ER factors that are hijacked is unknown, recent studies have uncovered several ER membrane machineries that are exploited by viruses - ranging from polyomavirus to flavivirus and coronavirus - to facilitate different steps of their life cycle. These discoveries should provide better understanding of virus infection mechanisms, potentially leading to the development of more effective anti-viral therapies.
Collapse
Affiliation(s)
- Tai-Ting Woo
- Department of Cell and Developmental Biology, University of Michigan Medical School, 109 Zina Pitcher Place, BSRB 3043, Ann Arbor, MI 48109,USA
| | - Jeffrey M. Williams
- Department of Cell and Developmental Biology, University of Michigan Medical School, 109 Zina Pitcher Place, BSRB 3043, Ann Arbor, MI 48109,USA
| | - Billy Tsai
- Department of Cell and Developmental Biology, University of Michigan Medical School, 109 Zina Pitcher Place, BSRB 3043, Ann Arbor, MI 48109,USA
| |
Collapse
|
10
|
Aryal S, Bonanno K, Song B, Mani DR, Keshishian H, Carr SA, Sheng M, Dejanovic B. Deep proteomics identifies shared molecular pathway alterations in synapses of patients with schizophrenia and bipolar disorder and mouse model. Cell Rep 2023; 42:112497. [PMID: 37171958 DOI: 10.1016/j.celrep.2023.112497] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 03/10/2023] [Accepted: 04/26/2023] [Indexed: 05/14/2023] Open
Abstract
Synaptic dysfunction is implicated in the pathophysiology of schizophrenia (SCZ) and bipolar disorder (BP). We use quantitative mass spectrometry to carry out deep, unbiased proteomic profiling of synapses purified from the dorsolateral prefrontal cortex of 35 cases of SCZ, 35 cases of BP, and 35 controls. Compared with controls, SCZ and BP synapses show substantial and similar proteomic alterations. Network analyses reveal upregulation of proteins associated with autophagy and certain vesicle transport pathways and downregulation of proteins related to synaptic, mitochondrial, and ribosomal function in the synapses of individuals with SCZ or BP. Some of the same pathways are similarly dysregulated in the synaptic proteome of mutant mice deficient in Akap11, a recently discovered shared risk gene for SCZ and BP. Our work provides biological insights into molecular dysfunction at the synapse in SCZ and BP and serves as a resource for understanding the pathophysiology of these disorders.
Collapse
Affiliation(s)
- Sameer Aryal
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Kevin Bonanno
- The Proteomics Platform, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Bryan Song
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - D R Mani
- The Proteomics Platform, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Hasmik Keshishian
- The Proteomics Platform, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Steven A Carr
- The Proteomics Platform, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Morgan Sheng
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.
| | - Borislav Dejanovic
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
| |
Collapse
|
11
|
Shen Y, Gu HM, Qin S, Zhang DW. Surf4, cargo trafficking, lipid metabolism, and therapeutic implications. J Mol Cell Biol 2023; 14:6852946. [PMID: 36574593 PMCID: PMC9929512 DOI: 10.1093/jmcb/mjac063] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 07/30/2022] [Accepted: 09/06/2022] [Indexed: 12/03/2022] Open
Abstract
Surfeit 4 is a polytopic transmembrane protein that primarily resides in the endoplasmic reticulum (ER) membrane. It is ubiquitously expressed and functions as a cargo receptor, mediating cargo transport from the ER to the Golgi apparatus via the canonical coat protein complex II (COPII)-coated vesicles or specific vesicles. It also participates in ER-Golgi protein trafficking through a tubular network. Meanwhile, it facilitates retrograde transportation of cargos from the Golgi apparatus to the ER through COPI-coated vesicles. Surf4 can selectively mediate export of diverse cargos, such as PCSK9 very low-density lipoprotein (VLDL), progranulin, α1-antitrypsin, STING, proinsulin, and erythropoietin. It has been implicated in facilitating VLDL secretion, promoting cell proliferation and migration, and increasing replication of positive-strand RNA viruses. Therefore, Surf4 plays a crucial role in various physiological and pathophysiological processes and emerges as a promising therapeutic target. However, the molecular mechanisms by which Surf4 selectively sorts diverse cargos for ER-Golgi protein trafficking remain elusive. Here, we summarize the most recent advances in Surf4, focusing on its role in lipid metabolism.
Collapse
Affiliation(s)
- Yishi Shen
- Group on the Molecular and Cell Biology of Lipids and Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6R 2G3, Canada
| | - Hong-Mei Gu
- Group on the Molecular and Cell Biology of Lipids and Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6R 2G3, Canada
| | - Shucun Qin
- Institute of Atherosclerosis in Shandong First Medical University (Shandong Academy of Medical Sciences), Taian 271016, China
| | - Da-Wei Zhang
- Group on the Molecular and Cell Biology of Lipids and Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6R 2G3, Canada
| |
Collapse
|
12
|
Bao X, Wang Y, Qi Y, Lei C, Wang Y, Pan T, Yu M, Zhang Y, Wu H, Zhang P, Ji Y, Yang H, Jiang X, Jing R, Yan M, Zhang B, Gu C, Zhu J, Hao Y, Lei J, Zhang S, Chen X, Chen R, Sun Y, Zhu Y, Zhang X, Jiang L, Visser RGF, Ren Y, Wang Y, Wan J. A deleterious Sar1c variant in rice inhibits export of seed storage proteins from the endoplasmic reticulum. PLANT MOLECULAR BIOLOGY 2023; 111:291-307. [PMID: 36469200 DOI: 10.1007/s11103-022-01327-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 11/27/2022] [Indexed: 06/17/2023]
Abstract
We identified a dosage-dependent dominant negative form of Sar1c, which confirms the essential role of COPII system in mediating ER export of storage proteins in rice endosperm. Higher plants accumlate large amounts of seed storage proteins (SSPs). However, mechanisms underlying SSP trafficking are largely unknown, especially the ER-Golgi anterograde process. Here, we showed that a rice glutelin precursor accumulation13 (gpa13) mutant exhibited floury endosperm and overaccumulated glutelin precursors, which phenocopied the reported RNAi-Sar1abc line. Molecular cloning revealed that the gpa13 allele encodes a mutated Sar1c (mSar1c) with a deletion of two conserved amino acids Pro134 and Try135. Knockdown or knockout of Sar1c alone caused no obvious phenotype, while overexpression of mSar1c resulted in seedling lethality similar to the gpa13 mutant. Transient expression experiment in tobacco combined with subcellular fractionation experiment in gpa13 demonstrated that the expression of mSar1c affects the subcellular distribution of all Sar1 isoforms and Sec23c. In addition, mSar1c failed to interact with COPII component Sec23. Conversely, mSar1c competed with Sar1a/b/d to interact with guanine nucleotide exchange factor Sec12. Together, we identified a dosage-dependent dominant negative form of Sar1c, which confirms the essential role of COPII system in mediating ER export of storage proteins in rice endosperm.
Collapse
Affiliation(s)
- Xiuhao Bao
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Yongfei Wang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Yanzhou Qi
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China
- Plant Breeding, Wageningen University & Research, PO Box 386, 6700 AJ, Wageningen, the Netherlands
| | - Cailin Lei
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China
| | - Yunlong Wang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Tian Pan
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Mingzhou Yu
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Yu Zhang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Hongming Wu
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Pengcheng Zhang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Yi Ji
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Hang Yang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Xiaokang Jiang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Ruonan Jing
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Mengyuan Yan
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China
| | - Binglei Zhang
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China
| | - Chuanwei Gu
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Jianping Zhu
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Yuanyuan Hao
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Jie Lei
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Shuang Zhang
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China
| | - Xiaoli Chen
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Rongbo Chen
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Yinglun Sun
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Yun Zhu
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China
| | - Xin Zhang
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China
| | - Ling Jiang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Richard G F Visser
- Plant Breeding, Wageningen University & Research, PO Box 386, 6700 AJ, Wageningen, the Netherlands
| | - Yulong Ren
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China.
| | - Yihua Wang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China.
| | - Jianmin Wan
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China
| |
Collapse
|
13
|
Barrabi C, Zhang K, Liu M, Chen X. Pancreatic beta cell ER export in health and diabetes. Front Endocrinol (Lausanne) 2023; 14:1155779. [PMID: 37152949 PMCID: PMC10160654 DOI: 10.3389/fendo.2023.1155779] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 04/10/2023] [Indexed: 05/09/2023] Open
Abstract
In the secretory pathway of the pancreatic beta cell, proinsulin and other secretory granule proteins are first produced in the endoplasmic reticulum (ER). Beta cell ER homeostasis is vital for normal beta cell functions and is maintained by the delicate balance between protein synthesis, folding, export and degradation. Disruption of ER homeostasis leads to beta cell death and diabetes. Among the four components to maintain ER homeostasis, the role of ER export in insulin biogenesis or beta cell survival was not well-understood. COPII (coat protein complex II) dependent transport is a conserved mechanism for most cargo proteins to exit ER and transport to Golgi apparatus. Emerging evidence began to reveal a critical role of COPII-dependent ER export in beta cells. In this review, we will first discuss the basic components of the COPII transport machinery, the regulation of cargo entry and COPII coat assembly in mammalian cells, and the general concept of receptor-mediated cargo sorting in COPII vesicles. On the basis of these general discussions, the current knowledge and recent developments specific to the beta cell COPII dependent ER export are summarized under normal and diabetic conditions.
