1
|
Kochlamazashvili G, Swaminathan A, Stumpf A, Kumar A, Posor Y, Schmitz D, Haucke V, Kuijpers M. Neuronal autophagy controls excitability via ryanodine receptor-mediated regulation of calcium-activated potassium channel function. Proc Natl Acad Sci U S A 2025; 122:e2413651122. [PMID: 40267139 PMCID: PMC12054804 DOI: 10.1073/pnas.2413651122] [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: 07/08/2024] [Accepted: 03/21/2025] [Indexed: 04/25/2025] Open
Abstract
Glutamate-mediated neuronal hyperexcitation plays a causative role in eliciting seizures and promoting epileptogenesis. Recent data suggest that altered autophagy can contribute to the occurrence of epilepsy. We examined the role of autophagy in neuronal physiology by generating knockout mice conditionally lacking the essential autophagy protein ATG5 in glutamatergic neurons. We demonstrate that conditional genetic blockade of neuronal autophagy results in action potential narrowing, axonal hyperexcitability, and an increase in kainate-induced epileptiform bursts ex vivo, indicative of a lower threshold for the induction of epileptic seizures. Neuronal hyperexcitability in hippocampal slices from conditional ATG5 knockout mice is due to elevated activity of the large conductance calcium-activated potassium channel BKCa downstream of calcium influx via the endoplasmic reticulum (ER)-localized calcium channel ryanodine receptor (RYR). Consistently, pharmacological blockade of RYR or BKCa function rescued hyperexcitability and reduced the frequency of kainate-induced epileptiform bursts in ATG5 cKO brain slices. Our findings reveal a physiological role for neuronal autophagy in the regulation of neuronal excitability via the control of RYR-mediated calcium release, and thereby, calcium-activated potassium channel function in the mammalian brain.
Collapse
Affiliation(s)
- Gaga Kochlamazashvili
- Molecular Pharmacology and Cell Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin13125, Germany
| | - Aarti Swaminathan
- NeuroCure Cluster of Excellence, Charité Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin10117, Germany
| | - Alexander Stumpf
- NeuroCure Cluster of Excellence, Charité Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin10117, Germany
| | - Amit Kumar
- NeuroCure Cluster of Excellence, Charité Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin10117, Germany
| | - York Posor
- Molecular Pharmacology and Cell Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin13125, Germany
| | - Dietmar Schmitz
- NeuroCure Cluster of Excellence, Charité Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin10117, Germany
| | - Volker Haucke
- Molecular Pharmacology and Cell Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin13125, Germany
- NeuroCure Cluster of Excellence, Charité Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin10117, Germany
- Faculty of Biology, Chemistry, Pharmacy, Freie Universität Berlin, Berlin14195, Germany
| | - Marijn Kuijpers
- Molecular Pharmacology and Cell Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin13125, Germany
- Donders Institute for Brain, Cognition and Behaviour and Faculty of Science, Radboud University, Nijmegen6525AJ, The Netherlands
| |
Collapse
|
2
|
Jing W, Qingqing C, Xia Y, Ningxiang Q, Demei X, Xuefeng W, Ming A, Xi P, Liang W. Inhibiting SNX14 Alleviates Epileptic Seizures by Regulating GluA2 Degradation via the Lysosomal Pathway. Mol Neurobiol 2025:10.1007/s12035-025-04945-y. [PMID: 40237949 DOI: 10.1007/s12035-025-04945-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2024] [Accepted: 04/11/2025] [Indexed: 04/18/2025]
Abstract
Epilepsy is a common chronic neurological condition, and temporal lobe epilepsy (TLE) is the most common form of refractory epilepsy. However, the underlying causes of TLE remain unclear. Our initial findings revealed that the expression of sorting nexin 14 (SNX14), which is a member of the sorting nexin protein family, was significantly upregulated in brain tissues from both patients with TLE and mouse models of TLE. Moreover, modulation of SNX14 expression in the hippocampus of mice demonstrated that SNX14 downregulation significantly decreased the susceptibility to and severity of seizures, whereas SNX14 overexpression exerted the opposite effects. Mechanistically, we revealed that GluA2, which is a subunit of the α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) receptor, was a downstream target of SNX14. Further studies indicated that SNX14 modulated GluA2 protein levels by regulating GluA2 degradation via the lysosomal pathway, which in turn influenced glutamatergic synaptic transmission. In conclusion, our findings suggest that the SNX14-GluA2 pathway could be a promising target for the development of novel treatments for epilepsy.
