1
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Zhang X, Yang M, Jiang F, Wang Y, Zhou Z, Wu Z. Targeting CDK1 inhibits Golgi apparatus stress-mediated neuroinflammation and neuronal apoptosis after intracerebral hemorrhage by modulating GRASP55 phosphorylation. Cell Signal 2025; 132:111835. [PMID: 40288664 DOI: 10.1016/j.cellsig.2025.111835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2024] [Revised: 04/06/2025] [Accepted: 04/22/2025] [Indexed: 04/29/2025]
Abstract
Cyclin-dependent kinase 1 (CDK1) has been found to be associated with neuronal apoptosis. However, the role of CDK1 in intracerebral hemorrhage (ICH) remains unclear. The aim of this study was to investigate the role of CDK1 in mediating neuroinflammation and neuronal apoptosis through the modulation of Golgi apparatus stress (GAS) in ICH. In this study, rats received collagenase IV injections to induce ICH, while primary neurons and PC-12 cells were stimulated with Hemin to establish ICH models. We observed that CDK1 expression was upregulated and GAS levels increased after ICH. Downregulation of CDK1 significantly attenuated neuronal damage and GAS levels after ICH. In addition, CDK1 downregulation reduced inflammatory cytokine levels in both in vitro and in vivo models of ICH. Interestingly, the phosphorylation of Golgi reassembly-stacking protein 55 (GRASP55) was significantly increased after ICH. However, CDK1 downregulation was able to reverse this change. Our data show that CDK1 phosphorylates GRASP55 through the T225 site. Lastly, mutating the GRASP55 T225 phosphorylation site abolished the CDK1-mediated exacerbation of GAS, neuronal apoptosis, and inflammatory responses in vitro. In summary, targeted inhibition of CDK1 suppresses GAS-mediated neuroinflammation and neuronal apoptosis after ICH by regulating GRASP55 phosphorylation. Research on CDK1 may offer clinicians new insights into the treatment of patients with ICH.
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Affiliation(s)
- Xiaobo Zhang
- Department of Neurology, Changde Hospital, Xiangya School of Medicine, Central South University, Changde 415000, China
| | - Ming Yang
- Department of Neurology, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, Quzhou 324002, China
| | - Feifei Jiang
- Department of Neurology, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, Quzhou 324002, China
| | - Yu Wang
- Department of Neurology, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, Quzhou 324002, China
| | - Zheng Zhou
- Department of Hematology, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, Quzhou 324002, China
| | - Zhaoping Wu
- Department of Neurology, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, Quzhou 324002, China.
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2
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Calvo-Jiménez E, Stam K, Jossi A, Jossin Y. GRASPs link Reelin to the Golgi during neocortical development to control neuronal migration and dendritogenesis. Commun Biol 2025; 8:572. [PMID: 40188221 PMCID: PMC11972360 DOI: 10.1038/s42003-025-08014-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Accepted: 03/28/2025] [Indexed: 04/07/2025] Open
Abstract
Reelin serves as a crucial regulator of brain organogenesis, playing a significant role in neuronal positioning and dendritogenesis. At subcellular level, it influences the translocation and remodeling of the Golgi apparatus. Despite its importance, the mechanisms by which Reelin governs the Golgi during neuronal migration and dendrite formation remain largely unknown. This study reveals that Reelin promotes de novo translation of Golgi Re-Assembly Stacking Proteins (GRASPs), which are essential for the functions of Reelin on cortical neurons. Downregulation of GRASPs in migrating excitatory neurons of the embryonic neocortex leads to disoriented cells during the multipolar phase of migration and an aberrant leading process length during locomotion. Postnatally, it results in mislocalized neurons displaying a disorganized Golgi structure and an improperly oriented, underdeveloped apical dendrite. Our findings position GRASPs and their role in Golgi morphology modulation as novel contributors to the Reelin-mediated processes during embryonic development of the mammalian neocortex.
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Affiliation(s)
- Elisa Calvo-Jiménez
- Laboratory of Mammalian Development & Cell Biology, Institute of Neuroscience, Université Catholique de Louvain, Brussels, Belgium
| | - Kirsten Stam
- Laboratory of Mammalian Development & Cell Biology, Institute of Neuroscience, Université Catholique de Louvain, Brussels, Belgium
| | - Angélique Jossi
- Laboratory of Mammalian Development & Cell Biology, Institute of Neuroscience, Université Catholique de Louvain, Brussels, Belgium
| | - Yves Jossin
- Laboratory of Mammalian Development & Cell Biology, Institute of Neuroscience, Université Catholique de Louvain, Brussels, Belgium.
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3
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Lin L. Unconventional protein secretion: Exploring membrane proteins and beyond. Curr Opin Cell Biol 2025; 93:102469. [PMID: 39903992 DOI: 10.1016/j.ceb.2025.102469] [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: 11/29/2024] [Revised: 01/16/2025] [Accepted: 01/16/2025] [Indexed: 02/06/2025]
Abstract
Protein secretion is essential for cellular communication and function, enabling the delivery of both soluble and integral membrane proteins to the extracellular space and the cell surface. While the classical endoplasmic reticulum (ER)-Golgi pathway has been extensively studied, emerging evidence highlights the existence of unconventional protein secretion (UcPS) pathways. Among these, the mechanisms that enable membrane proteins to bypass the Golgi apparatus remain poorly understood. In this review, I discuss recent advances that shed light on the processes governing Golgi-bypassing membrane secretion. These findings reveal that UcPS of membrane proteins is evolutionarily conserved, operates under both physiological and stress conditions, and involves diverse intermediate carriers and molecular players. Looking ahead, advances in technology and the development of more sophisticated functional assays, along with in vivo models, are expected to further unravel the molecular mechanisms and biological roles of these unconventional pathways.
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Affiliation(s)
- Long Lin
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China.
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4
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Liu Y, Zhang H, Li X, He T, Zhang W, Ji C, Wang J. Molecular mechanisms and pathological implications of unconventional protein secretion in human disease: from cellular stress to therapeutic targeting. Mol Biol Rep 2025; 52:236. [PMID: 39955475 DOI: 10.1007/s11033-025-10316-6] [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: 12/04/2024] [Accepted: 01/28/2025] [Indexed: 02/17/2025]
Abstract
Unconventional protein secretion (UcPS) encompasses diverse non-canonical cellular export mechanisms that operate independently of the classical secretory pathway, representing a crucial cellular response to various physiological and pathological conditions. This comprehensive review synthesizes current understanding of UcPS mechanisms, particularly focusing on their roles in disease pathogenesis and progression. Recent advances in proteomics and cellular biology have revealed that UcPS facilitates the secretion of various biomedically significant proteins, including inflammatory mediators, growth factors, and disease-associated proteins, through multiple pathways such as membrane translocation, secretory lysosomes, and membrane-bound organelles. Notably, dysregulation of UcPS mechanisms has been implicated in various pathological conditions, including chronic inflammation, neurodegenerative disorders, and malignant transformation. We critically evaluate the molecular machinery governing UcPS, its regulation under cellular stress, and its contribution to disease mechanisms. Furthermore, we examine emerging therapeutic strategies targeting UcPS pathways, highlighting both opportunities and challenges in developing novel interventional approaches.
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Affiliation(s)
- Yukun Liu
- College of Chemistry and Life Science, Beijing University of Technology, 100 Pingleyuan, Chaoyang District, Beijing, 100124, China
| | - Haolin Zhang
- College of Chemistry and Life Science, Beijing University of Technology, 100 Pingleyuan, Chaoyang District, Beijing, 100124, China
| | - Xianghua Li
- College of Chemistry and Life Science, Beijing University of Technology, 100 Pingleyuan, Chaoyang District, Beijing, 100124, China
| | - Tianlong He
- College of Chemistry and Life Science, Beijing University of Technology, 100 Pingleyuan, Chaoyang District, Beijing, 100124, China
| | - Wenting Zhang
- College of Chemistry and Life Science, Beijing University of Technology, 100 Pingleyuan, Chaoyang District, Beijing, 100124, China
| | - Cuicui Ji
- College of Chemistry and Life Science, Beijing University of Technology, 100 Pingleyuan, Chaoyang District, Beijing, 100124, China.
| | - Juan Wang
- College of Chemistry and Life Science, Beijing University of Technology, 100 Pingleyuan, Chaoyang District, Beijing, 100124, China.
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5
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Da Silva K, Kumar P, Choonara YE. The paradigm of stem cell secretome in tissue repair and regeneration: Present and future perspectives. Wound Repair Regen 2025; 33:e13251. [PMID: 39780313 PMCID: PMC11711308 DOI: 10.1111/wrr.13251] [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: 08/01/2024] [Revised: 12/04/2024] [Accepted: 12/13/2024] [Indexed: 01/11/2025]
Abstract
As the number of patients requiring organ transplants continues to rise exponentially, there is a dire need for therapeutics, with repair and regenerative properties, to assist in alleviating this medical crisis. Over the past decade, there has been a shift from conventional stem cell treatments towards the use of the secretome, the protein and factor secretions from cells. These components may possess novel druggable targets and hold the key to profoundly altering the field of regenerative medicine. Despite the progress in this field, clinical translation of secretome-containing products is limited by several challenges including but not limited to ensuring batch-to-batch consistency, the prevention of further heterogeneity, production of sufficient secretome quantities, product registration, good manufacturing practice protocols and the pharmacokinetic/pharmacodynamic profiles of all the components. Despite this, the secretome may hold the key to unlocking the regenerative blockage scientists have encountered for years. This review critically analyses the secretome derived from different cell sources and used in several tissues for tissue regeneration. Furthermore, it provides an overview of the current delivery strategies and the future perspectives for the secretome as a potential therapeutic. The success and possible shortcomings of the secretome are evaluated.
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Affiliation(s)
- Kate Da Silva
- Wits Advanced Drug Delivery Platform (WADDP) Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health SciencesUniversity of the WitwatersrandJohannesburgSouth Africa
| | - Pradeep Kumar
- Wits Advanced Drug Delivery Platform (WADDP) Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health SciencesUniversity of the WitwatersrandJohannesburgSouth Africa
| | - Yahya E. Choonara
- Wits Advanced Drug Delivery Platform (WADDP) Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health SciencesUniversity of the WitwatersrandJohannesburgSouth Africa
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6
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Greig J, Bates GT, Yin DI, Briant K, Simonetti B, Cullen PJ, Brodsky FM. CHC22 clathrin recruitment to the early secretory pathway requires two-site interaction with SNX5 and p115. EMBO J 2024; 43:4298-4323. [PMID: 39160272 PMCID: PMC11445476 DOI: 10.1038/s44318-024-00198-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 07/15/2024] [Accepted: 07/17/2024] [Indexed: 08/21/2024] Open
Abstract
The two clathrin isoforms, CHC17 and CHC22, mediate separate intracellular transport routes. CHC17 performs endocytosis and housekeeping membrane traffic in all cells. CHC22, expressed most highly in skeletal muscle, shuttles the glucose transporter GLUT4 from the ERGIC (endoplasmic-reticulum-to-Golgi intermediate compartment) directly to an intracellular GLUT4 storage compartment (GSC), from where GLUT4 can be mobilized to the plasma membrane by insulin. Here, molecular determinants distinguishing CHC22 from CHC17 trafficking are defined. We show that the C-terminal trimerization domain of CHC22 interacts with SNX5, which also binds the ERGIC tether p115. SNX5, and the functionally redundant SNX6, are required for CHC22 localization independently of their participation in the endosomal ESCPE-1 complex. In tandem, an isoform-specific patch in the CHC22 N-terminal domain separately mediates binding to p115. This dual mode of clathrin recruitment, involving interactions at both N- and C-termini of the heavy chain, is required for CHC22 targeting to ERGIC membranes to mediate the Golgi-bypass route for GLUT4 trafficking. Interference with either interaction inhibits GLUT4 targeting to the GSC, defining a bipartite mechanism regulating a key pathway in human glucose metabolism.