Collapse
Affiliation(s)
- Cesar Barrabi
- Department of Physiology, School of Medicine, Wayne State University, Detroit, MI, United States
| | - Kezhong Zhang
- Center for Molecular Medicine and Genetics, School of Medicine, Wayne State University, Detroit, MI, United States
| | - Ming Liu
- Department of Endocrinology and Metabolism, Tianjin Medical University General Hospital, Tianjin, China
| | - Xuequn Chen
- Department of Physiology, School of Medicine, Wayne State University, Detroit, MI, United States
- *Correspondence: Xuequn Chen,
| |
Collapse
|
14
|
van Leeuwen W, Nguyen DTM, Grond R, Veenendaal T, Rabouille C, Farías GG. Stress-induced phase separation of ERES components into Sec bodies precedes ER exit inhibition in mammalian cells. J Cell Sci 2022; 135:jcs260294. [PMID: 36325988 PMCID: PMC10112967 DOI: 10.1242/jcs.260294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 10/27/2022] [Indexed: 11/06/2022] Open
Abstract
Phase separation of components of ER exit sites (ERES) into membraneless compartments, the Sec bodies, occurs in Drosophila cells upon exposure to specific cellular stressors, namely, salt stress and amino acid starvation, and their formation is linked to the early secretory pathway inhibition. Here, we show Sec bodies also form in secretory mammalian cells upon the same stress. These reversible and membraneless structures are positive for ERES components, including both Sec16A and Sec16B isoforms and COPII subunits. We find that Sec16A, but not Sec16B, is a driver for Sec body formation, and that the coalescence of ERES components into Sec bodies occurs by fusion. Finally, we show that the stress-induced coalescence of ERES components into Sec bodies precedes ER exit inhibition, leading to their progressive depletion from ERES that become non-functional. Stress relief causes an immediate dissolution of Sec bodies and the concomitant restoration of ER exit. We propose that the dynamic conversion between ERES and Sec body assembly, driven by Sec16A, regulates protein exit from the ER during stress and upon stress relief in mammalian cells, thus providing a conserved pro-survival mechanism in response to stress.
Collapse
Affiliation(s)
- Wessel van Leeuwen
- Hubrecht Institute of the KNAW & UMC Utrecht, Utrecht 3584 CT, The Netherlands
| | - Dan T. M. Nguyen
- Cell Biology, Neurobiology and Biophysics. Department of Biology, Faculty of Science, Utrecht University, Utrecht 3584 CH, The Netherlands
| | - Rianne Grond
- Hubrecht Institute of the KNAW & UMC Utrecht, Utrecht 3584 CT, The Netherlands
| | - Tineke Veenendaal
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht 3584 CX, The Netherlands
| | - Catherine Rabouille
- Hubrecht Institute of the KNAW & UMC Utrecht, Utrecht 3584 CT, The Netherlands
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht 3584 CX, The Netherlands
- Department of Biomedical Sciences in Cells and Systems, UMC Groningen, Groningen 9713 AV, The Netherlands
| | - Ginny G. Farías
- Cell Biology, Neurobiology and Biophysics. Department of Biology, Faculty of Science, Utrecht University, Utrecht 3584 CH, The Netherlands
| |
Collapse
|
15
|
Ostwaldt F, Los B, Heyd F. In silico analysis of alternative splicing events implicated in intracellular trafficking during B-lymphocyte differentiation. Front Immunol 2022; 13:1030409. [DOI: 10.3389/fimmu.2022.1030409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Accepted: 10/20/2022] [Indexed: 11/11/2022] Open
Abstract
There are multiple regulatory layers that control intracellular trafficking and protein secretion, ranging from transcriptional to posttranslational mechanisms. Finely regulated trafficking and secretion is especially important for lymphocytes during activation and differentiation, as the quantity of secretory cargo increases once the activated cells start to produce and secrete large amounts of cytokines, cytotoxins, or antibodies. However, how the secretory machinery dynamically adapts its efficiency and specificity in general and specifically in lymphocytes remains incompletely understood. Here we present a systematic bioinformatics analysis to address RNA-based mechanisms that control intracellular trafficking and protein secretion during B-lymphocyte activation, and differentiation, with a focus on alternative splicing. Our in silico analyses suggest that alternative splicing has a substantial impact on the dynamic adaptation of intracellular traffic and protein secretion in different B cell subtypes, pointing to another regulatory layer to the control of lymphocyte function during activation and differentiation. Furthermore, we suggest that NERF/ELF2 controls the expression of some COPII-related genes in a cell type-specific manner. In addition, T cells and B cells appear to use different adaptive strategies to adjust their secretory machineries during the generation of effector and memory cells, with antibody secreting B cell specifically increasing the expression of components of the early secretory pathway. Together, our data provide hypotheses how cell type-specific regulation of the trafficking machinery during immune cell activation and differentiation is controlled that can now be tested in wet lab experiments.
Collapse
|
16
|
Jung J, Khan MM, Landry J, Halavatyi A, Machado P, Reiss M, Pepperkok R. Regulation of the COPII secretory machinery via focal adhesions and extracellular matrix signaling. J Cell Biol 2022; 221:213351. [PMID: 35829701 PMCID: PMC9284426 DOI: 10.1083/jcb.202110081] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 05/10/2022] [Accepted: 06/24/2022] [Indexed: 12/19/2022] Open
Abstract
Proteins that enter the secretory pathway are transported from their place of synthesis in the endoplasmic reticulum to the Golgi complex by COPII-coated carriers. The networks of proteins that regulate these components in response to extracellular cues have remained largely elusive. Using high-throughput microscopy, we comprehensively screened 378 cytoskeleton-associated and related proteins for their functional interaction with the coat protein complex II (COPII) components SEC23A and SEC23B. Among these, we identified a group of proteins associated with focal adhesions (FERMT2, MACF1, MAPK8IP2, NGEF, PIK3CA, and ROCK1) that led to the downregulation of SEC23A when depleted by siRNA. Changes in focal adhesions induced by plating cells on ECM also led to the downregulation of SEC23A and decreases in VSVG transport from ER to Golgi. Both the expression of SEC23A and the transport defect could be rescued by treatment with a focal adhesion kinase inhibitor. Altogether, our results identify a network of cytoskeleton-associated proteins connecting focal adhesions and ECM-related signaling with the gene expression of the COPII secretory machinery and trafficking.
Collapse
Affiliation(s)
- Juan Jung
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Muzamil Majid Khan
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany.,Translational Lung Research Center Heidelberg, German Center for Lung Research, Heidelberg, Germany
| | - Jonathan Landry
- Core Facilities Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Aliaksandr Halavatyi
- Core Facilities Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Pedro Machado
- Core Facilities Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Miriam Reiss
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Rainer Pepperkok
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany.,Core Facilities Unit, European Molecular Biology Laboratory, Heidelberg, Germany.,Translational Lung Research Center Heidelberg, German Center for Lung Research, Heidelberg, Germany
| |
Collapse
|
17
|
Carreras-Sureda A, Kroemer G, Cardenas JC, Hetz C. Balancing energy and protein homeostasis at ER-mitochondria contact sites. Sci Signal 2022; 15:eabm7524. [DOI: 10.1126/scisignal.abm7524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The endoplasmic reticulum (ER) is the largest organelle of the cell and participates in multiple essential functions, including the production of secretory proteins, lipid synthesis, and calcium storage. Sustaining proteostasis requires an intimate coupling with energy production. Mitochondrial respiration evolved to be functionally connected to ER physiology through a physical interface between both organelles known as mitochondria-associated membranes. This quasi-synaptic structure acts as a signaling hub that tunes the function of both organelles in a bidirectional manner and controls proteostasis, cell death pathways, and mitochondrial bioenergetics. Here, we discuss the main signaling mechanisms governing interorganellar communication and their putative role in diseases including cancer and neurodegeneration.
Collapse
Affiliation(s)
- Amado Carreras-Sureda
- Department of Cell Physiology and Metabolism, University of Geneva, 1, rue Michel-Servet, 1211 Geneva, Switzerland
| | - Guido Kroemer
- Centre de Recherche des Cordeliers, Equipe labellisée par la Ligue contre le cancer, Université de Paris, Sorbonne Université, Inserm U1138, Institut Universitaire de France, 75006 Paris, France
- Metabolomics and Cell Biology Platforms, Institut Gustave Roussy, 94805 Villejuif, France
- Department of Biology, Institut du Cancer Paris CARPEM, Hôpital Européen Georges Pompidou, AP-HP, 75015 Paris, France
| | - Julio Cesar Cardenas
- Center for Integrative Biology, Mayor University, 7510041 Santiago, Chile
- Center for Geroscience, Brain Health, and Metabolism, 70086 Santiago, Chile
- Buck Institute for Research on Aging, Novato, CA 94945, USA
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Claudio Hetz
- Center for Geroscience, Brain Health, and Metabolism, 70086 Santiago, Chile
- Buck Institute for Research on Aging, Novato, CA 94945, USA
- Faculty of Medicine, Biomedical Neuroscience Institute, University of Chile, 70086 Santiago, Chile
- Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, University of Chile, 70086 Santiago, Chile
| |
Collapse
|
18
|
Li B, Zeng Y, Jiang L. COPII vesicles in plant autophagy and endomembrane trafficking. FEBS Lett 2022; 596:2314-2323. [PMID: 35486434 DOI: 10.1002/1873-3468.14362] [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: 03/11/2022] [Revised: 04/18/2022] [Accepted: 04/19/2022] [Indexed: 11/06/2022]
Abstract
In eukaryotes, the endomembrane system allows for spatiotemporal compartmentation of complicated cellular processes. The plant endomembrane system consists of the endoplasmic reticulum (ER), the Golgi apparatus (GA), the trans-Golgi network (TGN), the multivesicular body (MVB), and the vacuole. Anterograde traffic from the ER to GA is mediated by coat protein complex II (COPII) vesicles. Autophagy, an evolutionarily conserved catabolic process that turns over cellular materials upon nutrient deprivation or in adverse environments, exploits double-membrane autophagosomes to recycle unwanted constituents in the lysosome/vacuole. Accumulating evidence reveals novel functions of plant COPII vesicles in autophagy and their regulation by abiotic stresses. Here, we summarize current knowledge about plant COPII vesicles in the endomembrane trafficking and then highlight recent findings showing their distinct roles in modulating the autophagic flux and stress responses.