Collapse
Affiliation(s)
- Wang Jing
- Department of Neurology, Chongqing Key Laboratory of Major Neurological and Mental Disorders, Chongqing Key Laboratory of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Cao Qingqing
- Department of Neurology, Bishan Hospital of Chongqing Medical University, Bishan Hospital of Chongqing, Chongqing, China
| | - Yan Xia
- Department of Neurology, Chongqing Key Laboratory of Major Neurological and Mental Disorders, Chongqing Key Laboratory of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Qin Ningxiang
- Department of Neurology, Chongqing Key Laboratory of Major Neurological and Mental Disorders, Chongqing Key Laboratory of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Xu Demei
- Department of Neurology, Chongqing Key Laboratory of Major Neurological and Mental Disorders, Chongqing Key Laboratory of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Wang Xuefeng
- Department of Neurology, Chongqing Key Laboratory of Major Neurological and Mental Disorders, Chongqing Key Laboratory of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Ai Ming
- Department of Psychiatry, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Peng Xi
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China.
| | - Wang Liang
- Department of Neurology, Chongqing Key Laboratory of Major Neurological and Mental Disorders, Chongqing Key Laboratory of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
- Key Laboratory of Major Brain Disease and Aging Research (Ministry of Education), Chongqing Medical University, Chongqing, China.
| |
Collapse
|
3
|
Lazzeri G, Lenzi P, Signorini G, Raffaelli S, Giammattei E, Natale G, Ruffoli R, Fornai F, Ferrucci M. Retinoic Acid Promotes Neuronal Differentiation While Increasing Proteins and Organelles Related to Autophagy. Int J Mol Sci 2025; 26:1691. [PMID: 40004155 PMCID: PMC11855701 DOI: 10.3390/ijms26041691] [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: 12/30/2024] [Revised: 02/12/2025] [Accepted: 02/15/2025] [Indexed: 02/27/2025] Open
Abstract
Retinoic acid (RA) is commonly used to differentiate SH-SY5Y neuroblastoma cells. This effect is sustained by a specific modulation of gene transcription, leading to marked changes in cellular proteins. In this scenario, autophagy may be pivotal in balancing protein synthesis and degradation. The present study analyzes whether some autophagy-related proteins and organelles are modified during RA-induced differentiation of SH-SY5Y cells. RA-induced effects were compared to those induced by starvation. SH-SY5Y cells were treated with a single dose of 10 µM RA or grown in starvation, for 3 days or 7 days. After treatments, cells were analyzed at light microscopy and transmission electron microscopy to assess cell morphology and immunostaining for specific markers (nestin, βIII-tubulin, NeuN) and some autophagy-related proteins (Beclin 1, LC3). We found that both RA and starvation differentiate SH-SY5Y cells. Specifically, cell differentiation was concomitant with an increase in autophagy proteins and autophagy-related organelles. However, the effects of a single dose of 10 μM RA persist for at least 7 days, while prolonged starvation produces cell degeneration and cell loss. Remarkably, the effects of RA are modulated in the presence of autophagy inhibitors or stimulators. The present data indicate that RA-induced differentiation is concomitant with an increased autophagy.
Collapse
Affiliation(s)
- Gloria Lazzeri
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy; (G.L.); (P.L.); (G.S.); (S.R.); (E.G.); (G.N.); (R.R.); (F.F.)
| | - Paola Lenzi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy; (G.L.); (P.L.); (G.S.); (S.R.); (E.G.); (G.N.); (R.R.); (F.F.)
| | - Giulia Signorini
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy; (G.L.); (P.L.); (G.S.); (S.R.); (E.G.); (G.N.); (R.R.); (F.F.)
| | - Sara Raffaelli
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy; (G.L.); (P.L.); (G.S.); (S.R.); (E.G.); (G.N.); (R.R.); (F.F.)
| | - Elisa Giammattei
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy; (G.L.); (P.L.); (G.S.); (S.R.); (E.G.); (G.N.); (R.R.); (F.F.)
| | - Gianfranco Natale
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy; (G.L.); (P.L.); (G.S.); (S.R.); (E.G.); (G.N.); (R.R.); (F.F.)
| | - Riccardo Ruffoli
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy; (G.L.); (P.L.); (G.S.); (S.R.); (E.G.); (G.N.); (R.R.); (F.F.)
| | - Francesco Fornai
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy; (G.L.); (P.L.); (G.S.); (S.R.); (E.G.); (G.N.); (R.R.); (F.F.)