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Affiliation(s)
- Joshua Greig
- Structural and Molecular Biology, Division of Biosciences, University College London, London, WC1E 6BT, UK
- Institute of Structural and Molecular Biology, Birkbeck and University College London, London, WC1E 7HX, UK
| | - George T Bates
- Structural and Molecular Biology, Division of Biosciences, University College London, London, WC1E 6BT, UK
- Institute of Structural and Molecular Biology, Birkbeck and University College London, London, WC1E 7HX, UK
| | - Daowen I Yin
- Structural and Molecular Biology, Division of Biosciences, University College London, London, WC1E 6BT, UK
- Institute of Structural and Molecular Biology, Birkbeck and University College London, London, WC1E 7HX, UK
| | - Kit Briant
- Structural and Molecular Biology, Division of Biosciences, University College London, London, WC1E 6BT, UK
- Institute of Structural and Molecular Biology, Birkbeck and University College London, London, WC1E 7HX, UK
| | - Boris Simonetti
- School of Biochemistry, Faculty of Life Sciences, University of Bristol, Bristol, UK
| | - Peter J Cullen
- School of Biochemistry, Faculty of Life Sciences, University of Bristol, Bristol, UK
| | - Frances M Brodsky
- Structural and Molecular Biology, Division of Biosciences, University College London, London, WC1E 6BT, UK.
- Institute of Structural and Molecular Biology, Birkbeck and University College London, London, WC1E 7HX, UK.
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7
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Kumar K, Basak R, Rai A, Mukhopadhyay A. GRASP negatively regulates the secretion of the virulence factor gp63 in Leishmania. Mol Microbiol 2024; 121:1063-1078. [PMID: 38558112 DOI: 10.1111/mmi.15255] [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: 07/26/2023] [Revised: 03/12/2024] [Accepted: 03/14/2024] [Indexed: 04/04/2024]
Abstract
Metalloprotease-gp63 is a virulence factor secreted by Leishmania. However, secretory pathway in Leishmania is not well defined. Here, we cloned and expressed the GRASP homolog from Leishmania. We found that Leishmania expresses one GRASP homolog of 58 kDa protein (LdGRASP) which localizes in LdRab1- and LPG2-positive Golgi compartment in Leishmania. LdGRASP was found to bind with COPII complex, LdARF1, LdRab1 and LdRab11 indicating its role in ER and Golgi transport in Leishmania. To determine the function of LdGRASP, we generated LdGRASP knockout parasites using CRISPR-Cas9. We found fragmentation of Golgi in Ld:GRASPKO parasites. Our results showed enhanced transport of non-GPI-anchored gp63 to the cell surface leading to higher secretion of this form of gp63 in Ld:GRASPKO parasites in comparison to Ld:WT cells. In contrast, we found that transport of GPI-anchored gp63 to the cell surface is blocked in Ld:GRASPKO parasites and thereby inhibits its secretion. The overexpression of dominant-negative mutant of LdRab1 or LdSar1 in Ld:GRASPKO parasites significantly blocked the secretion of non-GPI-anchored gp63. Interestingly, we found that survival of transgenic parasites overexpressing Ld:GRASP-GFP is significantly compromised in macrophages in comparison to Ld:WT and Ld:GRASPKO parasites. These results demonstrated that LdGRASP differentially regulates Ldgp63 secretory pathway in Leishmania.
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Affiliation(s)
- Kamal Kumar
- Kusuma School of Biological Sciences, Indian Institute of Technology, New Delhi, India
| | - Rituparna Basak
- Kusuma School of Biological Sciences, Indian Institute of Technology, New Delhi, India
| | - Aakansha Rai
- Kusuma School of Biological Sciences, Indian Institute of Technology, New Delhi, India
| | - Amitabha Mukhopadhyay
- Kusuma School of Biological Sciences, Indian Institute of Technology, New Delhi, India
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8
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Li X, Liu B, Wen Y, Wang J, Guo YR, Shi A, Lin L. Coordination of RAB-8 and RAB-11 during unconventional protein secretion. J Cell Biol 2024; 223:e202306107. [PMID: 38019180 PMCID: PMC10686230 DOI: 10.1083/jcb.202306107] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 10/17/2023] [Accepted: 11/16/2023] [Indexed: 11/30/2023] Open
Abstract
Multiple physiology-pertinent transmembrane proteins reach the cell surface via the Golgi-bypassing unconventional protein secretion (UcPS) pathway. By employing C. elegans-polarized intestine epithelia, we recently have revealed that the small GTPase RAB-8/Rab8 serves as an important player in the process. Nonetheless, its function and the relevant UcPS itinerary remain poorly understood. Here, we show that deregulated RAB-8 activity resulted in impaired apical UcPS, which increased sensitivity to infection and environmental stress. We also identified the SNARE VTI-1/Vti1a/b as a new RAB-8-interacting factor involved in the apical UcPS. Besides, RAB-11/Rab11 was capable of recruiting RABI-8/Rabin8 to reduce the guanine nucleotide exchange activity of SMGL-1/GEF toward RAB-8, indicating the necessity of a finely tuned RAB-8/RAB-11 network. Populations of RAB-8- and RAB-11-positive endosomal structures containing the apical UcPS cargo moved toward the apical side. In the absence of RAB-11 or its effectors, the cargo was retained in RAB-8- and RAB-11-positive endosomes, respectively, suggesting that these endosomes are utilized as intermediate carriers for the UcPS.
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Affiliation(s)
- Xinxin Li
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Bowen Liu
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yue Wen
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jiabin Wang
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yusong R. Guo
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Anbing Shi
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Long Lin
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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9
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Pang A, Wang H, Luo Y, Zhang F, Wu F, Zhou Z, Lu Z, Lin F. Investigating the cellular functions of β-Glucosidases for synthesis of lignocellulose-degrading enzymes in Trichoderma reesei. ENGINEERING MICROBIOLOGY 2023; 3:100105. [PMID: 39628917 PMCID: PMC11610954 DOI: 10.1016/j.engmic.2023.100105] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 07/03/2023] [Accepted: 07/03/2023] [Indexed: 12/06/2024]
Abstract
β-glucosidases play an important role in the synthesis of cellulase in fungi, but their molecular functions and mechanisms remain unknown. We found that the 10 putative β-glucosidases investigated in Trichoderma reesei facilitate cellulase production, with cel3j being the most crucial. Transcriptional analysis revealed that the most affected biological processes in △cel3j strain were cellulase synthesis, ribosome biogenesis, and RNA polymerases. Moreover, CEL3J was unconventionally transported through the endoplasmic reticulum, bypassing the Golgi apparatus, whereas cel3j overexpression altered cellulase secretion from conventional to unconventional, likely owing to the activated unconventional protein secretion pathway (UPS), as indicated by the upregulation of genes related to UPS. The mTORC1-GRASP55 signaling axis may modulate the unconventional secretion of CEL3J and cellulase. The transcriptional levels of genes associated with DNA replication, the cell cycle, and meiosis were noticeably affected by overexpressing cel3j. These data give new clues for exploring the roles of β-glucosidases and the molecular mechanisms of their unconventional secretion in fungi.
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Affiliation(s)
- Ai–Ping Pang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Haiyan Wang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Yongsheng Luo
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Funing Zhang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Fu–Gen Wu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Zhihua Zhou
- Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Zuhong Lu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Fengming Lin
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
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10
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Shaping subcellular tubes through vesicle trafficking: Common and distinct pathways. Semin Cell Dev Biol 2023; 133:74-82. [PMID: 35365398 DOI: 10.1016/j.semcdb.2022.03.024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 03/18/2022] [Accepted: 03/20/2022] [Indexed: 11/23/2022]
Abstract
Cells with subcellular lumens form some of the most miniature tubes in the tubular organs of animals. These are often crucial components of the system, executing functions at remote body locations. Unlike tubes formed by intercellular or autocellular junctions, the cells with junctionless subcellular lumens face unique challenges in modifying the cell shape and plasma membrane organization to incorporate a membrane-bound tube within, often associated with dramatic cellular growth and extensions. Results in the recent years have shown that membrane dynamics, including both the primary delivery and recycling, is crucial in providing the cell with the flexibility to face these challenges. A significant portion of this information has come from two in vivo invertebrate models; the Drosophila tracheal terminal cells and the C. elegans excretory cell. This review focuses on the data obtained from these systems in the recent past about how trafficking pathways influence subcellular tube and branching morphogenesis. Given that such tubes occur in vertebrate vasculature, these insights are relevant to human health, and we contrast our conclusions with the less understood subcellular tubes of angiogenesis.
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11
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Subcellular spatial transcriptomics identifies three mechanistically different classes of localizing RNAs. Nat Commun 2022; 13:6355. [PMID: 36289223 PMCID: PMC9606379 DOI: 10.1038/s41467-022-34004-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 10/03/2022] [Indexed: 12/25/2022] Open
Abstract
Intracellular RNA localization is a widespread and dynamic phenomenon that compartmentalizes gene expression and contributes to the functional polarization of cells. Thus far, mechanisms of RNA localization identified in Drosophila have been based on a few RNAs in different tissues, and a comprehensive mechanistic analysis of RNA localization in a single tissue is lacking. Here, by subcellular spatial transcriptomics we identify RNAs localized in the apical and basal domains of the columnar follicular epithelium (FE) and we analyze the mechanisms mediating their localization. Whereas the dynein/BicD/Egl machinery controls apical RNA localization, basally-targeted RNAs require kinesin-1 to overcome a default dynein-mediated transport. Moreover, a non-canonical, translation- and dynein-dependent mechanism mediates apical localization of a subgroup of dynein-activating adaptor-encoding RNAs (BicD, Bsg25D, hook). Altogether, our study identifies at least three mechanisms underlying RNA localization in the FE, and suggests a possible link between RNA localization and dynein/dynactin/adaptor complex formation in vivo.
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12
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Kuo IY, Hsieh CH, Kuo WT, Chang CP, Wang YC. Recent advances in conventional and unconventional vesicular secretion pathways in the tumor microenvironment. J Biomed Sci 2022; 29:56. [PMID: 35927755 PMCID: PMC9354273 DOI: 10.1186/s12929-022-00837-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Accepted: 07/18/2022] [Indexed: 11/18/2022] Open
Abstract
All cells in the changing tumor microenvironment (TME) need a class of checkpoints to regulate the balance among exocytosis, endocytosis, recycling and degradation. The vesicular trafficking and secretion pathways regulated by the small Rab GTPases and their effectors convey cell growth and migration signals and function as meditators of intercellular communication and molecular transfer. Recent advances suggest that Rab proteins govern conventional and unconventional vesicular secretion pathways by trafficking widely diverse cargoes and substrates in remodeling TME. The mechanisms underlying the regulation of conventional and unconventional vesicular secretion pathways, their action modes and impacts on the cancer and stromal cells have been the focus of much attention for the past two decades. In this review, we discuss the current understanding of vesicular secretion pathways in TME. We begin with an overview of the structure, regulation, substrate recognition and subcellular localization of vesicular secretion pathways. We then systematically discuss how the three fundamental vesicular secretion processes respond to extracellular cues in TME. These processes are the conventional protein secretion via the endoplasmic reticulum-Golgi apparatus route and two types of unconventional protein secretion via extracellular vesicles and secretory autophagy. The latest advances and future directions in vesicular secretion-involved interplays between tumor cells, stromal cell and host immunity are also described.