Collapse
Affiliation(s)
- Baiying Li
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, New Territories, Hong Kong, China
| | - Yonglun Zeng
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, New Territories, Hong Kong, China
| | - Liwen Jiang
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, New Territories, Hong Kong, China.,CUHK Shenzhen Research Institute, Shenzhen, China.,Institute of Plant Molecular Biology and Agricultural Biotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| |
Collapse
|
19
|
Tanaka T, Moriya K, Tsunenaga M, Yanagawa T, Morita H, Minowa T, Tagawa YI, Hanagata N, Inagaki Y, Ikoma T. Visualized procollagen Iα1 demonstrates the intracellular processing of propeptides. Life Sci Alliance 2022; 5:5/5/e202101060. [PMID: 35181633 PMCID: PMC8860094 DOI: 10.26508/lsa.202101060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 01/26/2022] [Accepted: 01/26/2022] [Indexed: 12/26/2022] Open
Abstract
Procollagen Iα1 with two tags reveals the different fates of processed propeptides, the rate-limiting step in collagen secretion, and a link between defects in intracellular processing and diseases. The processing of type I procollagen is essential for fibril formation; however, the steps involved remain controversial. We constructed a live cell imaging system by inserting fluorescent proteins into type I pre-procollagen α1. Based on live imaging and immunostaining, the C-propeptide is intracellularly cleaved at the perinuclear region, including the endoplasmic reticulum, and subsequently accumulates at the upside of the cell. The N-propeptide is also intracellularly cleaved, but is transported with the repeating structure domain of collagen into the extracellular region. This system makes it possible to detect relative increases and decreases in collagen secretion in a high-throughput manner by assaying fluorescence in the culture medium, and revealed that the rate-limiting step for collagen secretion occurs after the synthesis of procollagen. In the present study, we identified a defect in procollagen processing in activated hepatic stellate cells, which secrete aberrant collagen fibrils. The results obtained demonstrated the intracellular processing of type I procollagen, and revealed a link between dysfunctional processing and diseases such as hepatic fibrosis.
Collapse
Affiliation(s)
- Toshiaki Tanaka
- School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama, Japan
| | - Koji Moriya
- School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama, Japan
| | - Makoto Tsunenaga
- Shiseido Global Innovation Center, 1-2-11 Takashima, Yokohama, Japan
| | - Takayo Yanagawa
- School of Medicine, Tokai University, 143 Shimo-kasuya, Isehara, Japan
| | - Hiromi Morita
- Nanotechnology Innovation Station, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Japan
| | - Takashi Minowa
- Nanotechnology Innovation Station, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Japan
| | - Yoh-Ichi Tagawa
- School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama, Japan
| | - Nobutaka Hanagata
- Nanotechnology Innovation Station, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Japan
| | - Yutaka Inagaki
- School of Medicine, Tokai University, 143 Shimo-kasuya, Isehara, Japan
| | - Toshiyuki Ikoma
- School of Materials and Chemical Technology, Tokyo Institute of Technology, Tokyo, Japan
| |
Collapse
|
20
|
A tango for coats and membranes: New insights into ER-to-Golgi traffic. Cell Rep 2022; 38:110258. [DOI: 10.1016/j.celrep.2021.110258] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 11/17/2021] [Accepted: 12/21/2021] [Indexed: 12/30/2022] Open
|
21
|
Bravo-Plaza I, Hernández-González M, Peñalva MÁ. Comment on Dimou et al. Profile of Membrane Cargo Trafficking Proteins and Transporters Expressed under N Source Derepressing Conditions in Aspergillus nidulans. J. Fungi 2021, 7, 560. J Fungi (Basel) 2021; 7:jof7121037. [PMID: 34947019 PMCID: PMC8703528 DOI: 10.3390/jof7121037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Revised: 11/10/2021] [Accepted: 11/25/2021] [Indexed: 01/02/2023] Open
Abstract
Contrary to the opinion recently offered by Dimou et al., our previously published biochemical, subcellular and genetic data supported our contention that AN11127 corresponds to the A. nidulans gene encoding Sec12, which is the guanine nucleotide exchange factor (GEF) specific for SAR1. We add here additional bioinformatics evidence that fully disprove the otherwise negative evidence reported by Dimou et al., highlighting the dangers associated with the lax interpretation of genomic data. On the positive side, we establish guidelines for the identification of this key secretory gene in other species of Ascomycota and Basidiomycota, including species of medical and applied interest.
Collapse
Affiliation(s)
- Ignacio Bravo-Plaza
- Centro de Investigaciones Biológicas Margarita Salas, CSIC, Ramiro de Maeztu 9, 28049 Madrid, Spain;
| | | | - Miguel Á. Peñalva
- Centro de Investigaciones Biológicas Margarita Salas, CSIC, Ramiro de Maeztu 9, 28049 Madrid, Spain;
- Correspondence:
| |
Collapse
|
22
|
Pereira C, Di Sansebastiano GP. Mechanisms of membrane traffic in plant cells. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2021; 169:102-111. [PMID: 34775176 DOI: 10.1016/j.plaphy.2021.11.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Revised: 10/31/2021] [Accepted: 11/02/2021] [Indexed: 06/13/2023]
Abstract
The organelles of the secretory pathway are characterized by specific organization and function but they communicate in different ways with intense functional crosstalk. The best known membrane-bound transport carriers are known as protein-coated vesicles. Other traffic mechanisms, despite the intense investigations, still show incongruences. The review intends to provide a general view of the mechanisms involved in membrane traffic. We evidence that organelles' biogenesis involves mechanisms that actively operate during the entire cell cycle and the persistent interconnections between the Endoplasmic reticulum (ER), Golgi apparatus, trans-Golgi network (TGN) and endosomes, the vacuolar complex and the plasma membrane (PM) may be seen as a very dynamic membrane network in which vesicular traffic is part of a general maturation process.
Collapse
Affiliation(s)
- Cláudia Pereira
- GreenUPorto-Sustainable Agrifood Production Research Centre & Department of Biology, Faculty of Sciences, University of Porto, Rua Do Campo Alegre, S/nº, 4169-007, Porto, Portugal.
| | - Gian Pietro Di Sansebastiano
- Department of Biological and Environmental Sciences and Technologies (DISTEBA), University of Salento, Campus ECOTEKNE, 73100, Lecce, Italy.
| |
Collapse
|
23
|
MIA3 Splice Defect in Cane Corso Dogs with Dental-Skeletal-Retinal Anomaly (DSRA). Genes (Basel) 2021; 12:genes12101497. [PMID: 34680893 PMCID: PMC8535341 DOI: 10.3390/genes12101497] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 09/24/2021] [Accepted: 09/24/2021] [Indexed: 11/23/2022] Open
Abstract
We investigated a hereditary syndrome in Cane Corso dogs. Affected dogs developed dental-skeletal-retinal anomaly (DSRA), clinically characterized by brittle, discolored, translucent teeth, disproportionate growth and progressive retinal degeneration resulting in vision loss. Combined linkage and homozygosity mapping delineated a 5.8 Mb critical interval. The comparison of whole genome sequence data of an affected dog to 789 control genomes revealed a private homozygous splice region variant in the critical interval. It affected the MIA3 gene encoding the MIA SH3 domain ER export factor 3, which has an essential role in the export of collagen and other secreted proteins. The identified variant, XM_005640835.3:c.3822+3_3822+4del, leads to skipping of two exons from the wild type transcript, XM_005640835.3:r.3712_3822del. Genotypes at the variant were consistent with monogenic autosomal recessive mode of inheritance in a complete family and showed perfect genotype-phenotype association in 18 affected and 22 unaffected Cane Corso dogs. MIA3 variants had previously been shown to cause related phenotypes in humans and mice. Our data in dogs together with the existing functional knowledge of MIA3 variants in other mammalian species suggest the MIA3 splice defect and a near complete loss of gene function as causative molecular pathomechanism for the DSRA phenotype in the investigated dogs.
Collapse
|
24
|
Trafficking to the Cell Surface of Amino Acid Transporter SLC6A14 Upregulated in Cancer Is Controlled by Phosphorylation of SEC24C Protein by AKT Kinase. Cells 2021; 10:cells10071800. [PMID: 34359969 PMCID: PMC8307180 DOI: 10.3390/cells10071800] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 07/07/2021] [Accepted: 07/14/2021] [Indexed: 01/24/2023] Open
Abstract
Cancer cells need a constant supply of nutrients. SLC6A14, an amino acid transporter B0,+ (ATB0,+) that is upregulated in many cancers, transports all but acidic amino acids. In its exit from the endoplasmic reticulum (ER), it is recognized by the SEC24C subunit of coatomer II (COPII) for further vesicular trafficking to the plasma membrane. SEC24C has previously been shown to be phosphorylated by protein kinase B/AKT, which is hyper-activated in cancer; therefore, we analyzed the influence of AKT on SLC6A14 trafficking to the cell surface. Studies on overexpressed and endogenous transporters in the breast cancer cell line MCF-7 showed that AKT inhibition with MK-2206 correlated with a transient increase of the transporter in the plasma membrane, not resulting from the inhibition of ER-associated protein degradation. Two-dimensional electrophoresis demonstrated the decreased phosphorylation of SLC6A14 and SEC24C upon AKT inhibition. A proximity ligation assay confirmed this conclusion: AKT inhibition is correlated with decreased SLC6A14 phosphothreonine and SEC24C phosphoserine. Augmented levels of SLC6A14 in plasma membrane led to increased leucine transport. These results show that the inactivation of AKT can rescue amino acid delivery through SLC6A14 trafficking to the cell surface, supporting cancer cell survival. The regulation of the ER export of the amino acid transporter seems to be a novel function of AKT.