- IRCCS-Istituto di Ricovero e Cura a Carattere Scientifico, Neuromed, 86077 Pozzilli, Italy
| | - Michela Ferrucci
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy; (G.L.); (P.L.); (G.S.); (S.R.); (E.G.); (G.N.); (R.R.); (F.F.)
| |
Collapse
|
4
|
Carrillo F, Ghirimoldi M, Fortunato G, Palomba NP, Ianiro L, De Giorgis V, Khoso S, Giloni T, Pietracupa S, Modugno N, Barberis E, Manfredi M, Esposito T. Multiomics approach identifies dysregulated lipidomic and proteomic networks in Parkinson's disease patients mutated in TMEM175. NPJ Parkinsons Dis 2025; 11:23. [PMID: 39856101 PMCID: PMC11760379 DOI: 10.1038/s41531-024-00853-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Accepted: 12/09/2024] [Indexed: 01/27/2025] Open
Abstract
Parkinson's disease (PD) represents one of the most frequent neurodegenerative disorders for which clinically useful biomarkers remain to be identified and validated. Here, we adopted an untargeted omics approach to disclose lipidomic, metabolomic and proteomic alterations in plasma and in dermal fibroblasts of PD patients carrying mutations in TMEM175 gene. We revealed a wide dysregulation of lysosome, autophagy, and mitochondrial pathways in these patients, supporting a role of this channel in regulating these cellular processes. The most significant altered lipid classes were Fatty acyls, Glycerophospholipids and Phosphosphingolipids. The plasma level of Phosphatidylcholines (PC) and Phosphatidylinositol (PI) 34:1 significantly correlated with an earlier age at onset of the disease in TMEM175 patients (p = 0.008; p = 0.006). In plasma we also observed altered amino acids metabolic pathways in PD patients. We highlighted that increased level of L-glutamate strongly correlated (p < 0.001) with the severity of motor and non-motor symptoms in PD_TMEM175 patients. In dermal fibroblasts, we disclosed alterations of proteins involved in lipids biosynthesis (PAG15, PP4P1, GALC, FYV1, PIGO, PGPS1, PLPP1), in the insulin pathway (IGF2R), in mitochondrial metabolism (ACD10, ACD11, ACADS) and autophagy (RAB7L). Interestingly, we quantified 43 lysosomal or lysosomal-related proteins, which were differentially modulated between TMEM175 patients and controls. Integrative correlation analysis of proteome and lipidome of PD_TMEM175 cellular models identified a strong positive correlation of 13 proteins involved in biosynthetic processes with PC and Ceramides. Altogether, these data provide novel insights into the molecular and metabolic alterations underlying TMEM175 mutations and may be relevant for PD prediction, diagnosis and treatment.
Collapse
Affiliation(s)
- Federica Carrillo
- Institute of Genetics and Biophysics "Adriano Buzzati-Traverso", National Research Council, Naples, Italy
| | - Marco Ghirimoldi
- Biological Mass Spectrometry Lab, Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy
| | - Giorgio Fortunato
- Institute of Genetics and Biophysics "Adriano Buzzati-Traverso", National Research Council, Naples, Italy
| | | | | | - Veronica De Giorgis
- Biological Mass Spectrometry Lab, Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy
| | - Shahzaib Khoso
- Biological Mass Spectrometry Lab, Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy
- Center for Translational Research on Autoimmune and Allergic Diseases, University of Piemonte Orientale, Novara, Italy
| | | | - Sara Pietracupa
- IRCCS INM Neuromed, Pozzilli, Italy
- Department of Human Neuroscience, Sapienza University of Rome, Piazzale Aldo Moro, Italy
| | | | - Elettra Barberis
- Center for Translational Research on Autoimmune and Allergic Diseases, University of Piemonte Orientale, Novara, Italy
- Department of Sciences and Technological Innovation, University of Piemonte Orientale, Alessandria, Italy
| | - Marcello Manfredi
- Biological Mass Spectrometry Lab, Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy
- IRCCS Policlinico San Donato, Institute of Molecular and Translational Cardiology, Milan, Italy
| | - Teresa Esposito
- Institute of Genetics and Biophysics "Adriano Buzzati-Traverso", National Research Council, Naples, Italy.