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Affiliation(s)
- I-Ying Kuo
- Department of Pharmacology, College of Medicine, National Cheng Kung University, No.1, University Road, Tainan, 701, Taiwan.,Department of Biotechnology, College of Life Science, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chih-Hsiung Hsieh
- Department of Pharmacology, College of Medicine, National Cheng Kung University, No.1, University Road, Tainan, 701, Taiwan
| | - Wan-Ting Kuo
- Department of Pharmacology, College of Medicine, National Cheng Kung University, No.1, University Road, Tainan, 701, Taiwan.,Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, No.1, University Road, Tainan, 701, Taiwan
| | - Chih-Peng Chang
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, No.1, University Road, Tainan, 701, Taiwan. .,Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
| | - Yi-Ching Wang
- Department of Pharmacology, College of Medicine, National Cheng Kung University, No.1, University Road, Tainan, 701, Taiwan. .,Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
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13
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Park H, Seo SK, Sim J, Hwang SJ, Kim YJ, Shin DH, Jang DG, Noh SH, Park P, Ko SH, Shin MH, Choi JY, Ito Y, Kang C, Lee JM, Lee MG. TMED3 Complex Mediates ER Stress-Associated Secretion of CFTR, Pendrin, and SARS-CoV-2 Spike. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2105320. [PMID: 35748162 PMCID: PMC9350134 DOI: 10.1002/advs.202105320] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 05/06/2022] [Indexed: 05/13/2023]
Abstract
Under ER stress conditions, the ER form of transmembrane proteins can reach the plasma membrane via a Golgi-independent unconventional protein secretion (UPS) pathway. However, the targeting mechanisms of membrane proteins for UPS are unknown. Here, this study reports that TMED proteins play a critical role in the ER stress-associated UPS of transmembrane proteins. The gene silencing results reveal that TMED2, TMED3, TMED9 and TMED10 are involved in the UPS of transmembrane proteins, such as CFTR, pendrin and SARS-CoV-2 Spike. Subsequent mechanistic analyses indicate that TMED3 recognizes the ER core-glycosylated protein cargos and that the heteromeric TMED2/3/9/10 complex mediates their UPS. Co-expression of all four TMEDs improves, while each single expression reduces, the UPS and ion transport function of trafficking-deficient ΔF508-CFTR and p.H723R-pendrin, which cause cystic fibrosis and Pendred syndrome, respectively. In contrast, TMED2/3/9/10 silencing reduces SARS-CoV-2 viral release. These results provide evidence for a common role of TMED3 and related TMEDs in the ER stress-associated, Golgi-independent secretion of transmembrane proteins.
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Affiliation(s)
- Hak Park
- Department of PharmacologySeverance Biomedical Science InstituteYonsei University College of MedicineSeoul03722Korea
- Department of Laboratory MedicineSeverance HospitalYonsei University College of MedicineSeoul03722Korea
| | - Soo Kyung Seo
- Department of PharmacologySeverance Biomedical Science InstituteYonsei University College of MedicineSeoul03722Korea
- Graduate School of Medical ScienceBrain Korea 21 ProjectYonsei University College of MedicineSeoul03722Korea
| | - Ju‐Ri Sim
- Department of PharmacologySeverance Biomedical Science InstituteYonsei University College of MedicineSeoul03722Korea
- Graduate School of Medical ScienceBrain Korea 21 ProjectYonsei University College of MedicineSeoul03722Korea
| | - Su Jin Hwang
- Graduate School of Medical ScienceBrain Korea 21 ProjectYonsei University College of MedicineSeoul03722Korea
- Department of Microbiology and ImmunologyInstitute for Immunology and Immunological DiseasesYonsei University College of MedicineSeoul03722Korea
| | - Ye Jin Kim
- Department of PharmacologySeverance Biomedical Science InstituteYonsei University College of MedicineSeoul03722Korea
- Graduate School of Medical ScienceBrain Korea 21 ProjectYonsei University College of MedicineSeoul03722Korea
| | - Dong Hoon Shin
- Department of PharmacologySeverance Biomedical Science InstituteYonsei University College of MedicineSeoul03722Korea
| | - Dong Geon Jang
- Department of PharmacologySeverance Biomedical Science InstituteYonsei University College of MedicineSeoul03722Korea
- Graduate School of Medical ScienceBrain Korea 21 ProjectYonsei University College of MedicineSeoul03722Korea
| | - Shin Hye Noh
- Department of PharmacologySeverance Biomedical Science InstituteYonsei University College of MedicineSeoul03722Korea
| | - Pil‐Gu Park
- Department of Microbiology and ImmunologyInstitute for Immunology and Immunological DiseasesYonsei University College of MedicineSeoul03722Korea
| | - Si Hwan Ko
- Department of Microbiology and ImmunologyInstitute for Immunology and Immunological DiseasesYonsei University College of MedicineSeoul03722Korea
| | - Mi Hwa Shin
- Department of OtorhinolaryngologyYonsei University College of MedicineSeoul03722Korea
| | - Jae Young Choi
- Department of OtorhinolaryngologyYonsei University College of MedicineSeoul03722Korea
| | - Yukishige Ito
- Cluster for Pioneering ResearchRIKENWakoSaitama351‐0198Japan
- Graduate School of ScienceOsaka UniversityToyonakaOsaka560‐0043Japan
| | - Chung‐Min Kang
- Department of Pediatric DentistryCollege of DentistryYonsei UniversitySeoul03722Korea
| | - Jae Myun Lee
- Graduate School of Medical ScienceBrain Korea 21 ProjectYonsei University College of MedicineSeoul03722Korea
- Department of Microbiology and ImmunologyInstitute for Immunology and Immunological DiseasesYonsei University College of MedicineSeoul03722Korea
| | - Min Goo Lee
- Department of PharmacologySeverance Biomedical Science InstituteYonsei University College of MedicineSeoul03722Korea
- Graduate School of Medical ScienceBrain Korea 21 ProjectYonsei University College of MedicineSeoul03722Korea
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14
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Ahat E, Bui S, Zhang J, da Veiga Leprevost F, Sharkey L, Reid W, Nesvizhskii AI, Paulson HL, Wang Y. GRASP55 regulates the unconventional secretion and aggregation of mutant huntingtin. J Biol Chem 2022; 298:102219. [PMID: 35780830 PMCID: PMC9352920 DOI: 10.1016/j.jbc.2022.102219] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Revised: 06/19/2022] [Accepted: 06/20/2022] [Indexed: 11/25/2022] Open
Abstract
Recent studies demonstrated that the Golgi reassembly stacking proteins (GRASPs), especially GRASP55, regulate Golgi-independent unconventional secretion of certain cytosolic and transmembrane cargoes; however, the underlying mechanism remains unknown. Here, we surveyed several neurodegenerative disease-related proteins, including mutant huntingtin (Htt-Q74), superoxide dismutase 1 (SOD1), tau, and TAR DNA-binding protein 43 (TDP-43), for unconventional secretion; our results show that Htt-Q74 is most robustly secreted in a GRASP55-dependent manner. Using Htt-Q74 as a model system, we demonstrate that unconventional secretion of Htt is GRASP55 and autophagy dependent and is enhanced under stress conditions such as starvation and endoplasmic reticulum stress. Mechanistically, we show that GRASP55 facilitates Htt secretion by tethering autophagosomes to lysosomes to promote autophagosome maturation and subsequent lysosome secretion and by stabilizing p23/TMED10, a channel for translocation of cytoplasmic proteins into the lumen of the endoplasmic reticulum-Golgi intermediate compartment. Moreover, we found that GRASP55 levels are upregulated by various stresses to facilitate unconventional secretion, whereas inhibition of Htt-Q74 secretion by GRASP55 KO enhances Htt aggregation and toxicity. Finally, comprehensive secretomic analysis identified novel cytosolic cargoes secreted by the same unconventional pathway, including transgelin (TAGLN), multifunctional protein ADE2 (PAICS), and peroxiredoxin-1 (PRDX1). In conclusion, this study defines the pathway of GRASP55-mediated unconventional protein secretion and provides important insights into the progression of Huntington's disease.
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Affiliation(s)
- Erpan Ahat
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Sarah Bui
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Jianchao Zhang
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
| | | | - Lisa Sharkey
- Department of Neurology, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Whitney Reid
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Alexey I. Nesvizhskii
- Department of Pathology, University of Michigan School of Medicine, Ann Arbor, Michigan, USA,Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan, USA
| | - Henry L. Paulson
- Department of Neurology, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Yanzhuang Wang
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA; Department of Neurology, University of Michigan School of Medicine, Ann Arbor, Michigan, USA.
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15
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Iglesia RP, Prado MB, Alves RN, Escobar MIM, Fernandes CFDL, Fortes ACDS, Souza MCDS, Boccacino JM, Cangiano G, Soares SR, de Araújo JPA, Tiek DM, Goenka A, Song X, Keady JR, Hu B, Cheng SY, Lopes MH. Unconventional Protein Secretion in Brain Tumors Biology: Enlightening the Mechanisms for Tumor Survival and Progression. Front Cell Dev Biol 2022; 10:907423. [PMID: 35784465 PMCID: PMC9242006 DOI: 10.3389/fcell.2022.907423] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 05/26/2022] [Indexed: 11/28/2022] Open
Abstract
Non-canonical secretion pathways, collectively known as unconventional protein secretion (UPS), are alternative secretory mechanisms usually associated with stress-inducing conditions. UPS allows proteins that lack a signal peptide to be secreted, avoiding the conventional endoplasmic reticulum-Golgi complex secretory pathway. Molecules that generally rely on the canonical pathway to be secreted may also use the Golgi bypass, one of the unconventional routes, to reach the extracellular space. UPS studies have been increasingly growing in the literature, including its implication in the biology of several diseases. Intercellular communication between brain tumor cells and the tumor microenvironment is orchestrated by various molecules, including canonical and non-canonical secreted proteins that modulate tumor growth, proliferation, and invasion. Adult brain tumors such as gliomas, which are aggressive and fatal cancers with a dismal prognosis, could exploit UPS mechanisms to communicate with their microenvironment. Herein, we provide functional insights into the UPS machinery in the context of tumor biology, with a particular focus on the secreted proteins by alternative routes as key regulators in the maintenance of brain tumors.
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Affiliation(s)
- Rebeca Piatniczka Iglesia
- Laboratory of Neurobiology and Stem Cells, Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil,The Robert H. Lurie Comprehensive Cancer Center, The Ken and Ruth Davee Department of Neurology, Lou and Jean Malnati Brain Tumor Institute at Northwestern Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Mariana Brandão Prado
- Laboratory of Neurobiology and Stem Cells, Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Rodrigo Nunes Alves
- Laboratory of Neurobiology and Stem Cells, Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Maria Isabel Melo Escobar
- Laboratory of Neurobiology and Stem Cells, Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Camila Felix de Lima Fernandes
- Laboratory of Neurobiology and Stem Cells, Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Ailine Cibele dos Santos Fortes
- Laboratory of Neurobiology and Stem Cells, Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Maria Clara da Silva Souza
- Laboratory of Neurobiology and Stem Cells, Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Jacqueline Marcia Boccacino
- Laboratory of Neurobiology and Stem Cells, Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Giovanni Cangiano
- Laboratory of Neurobiology and Stem Cells, Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Samuel Ribeiro Soares
- Laboratory of Neurobiology and Stem Cells, Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - João Pedro Alves de Araújo
- Laboratory of Neurobiology and Stem Cells, Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Deanna Marie Tiek
- The Robert H. Lurie Comprehensive Cancer Center, The Ken and Ruth Davee Department of Neurology, Lou and Jean Malnati Brain Tumor Institute at Northwestern Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Anshika Goenka
- The Robert H. Lurie Comprehensive Cancer Center, The Ken and Ruth Davee Department of Neurology, Lou and Jean Malnati Brain Tumor Institute at Northwestern Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Xiao Song
- The Robert H. Lurie Comprehensive Cancer Center, The Ken and Ruth Davee Department of Neurology, Lou and Jean Malnati Brain Tumor Institute at Northwestern Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Jack Ryan Keady
- The Robert H. Lurie Comprehensive Cancer Center, The Ken and Ruth Davee Department of Neurology, Lou and Jean Malnati Brain Tumor Institute at Northwestern Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Bo Hu
- The Robert H. Lurie Comprehensive Cancer Center, The Ken and Ruth Davee Department of Neurology, Lou and Jean Malnati Brain Tumor Institute at Northwestern Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Shi Yuan Cheng
- The Robert H. Lurie Comprehensive Cancer Center, The Ken and Ruth Davee Department of Neurology, Lou and Jean Malnati Brain Tumor Institute at Northwestern Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Marilene Hohmuth Lopes
- Laboratory of Neurobiology and Stem Cells, Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil,*Correspondence: Marilene Hohmuth Lopes,
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16
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Noh SH, Kim YJ, Lee MG. Autophagy-Related Pathways in Vesicular Unconventional Protein Secretion. Front Cell Dev Biol 2022; 10:892450. [PMID: 35774225 PMCID: PMC9237382 DOI: 10.3389/fcell.2022.892450] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 05/26/2022] [Indexed: 12/14/2022] Open
Abstract
Cellular proteins directed to the plasma membrane or released into the extracellular space can undergo a number of different pathways. Whereas the molecular mechanisms that underlie conventional ER-to-Golgi trafficking are well established, those associated with the unconventional protein secretion (UPS) pathways remain largely elusive. A pathway with an emerging role in UPS is autophagy. Although originally known as a degradative process for maintaining intracellular homeostasis, recent studies suggest that autophagy has diverse biological roles besides its disposal function and that it is mechanistically involved in the UPS of various secretory cargos including both leaderless soluble and Golgi-bypassing transmembrane proteins. Here, we summarize current knowledge of the autophagy-related UPS pathways, describing and comparing diverse features in the autophagy-related UPS cargos and autophagy machineries utilized in UPS. Additionally, we also suggest potential directions that further research in this field can take.