Collapse
|
25
|
Emerging Prospects for Combating Fungal Infections by Targeting Phosphatidylinositol Transfer Proteins. Int J Mol Sci 2021; 22:ijms22136754. [PMID: 34201733 PMCID: PMC8269425 DOI: 10.3390/ijms22136754] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 06/11/2021] [Accepted: 06/11/2021] [Indexed: 12/27/2022] Open
Abstract
The emergence of fungal “superbugs” resistant to the limited cohort of anti-fungal agents available to clinicians is eroding our ability to effectively treat infections by these virulent pathogens. As the threat of fungal infection is escalating worldwide, this dwindling response capacity is fueling concerns of impending global health emergencies. These developments underscore the urgent need for new classes of anti-fungal drugs and, therefore, the identification of new targets. Phosphoinositide signaling does not immediately appear to offer attractive targets due to its evolutionary conservation across the Eukaryota. However, recent evidence argues otherwise. Herein, we discuss the evidence identifying Sec14-like phosphatidylinositol transfer proteins (PITPs) as unexplored portals through which phosphoinositide signaling in virulent fungi can be chemically disrupted with exquisite selectivity. Recent identification of lead compounds that target fungal Sec14 proteins, derived from several distinct chemical scaffolds, reveals exciting inroads into the rational design of next generation Sec14 inhibitors. Development of appropriately refined next generation Sec14-directed inhibitors promises to expand the chemical weaponry available for deployment in the shifting field of engagement between fungal pathogens and their human hosts.
Collapse
|
26
|
Lu J, Gong Y, Wei X, Yao Z, Yang R, Xin J, Gao L, Shao S. Changes in hepatic triglyceride content with the activation of ER stress and increased FGF21 secretion during pregnancy. Nutr Metab (Lond) 2021; 18:40. [PMID: 33849585 PMCID: PMC8045396 DOI: 10.1186/s12986-021-00570-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Accepted: 04/03/2021] [Indexed: 12/15/2022] Open
Abstract
Background To meet the needs of foetal growth and development, marked changes in lipid profiles occur during pregnancy. Abnormal lipid metabolism is often accompanied by adverse pregnancy outcomes, which seriously affect maternal and infant health. Further understanding of the mechanism of lipid metabolism during pregnancy would be helpful to reduce the incidence of adverse pregnancy outcomes. Methods Pregnant mice were euthanized in the virgin (V) state, on day 5 of pregnancy (P5), on day 12 of pregnancy (P12), on day 19 of pregnancy (P19) and on lactation day 2 (L2). Body weight and energy expenditure were assessed to evaluate the general condition of the mice. Triglyceride (TG) levels, the cholesterol content in the liver, liver histopathology, serum lipid profiles, serum β-hydroxybutyrate levels, fibroblast growth factor-21 (FGF21) levels and the levels of relevant target genes were analysed. Results During early pregnancy, anabolism was found to play a major role in liver lipid deposition. In contrast, advanced pregnancy is an overall catabolic condition associated with both increased energy expenditure and reduced lipogenesis. Moreover, the accumulation of hepatic TG did not appear until P12, after the onset of endoplasmic reticulum (ER) stress on P5. Then, catabolism was enhanced, and FGF21 secretion was increased in the livers of female mice in late pregnancy. We further found that the expression of sec23a, which as the coat protein complex II (COPII) vesicle coat proteins regulates the secretion of FGF21, in the liver was decreased on P19. Conclusion With the activation of ER stress and increased FGF21 secretion during pregnancy, the hepatic TG content changes, suggesting that ER stress and FGF21 may play an important role in balancing lipid homeostasis and meeting maternal and infant energy requirements in late pregnancy.
Collapse
Affiliation(s)
- Jiayu Lu
- Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, 544, Jing 4 Rd., Jinan, 250021, Shandong, China.,Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Jinan, 250021, Shandong, China.,Shandong Institute of Endocrine and Metabolic Disease, Jinan, 250021, Shandong, China
| | - Ying Gong
- Department of Endocrinology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, 250021, Shandong, China.,Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Jinan, 250021, Shandong, China.,Shandong Institute of Endocrine and Metabolic Disease, Jinan, 250021, Shandong, China
| | - Xinhong Wei
- Shandong Medical Imaging Research Institute, Shandong University, Jinan, 250021, Shandong, China
| | - Zhenyu Yao
- Department of Endocrinology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, 250021, Shandong, China.,Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Jinan, 250021, Shandong, China.,Shandong Institute of Endocrine and Metabolic Disease, Jinan, 250021, Shandong, China
| | - Rui Yang
- Experimental Animal Center, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, 250021, Shandong, China
| | - Jinxing Xin
- Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, 544, Jing 4 Rd., Jinan, 250021, Shandong, China.,Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Jinan, 250021, Shandong, China.,Shandong Institute of Endocrine and Metabolic Disease, Jinan, 250021, Shandong, China
| | - Ling Gao
- Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Jinan, 250021, Shandong, China.,Shandong Institute of Endocrine and Metabolic Disease, Jinan, 250021, Shandong, China.,Scientific Center, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, 250021, Shandong, China
| | - Shanshan Shao
- Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, 544, Jing 4 Rd., Jinan, 250021, Shandong, China. .,Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Jinan, 250021, Shandong, China. .,Shandong Institute of Endocrine and Metabolic Disease, Jinan, 250021, Shandong, China.
| |
Collapse
|
27
|
Gomez-Navarro N, Melero A, Li XH, Boulanger J, Kukulski W, Miller EA. Cargo crowding contributes to sorting stringency in COPII vesicles. J Cell Biol 2021; 219:151777. [PMID: 32406500 PMCID: PMC7300426 DOI: 10.1083/jcb.201806038] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 03/11/2020] [Accepted: 04/24/2020] [Indexed: 02/05/2023] Open
Abstract
Accurate maintenance of organelle identity in the secretory pathway relies on retention and retrieval of resident proteins. In the endoplasmic reticulum (ER), secretory proteins are packaged into COPII vesicles that largely exclude ER residents and misfolded proteins by mechanisms that remain unresolved. Here we combined biochemistry and genetics with correlative light and electron microscopy (CLEM) to explore how selectivity is achieved. Our data suggest that vesicle occupancy contributes to ER retention: in the absence of abundant cargo, nonspecific bulk flow increases. We demonstrate that ER leakage is influenced by vesicle size and cargo occupancy: overexpressing an inert cargo protein or reducing vesicle size restores sorting stringency. We propose that cargo recruitment into vesicles creates a crowded lumen that drives selectivity. Retention of ER residents thus derives in part from the biophysical process of cargo enrichment into a constrained spherical membrane-bound carrier.
Collapse
Affiliation(s)
| | - Alejandro Melero
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Xiao-Han Li
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Jérôme Boulanger
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Wanda Kukulski
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | | |
Collapse
|
28
|
Hernandez-Gonzalez M, Larocque G, Way M. Viral use and subversion of membrane organization and trafficking. J Cell Sci 2021; 134:jcs252676. [PMID: 33664154 PMCID: PMC7610647 DOI: 10.1242/jcs.252676] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Membrane trafficking is an essential cellular process conserved across all eukaryotes, which regulates the uptake or release of macromolecules from cells, the composition of cellular membranes and organelle biogenesis. It influences numerous aspects of cellular organisation, dynamics and homeostasis, including nutrition, signalling and cell architecture. Not surprisingly, malfunction of membrane trafficking is linked to many serious genetic, metabolic and neurological disorders. It is also often hijacked during viral infection, enabling viruses to accomplish many of the main stages of their replication cycle, including entry into and egress from cells. The appropriation of membrane trafficking by viruses has been studied since the birth of cell biology and has helped elucidate how this integral cellular process functions. In this Review, we discuss some of the different strategies viruses use to manipulate and take over the membrane compartments of their hosts to promote their replication, assembly and egress.
Collapse
Affiliation(s)
- Miguel Hernandez-Gonzalez
- Cellular Signalling and Cytoskeletal Function Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Gabrielle Larocque
- Cellular Signalling and Cytoskeletal Function Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Michael Way
- Cellular Signalling and Cytoskeletal Function Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
- Department of Infectious Disease, Imperial College, London W2 1PG, UK
| |
Collapse
|
29
|
Virlogeux A, Scaramuzzino C, Lenoir S, Carpentier R, Louessard M, Genoux A, Lino P, Hinckelmann MV, Perrier AL, Humbert S, Saudou F. Increasing brain palmitoylation rescues behavior and neuropathology in Huntington disease mice. SCIENCE ADVANCES 2021; 7:7/14/eabb0799. [PMID: 33789888 PMCID: PMC8011966 DOI: 10.1126/sciadv.abb0799] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 02/11/2021] [Indexed: 05/02/2023]
Abstract
Huntington disease (HD) damages the corticostriatal circuitry in large part by impairing transport of brain-derived neurotrophic factor (BDNF). We hypothesized that improving vesicular transport of BDNF could slow or prevent disease progression. We therefore performed selective proteomic analysis of vesicles transported within corticostriatal projecting neurons followed by in silico screening and identified palmitoylation as a pathway that could restore defective huntingtin-dependent trafficking. Using a synchronized trafficking assay and an HD network-on-a-chip, we found that increasing brain palmitoylation via ML348, which inhibits the palmitate-removing enzyme acyl-protein thioesterase 1 (APT1), restores axonal transport, synapse homeostasis, and survival signaling to wild-type levels without toxicity. In human HD induced pluripotent stem cell-derived cortical neurons, ML348 increased BDNF trafficking. In HD knock-in mice, it efficiently crossed the blood-brain barrier to restore palmitoylation levels and reverse neuropathology, locomotor deficits, and anxio-depressive behaviors. APT1 and its inhibitor ML348 thus hold therapeutic interest for HD.