- IRCCS INM Neuromed, Pozzilli, Italy.
| |
Collapse
|
5
|
Namikawa K, Pose-Méndez S, Köster RW. Genetic modeling of degenerative diseases and mechanisms of neuronal regeneration in the zebrafish cerebellum. Cell Mol Life Sci 2024; 82:26. [PMID: 39725709 DOI: 10.1007/s00018-024-05538-z] [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: 07/24/2024] [Revised: 10/11/2024] [Accepted: 12/01/2024] [Indexed: 12/28/2024]
Abstract
The cerebellum is a highly conserved brain compartment of vertebrates. Genetic diseases of the human cerebellum often lead to degeneration of the principal neuron, the Purkinje cell, resulting in locomotive deficits and socio-emotional impairments. Due to its relatively simple but highly conserved neuroanatomy and circuitry, these human diseases can be modeled well in vertebrates amenable for genetic manipulation. In the recent years, cerebellar research in zebrafish has contributed to understanding cerebellum development and function, since zebrafish larvae are not only molecularly tractable, but also accessible for high resolution in vivo imaging due to the transparency of the larvae and the ease of access to the zebrafish cerebellar cortex for microscopy approaches. Therefore, zebrafish is increasingly used for genetic modeling of human cerebellar neurodegenerative diseases and in particular of different types of Spinocerebellar Ataxias (SCAs). These models are well suited to address the underlying pathogenic mechanisms by means of in vivo cell biological studies. Furthermore, accompanying circuitry characterizations, physiological studies and behavioral analysis allow for unraveling molecular, structural and functional relationships. Moreover, unlike in mammals, zebrafish possess an astonishing ability to regenerate neuronal populations and their functional circuitry in the central nervous system including the cerebellum. Understanding the cellular and molecular processes of these regenerative processes could well serve to counteract acute and chronic loss of neurons in humans. Based on the high evolutionary conservation of the cerebellum these regeneration studies in zebrafish promise to open therapeutic avenues for counteracting cerebellar neuronal degeneration. The current review aims to provide an overview over currently existing genetic models of human cerebellar neurodegenerative diseases in zebrafish as well as neuroregeneration studies using the zebrafish cerebellum. Due to this solid foundation in cerebellar disease modeling and neuronal regeneration analysis, the zebrafish promises to become a popular model organism for both unraveling pathogenic mechanisms of human cerebellar diseases and providing entry points for therapeutic neuronal regeneration approaches.
Collapse
Affiliation(s)
- Kazuhiko Namikawa
- Cellular and Molecular Neurobiology, Technische Universität Braunschweig, 38106, Braunschweig, Germany
| | - Sol Pose-Méndez
- Cellular and Molecular Neurobiology, Technische Universität Braunschweig, 38106, Braunschweig, Germany
| | - Reinhard W Köster
- Cellular and Molecular Neurobiology, Technische Universität Braunschweig, 38106, Braunschweig, Germany.
| |
Collapse
|
6
|
Lv S, Jiang H, Yu L, Zhang Y, Sun L, Xu J. SNX14 inhibits autophagy via the PI3K/AKT/mTOR signaling cascade in breast cancer cells. J Mol Histol 2024; 55:391-401. [PMID: 38869753 DOI: 10.1007/s10735-024-10209-1] [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: 09/06/2023] [Accepted: 06/01/2024] [Indexed: 06/14/2024]
Abstract
BACKGROUND Sorting nexin 14 (SNX14) is a member of the sorting junction protein family. Its specific roles in cancer development remain unclear. Therefore, in this study, we aimed to determine the effects and underlying mechanisms of SNX14 on autophagy of breast cancer cells to aid in the therapeutic treatment of breast cancer. METHODS In this study, we performed in vitro experiments to determine the effect of SNX14 on breast cancer cell growth. Moreover, we used an MCF7 breast cancer tumor-bearing mouse model to confirm the effect of SNX14 on tumor cell growth in vivo. We also performed western blotting and quantitative polymerase chain reaction to identify the mechanism by which SNX14 affects breast cancer MCF7 cells. RESULTS We found that SNX14 regulated the onset and progression of breast cancer by promoting the proliferation and inhibiting the autophagy of MCF7 breast cancer cells. In vivo experiments further confirmed that SNX14 knockdown inhibited the tumorigenicity and inhibited the growth of tumor cells in tumor tissues of nude mice. In addition, western blotting analysis revealed that SNX14 modulate the autophagy of MCF7 breast cancer cells via the phosphoinositide 3-kinase/protein kinase B/mechanistic target of rapamycin kinase signaling pathway. CONCLUSION Our findings indicate that SNX14 is an essential tumor-promoting factor in the development of breast cancer.