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Affiliation(s)
- Shin Hye Noh
- Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, South Korea
| | - Ye Jin Kim
- Department of Pharmacology, Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea
| | - Min Goo Lee
- Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, South Korea
- Department of Pharmacology, Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea
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17
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Wang X, Li X, Wang J, Wang J, Hu C, Zeng J, Shi A, Lin L. SMGL-1/NBAS acts as a RAB-8 GEF to regulate unconventional protein secretion. J Cell Biol 2022; 221:213235. [PMID: 35604368 PMCID: PMC9129922 DOI: 10.1083/jcb.202111125] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 04/13/2022] [Accepted: 05/04/2022] [Indexed: 01/07/2023] Open
Abstract
Unconventional protein secretion (UPS) pathways are conserved across species. However, the underlying mechanisms that regulate Golgi-bypassing UPS of integral proteins remain elusive. In this study, we show that RAB-8 and SMGL-1/NBAS are required for the UPS of integral proteins in C. elegans intestine. SMGL-1 resides in the ER-Golgi intermediate compartment and adjacent RAB-8-positive structures, and NRZ complex component CZW-1/ZW10 is required for this residency. Notably, SMGL-1 acts as a guanine nucleotide exchange factor for RAB-8, ensuring UPS of integral proteins by driving the activation of RAB-8. Furthermore, we show that Pseudomonas aeruginosa infection elevated the expression of SMGL-1 and RAB-8. Loss of SMGL-1 or RAB-8 compromised resistance to environmental colchicine, arsenite, and pathogenic bacteria. These results suggest that the SMGL-1/RAB-8-mediated UPS could integrate environmental signals to serve as a host defense response. Together, by establishing the C. elegans intestine as a multicellular model, our findings provide insights into RAB-8-dependent Golgi-bypassing UPS, especially in the context of epithelia in vivo.
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Affiliation(s)
- Xianghong Wang
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xinxin Li
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Junkai Wang
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Jiabin Wang
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Can Hu
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Jia Zeng
- Department of Biochemistry and Molecular Biology, Guizhou Medical University, Guiyang, Guizhou, China
| | - Anbing Shi
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China,Cell Architecture Research Center, Huazhong University of Science and Technology, Wuhan, Hubei, China,Correspondence to Anbing Shi:
| | - Long Lin
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China,Cell Architecture Research Center, Huazhong University of Science and Technology, Wuhan, Hubei, China,Long Lin:
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18
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Biswal MR, Padmanabhan S, Manjithaya R, Prakash MK. Early Bioinformatic Implication of Triacidic Amino Acid Motifs in Autophagy-Dependent Unconventional Secretion of Mammalian Proteins. Front Cell Dev Biol 2022; 10:863825. [PMID: 35646924 PMCID: PMC9136135 DOI: 10.3389/fcell.2022.863825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 04/11/2022] [Indexed: 11/22/2022] Open
Abstract
Several proteins are secreted outside the cell, and in many cases, they may be identified by a characteristic signal peptide. However, more and more studies point to the evidence for an “unconventional” secretion, where proteins without a hitherto unknown signal are secreted, possibly in conditions of starvation. In this work, we analyse a set of 202 RNA binding mammalian proteins, whose unconventional secretion has recently been established. Analysis of these proteins secreted by LC3 mediation, the largest unconventionally secreted dataset to our knowledge, identifies the role of KKX motif as well as triacidic amino acid motif in unconventional secretion, the latter being an extension of the recent implicated diacidic amino acid motif. Further data analysis evolves a hypothesis on the sequence or structural proximity of the triacidic or KKX motifs to the LC3 interacting region, and a phosphorylatable amino acid such as serine as a statistically significant feature among these unconventionally secreted proteins. This hypothesis, although needs to be validated in experiments that challenge the specific details of each of these aspects, appears to be one of the early steps in defining what may be a plausible signal for unconventional protein secretion.
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Affiliation(s)
- Malay Ranjan Biswal
- Computational Biology, Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bangalore, India
| | - Sreedevi Padmanabhan
- Autophagy Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bangalore, India
| | - Ravi Manjithaya
- Autophagy Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bangalore, India
- *Correspondence: Ravi Manjithaya, ; Meher K. Prakash,
| | - Meher K. Prakash
- Computational Biology, Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bangalore, India
- *Correspondence: Ravi Manjithaya, ; Meher K. Prakash,
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19
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Resurrecting Golgi proteins to grasp Golgi ribbon formation and self-association under stress. Int J Biol Macromol 2022; 194:264-275. [PMID: 34861272 DOI: 10.1016/j.ijbiomac.2021.11.173] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 11/22/2021] [Accepted: 11/24/2021] [Indexed: 11/23/2022]
Abstract
The Golgi complex is an essential organelle of the eukaryotic exocytic pathway. A subfamily of Golgi matrix proteins, called GRASPs, is central in stress-induced unconventional secretion, Golgi dynamics during mitosis/apoptosis, and Golgi ribbon formation. The Golgi ribbon is vertebrate-specific and correlates with the appearance of two GRASP paralogues and two Golgins (GM130/Golgin45), which form specific GRASP-Golgin pairs. The molecular details of their appearance only in Metazoans are unknown. Moreover, despite new functionalities supported by GRASP paralogy, little is known about their structural and evolutionary differences. Here, we used ancestor sequence reconstruction and biophysical/biochemical approaches to assess the evolution of GRASPs structure/dynamics, fibrillation, and how they started anchoring their Golgin partners. Our data showed that a GRASP ancestor anchored Golgins before gorasp gene duplication in Metazoans. After gene duplication, variations within the GRASP binding pocket determined which paralogue would recruit which Golgin. These interactions are responsible for their specific Golgi location and Golgi ribbon appearance. We also suggest that GRASPs have a long-standing capacity to form supramolecular structures, affecting their participation in stress-induced processes.
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20
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De Morais JA, Zelanis A. Bioinformatic reanalysis of public proteomics data reveals that nuclear proteins are recurrent in cancer secretomes. Traffic 2021; 23:98-108. [PMID: 34806804 DOI: 10.1111/tra.12827] [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: 08/12/2021] [Revised: 11/05/2021] [Accepted: 11/18/2021] [Indexed: 11/27/2022]
Abstract
Proteins secreted by tumoral cells (cancer secretomes) have been continuously associated with cancer development and progression processes. In this context, secreted proteins contribute to the signaling mechanisms related to tumor growth and spreading and studies on tumor secretomes provide valuable clues on putative tumor biomarkers. Although the in vitro identification of intracellular proteins in cancer secretome studies has usually been associated with contamination derived from cell lysis or fetal bovine serum, accumulated evidence reports on intracellular proteins with moonlighting functions in the extracellular environment. In this study, we performed a systematic reanalysis of public proteomics data regarding different cancer secretomes, aiming to identify intracellular proteins potentially secreted by tumor cells via unconventional secretion pathways. We found a similar repertoire of unconventionally secreted proteins, including the recurrent identification of nuclear proteins secreted by different cancer cells. In addition, in some cancer types, immunohistochemical data were in line with proteomics identifications and suggested that nuclear proteins might relocate from the nucleus to the cytoplasm. Both the presence of nuclear proteins and the likely unconventional secretion of such proteins may comprise biological signatures of malignant transformation in distinct cancer types and may be targeted for further analysis aiming at the prognostic/therapeutic value of such features.
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Affiliation(s)
- Juliana A De Morais
- Functional Proteomics Laboratory, Institute of Science and Technology, Federal University of São Paulo, UNIFESP, São José dos Campos, São Paulo, Brazil
| | - André Zelanis
- Functional Proteomics Laboratory, Institute of Science and Technology, Federal University of São Paulo, UNIFESP, São José dos Campos, São Paulo, Brazil
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21
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Si J, Pei Y, Ji P, Zhang X, Xu R, Qiao H, Shen D, Peng H, Dou D. PsGRASP, a Golgi Reassembly Stacking Protein in Phytophthora sojae, Is Required for Mycelial Growth, Stress Responses, and Plant Infection. Front Microbiol 2021; 12:702632. [PMID: 34305870 PMCID: PMC8297711 DOI: 10.3389/fmicb.2021.702632] [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: 04/29/2021] [Accepted: 06/11/2021] [Indexed: 01/21/2023] Open
Abstract
Golgi reassembly stacking proteins (GRASPs) play important roles in Golgi structure formation, ER stress response, and unconventional secretion in eukaryotic cells. However, GRASP functions in oomycetes haven’t been adequately characterized. Here, we report the identification and functional analysis of PsGRASP, a GRASP-encoding gene from the soybean-infecting oomycete Phytophthora sojae. Transcriptional profiling showed that PsGRASP expression is up-regulated at the infection stages. PsGRASP knockout mutants were created using the CRISPR/Cas9 system. These mutants exhibited impaired vegetative growth, zoospore release and virulence. PsGRASP was involved ER stress responses and altered laccase activity. Our work suggests that PsGRASP is crucial for P. sojae development and pathogenicity.
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Affiliation(s)
- Jierui Si
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, China
| | - Yong Pei
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, China
| | - Peiyun Ji
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, China
| | - Xiong Zhang
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, China
| | - Ruofei Xu
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, China
| | - Huijun Qiao
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, China
| | - Danyu Shen
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, China
| | - Hao Peng
- Department of Crop and Soil Sciences, Washington State University, Pullman, WA, United States
| | - Daolong Dou
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, China
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22
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Nüchel J, Tauber M, Nolte JL, Mörgelin M, Türk C, Eckes B, Demetriades C, Plomann M. An mTORC1-GRASP55 signaling axis controls unconventional secretion to reshape the extracellular proteome upon stress. Mol Cell 2021; 81:3275-3293.e12. [PMID: 34245671 PMCID: PMC8382303 DOI: 10.1016/j.molcel.2021.06.017] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 04/21/2021] [Accepted: 06/14/2021] [Indexed: 01/13/2023]
Abstract
Cells communicate with their environment via surface proteins and secreted factors. Unconventional protein secretion (UPS) is an evolutionarily conserved process, via which distinct cargo proteins are secreted upon stress. Most UPS types depend upon the Golgi-associated GRASP55 protein. However, its regulation and biological role remain poorly understood. Here, we show that the mechanistic target of rapamycin complex 1 (mTORC1) directly phosphorylates GRASP55 to maintain its Golgi localization, thus revealing a physiological role for mTORC1 at this organelle. Stimuli that inhibit mTORC1 cause GRASP55 dephosphorylation and relocalization to UPS compartments. Through multiple, unbiased, proteomic analyses, we identify numerous cargoes that follow this unconventional secretory route to reshape the cellular secretome and surfactome. Using MMP2 secretion as a proxy for UPS, we provide important insights on its regulation and physiological role. Collectively, our findings reveal the mTORC1-GRASP55 signaling hub as the integration point in stress signaling upstream of UPS and as a key coordinator of the cellular adaptation to stress. mTORC1 phosphorylates GRASP55 directly at the Golgi in non-stressed cells mTORC1 inactivation by stress leads to GRASP55 dephosphorylation and relocalization GRASP55 relocalization to autophagosomes and MVBs drives UPS of selected cargo mTORC1-GRASP55 link cellular stress to changes in the extracellular proteome via UPS
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Affiliation(s)
- Julian Nüchel
- Max Planck Institute for Biology of Ageing (MPI-AGE), 50931 Cologne, Germany; University of Cologne, Faculty of Medicine and University Hospital Cologne, Center for Biochemistry, 50931 Cologne, Germany
| | - Marina Tauber
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Center for Biochemistry, 50931 Cologne, Germany
| | - Janica L Nolte
- University of Cologne, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), 50931 Cologne, Germany
| | | | - Clara Türk
- University of Cologne, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), 50931 Cologne, Germany
| | - Beate Eckes
- University of Cologne, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), 50931 Cologne, Germany; University of Cologne, Faculty of Medicine and University Hospital Cologne, Translational Matrix Biology, 50931 Cologne, Germany
| | - Constantinos Demetriades
- Max Planck Institute for Biology of Ageing (MPI-AGE), 50931 Cologne, Germany; University of Cologne, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), 50931 Cologne, Germany.
| | - Markus Plomann
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Center for Biochemistry, 50931 Cologne, Germany.