Collapse
Affiliation(s)
- Amandine Virlogeux
- Univ. Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut Neuroscience, GIN, 38000, Grenoble, France
| | - Chiara Scaramuzzino
- Univ. Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut Neuroscience, GIN, 38000, Grenoble, France
| | - Sophie Lenoir
- Univ. Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut Neuroscience, GIN, 38000, Grenoble, France
| | - Rémi Carpentier
- Univ. Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut Neuroscience, GIN, 38000, Grenoble, France
| | | | - Aurélie Genoux
- Univ. Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut Neuroscience, GIN, 38000, Grenoble, France
| | - Patricia Lino
- INSERM U861, UEVE, I-STEM, AFM, 91100, Corbeil-Essonnes, France
| | - Maria-Victoria Hinckelmann
- Univ. Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut Neuroscience, GIN, 38000, Grenoble, France
| | - Anselme L Perrier
- INSERM U861, UEVE, I-STEM, AFM, 91100, Corbeil-Essonnes, France
- Commissariat à l'Énergie Atomique et aux Énergies Alternatives (CEA), Direction de la Recherche Fondamentale, Institut François Jacob, Molecular Imaging Center (MIRCen), CNRS UMR 9199, Université Paris-Saclay, 92265, Fontenay-aux-Roses, France
| | - Sandrine Humbert
- Univ. Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut Neuroscience, GIN, 38000, Grenoble, France
| | - Frédéric Saudou
- Univ. Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut Neuroscience, GIN, 38000, Grenoble, France.
| |
Collapse
|
30
|
Nakamura A, Boroojeni SF, Haroon N. Aberrant antigen processing and presentation: Key pathogenic factors leading to immune activation in Ankylosing spondylitis. Semin Immunopathol 2021; 43:245-253. [PMID: 33532928 DOI: 10.1007/s00281-020-00833-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Accepted: 12/18/2020] [Indexed: 12/12/2022]
Abstract
The strong association of HLA-B*27 with ankylosing spondylitis (AS) was first reported nearly 50 years ago. However, the mechanistic link between HLA-B*27 and AS has remained an enigma. While 85-90% of AS patients possess HLA-B*27, majority of HLA-B*27 healthy individuals do not develop AS. This suggests that additional genes and genetic regions interplay with HLA-B*27 to cause AS. Previous genome-wide association studies (GWAS) identified key genes that are distinctively expressed in AS, including the Endoplasmic Reticulum Aminopeptidase (ERAP) 1 and ERAP2. As these gene-encoding molecules are primarily implicated in the process of peptide processing and presentation, potential pathological interaction of these molecules with HLA-B*27 may operate to cause AS by activating downstream immune responses. The aberrant peptide processing also gives rise to the accumulation of unstable protein complex in endoplasmic reticulum (ER), which drives endoplasmic reticulum-associated protein degradation (ERAD) and unfolded protein response (UPR) and activates autophagy. In this review, we describe the current hypotheses of AS pathogenesis, focusing on antigen processing and presentation operated by HLA-B*27 and associated molecules that may contribute to the disease initiation and progression of AS.
Collapse
Affiliation(s)
- Akihiro Nakamura
- Schroeder Arthritis Institute, University Health Network, Toronto, Ontario, Canada.,Spondylitis Program, University Health Network, Toronto, Ontario, Canada.,Division of Genetics and Development, Krembil Research Institute, University Health Network, 60 Leonard Avenue, Toronto, Ontario, M5T 2S8, Canada.,Division of Rheumatology, Toronto Western Hospital, University Health Network, Toronto, Ontario, Canada.,Institute of Medical Science, Department of Medicine, University of Toronto, 399 Bathurst Street, Toronto, Ontario, M5T 2S8, Canada
| | - Shaghayegh Foroozan Boroojeni
- Schroeder Arthritis Institute, University Health Network, Toronto, Ontario, Canada.,Spondylitis Program, University Health Network, Toronto, Ontario, Canada.,Division of Genetics and Development, Krembil Research Institute, University Health Network, 60 Leonard Avenue, Toronto, Ontario, M5T 2S8, Canada.,Institute of Medical Science, Department of Medicine, University of Toronto, 399 Bathurst Street, Toronto, Ontario, M5T 2S8, Canada
| | - Nigil Haroon
- Schroeder Arthritis Institute, University Health Network, Toronto, Ontario, Canada. .,Spondylitis Program, University Health Network, Toronto, Ontario, Canada. .,Division of Genetics and Development, Krembil Research Institute, University Health Network, 60 Leonard Avenue, Toronto, Ontario, M5T 2S8, Canada. .,Division of Rheumatology, Toronto Western Hospital, University Health Network, Toronto, Ontario, Canada. .,Institute of Medical Science, Department of Medicine, University of Toronto, 399 Bathurst Street, Toronto, Ontario, M5T 2S8, Canada.
| |
Collapse
|
31
|
Kim S, Khoriaty R, Li L, McClune M, Kalfa TA, Wu J, Peltier D, Fujiwara H, Sun Y, Oravecz-Wilson K, King RA, Ginsburg D, Reddy P. ER-to-Golgi transport and SEC23-dependent COPII vesicles regulate T cell alloimmunity. J Clin Invest 2021; 131:136574. [PMID: 33463537 DOI: 10.1172/jci136574] [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: 01/21/2020] [Accepted: 11/12/2020] [Indexed: 01/24/2023] Open
Abstract
T cell-mediated responses are dependent on their secretion of key effector molecules. However, the critical molecular determinants of the secretion of these proteins are largely undefined. Here, we demonstrate that T cell activation increases trafficking via the ER-to-Golgi pathway. To study the functional role of this pathway, we generated mice with a T cell-specific deletion in SEC23B, a core subunit of coat protein complex II (COPII). We found that SEC23B critically regulated the T cell secretome following activation. SEC23B-deficient T cells exhibited a proliferative defect and reduced effector functions in vitro, as well as in experimental models of allogeneic and xenogeneic hematopoietic cell transplantation in vivo. However, T cells derived from 3 patients with congenital dyserythropoietic anemia II (CDAII), which results from Sec23b mutation, did not exhibit a similar phenotype. Mechanistic studies demonstrated that unlike murine KO T cells, T cells from patients with CDAII harbor increased levels of the closely related paralog, SEC23A. In vivo rescue of murine KO by expression of Sec23a from the Sec23b genomic locus restored T cell functions. Together, our data demonstrate a critical role for the COPII pathway, with evidence for functional overlap in vivo between SEC23 paralogs in the regulation of T cell immunity in both mice and humans.
Collapse
Affiliation(s)
- Stephanie Kim
- Department of Internal Medicine, Division of Hematology and Oncology.,Medical Scientist Training Program, and
| | - Rami Khoriaty
- Department of Internal Medicine, Division of Hematology and Oncology.,Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Lu Li
- Department of Internal Medicine, Division of Hematology and Oncology
| | - Madison McClune
- Department of Internal Medicine, Division of Hematology and Oncology
| | - Theodosia A Kalfa
- Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Julia Wu
- Department of Internal Medicine, Division of Hematology and Oncology.,Medical Scientist Training Program, and
| | - Daniel Peltier
- Department of Pediatrics, Division of Hematology and Oncology
| | - Hideaki Fujiwara
- Department of Internal Medicine, Division of Hematology and Oncology
| | - Yaping Sun
- Department of Internal Medicine, Division of Hematology and Oncology
| | | | - Richard A King
- Department of Internal Medicine, Division of Hematology and Oncology
| | - David Ginsburg
- Department of Internal Medicine, Division of Hematology and Oncology.,Department of Pediatrics, Division of Hematology and Oncology.,Department of Human Genetics.,Life Sciences Institute.,Howard Hughes Medical Institute, and.,Department of Internal Medicine, Division of Genetic Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Pavan Reddy
- Department of Internal Medicine, Division of Hematology and Oncology
| |
Collapse
|
32
|
Clark EM, Link BA. Complementary and divergent functions of zebrafish Tango1 and Ctage5 in tissue development and homeostasis. Mol Biol Cell 2021; 32:391-401. [PMID: 33439675 PMCID: PMC8098853 DOI: 10.1091/mbc.e20-11-0745] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Coat protein complex II (COPII) factors mediate cargo export from the endoplasmic reticulum (ER), but bulky collagens and lipoproteins are too large for traditional COPII vesicles. Mammalian CTAGE5 and TANGO1 have been well characterized individually as specialized cargo receptors at the ER that function with COPII coats to facilitate trafficking of bulky cargoes. Here, we present a genetic interaction study in zebrafish of deletions in ctage5, tango1, or both to investigate their distinct and complementary potential functions. We found that Ctage5 and Tango1 have different roles related to organogenesis, collagen versus lipoprotein trafficking, stress-pathway activation, and survival. While disruption of both ctage5 and tango1 compounded phenotype severity, mutation of either factor alone revealed novel tissue-specific defects in the building of heart, muscle, lens, and intestine, in addition to previously described roles in the development of neural and cartilage tissues. Together, our results demonstrate that Ctage5 and Tango1 have overlapping functions, but also suggest divergent roles in tissue development and homeostasis.
Collapse
Affiliation(s)
- Eric M Clark
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226
| | - Brian A Link
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226
| |
Collapse
|
33
|
Bisnett BJ, Condon BM, Lamb CH, Georgiou GR, Boyce M. Export Control: Post-transcriptional Regulation of the COPII Trafficking Pathway. Front Cell Dev Biol 2021; 8:618652. [PMID: 33511128 PMCID: PMC7835409 DOI: 10.3389/fcell.2020.618652] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Accepted: 12/14/2020] [Indexed: 11/13/2022] Open
Abstract
The coat protein complex II (COPII) mediates forward trafficking of protein and lipid cargoes from the endoplasmic reticulum. COPII is an ancient and essential pathway in all eukaryotes and COPII dysfunction underlies a range of human diseases. Despite this broad significance, major aspects of COPII trafficking remain incompletely understood. For example, while the biochemical features of COPII vesicle formation are relatively well characterized, much less is known about how the COPII system dynamically adjusts its activity to changing physiologic cues or stresses. Recently, post-transcriptional mechanisms have emerged as a major mode of COPII regulation. Here, we review the current literature on how post-transcriptional events, and especially post-translational modifications, govern the COPII pathway.