Collapse
Affiliation(s)
- Sha Lv
- Department of Pharmacy, Zhejiang Hospital, Hangzhou, 310013, China
| | - Hongyan Jiang
- Department of Pharmacy, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, China
| | - Lingyan Yu
- Department of Pharmacy, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, China
| | - Yafei Zhang
- Department of Nuclear Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China
| | - Liangliang Sun
- Department of Pharmacy, Zhejiang Hospital, Hangzhou, 310013, China
| | - Junjun Xu
- Department of Pharmacy, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, China.
| |
Collapse
|
7
|
Bandyopadhyay S, Adebayo D, Obaseki E, Hariri H. Lysosomal membrane contact sites: Integrative hubs for cellular communication and homeostasis. CURRENT TOPICS IN MEMBRANES 2024; 93:85-116. [PMID: 39181579 DOI: 10.1016/bs.ctm.2024.07.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/27/2024]
Abstract
Lysosomes are more than just cellular recycling bins; they play a crucial role in regulating key cellular functions. Proper lysosomal function is essential for growth pathway regulation, cell proliferation, and metabolic homeostasis. Impaired lysosomal function is associated with lipid storage disorders and neurodegenerative diseases. Lysosomes form extensive and dynamic close contacts with the membranes of other organelles, including the endoplasmic reticulum, mitochondria, peroxisomes, and lipid droplets. These membrane contacts sites (MCSs) are vital for many lysosomal functions. In this chapter, we will explore lysosomal MCSs focusing on the machinery that mediates these contacts, how they are regulated, and their functional implications on physiology and pathology.
Collapse
Affiliation(s)
- Sumit Bandyopadhyay
- Department of Biological Sciences, Wayne State University, Detroit, MI, United States
| | - Daniel Adebayo
- Department of Biological Sciences, Wayne State University, Detroit, MI, United States
| | - Eseiwi Obaseki
- Department of Biological Sciences, Wayne State University, Detroit, MI, United States
| | - Hanaa Hariri
- Department of Biological Sciences, Wayne State University, Detroit, MI, United States.
| |
Collapse
|
8
|
Zhou Y, Sanchez VB, Xu P, Roule T, Flores-Mendez M, Ciesielski B, Yoo D, Teshome H, Jimenez T, Liu S, Henne M, O’Brien T, He Y, Mesaros C, Akizu N. Altered lipid homeostasis is associated with cerebellar neurodegeneration in SNX14 deficiency. JCI Insight 2024; 9:e168594. [PMID: 38625743 PMCID: PMC11141923 DOI: 10.1172/jci.insight.168594] [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: 01/05/2023] [Accepted: 04/05/2024] [Indexed: 04/17/2024] Open
Abstract
Dysregulated lipid homeostasis is emerging as a potential cause of neurodegenerative disorders. However, evidence of errors in lipid homeostasis as a pathogenic mechanism of neurodegeneration remains limited. Here, we show that cerebellar neurodegeneration caused by Sorting Nexin 14 (SNX14) deficiency is associated with lipid homeostasis defects. Recent studies indicate that SNX14 is an interorganelle lipid transfer protein that regulates lipid transport, lipid droplet (LD) biogenesis, and fatty acid desaturation, suggesting that human SNX14 deficiency belongs to an expanding class of cerebellar neurodegenerative disorders caused by altered cellular lipid homeostasis. To test this hypothesis, we generated a mouse model that recapitulates human SNX14 deficiency at a genetic and phenotypic level. We demonstrate that cerebellar Purkinje cells (PCs) are selectively vulnerable to SNX14 deficiency while forebrain regions preserve their neuronal content. Ultrastructure and lipidomic studies reveal widespread lipid storage and metabolism defects in SNX14-deficient mice. However, predegenerating SNX14-deficient cerebella show a unique accumulation of acylcarnitines and depletion of triglycerides. Furthermore, defects in LD content and telolysosome enlargement in predegenerating PCs suggest lipotoxicity as a pathogenic mechanism of SNX14 deficiency. Our work shows a selective cerebellar vulnerability to altered lipid homeostasis and provides a mouse model for future therapeutic studies.