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23
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Row S, Huang YC, Deng WM. Developmental regulation of oocyte lipid intake through 'patent' follicular epithelium in Drosophila melanogaster. iScience 2021; 24:102275. [PMID: 33817579 PMCID: PMC8005764 DOI: 10.1016/j.isci.2021.102275] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 02/19/2021] [Accepted: 03/02/2021] [Indexed: 01/20/2023] Open
Abstract
Epithelia form protective permeability barriers that selectively allow the exchange of material while maintaining tissue integrity under extreme mechanical, chemical, and bacterial loads. Here, we report in the Drosophila follicular epithelium a developmentally regulated and evolutionarily conserved process "patency", wherein a breach is created in the epithelium at tricellular contacts during mid-vitellogenesis. In Drosophila, patency exhibits a strict temporal range potentially delimited by the transcription factor Tramtrack69 and a spatial pattern influenced by the dorsal-anterior signals of the follicular epithelium. Crucial for growth and lipid uptake by the oocyte, patency is also exploited by endosymbionts such as Spiroplasma pulsonii. Our findings reveal an evolutionarily conserved and developmentally regulated non-typical epithelial function in a classic model system.
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Affiliation(s)
- Sarayu Row
- Department of Biological Science, Florida State University, Tallahassee, FL 32306-4295, USA
| | - Yi-Chun Huang
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Wu-Min Deng
- Department of Biological Science, Florida State University, Tallahassee, FL 32306-4295, USA
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70112, USA
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24
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Grond R, Veenendaal T, Duran JM, Raote I, van Es JH, Corstjens S, Delfgou L, El Haddouti B, Malhotra V, Rabouille C. The function of GORASPs in Golgi apparatus organization in vivo. J Cell Biol 2021; 219:151880. [PMID: 32573693 PMCID: PMC7480117 DOI: 10.1083/jcb.202004191] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 05/29/2020] [Accepted: 06/08/2020] [Indexed: 12/14/2022] Open
Abstract
In vitro experiments have shown that GRASP65 (GORASP1) and GRASP55 (GORASP2) proteins function in stacking Golgi cisternae. However, in vivo depletion of GORASPs in metazoans has given equivocal results. We have generated a mouse lacking both GORASPs and find that Golgi cisternae remained stacked. However, the stacks are disconnected laterally from each other, and the cisternal cross-sectional diameters are significantly reduced compared with their normal counterparts. These data support earlier findings on the role of GORASPs in linking stacks, and we suggest that unlinking of stacks likely affects dynamic control of COPI budding and vesicle fusion at the rims. The net result is that cisternal cores remain stacked, but cisternal diameter is reduced by rim consumption.
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Affiliation(s)
- Rianne Grond
- Hubrecht Institute of the Royal Netherlands Academy of Arts and Sciences and Utrecht Medical Center Utrecht, Utrecht, Netherlands
| | - Tineke Veenendaal
- Department of Cell Biology, Utrecht Medical Center Utrecht, Utrecht, Netherlands
| | - Juan M Duran
- 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
| | - Johan H van Es
- Hubrecht Institute of the Royal Netherlands Academy of Arts and Sciences and Utrecht Medical Center Utrecht, Utrecht, Netherlands
| | - Sebastiaan Corstjens
- Hubrecht Institute of the Royal Netherlands Academy of Arts and Sciences and Utrecht Medical Center Utrecht, Utrecht, Netherlands
| | - Laura Delfgou
- Hubrecht Institute of the Royal Netherlands Academy of Arts and Sciences and Utrecht Medical Center Utrecht, Utrecht, Netherlands
| | - Benaissa El Haddouti
- Hubrecht Institute of the Royal Netherlands Academy of Arts and Sciences and Utrecht Medical Center Utrecht, Utrecht, Netherlands
| | - Vivek Malhotra
- Centre for Genomic Regulation, The Barcelona Institute of Science and Technology, Barcelona, Spain.,Universitat Pompeu Fabra, Barcelona, Spain.,Institució Catalana de Recerca i Estudis Avançats, Barcelona, Spain
| | - Catherine Rabouille
- Hubrecht Institute of the Royal Netherlands Academy of Arts and Sciences and Utrecht Medical Center Utrecht, Utrecht, Netherlands.,Department of Cell Biology, Utrecht Medical Center Utrecht, Utrecht, Netherlands.,Department of Biological Science of Cell and Systems, Utrecht Medical Center Groningen, Groningen, Netherlands
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25
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Padmanabhan S, Manjithaya R. Facets of Autophagy Based Unconventional Protein Secretion-The Road Less Traveled. Front Mol Biosci 2020; 7:586483. [PMID: 33363205 PMCID: PMC7755989 DOI: 10.3389/fmolb.2020.586483] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 09/07/2020] [Indexed: 12/28/2022] Open
Abstract
Unconventional protein secretion (UCPS) of leaderless proteins bypasses the conventional endoplasmic reticulum (ER)-Golgi route. The proportion of UCPS in the secretome varies tremendously across eukaryotes. Interestingly, macroautophagy, an intracellular recycling process that is generally involved in cargo degradation, also participates in UCPS. This emerging field of secretory mode of autophagy is underexplored and has several unanswered questions regarding the composition of players, cargo, and the mechanisms that drive it. As secretomes vary considerably across cell types and physiological conditions, the contribution of secretory autophagy in healthy and pathophysiological states remain to be elucidated. Recent studies have begun to shed light on this enigmatic process.
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Affiliation(s)
- Sreedevi Padmanabhan
- Autophagy Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India
| | - Ravi Manjithaya
- Autophagy Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India.,Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India
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26
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The exquisite structural biophysics of the Golgi Reassembly and Stacking Proteins. Int J Biol Macromol 2020; 164:3632-3644. [DOI: 10.1016/j.ijbiomac.2020.08.203] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 08/20/2020] [Accepted: 08/26/2020] [Indexed: 12/13/2022]
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27
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Zhang X, Wang Y. Nonredundant Roles of GRASP55 and GRASP65 in the Golgi Apparatus and Beyond. Trends Biochem Sci 2020; 45:1065-1079. [PMID: 32893104 PMCID: PMC7641999 DOI: 10.1016/j.tibs.2020.08.001] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 07/06/2020] [Accepted: 08/03/2020] [Indexed: 12/20/2022]
Abstract
It has been demonstrated that two Golgi stacking proteins, GRASP55 and GRASP65, self-interact to form trans-oligomers that tether adjacent Golgi membranes into stacks and ribbons in mammalian cells. This ensures proper functioning of the Golgi apparatus in protein trafficking and processing. More recently, GRASP proteins have drawn extensive attention from researchers due to their diverse and essential roles in and out of the Golgi in different organisms. In this review, we summarize their established roles in Golgi structure formation and function under physiological conditions. We then highlight the emerging and divergent roles for individual GRASP proteins, focusing on GRASP65 in cell migration and apoptosis and GRASP55 in unconventional protein secretion and autophagy under stress or pathological conditions.
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Affiliation(s)
- Xiaoyan Zhang
- College of Biomedicine and Health, Huazhong Agricultural University, Wuhan, China; College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China.
| | - Yanzhuang Wang
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA; Department of Neurology, University of Michigan School of Medicine, Ann Arbor, MI, USA.
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28
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Kalebic N, Huttner WB. Basal Progenitor Morphology and Neocortex Evolution. Trends Neurosci 2020; 43:843-853. [PMID: 32828546 DOI: 10.1016/j.tins.2020.07.009] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 07/22/2020] [Accepted: 07/29/2020] [Indexed: 11/28/2022]
Abstract
The evolutionary expansion of the mammalian neocortex is widely considered to be a basis of increased cognitive abilities. This expansion is a consequence of the enhanced production of neurons during the fetal/embryonic development of the neocortex, which in turn reflects an increased proliferative capacity of neural progenitor cells; in particular basal progenitors (BPs). The remarkable heterogeneity of BP subtypes across mammals, notably their various morphotypes and molecular fingerprints, which has recently been revealed, corroborates the importance of BPs for neocortical expansion. Here, we argue that the morphology of BPs is a key cell biological basis for maintaining their high proliferative capacity and therefore plays crucial roles in the evolutionary expansion of the neocortex.
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Affiliation(s)
- Nereo Kalebic
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany; Human Technopole, Milan, Italy.
| | - Wieland B Huttner
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.
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29
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van Ziel AM, Scheper W. The UPR in Neurodegenerative Disease: Not Just an Inside Job. Biomolecules 2020; 10:biom10081090. [PMID: 32707908 PMCID: PMC7465596 DOI: 10.3390/biom10081090] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 07/16/2020] [Accepted: 07/20/2020] [Indexed: 12/26/2022] Open
Abstract
Neurons are highly specialized cells that continuously and extensively communicate with other neurons, as well as glia cells. During their long lifetime, the post-mitotic neurons encounter many stressful situations that can disrupt protein homeostasis (proteostasis). The importance of tight protein quality control is illustrated by neurodegenerative disorders where disturbed neuronal proteostasis causes neuronal dysfunction and loss. For their unique function, neurons require regulated and long-distance transport of membrane-bound cargo and organelles. This highlights the importance of protein quality control in the neuronal endomembrane system, to which the unfolded protein response (UPR) is instrumental. The UPR is a highly conserved stress response that is present in all eukaryotes. However, recent studies demonstrate the existence of cell-type-specific aspects of the UPR, as well as cell non-autonomous UPR signaling. Here we discuss these novel insights in view of the complex cellular architecture of the brain and the implications for neurodegenerative diseases.
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Affiliation(s)
- Anna Maria van Ziel
- Department of Clinical Genetics, Amsterdam University Medical Centers location VUmc, 1081 HV Amsterdam, The Netherlands;
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Vrije Universiteit (VU), 1081 HV Amsterdam, The Netherlands
| | - Wiep Scheper
- Department of Clinical Genetics, Amsterdam University Medical Centers location VUmc, 1081 HV Amsterdam, The Netherlands;
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Vrije Universiteit (VU), 1081 HV Amsterdam, The Netherlands
- Correspondence: ; Tel.: +31-20-5982771
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30
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Santa-Cruz Mateos C, Valencia-Expósito A, Palacios IM, Martín-Bermudo MD. Integrins regulate epithelial cell shape by controlling the architecture and mechanical properties of basal actomyosin networks. PLoS Genet 2020; 16:e1008717. [PMID: 32479493 PMCID: PMC7263567 DOI: 10.1371/journal.pgen.1008717] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 03/16/2020] [Indexed: 01/01/2023] Open
Abstract
Forces generated by the actomyosin cytoskeleton are key contributors to many morphogenetic processes. The actomyosin cytoskeleton organises in different types of networks depending on intracellular signals and on cell-cell and cell-extracellular matrix (ECM) interactions. However, actomyosin networks are not static and transitions between them have been proposed to drive morphogenesis. Still, little is known about the mechanisms that regulate the dynamics of actomyosin networks during morphogenesis. This work uses the Drosophila follicular epithelium, real-time imaging, laser ablation and quantitative analysis to study the role of integrins on the regulation of basal actomyosin networks organisation and dynamics and the potential contribution of this role to cell shape. We find that elimination of integrins from follicle cells impairs F-actin recruitment to basal medial actomyosin stress fibers. The available F-actin redistributes to the so-called whip-like structures, present at tricellular junctions, and into a new type of actin-rich protrusions that emanate from the basal cortex and project towards the medial region. These F-actin protrusions are dynamic and changes in total protrusion area correlate with periodic cycles of basal myosin accumulation and constriction pulses of the cell membrane. Finally, we find that follicle cells lacking integrin function show increased membrane tension and reduced basal surface. Furthermore, the actin-rich protrusions are responsible for these phenotypes as their elimination in integrin mutant follicle cells rescues both tension and basal surface defects. We thus propose that the role of integrins as regulators of stress fibers plays a key role on controlling epithelial cell shape, as integrin disruption promotes reorganisation into other types of actomyosin networks, in a manner that interferes with proper expansion of epithelial basal surfaces. Morphogenesis involves global changes in tissue architecture driven by cell shape changes. Mechanical forces generated by actomyosin networks and force transmission through adhesive complexes power these changes. The actomyosin cytoskeleton organises in different types of networks, which localise to precise regions and perform distinct roles. However, they are rarely independent and, often, reorganisation of a given structure can promote the formation of another, conversions proposed to underlie many morphogenetic processes. Nonetheless, the mechanisms controlling actomyosin network dynamics during morphogenesis remain poorly characterised. Here, using the Drosophila follicular epithelium, we show that cell-ECM interactions mediated by integrins are required for the correct distribution of actin in the different actin networks. Elimination of integrins results in redistribution of actin from stress fibers into a new type of protrusions that dynamically emanate from the cortex and extend into the stress fibers. Changes in area protrusions correlate with bursts of myosin accumulated in stress fibers and constriction pulses of the cell membrane. We also found that integrin mutant cells show increased membrane tension and reduced basal cell surface. As these defects are rescued by eliminating the F-actin protrusions, we believe these structures prevent proper basal surface growth. Thus, we propose that integrin function as regulators of stress fibers assembly and maintenance controls epithelial cell shape, as its disruption promotes reorganisation into other actomyosin networks, conversions that interfere with proper epithelial basal surface expansion.