Collapse
Affiliation(s)
- Brittany J Bisnett
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, United States
| | - Brett M Condon
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, United States
| | - Caitlin H Lamb
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, United States
| | - George R Georgiou
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, United States
| | - Michael Boyce
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, United States
| |
Collapse
|
34
|
Mohan HM, Yang B, Dean NA, Raghavan M. Calreticulin enhances the secretory trafficking of a misfolded α-1-antitrypsin. J Biol Chem 2020; 295:16754-16772. [PMID: 32978262 PMCID: PMC7864070 DOI: 10.1074/jbc.ra120.014372] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 09/12/2020] [Indexed: 01/24/2023] Open
Abstract
α1-antitrypsin (AAT) regulates the activity of multiple proteases in the lungs and liver. A mutant of AAT (E342K) called ATZ forms polymers that are present at only low levels in the serum and induce intracellular protein inclusions, causing lung emphysema and liver cirrhosis. An understanding of factors that can reduce the intracellular accumulation of ATZ is of great interest. We now show that calreticulin (CRT), an endoplasmic reticulum (ER) glycoprotein chaperone, promotes the secretory trafficking of ATZ, enhancing the media:cell ratio. This effect is more pronounced for ATZ than with AAT and is only partially dependent on the glycan-binding site of CRT, which is generally relevant to substrate recruitment and folding by CRT. The CRT-related chaperone calnexin does not enhance ATZ secretory trafficking, despite the higher cellular abundance of calnexin-ATZ complexes. CRT deficiency alters the distributions of ATZ-ER chaperone complexes, increasing ATZ-BiP binding and inclusion body formation and reducing ATZ interactions with components required for ER-Golgi trafficking, coincident with reduced levels of the protein transport protein Sec31A in CRT-deficient cells. These findings indicate a novel role for CRT in promoting the secretory trafficking of a protein that forms polymers and large intracellular inclusions. Inefficient secretory trafficking of ATZ in the absence of CRT is coincident with enhanced accumulation of ER-derived ATZ inclusion bodies. Further understanding of the factors that control the secretory trafficking of ATZ and their regulation by CRT could lead to new therapies for lung and liver diseases linked to AAT deficiency.
Collapse
Affiliation(s)
- Harihar Milaganur Mohan
- Department of Microbiology and Immunology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, 48109 USA
| | - Boning Yang
- Department of Microbiology and Immunology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, 48109 USA
| | - Nicole A Dean
- Department of Microbiology and Immunology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, 48109 USA
| | - Malini Raghavan
- Department of Microbiology and Immunology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, 48109 USA.
| |
Collapse
|
35
|
A nanobody suite for yeast scaffold nucleoporins provides details of the nuclear pore complex structure. Nat Commun 2020; 11:6179. [PMID: 33268786 PMCID: PMC7710722 DOI: 10.1038/s41467-020-19884-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 10/30/2020] [Indexed: 01/07/2023] Open
Abstract
Nuclear pore complexes (NPCs) are the main conduits for molecular exchange across the nuclear envelope. The NPC is a modular assembly of ~500 individual proteins, called nucleoporins or nups. Most scaffolding nups are organized in two multimeric subcomplexes, the Nup84 or Y complex and the Nic96 or inner ring complex. Working in S. cerevisiae, and to study the assembly of these two essential subcomplexes, we here develop a set of twelve nanobodies that recognize seven constituent nucleoporins of the Y and Nic96 complexes. These nanobodies all bind specifically and with high affinity. We present structures of several nup-nanobody complexes, revealing their binding sites. Additionally, constitutive expression of the nanobody suite in S. cerevisiae detect accessible and obstructed surfaces of the Y complex and Nic96 within the NPC. Overall, this suite of nanobodies provides a unique and versatile toolkit for the study of the NPC.
Collapse
|
36
|
ER functions are exploited by viruses to support distinct stages of their life cycle. Biochem Soc Trans 2020; 48:2173-2184. [PMID: 33119046 DOI: 10.1042/bst20200395] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Revised: 09/29/2020] [Accepted: 10/05/2020] [Indexed: 02/07/2023]
Abstract
The endoplasmic reticulum (ER), with its expansive membranous system and a vast network of chaperones, enzymes, sensors, and ion channels, orchestrates diverse cellular functions, ranging from protein synthesis, folding, secretion, and degradation to lipid biogenesis and calcium homeostasis. Strikingly, some of the functions of the ER are exploited by viruses to promote their life cycles. During entry, viruses must penetrate a host membrane and reach an intracellular destination to express and replicate their genomes. These events lead to the assembly of new viral progenies that exit the host cell, thereby initiating further rounds of infection. In this review, we highlight how three distinct viruses - polyomavirus, flavivirus, and coronavirus - co-opt key functions of the ER to cause infection. We anticipate that illuminating this virus-ER interplay will provide rational therapeutic approaches to combat the virus-induced diseases.
Collapse
|
37
|
Raote I, Chabanon M, Walani N, Arroyo M, Garcia-Parajo MF, Malhotra V, Campelo F. A physical mechanism of TANGO1-mediated bulky cargo export. eLife 2020; 9:e59426. [PMID: 33169667 PMCID: PMC7704110 DOI: 10.7554/elife.59426] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 11/09/2020] [Indexed: 01/08/2023] Open
Abstract
The endoplasmic reticulum (ER)-resident protein TANGO1 assembles into a ring around ER exit sites (ERES), and links procollagens in the ER lumen to COPII machinery, tethers, and ER-Golgi intermediate compartment (ERGIC) in the cytoplasm (Raote et al., 2018). Here, we present a theoretical approach to investigate the physical mechanisms of TANGO1 ring assembly and how COPII polymerization, membrane tension, and force facilitate the formation of a transport intermediate for procollagen export. Our results indicate that a TANGO1 ring, by acting as a linactant, stabilizes the open neck of a nascent COPII bud. Elongation of such a bud into a transport intermediate commensurate with bulky procollagens is then facilitated by two complementary mechanisms: (i) by relieving membrane tension, possibly by TANGO1-mediated fusion of retrograde ERGIC membranes and (ii) by force application. Altogether, our theoretical approach identifies key biophysical events in TANGO1-driven procollagen export.
Collapse
Affiliation(s)
- Ishier Raote
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and TechnologyBarcelonaSpain
| | - Morgan Chabanon
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and TechnologyBarcelonaSpain
- Universitat Politècnica de Catalunya-BarcelonaTechBarcelonaSpain
| | - Nikhil Walani
- Universitat Politècnica de Catalunya-BarcelonaTechBarcelonaSpain
| | - Marino Arroyo
- Universitat Politècnica de Catalunya-BarcelonaTechBarcelonaSpain
- Institute for Bioengineering of Catalonia, The Barcelona Institute of Science and TechnologyBarcelonaSpain
- Centre Internacional de Mètodes Numèrics en Enginyeria (CIMNE)BarcelonaSpain
| | - Maria F Garcia-Parajo
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and TechnologyBarcelonaSpain
- ICREABarcelonaSpain
| | - Vivek Malhotra
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and TechnologyBarcelonaSpain
- ICREABarcelonaSpain
- Universitat Pompeu Fabra (UPF)BarcelonaSpain
| | - Felix Campelo
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and TechnologyBarcelonaSpain
| |
Collapse
|
38
|
Nałęcz KA. Amino Acid Transporter SLC6A14 (ATB 0,+) - A Target in Combined Anti-cancer Therapy. Front Cell Dev Biol 2020; 8:594464. [PMID: 33195271 PMCID: PMC7609839 DOI: 10.3389/fcell.2020.594464] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 09/30/2020] [Indexed: 12/12/2022] Open
Abstract
Cancer cells are characterized by quick growth and proliferation, demanding constant supply of various nutrients. Several plasma membrane transporters delivering such compounds are upregulated in cancer. Solute carrier family 6 member 14 (SLC6A14), known as amino acid transporter B0,+ (ATB0,+) transports all amino acids with exception of the acidic ones: aspartate and glutamate. Its malfunctioning is correlated with several pathological states and it is upregulated in solid tumors. The high expression of SLC6A14 is prognostic and unfavorable in pancreatic cancer, while in breast cancer it is expressed in estrogen receptor positive cells. As many plasma membrane transporters it resides in endoplasmic reticulum (ER) membrane after translation before further trafficking through Golgi to the cell surface. Transporter exit from ER is strictly controlled. The proper folding of SLC6A14 was shown to be controlled from the cytoplasmic side by heat shock proteins, further exit from ER and formation of coatomer II (COPII) coated vesicles depends on specific interaction with COPII cargo-recognizing subunit SEC24C, phosphorylated by kinase AKT. Inhibition of heat shock proteins, known to be upregulated in cancer, directs SLC6A14 to degradation. Targeting proteins regulating SLC6A14 trafficking is proposed as an additional pharmacological treatment of cancer.