Collapse
Affiliation(s)
- Yijing Zhou
- Perelman Center for Cellular and Molecular Therapeutics, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Pathology and Laboratory Medicine and
| | - Vanessa B. Sanchez
- Perelman Center for Cellular and Molecular Therapeutics, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Pathology and Laboratory Medicine and
| | - Peining Xu
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Thomas Roule
- Perelman Center for Cellular and Molecular Therapeutics, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Pathology and Laboratory Medicine and
| | - Marco Flores-Mendez
- Perelman Center for Cellular and Molecular Therapeutics, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Pathology and Laboratory Medicine and
| | - Brianna Ciesielski
- Institute for Translational Medicine and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Donna Yoo
- Perelman Center for Cellular and Molecular Therapeutics, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Pathology and Laboratory Medicine and
| | - Hiab Teshome
- Perelman Center for Cellular and Molecular Therapeutics, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Pathology and Laboratory Medicine and
| | - Teresa Jimenez
- Perelman Center for Cellular and Molecular Therapeutics, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Pathology and Laboratory Medicine and
| | - Shibo Liu
- The Graduate Center of the City University of New York, Advanced Science Research Center, New York, New York, USA
| | - Mike Henne
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Tim O’Brien
- Institute for Translational Medicine and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ye He
- The Graduate Center of the City University of New York, Advanced Science Research Center, New York, New York, USA
- Ph.D. Program in Biology, The Graduate Center of the City University of New York, New York, New York, USA
| | - Clementina Mesaros
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Naiara Akizu
- Perelman Center for Cellular and Molecular Therapeutics, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Pathology and Laboratory Medicine and
| |
Collapse
|
9
|
Shao Y, Yang S, Li J, Cheng L, Kang J, Liu J, Ma J, Duan J, Zhang Y. Compound heterozygous mutation of the SNX14 gene causes autosomal recessive spinocerebellar ataxia 20. Front Genet 2024; 15:1379366. [PMID: 38655056 PMCID: PMC11035801 DOI: 10.3389/fgene.2024.1379366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Accepted: 03/20/2024] [Indexed: 04/26/2024] Open
Abstract
Objective: The article aims to provide genetic counseling to a family with two children who were experiencing growth and developmental delays. Methods: Clinical information of the proband was collected. Peripheral blood was collected from core family members to identify the initial reason for growth and developmental delays by whole exome sequencing (WES) and Sanger sequencing. To ascertain the consequences of the newly discovered variants, details of the variants detected were analyzed by bioinformatic tools. Furthermore, we performed in vitro experimentation targeting SNX14 gene expression to confirm whether the variants could alter the expression of SNX14. Results: The proband had prenatal ultrasound findings that included flattened frontal bones, increased interocular distance, widened bilateral cerebral sulci, and shortened long bones, which resulted in subsequent postnatal developmental delays. The older sister also displayed growth developmental delays and poor muscle tone. WES identified compound heterozygous variants of c.712A>T (p.Arg238Ter) and .2744A>T (p.Gln915Leu) in the SNX14 gene in these two children. Both are novel missense variant that originates from the father and mother, respectively. Sanger sequencing confirmed this result. Following the guideline of the American College of Medical Genetics and Genomics (ACMG), the SNX14 c.712A>T (p.Arg238Ter) variant was predicted to be pathogenic (P), while the SNX14 c.2744A>T (p.Gln915Leu) variant was predicted to be a variant of uncertain significance (VUS). The structural analysis revealed that the c.2744A>T (p.Gln915Leu) variant may impact the stability of the SNX14 protein. In vitro experiments demonstrated that both variants reduced SNX14 expression. Conclusion: The SNX14 gene c.712A>T (p.Arg238Ter) and c.2744A>T (p.Gln915Leu) were identified as the genetic causes of growth and developmental delay in two affected children. This conclusion was based on the clinical presentations of the children, structural analysis of the mutant protein, and in vitro experimental validation. This discovery expands the range of SNX14 gene variants and provides a foundation for genetic counseling and guidance for future pregnancies in the affected children's families.