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Affiliation(s)
- Carmen Santa-Cruz Mateos
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide/CSIC/JA, Carretera de Utrera,Sevilla, Spain
| | - Andrea Valencia-Expósito
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide/CSIC/JA, Carretera de Utrera,Sevilla, Spain
| | - Isabel M. Palacios
- School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | - María D. Martín-Bermudo
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide/CSIC/JA, Carretera de Utrera,Sevilla, Spain
- * E-mail:
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31
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Zhang M, Liu L, Lin X, Wang Y, Li Y, Guo Q, Li S, Sun Y, Tao X, Zhang D, Lv X, Zheng L, Ge L. A Translocation Pathway for Vesicle-Mediated Unconventional Protein Secretion. Cell 2020; 181:637-652.e15. [PMID: 32272059 DOI: 10.1016/j.cell.2020.03.031] [Citation(s) in RCA: 168] [Impact Index Per Article: 33.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 01/22/2020] [Accepted: 03/11/2020] [Indexed: 12/13/2022]
Abstract
Many cytosolic proteins lacking a signal peptide, called leaderless cargoes, are secreted through unconventional secretion. Vesicle trafficking is a major pathway involved. It is unclear how leaderless cargoes enter into the vesicle. Here, we find a translocation pathway regulating vesicle entry and secretion of leaderless cargoes. We identify TMED10 as a protein channel for the vesicle entry and secretion of many leaderless cargoes. The interaction of TMED10 C-terminal region with a motif in the cargo accounts for the selective release of the cargoes. In an in vitro reconstitution assay, TMED10 directly mediates the membrane translocation of leaderless cargoes into the liposome, which is dependent on protein unfolding and enhanced by HSP90s. In the cell, TMED10 localizes on the endoplasmic reticulum (ER)-Golgi intermediate compartment and directs the entry of cargoes into this compartment. Furthermore, cargo induces the formation of TMED10 homo-oligomers which may act as a protein channel for cargo translocation.
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Affiliation(s)
- Min Zhang
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Lei Liu
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Xubo Lin
- Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing 100191, China
| | - Yang Wang
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Ying Li
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Qing Guo
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Shulin Li
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yuxin Sun
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Xuan Tao
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Di Zhang
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Xiachen Lv
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Li Zheng
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Liang Ge
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China.
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32
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Grasp55 -/- mice display impaired fat absorption and resistance to high-fat diet-induced obesity. Nat Commun 2020; 11:1418. [PMID: 32184397 PMCID: PMC7078302 DOI: 10.1038/s41467-020-14912-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 01/31/2020] [Indexed: 12/27/2022] Open
Abstract
The Golgi apparatus plays a central role in the intracellular transport of macromolecules. However, molecular mechanisms of Golgi-mediated lipid transport remain poorly understood. Here, we show that genetic inactivation of the Golgi-resident protein GRASP55 in mice reduces whole-body fat mass via impaired intestinal fat absorption and evokes resistance to high-fat diet induced body weight gain. Mechanistic analyses reveal that GRASP55 participates in the Golgi-mediated lipid droplet (LD) targeting of some LD-associated lipases, such as ATGL and MGL, which is required for sustained lipid supply for chylomicron assembly and secretion. Consequently, GRASP55 deficiency leads to reduced chylomicron secretion and abnormally large LD formation in intestinal epithelial cells upon exogenous lipid challenge. Notably, deletion of dGrasp in Drosophila causes similar defects of lipid accumulation in the midgut. These results highlight the importance of the Golgi complex in cellular lipid regulation, which is evolutionary conserved, and uncover potential therapeutic targets for obesity-associated diseases. The physiological roles of the Golgi reassembly-stacking protein 55 (GRASP55/GORASP55) remain largely elusive. Here, the authors show that the Golgi-resident protein GRASP55 plays a crucial role in lipid homeostasis by regulating intestinal lipid uptake.
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33
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Mendes LFS, Batista MRB, Judge PJ, Watts A, Redfield C, Costa-Filho AJ. Conformational flexibility of GRASPs and their constituent PDZ subdomains reveals structural basis of their promiscuous interactome. FEBS J 2020; 287:3255-3272. [PMID: 31920006 DOI: 10.1111/febs.15206] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 11/19/2019] [Accepted: 01/08/2020] [Indexed: 01/04/2023]
Abstract
The Golgi complex is a central component of the secretory pathway, responsible for several critical cellular functions in eukaryotes. The complex is organized by the Golgi matrix that includes the Golgi reassembly and stacking protein (GRASP), which was shown to be involved in cisternae stacking and lateral linkage in metazoan. GRASPs also have critical roles in other processes, with an unusual ability to interact with several different binding partners. The conserved N terminus of the GRASP family includes two PSD-95, DLG, and ZO-1 (PDZ) domains. Previous crystallographic studies of orthologues suggest that PDZ1 and PDZ2 have similar conformations and secondary structure content. However, PDZ1 alone mediates nearly all interactions between GRASPs and their partners. In this work, NMR, synchrotron radiation CD, and molecular dynamics (MD) were used to examine the structure, flexibility, and stability of the two constituent PDZ domains. GRASP PDZs are structured in an unusual β3 α1 β4 β5 α2 β6 β1 β2 secondary structural arrangement and NMR data indicate that the PDZ1 binding pocket is formed by a stable β2 -strand and a more flexible and unstable α2 -helix, suggesting an explanation for the higher PDZ1 promiscuity. The conformational free energy profiles of the two PDZ domains were calculated using MD simulations. The data suggest that, after binding, the protein partner significantly reduces the conformational space that GRASPs can access by stabilizing one particular conformation, in a partner-dependent fashion. The structural flexibility of PDZ1, modulated by PDZ2, and the coupled, coordinated movement between the two PDZs enable GRASPs to interact with multiple partners, allowing them to function as promiscuous, multitasking proteins.
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Affiliation(s)
- Luis Felipe S Mendes
- Molecular Biophysics Laboratory, Ribeirão Preto School of Philosophy, Sciences and Literature, Physics Department, University of São Paulo, Ribeirão Preto, Brazil.,Department of Biochemistry, University of Oxford, UK
| | - Mariana R B Batista
- Molecular Biophysics Laboratory, Ribeirão Preto School of Philosophy, Sciences and Literature, Physics Department, University of São Paulo, Ribeirão Preto, Brazil
| | - Peter J Judge
- Department of Biochemistry, University of Oxford, UK
| | - Anthony Watts
- Department of Biochemistry, University of Oxford, UK
| | | | - Antonio J Costa-Filho
- Molecular Biophysics Laboratory, Ribeirão Preto School of Philosophy, Sciences and Literature, Physics Department, University of São Paulo, Ribeirão Preto, Brazil
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34
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Saraste J, Prydz K. A New Look at the Functional Organization of the Golgi Ribbon. Front Cell Dev Biol 2019; 7:171. [PMID: 31497600 PMCID: PMC6713163 DOI: 10.3389/fcell.2019.00171] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 08/07/2019] [Indexed: 12/14/2022] Open
Abstract
A characteristic feature of vertebrate cells is a Golgi ribbon consisting of multiple cisternal stacks connected into a single-copy organelle next to the centrosome. Despite numerous studies, the mechanisms that link the stacks together and the functional significance of ribbon formation remain poorly understood. Nevertheless, these questions are of considerable interest, since there is increasing evidence that Golgi fragmentation – the unlinking of the stacks in the ribbon – is intimately connected not only to normal physiological processes, such as cell division and migration, but also to pathological states, including neurodegeneration and cancer. Challenging a commonly held view that ribbon architecture involves the formation of homotypic tubular bridges between the Golgi stacks, we present an alternative model, based on direct interaction between the biosynthetic (pre-Golgi) and endocytic (post-Golgi) membrane networks and their connection with the centrosome. We propose that the central domains of these permanent pre- and post-Golgi networks function together in the biogenesis and maintenance of the more transient Golgi stacks, and thereby establish “linker compartments” that dynamically join the stacks together. This model provides insight into the reversible fragmentation of the Golgi ribbon that takes place in dividing and migrating cells and its regulation along a cell surface – Golgi – centrosome axis. Moreover, it helps to understand transport pathways that either traverse or bypass the Golgi stacks and the positioning of the Golgi apparatus in differentiated neuronal, epithelial, and muscle cells.
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Affiliation(s)
- Jaakko Saraste
- Department of Biomedicine and Molecular Imaging Center, University of Bergen, Bergen, Norway
| | - Kristian Prydz
- Department of Biosciences, University of Oslo, Oslo, Norway
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35
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Ahat E, Li J, Wang Y. New Insights Into the Golgi Stacking Proteins. Front Cell Dev Biol 2019; 7:131. [PMID: 31380369 PMCID: PMC6660245 DOI: 10.3389/fcell.2019.00131] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 07/03/2019] [Indexed: 12/14/2022] Open
Abstract
The Golgi stacking proteins, GRASP55 and GRASP65, are best known for their roles in Golgi structure formation. These peripheral Golgi proteins form trans-oligomers that hold the flat cisternal membranes into stacks. Depletion of both GRASP proteins in cells disrupts the Golgi stack structure, increases protein trafficking, but impairs accurate glycosylation, and sorting. Golgi unstacking by GRASPs depletion also reduces cell adhesion and migration in an integrin-dependent manner. In addition to Golgi structure formation and regulation of cellular activities, GRASPs, in particular GRASP55, have recently drawn attention in their roles in autophagy, and unconventional secretion. In autophagy, GRASP55 senses the energy level by O-GlcNAcylation, which regulates GRASP55 translocation from the Golgi to the autophagosome-lysosome interface, where it interacts with LC3 and LAMP2 to facilitate autophagosome-lysosome fusion. This newly discovered function of GRASP55 in autophagy may help explain its role in the stress-induced, autophagosome-dependent unconventional secretion. In this review, we summarize the emerging functions of the GRASP proteins, focusing on their roles in cell adhesion and migration, autophagy, unconventional secretion, as well as on novel GRASP-interacting proteins.
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Affiliation(s)
- Erpan Ahat
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, United States
| | - Jie Li
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, United States
| | - Yanzhuang Wang
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, United States
- Department of Neurology, University of Michigan School of Medicine, Ann Arbor, MI, United States
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36
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Abstract
Regulated synthesis and movement of proteins between cellular organelles are central to diverse forms of biological adaptation and plasticity. In neurons, the repertoire of channel, receptor, and adhesion proteins displayed on the cell surface directly impacts cellular development, morphology, excitability, and synapse function. The immensity of the neuronal surface membrane and its division into distinct functional domains present a challenging landscape over which proteins must navigate to reach their appropriate functional domains. This problem becomes more complex considering that neuronal protein synthesis is continuously refined in space and time by neural activity. Here we review our current understanding of how integral membrane and secreted proteins important for neuronal function travel from their sites of synthesis to their functional destinations. We discuss how unique adaptations to the function and distribution of neuronal secretory organelles may facilitate local protein trafficking at remote sites in neuronal dendrites to support diverse forms of synaptic plasticity.