Collapse
Affiliation(s)
- Katarzyna A Nałęcz
- Laboratory of Transport Through Biomembranes, Nencki Institute of Experimental Biology, Warsaw, Poland
| |
Collapse
|
39
|
Mitotic ER Exit Site Disassembly and Reassembly Are Regulated by the Phosphorylation Status of TANGO1. Dev Cell 2020; 55:237-250.e5. [DOI: 10.1016/j.devcel.2020.07.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 06/24/2020] [Accepted: 07/22/2020] [Indexed: 11/20/2022]
|
40
|
Long M, Kranjc T, Mysior MM, Simpson JC. RNA Interference Screening Identifies Novel Roles for RhoBTB1 and RhoBTB3 in Membrane Trafficking Events in Mammalian Cells. Cells 2020; 9:cells9051089. [PMID: 32354068 PMCID: PMC7291084 DOI: 10.3390/cells9051089] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 04/22/2020] [Accepted: 04/25/2020] [Indexed: 12/19/2022] Open
Abstract
In the endomembrane system of mammalian cells, membrane traffic processes require a high degree of regulation in order to ensure their specificity. The range of molecules that participate in trafficking events is truly vast, and much attention to date has been given to the Rab family of small GTPases. However, in recent years, a role in membrane traffic for members of the Rho GTPase family, in particular Cdc42, has emerged. This prompted us to develop and apply an image-based high-content screen, initially focussing on the Golgi complex, using RNA interference to systematically perturb each of the 21 Rho family members and assess their importance to the overall organisation of this organelle. Analysis of our data revealed previously unreported roles for two atypical Rho family members, RhoBTB1 and RhoBTB3, in membrane traffic events. We find that depletion of RhoBTB3 affects the morphology of the Golgi complex and causes changes in the trafficking speeds of carriers operating at the interface of the Golgi and endoplasmic reticulum. In addition, RhoBTB3 was found to be present on these carriers. Depletion of RhoBTB1 was also found to cause a disturbance to the Golgi architecture, however, this phenotype seems to be linked to endocytosis and retrograde traffic pathways. RhoBTB1 was found to be associated with early endosomal intermediates, and changes in the levels of RhoBTB1 not only caused profound changes to the organisation and distribution of endosomes and lysosomes, but also resulted in defects in the delivery of two different classes of cargo molecules to downstream compartments. Together, our data reveal new roles for these atypical Rho family members in the endomembrane system.
Collapse
|
41
|
Lekszas C, Foresti O, Raote I, Liedtke D, König EM, Nanda I, Vona B, De Coster P, Cauwels R, Malhotra V, Haaf T. Biallelic TANGO1 mutations cause a novel syndromal disease due to hampered cellular collagen secretion. eLife 2020; 9:51319. [PMID: 32101163 PMCID: PMC7062462 DOI: 10.7554/elife.51319] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Accepted: 02/24/2020] [Indexed: 12/15/2022] Open
Abstract
The transport and Golgi organization 1 (TANGO1) proteins play pivotal roles in the secretory pathway. Full length TANGO1 is a transmembrane protein localised at endoplasmic reticulum (ER) exit sites, where it binds bulky cargo within the ER lumen and recruits membranes from the ER Golgi intermediate compartment to create an exit route for their export. Here we report the first TANGO1-associated syndrome in humans. A synonymous substitution that results in exon eight skipping in most mRNA molecules, ultimately leading to a truncated TANGO1 protein was identified as disease-causing mutation. The four homozygously affected sons of a consanguineous family display severe dentinogenesis imperfecta, short stature, various skeletal abnormalities, insulin-dependent diabetes mellitus, sensorineural hearing loss, and mild intellectual disability. Functional studies in HeLa and U2OS cells revealed that the corresponding truncated TANGO1 protein is dispersed in the ER and its expression in cells with intact endogenous TANGO1 impairs cellular collagen I secretion.
Collapse
Affiliation(s)
- Caroline Lekszas
- Institute of Human Genetics, Julius Maximilians University Würzburg, Würzburg, Germany
| | - Ombretta Foresti
- Centre for Genomic Regulation, The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Ishier Raote
- Centre for Genomic Regulation, The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Daniel Liedtke
- Institute of Human Genetics, Julius Maximilians University Würzburg, Würzburg, Germany
| | - Eva-Maria König
- Institute of Human Genetics, Julius Maximilians University Würzburg, Würzburg, Germany
| | - Indrajit Nanda
- Institute of Human Genetics, Julius Maximilians University Würzburg, Würzburg, Germany
| | - Barbara Vona
- Institute of Human Genetics, Julius Maximilians University Würzburg, Würzburg, Germany.,Department of Otorhinolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre (THRC), Eberhard Karls University Tübingen, Tübingen, Germany
| | - Peter De Coster
- Department of Pediatric Dentistry and Special Care, PaeCoMeDis Research Group, Ghent University Hospital, Ghent, Belgium
| | - Rita Cauwels
- Department of Pediatric Dentistry and Special Care, PaeCoMeDis Research Group, Ghent University Hospital, Ghent, Belgium
| | - Vivek Malhotra
- Centre for Genomic Regulation, The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Thomas Haaf
- Institute of Human Genetics, Julius Maximilians University Würzburg, Würzburg, Germany
| |
Collapse
|
42
|
Zeyen L, Döring T, Stieler JT, Prange R. Hepatitis B subviral envelope particles use the COPII machinery for intracellular transport via selective exploitation of Sec24A and Sec23B. Cell Microbiol 2020; 22:e13181. [PMID: 32017353 DOI: 10.1111/cmi.13181] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 01/18/2020] [Accepted: 01/28/2020] [Indexed: 12/12/2022]
Abstract
Hepatitis B virus (HBV) is a leading cause of liver disease. Its success as a human pathogen is related to the immense production of subviral envelope particles (SVPs) contributing to viral persistence by interfering with immune functions. To explore cellular pathways involved in SVP formation and egress, we investigated host-pathogen interactions. Yeast-based proteomics revealed Sec24A, a component of the coat protein complex II (COPII), as an interaction partner of the HBV envelope S domain. To understand how HBV co-opts COPII as a proviral machinery, we studied roles of key Sec proteins in HBV-expressing liver cells. Silencing of Sar1, Sec23, and Sec24, which promote COPII assembly concomitant with cargo loading, strongly diminished endoplasmic reticulum (ER) envelope export and SVP secretion. By analysing Sec paralog specificities, we unexpectedly found that the HBV envelope is a selective interaction partner of Sec24A and Sec23B whose functions could not be substituted by their related isoforms. In support, we found that HBV replication upregulated Sec24A and Sec23B transcription. Furthermore, HBV encountered the Sec24A/Sec23B complex via an interaction that involved the N-terminal half of Sec24A and a di-arginine motif of its S domain, mirroring a novel ER export code. Accordingly, an interference with the COPII/HBV cross-talk might display a tool to effectively inhibit SVP release.
Collapse
Affiliation(s)
- Lisa Zeyen
- Department of Virology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Tatjana Döring
- Department of Virology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Jens T Stieler
- Department of Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute of Brain Research, University of Leipzig, Leipzig, Germany
| | - Reinhild Prange
- Department of Virology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| |
Collapse
|
43
|
Bagchi P. Endoplasmic reticulum in viral infection. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2019; 350:265-284. [PMID: 32138901 DOI: 10.1016/bs.ircmb.2019.10.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Virus exploits host cellular machinery to replicate and form new viral progeny and endoplasmic reticulum (ER) plays central role in the interplay between virus and host cell. Here I will discuss how cellular functions of ER being utilized by viruses from different families during different stages of pathogenesis. Flow of knowledge related to this area of research based on interdisciplinary approach, using biochemical and cell biological assays coupled with advanced microscopy strategies, is pushing our understanding of the virus-ER interaction during infection to the next level.
Collapse
Affiliation(s)
- Parikshit Bagchi
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, United States.
| |
Collapse
|
44
|
Saito K, Maeda M. Not just a cargo receptor for large cargoes; an emerging role of TANGO1 as an organizer of ER exit sites. J Biochem 2019; 166:115-119. [PMID: 31098622 DOI: 10.1093/jb/mvz036] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Accepted: 04/24/2019] [Indexed: 02/07/2023] Open
Abstract
Proteins synthesized within the endoplasmic reticulum (ER) are exported from ER exit sites via coat protein complex II (COPII)-coated vesicles. Although the mechanisms of COPII-vesicle formation at the ER exit sites are highly conserved among species, vertebrate cells secrete a wide range of materials, including collagens and chylomicrons, which form bulky structures within the ER that are too large to fit into conventional carriers. Transport ANd Golgi Organization 1 (TANGO1) was initially identified as a cargo receptor for collagens but has been recently rediscovered as an organizer of ER exit sites. We would like to review recent advances in the mechanism of large cargo secretion and organization of ER exit sites through the function of TANGO1.
Collapse
Affiliation(s)
- Kota Saito
- Department of Biological Informatics and Experimental Therapeutics, Graduate School of Medicine, Akita University, 1-1-1 Hondo, Akita, Japan
| | - Miharu Maeda
- Department of Biological Informatics and Experimental Therapeutics, Graduate School of Medicine, Akita University, 1-1-1 Hondo, Akita, Japan
| |
Collapse
|
45
|
Identification of the guanine nucleotide exchange factor for SAR1 in the filamentous fungal model Aspergillus nidulans. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2019; 1866:118551. [PMID: 31487505 DOI: 10.1016/j.bbamcr.2019.118551] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 08/02/2019] [Accepted: 08/11/2019] [Indexed: 12/30/2022]
Abstract
In spite of its basic and applied interest, the regulation of ER exit by filamentous fungi is insufficiently understood. In previous work we isolated a panel of conditional mutations in sarA encoding the master GTPase SarASAR1 in A. nidulans and demonstrated its key role in exocytosis and hyphal morphogenesis. However, the SAR1 guanine nucleotide exchange factor (GEF), Sec12, has not been characterized in any filamentous fungus, largely due to the fact that SEC12 homologues share little amino acid sequence identity beyond a GGGGxxxxGϕxN motif involved in guanine nucleotide exchange. Here we demonstrate that AN11127 encodes A. nidulans Sec12, which is an essential protein that localizes to the ER and that, when overexpressed, rescues the growth defect resulting from a hypomorphic sarA6ts mutation at 37 °C. Using purified, bacterially expressed proteins we demonstrate that the product of AN11127 accelerates nucleotide exchange on SarASAR1, but not on its closely related GTPase ArfAARF1, as expected for a bona fide GEF. The unequivocal characterization of A. nidulans Sec12 paves the way for the tailored modification of ER exit in a model organism that is closely related to industrial species of filamentous fungi.