Collapse
Affiliation(s)
- Yuqi Shao
- Department of Obstetrics, Zhongnan Hospital of Wuhan University, Wuhan, China
- Hubei Clinical Research Center for Prenatal Diagnosis and Birth Health, Wuhan, China
| | - Saisai Yang
- Department of Obstetrics, Zhongnan Hospital of Wuhan University, Wuhan, China
- Hubei Clinical Research Center for Prenatal Diagnosis and Birth Health, Wuhan, China
| | - Jiafu Li
- Department of Obstetrics, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Lin Cheng
- Department of Obstetrics, Zhongnan Hospital of Wuhan University, Wuhan, China
- Hubei Clinical Research Center for Prenatal Diagnosis and Birth Health, Wuhan, China
| | - Jiawei Kang
- Department of Obstetrics, Zhongnan Hospital of Wuhan University, Wuhan, China
- Hubei Clinical Research Center for Prenatal Diagnosis and Birth Health, Wuhan, China
| | - Juan Liu
- Department of Obstetrics, Zhongnan Hospital of Wuhan University, Wuhan, China
- Hubei Clinical Research Center for Prenatal Diagnosis and Birth Health, Wuhan, China
| | - Jianhong Ma
- Department of Obstetrics, Zhongnan Hospital of Wuhan University, Wuhan, China
- Hubei Clinical Research Center for Prenatal Diagnosis and Birth Health, Wuhan, China
| | - Jie Duan
- Department of Obstetrics, Zhongnan Hospital of Wuhan University, Wuhan, China
- Hubei Clinical Research Center for Prenatal Diagnosis and Birth Health, Wuhan, China
| | - Yuanzhen Zhang
- Department of Obstetrics, Zhongnan Hospital of Wuhan University, Wuhan, China
- Hubei Clinical Research Center for Prenatal Diagnosis and Birth Health, Wuhan, China
| |
Collapse
|
10
|
Liénard C, Pintart A, Bomont P. Neuronal Autophagy: Regulations and Implications in Health and Disease. Cells 2024; 13:103. [PMID: 38201307 PMCID: PMC10778363 DOI: 10.3390/cells13010103] [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: 10/26/2023] [Revised: 12/02/2023] [Accepted: 12/27/2023] [Indexed: 01/12/2024] Open
Abstract
Autophagy is a major degradative pathway that plays a key role in sustaining cell homeostasis, integrity, and physiological functions. Macroautophagy, which ensures the clearance of cytoplasmic components engulfed in a double-membrane autophagosome that fuses with lysosomes, is orchestrated by a complex cascade of events. Autophagy has a particularly strong impact on the nervous system, and mutations in core components cause numerous neurological diseases. We first review the regulation of autophagy, from autophagosome biogenesis to lysosomal degradation and associated neurodevelopmental/neurodegenerative disorders. We then describe how this process is specifically regulated in the axon and in the somatodendritic compartment and how it is altered in diseases. In particular, we present the neuronal specificities of autophagy, with the spatial control of autophagosome biogenesis, the close relationship of maturation with axonal transport, and the regulation by synaptic activity. Finally, we discuss the physiological functions of autophagy in the nervous system, during development and in adulthood.
Collapse
Affiliation(s)
- Caroline Liénard
- NeuroMyoGene Institute—PGNM, CNRS UMR 5261—INSERM U1315, University of Claude Bernard Lyon 1, 69008 Lyon, France; (C.L.); (A.P.)
- CHU Montpellier, University of Montpellier, 34295 Montpellier, France
| | - Alexandre Pintart
- NeuroMyoGene Institute—PGNM, CNRS UMR 5261—INSERM U1315, University of Claude Bernard Lyon 1, 69008 Lyon, France; (C.L.); (A.P.)
| | - Pascale Bomont
- NeuroMyoGene Institute—PGNM, CNRS UMR 5261—INSERM U1315, University of Claude Bernard Lyon 1, 69008 Lyon, France; (C.L.); (A.P.)