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Affiliation(s)
- Matthew J Kennedy
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, Colorado 80045, USA;
| | - Cyril Hanus
- Institute for Psychiatry and Neurosciences of Paris, Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Paris, 75014 Paris, France;
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Unconventional secretory pathway activation restores hair cell mechanotransduction in an USH3A model. Proc Natl Acad Sci U S A 2019; 116:11000-11009. [PMID: 31097578 DOI: 10.1073/pnas.1817500116] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The pathogenic variant c.144T>G (p.N48K) in the clarin1 gene (CLRN1) results in progressive loss of vision and hearing in Usher syndrome IIIA (USH3A) patients. CLRN1 is predicted to be an essential protein in hair bundles, the mechanosensory structure of hair cells critical for hearing and balance. When expressed in animal models, CLRN1 localizes to the hair bundle, whereas glycosylation-deficient CLRN1N48K aggregates in the endoplasmic reticulum, with only a fraction reaching the bundle. We hypothesized that the small amount of CLRN1N48K that reaches the hair bundle does so via an unconventional secretory pathway and that activation of this pathway could be therapeutic. Using genetic and pharmacological approaches, we find that clarin1 knockout (clrn1 KO/KO ) zebrafish that express the CLRN1 c.144T>G pathogenic variant display progressive hair cell dysfunction, and that CLRN1N48K is trafficked to the hair bundle via the GRASP55 cargo-dependent unconventional secretory pathway (GCUSP). On expression of GRASP55 mRNA, or on exposure to the drug artemisinin (which activates GCUSP), the localization of CLRN1N48K to the hair bundles was enhanced. Artemisinin treatment also effectively restored hair cell mechanotransduction and attenuated progressive hair cell dysfunction in clrn1 KO/KO larvae that express CLRN1 c.144T>G , highlighting the potential of artemisinin to prevent sensory loss in CLRN1 c.144T>G patients.
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van Ziel AM, Largo-Barrientos P, Wolzak K, Verhage M, Scheper W. Unconventional secretion factor GRASP55 is increased by pharmacological unfolded protein response inducers in neurons. Sci Rep 2019; 9:1567. [PMID: 30733486 PMCID: PMC6367349 DOI: 10.1038/s41598-018-38146-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 12/19/2018] [Indexed: 12/18/2022] Open
Abstract
Accumulation of misfolded proteins in the endoplasmic reticulum (ER), defined as ER stress, results in activation of the unfolded protein response (UPR). UPR activation is commonly observed in neurodegenerative diseases. ER stress can trigger unconventional secretion mediated by Golgi reassembly and stacking proteins (GRASP) relocalization in cell lines. Here we study the regulation of GRASP55 by the UPR upon pharmacological induction of ER stress in primary mouse neurons. We demonstrate that UPR activation induces mRNA and protein expression of GRASP55, but not GRASP65, in cortical neurons. UPR activation does not result in relocalization of GRASP55. UPR-induced GRASP55 expression is reduced by inhibition of the PERK pathway of the UPR and abolished by inhibition of the endonuclease activity of the UPR transducer IRE1. Expression of the IRE1 target XBP1s in the absence of ER stress is not sufficient to increase GRASP55 expression. Knockdown of GRASP55 affects neither induction nor recovery of the UPR. We conclude that the UPR regulates the unconventional secretion factor GRASP55 via a mechanism that requires the IRE1 and the PERK pathway of the UPR in neurons.
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Affiliation(s)
- Anna Maria van Ziel
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Vrije Universiteit (VU), Amsterdam, The Netherlands.,Clinical Genetics, Amsterdam UMC, location VUmc, Amsterdam, The Netherlands
| | - Pablo Largo-Barrientos
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Vrije Universiteit (VU), Amsterdam, The Netherlands
| | - Kimberly Wolzak
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Vrije Universiteit (VU), Amsterdam, The Netherlands
| | - Matthijs Verhage
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Vrije Universiteit (VU), Amsterdam, The Netherlands.,Clinical Genetics, Amsterdam UMC, location VUmc, Amsterdam, The Netherlands
| | - Wiep Scheper
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Vrije Universiteit (VU), Amsterdam, The Netherlands. .,Clinical Genetics, Amsterdam UMC, location VUmc, Amsterdam, The Netherlands. .,Alzheimer Center, Amsterdam UMC, location VUmc, Amsterdam, The Netherlands.
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39
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Zhao Z, Kesti T, Uğurlu H, Baur AS, Fagerlund R, Saksela K. Tyrosine phosphorylation directs TACE into extracellular vesicles via unconventional secretion. Traffic 2019; 20:202-212. [PMID: 30569492 DOI: 10.1111/tra.12630] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 12/17/2018] [Accepted: 12/18/2018] [Indexed: 02/06/2023]
Abstract
When studying how HIV-1 Nef can promote packaging of the proinflammatory transmembrane protease TACE (tumor necrosis factor-α converting enzyme) into extracellular vesicles (EVs) we have revealed a novel tyrosine kinase-regulated unconventional protein secretion (UPS) pathway for TACE. When TACE was expressed without its trafficking cofactor iRhom allosteric Hck activation by Nef triggered translocation of TACE into EVs. This process was insensitive to blocking of classical secretion by inhibiting endoplasmic reticulum (ER) to Golgi transport, and involved a distinct form of TACE devoid of normal glycosylation and incompletely processed for prodomain removal. Like most other examples of UPS this process was Golgi reassembly stacking protein (GRASP)-dependent but was not associated with ER stress. These data indicate that Hck-activated UPS provides an alternative pathway for TACE secretion that can bypass iRhom-dependent ER to Golgi transfer, and suggest that tyrosine phosphorylation might have a more general role in regulating UPS.
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Affiliation(s)
- Zhe Zhao
- Department of Virology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Tapio Kesti
- Department of Virology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Hasan Uğurlu
- Department of Virology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Andreas S Baur
- Department of Dermatology, Translational Research Center, University Hospital Erlangen, Erlangen, Germany
| | - Riku Fagerlund
- Department of Virology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Kalle Saksela
- Department of Virology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
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40
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The Golgi Apparatus in Polarized Neuroepithelial Stem Cells and Their Progeny: Canonical and Noncanonical Features. Results Probl Cell Differ 2019; 67:359-375. [PMID: 31435803 DOI: 10.1007/978-3-030-23173-6_15] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Neurons forming the central nervous system are generated by neural stem and progenitor cells, via a process called neurogenesis (Götz and Huttner, Nat Rev Mol Cell Biol, 6:777-788, 2005). In this book chapter, we focus on neurogenesis in the dorsolateral telencephalon, the rostral-most region of the neural tube, which contains the part of the central nervous system that is most expanded in mammals (Borrell and Reillo, Dev Neurobiol, 72:955-971, 2012; Wilsch-Bräuninger et al., Curr Opin Neurobiol 39:122-132, 2016). We will discuss recent advances in the dissection of the cell biological mechanisms of neurogenesis, with particular attention to the organization and function of the Golgi apparatus and its relationship to the centrosome.
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Claude-Taupin A, Bissa B, Jia J, Gu Y, Deretic V. Role of autophagy in IL-1β export and release from cells. Semin Cell Dev Biol 2018; 83:36-41. [PMID: 29580970 PMCID: PMC6173661 DOI: 10.1016/j.semcdb.2018.03.012] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 03/20/2018] [Accepted: 03/20/2018] [Indexed: 01/12/2023]
Abstract
The autophagy pathway known also as macroautophagy (herein referred to as autophagy) is characterized by the formation of double-membrane organelles that capture cytosolic material. Based on pathway termination alternatives, autophagy has been divided into degradative and secretory. During degradative autophagy, autophagosomes typically fuse with lysosomes upon which the sequestered material is degraded. During secretory autophagy, instead of degradation the sequestered cargo is subjected to active secretion or passive release. In this review, we focus on the mechanisms of secretion/passive release of the potent pro-inflammatory cytokine IL-1β, as a prototypical leaderless cytosolic protein cargo studied in the context of secretory autophagy.
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Affiliation(s)
- Aurore Claude-Taupin
- Autophagy Inflammation and Metabolism Center of Biomedical Research Excellence, University of New Mexico Health Sciences Center, 915 Camino de Salud, NE, Albuquerque, NM 87131 USA; Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, 915 Camino de Salud, NE, Albuquerque, NM 87131 USA
| | - Bhawana Bissa
- Autophagy Inflammation and Metabolism Center of Biomedical Research Excellence, University of New Mexico Health Sciences Center, 915 Camino de Salud, NE, Albuquerque, NM 87131 USA; Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, 915 Camino de Salud, NE, Albuquerque, NM 87131 USA
| | - Jingyue Jia
- Autophagy Inflammation and Metabolism Center of Biomedical Research Excellence, University of New Mexico Health Sciences Center, 915 Camino de Salud, NE, Albuquerque, NM 87131 USA; Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, 915 Camino de Salud, NE, Albuquerque, NM 87131 USA
| | - Yuexi Gu
- Autophagy Inflammation and Metabolism Center of Biomedical Research Excellence, University of New Mexico Health Sciences Center, 915 Camino de Salud, NE, Albuquerque, NM 87131 USA; Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, 915 Camino de Salud, NE, Albuquerque, NM 87131 USA
| | - Vojo Deretic
- Autophagy Inflammation and Metabolism Center of Biomedical Research Excellence, University of New Mexico Health Sciences Center, 915 Camino de Salud, NE, Albuquerque, NM 87131 USA; Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, 915 Camino de Salud, NE, Albuquerque, NM 87131 USA.
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42
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Saraste J, Marie M. Intermediate compartment (IC): from pre-Golgi vacuoles to a semi-autonomous membrane system. Histochem Cell Biol 2018; 150:407-430. [PMID: 30173361 PMCID: PMC6182704 DOI: 10.1007/s00418-018-1717-2] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/27/2018] [Indexed: 12/19/2022]
Abstract
Despite its discovery more than three decades ago and well-established role in protein sorting and trafficking in the early secretory pathway, the intermediate compartment (IC) has remained enigmatic. The prevailing view is that the IC evolved as a specialized organelle to mediate long-distance endoplasmic reticulum (ER)–Golgi communication in metazoan cells, but is lacking in other eukaryotes, such as plants and fungi. However, this distinction is difficult to reconcile with the high conservation of the core machineries that regulate early secretory trafficking from yeast to man. Also, it has remained unclear whether the pleiomorphic IC components—vacuoles, tubules and vesicles—represent transient transport carriers or building blocks of a permanent pre-Golgi organelle. Interestingly, recent studies have revealed that the IC maintains its compositional, structural and spatial properties throughout the cell cycle, supporting a model that combines the dynamic and stable aspects of the organelle. Moreover, the IC has been assigned novel functions, such as cell signaling, Golgi-independent trafficking and autophagy. The emerging permanent nature of the IC and its connections with the centrosome and the endocytic recycling system encourage reconsideration of its relationship with the Golgi ribbon, role in Golgi biogenesis and ubiquitous presence in eukaryotic cells.