Collapse
|
46
|
Zhang C, Rabouille C. Membrane-Bound Meet Membraneless in Health and Disease. Cells 2019; 8:cells8091000. [PMID: 31470564 PMCID: PMC6770257 DOI: 10.3390/cells8091000] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 08/26/2019] [Accepted: 08/27/2019] [Indexed: 12/12/2022] Open
Abstract
Membraneless organelles (MLOs) are defined as cellular structures that are not sealed by a lipidic membrane and are shown to form by phase separation. They exist in both the nucleus and the cytoplasm that is also heavily populated by numerous membrane-bound organelles. Even though the name membraneless suggests that MLOs are free of membrane, both membrane and factors regulating membrane trafficking steps are emerging as important components of MLO formation and function. As a result, we name them biocondensates. In this review, we examine the relationships between biocondensates and membrane. First, inhibition of membrane trafficking in the early secretory pathway leads to the formation of biocondensates (P-bodies and Sec bodies). In the same vein, stress granules have a complex relationship with the cyto-nuclear transport machinery. Second, membrane contributes to the regulated formation of phase separation in the cells and we will present examples including clustering at the plasma membrane and at the synapse. Finally, the whole cell appears to transit from an interphase phase-separated state to a mitotic diffuse state in a DYRK3 dependent manner. This firmly establishes a crosstalk between the two types of cell organization that will need to be further explored.
Collapse
Affiliation(s)
- Chujun Zhang
- Hubrecht Institute of the Royal Netherlands Academy of Arts and Sciences, and University Medical Center Utrecht, 3584 CT Utrecht, The Netherlands
| | - Catherine Rabouille
- Hubrecht Institute of the Royal Netherlands Academy of Arts and Sciences, and University Medical Center Utrecht, 3584 CT Utrecht, The Netherlands.
- Department of Biomedical Science of Cells and Systems, University Medical Center Groningen, 9713 AV Groningen, The Netherlands.
| |
Collapse
|
47
|
Abstract
Protein coats are supramolecular complexes that assemble on the cytosolic face of membranes to promote cargo sorting and transport carrier formation in the endomembrane system of eukaryotic cells. Several types of protein coats have been described, including COPI, COPII, AP-1, AP-2, AP-3, AP-4, AP-5, and retromer, which operate at different stages of the endomembrane system. Defects in these coats impair specific transport pathways, compromising the function and viability of the cells. In humans, mutations in subunits of these coats cause various congenital diseases that are collectively referred to as coatopathies. In this article, we review the fundamental properties of protein coats and the diseases that result from mutation of their constituent subunits.
Collapse
Affiliation(s)
- Esteban C Dell'Angelica
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, California 90095, USA
| | - Juan S Bonifacino
- Cell Biology and Neurobiology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health, Bethesda, Maryland 20892, USA;
| |
Collapse
|
48
|
Wang L, Mazagova M, Pan C, Yang S, Brandl K, Liu J, Reilly SM, Wang Y, Miao Z, Loomba R, Lu N, Guo Q, Liu J, Yu RT, Downes M, Evans RM, Brenner DA, Saltiel AR, Beutler B, Schnabl B. YIPF6 controls sorting of FGF21 into COPII vesicles and promotes obesity. Proc Natl Acad Sci U S A 2019; 116:15184-15193. [PMID: 31289229 PMCID: PMC6660779 DOI: 10.1073/pnas.1904360116] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Fibroblast growth factor 21 (FGF21) is an endocrine hormone that regulates glucose, lipid, and energy homeostasis. While gene expression of FGF21 is regulated by the nuclear hormone receptor peroxisome proliferator-activated receptor alpha in the fasted state, little is known about the regulation of trafficking and secretion of FGF21. We show that mice with a mutation in the Yip1 domain family, member 6 gene (Klein-Zschocher [KLZ]; Yipf6KLZ/Y ) on a high-fat diet (HFD) have higher plasma levels of FGF21 than mice that do not carry this mutation (controls) and hepatocytes from Yipf6KLZ/Y mice secrete more FGF21 than hepatocytes from wild-type mice. Consequently, Yipf6KLZ/Y mice are resistant to HFD-induced features of the metabolic syndrome and have increased lipolysis, energy expenditure, and thermogenesis, with an increase in core body temperature. Yipf6KLZ/Y mice with hepatocyte-specific deletion of FGF21 were no longer protected from diet-induced obesity. We show that YIPF6 binds FGF21 in the endoplasmic reticulum to limit its secretion and specifies packaging of FGF21 into coat protein complex II (COPII) vesicles during development of obesity in mice. Levels of YIPF6 protein in human liver correlate with hepatic steatosis and correlate inversely with levels of FGF21 in serum from patients with nonalcoholic fatty liver disease (NAFLD). YIPF6 is therefore a newly identified regulator of FGF21 secretion during development of obesity and could be a target for treatment of obesity and NAFLD.
Collapse
Affiliation(s)
- Lirui Wang
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, 211198 Nanjing, Jiang Su, China;
- Department of Medicine, University of California San Diego, La Jolla, CA 92093
- Department of Medicine, VA San Diego Healthcare System, San Diego, CA 92161
| | - Magdalena Mazagova
- Department of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Chuyue Pan
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, 211198 Nanjing, Jiang Su, China
| | - Song Yang
- Department of Hepatology, Beijing Ditan Hospital, Capital Medical University, Chaoyang District, 100015 Beijing, China
| | - Katharina Brandl
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093
| | - Jun Liu
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, 211198 Nanjing, Jiang Su, China
| | - Shannon M Reilly
- Department of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Yanhan Wang
- Department of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Zhaorui Miao
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, 211198 Nanjing, Jiang Su, China
| | - Rohit Loomba
- Department of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Na Lu
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, 211198 Nanjing, Jiang Su, China
| | - Qinglong Guo
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, 211198 Nanjing, Jiang Su, China
| | - Jihua Liu
- School of Traditional Chinese Pharmacy, China Pharmaceutical University, 211198 Nanjing, Jiang Su, China
| | - Ruth T Yu
- Gene Expression Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037
| | - Michael Downes
- Gene Expression Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037
| | - Ronald M Evans
- Gene Expression Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037
- Howard Hughes Medical Institute, Salk Institute for Biological Studies, La Jolla, CA 92037
| | - David A Brenner
- Department of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Alan R Saltiel
- Department of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Bruce Beutler
- Center for the Genetics of Host Defense, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Bernd Schnabl
- Department of Medicine, University of California San Diego, La Jolla, CA 92093;
- Department of Medicine, VA San Diego Healthcare System, San Diego, CA 92161
| |
Collapse
|
49
|
Wang XT, Cai XY, Xu FX, Zhou L, Zheng R, Ma KY, Xu ZH, Shen Y. MEA6 Deficiency Impairs Cerebellar Development and Motor Performance by Tethering Protein Trafficking. Front Cell Neurosci 2019; 13:250. [PMID: 31244610 PMCID: PMC6580151 DOI: 10.3389/fncel.2019.00250] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 05/20/2019] [Indexed: 11/13/2022] Open
Abstract
Meningioma expressed antigen 6 (MEA6), also called cutaneous T cell lymphoma-associated antigen 5 (cTAGE5), was initially found in tumor tissues. MEA6 is located in endoplasmic reticulum (ER) exit sites and regulates the transport of collagen, very low density lipoprotein, and insulin. It is also reported that MEA6 might be related to Fahr's syndrome, which comprises neurological, movement, and neuropsychiatric disorders. Here, we show that MEA6 is critical to cerebellar development and motor performance. Mice with conditional knockout of MEA6 (Nestin-Cre;MEA6F/F) display smaller sizes of body and brain compared to control animals, and survive maximal 28 days after birth. Immunohistochemical and behavioral studies demonstrate that these mutant mice have defects in cerebellar development and motor performance. In contrast, PC deletion of MEA6 (pCP2-Cre;MEA6F/F) causes milder phenotypes in cerebellar morphology and motor behaviors. While pCP2-Cre;MEA6F/F mice have normal lobular formation and gait, they present the extensive self-crossing of PC dendrites and damaged motor learning. Interestingly, the expression of key molecules that participates in cerebellar development, including Slit2 and brain derived neurotrophic factor (BDNF), is significantly increased in ER, suggesting that MEA6 ablation impairs ER function and thus these proteins are arrested in ER. Our study provides insight into the roles of MEA6 in the brain and the pathogenesis of Fahr's syndrome.
Collapse
Affiliation(s)
- Xin-Tai Wang
- Department of Neurobiology, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Xin-Yu Cai
- Department of Neurobiology, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Fang-Xiao Xu
- Department of Neurobiology, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Lin Zhou
- Department of Neurobiology, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Rui Zheng
- Department of Neurobiology, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Kuang-Yi Ma
- Department of Neurobiology, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Zhi-Heng Xu
- State Key Laboratory of Molecular Developmental Biology, CAS Center for Excellence in Brain Science and Intelligence Technology, Institute of Genetics and Developmental Biology Chinese Academy of Sciences, Beijing, China
| | - Ying Shen
- Department of Neurobiology, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| |
Collapse
|
50
|
Coat flexibility in the secretory pathway: a role in transport of bulky cargoes. Curr Opin Cell Biol 2019; 59:104-111. [PMID: 31125831 PMCID: PMC7116127 DOI: 10.1016/j.ceb.2019.04.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 04/03/2019] [Accepted: 04/09/2019] [Indexed: 01/19/2023]
Abstract
Membrane trafficking in eukaryotic cells is a highly dynamic process, which needs to adapt to a variety of cargo proteins. The COPII coat mediates ER export of thousands of proteins with a wide range of sizes by generating coated membrane vesicles that incapsulate cargo. The process of assembly and disassembly of COPII, regulated by GTP hydrolysis, is a major determinant of the size and shape of transport carriers. Here, we analyse our knowledge of the COPII coat architecture and it assembly/disassembly dynamics, and link coat flexibility to the role of COPII in transport of large cargoes. We propose a common mechanism of action of regulatory factors that modulate COPII GTP hydrolysis cycle to promote budding.
Collapse
|