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Affiliation(s)
- Jaakko Saraste
- Department of Biomedicine and Molecular Imaging Center (MIC), University of Bergen, Jonas Lies vei 91, 5009, Bergen, Norway.
| | - Michaël Marie
- Department of Biomedicine and Molecular Imaging Center (MIC), University of Bergen, Jonas Lies vei 91, 5009, Bergen, Norway
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Kim J, Gee HY, Lee MG. Unconventional protein secretion – new insights into the pathogenesis and therapeutic targets of human diseases. J Cell Sci 2018; 131:131/12/jcs213686. [DOI: 10.1242/jcs.213686] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
ABSTRACT
Most secretory proteins travel through a well-documented conventional secretion pathway involving the endoplasmic reticulum (ER) and the Golgi complex. However, recently, it has been shown that a significant number of proteins reach the plasma membrane or extracellular space via unconventional routes. Unconventional protein secretion (UPS) can be divided into two types: (i) the extracellular secretion of cytosolic proteins that do not bear a signal peptide (i.e. leaderless proteins) and (ii) the cell-surface trafficking of signal-peptide-containing transmembrane proteins via a route that bypasses the Golgi. Understanding the UPS pathways is not only important for elucidating the mechanisms of intracellular trafficking pathways but also has important ramifications for human health, because many of the proteins that are unconventionally secreted by mammalian cells and microorganisms are associated with human diseases, ranging from common inflammatory diseases to the lethal genetic disease of cystic fibrosis. Therefore, it is timely and appropriate to summarize and analyze the mechanisms of UPS involvement in disease pathogenesis, as they may be of use for the development of new therapeutic approaches. In this Review, we discuss the intracellular trafficking pathways of UPS cargos, particularly those related to human diseases. We also outline the disease mechanisms and the therapeutic potentials of new strategies for treating UPS-associated diseases.
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Affiliation(s)
- Jiyoon Kim
- Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul 120-752, Korea
| | - Heon Yung Gee
- Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul 120-752, Korea
| | - Min Goo Lee
- Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul 120-752, Korea
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44
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González C, Cornejo VH, Couve A. Golgi bypass for local delivery of axonal proteins, fact or fiction? Curr Opin Cell Biol 2018; 53:9-14. [PMID: 29631154 DOI: 10.1016/j.ceb.2018.03.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 03/26/2018] [Accepted: 03/29/2018] [Indexed: 02/07/2023]
Abstract
Although translation of cytosolic proteins is well described in axons, much less is known about the synthesis, processing and trafficking of transmembrane and secreted proteins. A canonical rough endoplasmic reticulum or a stacked Golgi apparatus has not been detected in axons, generating doubts about the functionality of a local route. However, axons contain mRNAs for membrane and secreted proteins, translation factors, ribosomal components, smooth endoplasmic reticulum and post-endoplasmic reticulum elements that may contribute to local biosynthesis and plasma membrane delivery. Here we consider the evidence supporting a local secretory system in axons. We discuss exocytic elements and examples of autonomous axonal trafficking that impact development and maintenance. We also examine whether unconventional post-endoplasmic reticulum pathways may replace the canonical Golgi apparatus.
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Affiliation(s)
- Carolina González
- Department of Neuroscience, Facultad de Medicina, Universidad de Chile, Chile; Biomedical Neuroscience Institute (BNI), Facultad de Medicina, Universidad de Chile, Chile
| | - Víctor Hugo Cornejo
- Department of Neuroscience, Facultad de Medicina, Universidad de Chile, Chile; Biomedical Neuroscience Institute (BNI), Facultad de Medicina, Universidad de Chile, Chile
| | - Andrés Couve
- Department of Neuroscience, Facultad de Medicina, Universidad de Chile, Chile; Biomedical Neuroscience Institute (BNI), Facultad de Medicina, Universidad de Chile, Chile.
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45
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Gee HY, Kim J, Lee MG. Unconventional secretion of transmembrane proteins. Semin Cell Dev Biol 2018; 83:59-66. [PMID: 29580969 DOI: 10.1016/j.semcdb.2018.03.016] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 03/22/2018] [Accepted: 03/22/2018] [Indexed: 01/09/2023]
Abstract
Over the past 20 years it has become evident that eukaryotic cells utilize both conventional and unconventional pathways to deliver proteins to their target sites. Most proteins with a signal peptide and/or a transmembrane domain are conventionally transported through the endoplasmic reticulum to the Golgi apparatus and then to the plasma membrane. However, an increasing number of both soluble cargos (Type I, II, and III) and integral membrane proteins (Type IV) have been found to reach the plasma membrane via unconventional protein secretion (UPS) pathways that bypass the Golgi apparatus under certain conditions, such as cellular stress or development. Well-known examples of transmembrane proteins that undergo Type IV UPS pathways are position-specific antigen subunit alpha 1 integrin, cystic fibrosis transmembrane conductance regulator, myeloproliferative leukemia virus oncogene, and pendrin. Although we collectively refer to all Golgi-bypassing routes as UPS, individual trafficking pathways are diverse compared to the conventional pathways, and the molecular mechanisms of UPS pathways are not yet completely defined. This review summarizes the intracellular trafficking pathways of UPS cargo proteins, particularly those with transmembrane domains, and discusses the molecular machinery involved in the UPS of transmembrane proteins.
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Affiliation(s)
- Heon Yung Gee
- Department of Pharmacology, Brain Korea21 Project for Medical Sciences, Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea
| | - Jiyoon Kim
- Department of Pharmacology, Brain Korea21 Project for Medical Sciences, Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea
| | - Min Goo Lee
- Department of Pharmacology, Brain Korea21 Project for Medical Sciences, Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea.
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46
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47
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Bellucci M, De Marchis F, Pompa A. The endoplasmic reticulum is a hub to sort proteins toward unconventional traffic pathways and endosymbiotic organelles. JOURNAL OF EXPERIMENTAL BOTANY 2017; 69:7-20. [PMID: 28992342 DOI: 10.1093/jxb/erx286] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 07/24/2017] [Indexed: 05/25/2023]
Abstract
The discovery that much of the extracellular proteome in eukaryotic cells consists of proteins lacking a signal peptide, which cannot therefore enter the secretory pathway, has led to the identification of alternative protein secretion routes bypassing the Golgi apparatus. However, proteins harboring a signal peptide for translocation into the endoplasmic reticulum can also be transported along these alternative routes, which are still far from being well elucidated in terms of the molecular machineries and subcellular/intermediate compartments involved. In this review, we first try to provide a definition of all the unconventional protein secretion pathways in eukaryotic cells, as those pathways followed by proteins directed to an 'external space' bypassing the Golgi, where 'external space' refers to the extracellular space plus the lumen of the secretory route compartments and the inner space of mitochondria and plastids. Then, we discuss the role of the endoplasmic reticulum in sorting proteins toward unconventional traffic pathways in plants. In this regard, various unconventional pathways exporting proteins from the endoplasmic reticulum to the vacuole, plasma membrane, apoplast, mitochondria, and plastids are described, including the short routes followed by the proteins resident in the endoplasmic reticulum.
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Affiliation(s)
- Michele Bellucci
- Institute of Biosciences and Bioresources, Research Division of Perugia, National Research Council (CNR), Italy
| | - Francesca De Marchis
- Institute of Biosciences and Bioresources, Research Division of Perugia, National Research Council (CNR), Italy
| | - Andrea Pompa
- Institute of Biosciences and Bioresources, Research Division of Perugia, National Research Council (CNR), Italy
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Zhang K, Tan J, Su J, Liang H, Shen L, Li C, Pan G, Yang L, Cui H. Integrin β3 plays a novel role in innate immunity in silkworm, Bombyx mori. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2017; 77:307-317. [PMID: 28826989 DOI: 10.1016/j.dci.2017.08.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 08/16/2017] [Accepted: 08/17/2017] [Indexed: 06/07/2023]
Abstract
Integrins are transmembrane receptors that play essential roles in many physiological and pathological processes through cell-to-cell and cell-to-extracellular matrix (ECM) interactions. In the current study, a 2653-bp full-length cDNA of a novel integrin β subunit (designated Bmintegrin β3) was obtained from silkworm hemocytes. Bmintegrin β3 has the typical conserved structure of the integrin β family. The qRT-PCR results showed that Bmintegrin β3 was specifically expressed in the hematological system and that its expression was significantly increased after challenge with different types of PAMPs and bacteria. The recombinant Bmintegrin β3 protein displayed increased aggregation with S. aureus, suggesting that Bmintegrin β3 might directly bind to PAMPs. Interestingly, Bmintegrin β3 knockdown promoted PPO1, PPO2, BAEE, SPH78, SPH125, and SPH127 expression and accelerated the melanization process. Unexpectedly, the expression of genes related to phagocytosis, the Toll pathway, and the IMD pathway was also up-regulated after Bmintegrin β3 knockdown. Thus, Bmintegrin β3 might be a pattern recognition protein (PRP) for PAMPs and might directly bind to bacteria and enhance the phagocytosis activity of hemocytes. Moreover, Bmintegrin β3 and its ligand might negatively regulate the expression of immune-related genes through an unknown mechanism. In summary, our studies provide new insights into the immune functions of Bmintegrin β3 from the silkworm, Bombyx mori.
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Affiliation(s)
- Kui Zhang
- State Key Laboratory of Silkworm Genome Biology, The Institute of Sericulture and Systems Biology, Southwest University, Chongqing 400716, China
| | - Juan Tan
- State Key Laboratory of Silkworm Genome Biology, The Institute of Sericulture and Systems Biology, Southwest University, Chongqing 400716, China
| | - Jingjing Su
- State Key Laboratory of Silkworm Genome Biology, The Institute of Sericulture and Systems Biology, Southwest University, Chongqing 400716, China
| | - Hanghua Liang
- State Key Laboratory of Silkworm Genome Biology, The Institute of Sericulture and Systems Biology, Southwest University, Chongqing 400716, China
| | - Li Shen
- State Key Laboratory of Silkworm Genome Biology, The Institute of Sericulture and Systems Biology, Southwest University, Chongqing 400716, China
| | - Chongyang Li
- State Key Laboratory of Silkworm Genome Biology, The Institute of Sericulture and Systems Biology, Southwest University, Chongqing 400716, China
| | - Guangzhao Pan
- State Key Laboratory of Silkworm Genome Biology, The Institute of Sericulture and Systems Biology, Southwest University, Chongqing 400716, China
| | - Liqun Yang
- State Key Laboratory of Silkworm Genome Biology, The Institute of Sericulture and Systems Biology, Southwest University, Chongqing 400716, China
| | - Hongjuan Cui
- State Key Laboratory of Silkworm Genome Biology, The Institute of Sericulture and Systems Biology, Southwest University, Chongqing 400716, China.
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Abstract
Tango1 enables ER-to-Golgi trafficking of large proteins. We show here that loss of Tango1, in addition to disrupting protein secretion and ER/Golgi morphology, causes ER stress and defects in cell shape. We find that the previously observed dependence of smaller cargos on Tango1 is a secondary effect. If large cargos like Dumpy, which we identify as a Tango1 cargo, are removed from the cell, nonbulky proteins reenter the secretory pathway. Removal of blocking cargo also restores cell morphology and attenuates the ER-stress response. Thus, failures in the secretion of nonbulky proteins, ER stress, and defective cell morphology are secondary consequences of bulky cargo retention. By contrast, ER/Golgi defects in Tango1-depleted cells persist in the absence of bulky cargo, showing that they are due to a secretion-independent function of Tango1. Therefore, maintenance of ER/Golgi architecture and bulky cargo transport are the primary functions for Tango1.
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50
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A Mechanism Coupling Systemic Energy Sensing to Adipokine Secretion. Dev Cell 2017; 43:83-98.e6. [PMID: 29017032 DOI: 10.1016/j.devcel.2017.09.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 07/18/2017] [Accepted: 09/11/2017] [Indexed: 01/13/2023]
Abstract
Adipocytes sense systemic nutrient status and systemically communicate this information by releasing adipokines. The mechanisms that couple nutritional state to adipokine release are unknown. Here, we investigated how Unpaired 2 (Upd2), a structural and functional ortholog of the primary human adipokine leptin, is released from Drosophila fat cells. We find that Golgi reassembly stacking protein (GRASP), an unconventional secretion pathway component, is required for Upd2 secretion. In nutrient-rich fat cells, GRASP clusters in close proximity to the apical side of lipid droplets (LDs). During nutrient deprivation, glucagon-mediated increase in calcium (Ca2+) levels, via calmodulin kinase II (CaMKII) phosphorylation, inhibits proximal GRASP localization to LDs. Using a heterologous cell system, we show that human leptin secretion is also regulated by Ca2+ and CaMKII. In summary, we describe a mechanism by which increased cytosolic Ca2+ negatively regulates adipokine secretion and have uncovered an evolutionarily conserved molecular link between intracellular Ca2+ levels and energy homeostasis.
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