| |
Collapse
|
11
|
Lewerissa EI, Nadif Kasri N, Linda K. Epigenetic regulation of autophagy-related genes: Implications for neurodevelopmental disorders. Autophagy 2024; 20:15-28. [PMID: 37674294 PMCID: PMC10761153 DOI: 10.1080/15548627.2023.2250217] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 08/11/2023] [Indexed: 09/08/2023] Open
Abstract
Macroautophagy/autophagy is an evolutionarily highly conserved catabolic process that is important for the clearance of cytosolic contents to maintain cellular homeostasis and survival. Recent findings point toward a critical role for autophagy in brain function, not only by preserving neuronal health, but especially by controlling different aspects of neuronal development and functioning. In line with this, mutations in autophagy-related genes are linked to various key characteristics and symptoms of neurodevelopmental disorders (NDDs), including autism, micro-/macrocephaly, and epilepsy. However, the group of NDDs caused by mutations in autophagy-related genes is relatively small. A significant proportion of NDDs are associated with mutations in genes encoding epigenetic regulatory proteins that modulate gene expression, so-called chromatinopathies. Intriguingly, several of the NDD-linked chromatinopathy genes have been shown to regulate autophagy-related genes, albeit in non-neuronal contexts. From these studies it becomes evident that tight transcriptional regulation of autophagy-related genes is crucial to control autophagic activity. This opens the exciting possibility that aberrant autophagic regulation might underly nervous system impairments in NDDs with disturbed epigenetic regulation. We here summarize NDD-related chromatinopathy genes that are known to regulate transcriptional regulation of autophagy-related genes. Thereby, we want to highlight autophagy as a candidate key hub mechanism in NDD-related chromatinopathies.Abbreviations: ADNP: activity dependent neuroprotector homeobox; ASD: autism spectrum disorder; ATG: AutTophaGy related; CpG: cytosine-guanine dinucleotide; DNMT: DNA methyltransferase; EHMT: euchromatic histone lysine methyltransferase; EP300: E1A binding protein p300; EZH2: enhancer of zeste 2 polycomb repressive complex 2 subunit; H3K4me3: histone 3 lysine 4 trimethylation; H3K9me1/2/3: histone 3 lysine 9 mono-, di-, or trimethylation; H3K27me2/3: histone 3 lysine 27 di-, or trimethylation; hiPSCs: human induced pluripotent stem cells; HSP: hereditary spastic paraplegia; ID: intellectual disability; KANSL1: KAT8 regulatory NSL complex subunit 1; KAT8: lysine acetyltransferase 8; KDM1A/LSD1: lysine demethylase 1A; MAP1LC3B: microtubule associated protein 1 light chain 3 beta; MTOR: mechanistic target of rapamycin kinase; MTORC1: mechanistic target of rapamycin complex 1; NDD: neurodevelopmental disorder; PHF8: PHD finger protein 8; PHF8-XLID: PHF8-X linked intellectual disability syndrome; PTM: post-translational modification; SESN2: sestrin 2; YY1: YY1 transcription factor; YY1AP1: YY1 associated protein 1.
Collapse
Affiliation(s)
- Elly I. Lewerissa
- Department of Human Genetics, Radboudumc, Donders Institute for Brain, Cognition, and Behavior, Nijmegen, Gelderland, The Netherlands
| | - Nael Nadif Kasri
- Department of Human Genetics, Radboudumc, Donders Institute for Brain, Cognition, and Behavior, Nijmegen, Gelderland, The Netherlands
- Department of Cognitive Neuroscience, Radboudumc, Donders Institute for Brain, Cognition and Behavior, Nijmegen, Gelderland, The Netherlands
| | - Katrin Linda
- Department of Human Genetics, Radboudumc, Donders Institute for Brain, Cognition, and Behavior, Nijmegen, Gelderland, The Netherlands
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Flemish Brabant, Belgium
- Department of Neurosciences, KU Leuven, Leuven Brain Institute, Leuven, Flemish Brabant, Belgium
| |
Collapse
|
12
|
Cook AA, Leung TCS, Rice M, Nachman M, Zadigue-Dube É, Watt AJ. Endosomal dysfunction contributes to cerebellar deficits in spinocerebellar ataxia type 6. eLife 2023; 12:RP90510. [PMID: 38084749 PMCID: PMC10715727 DOI: 10.7554/elife.90510] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2023] Open
Abstract
Spinocerebellar ataxia type 6 (SCA6) is a rare disease that is characterized by cerebellar dysfunction. Patients have progressive motor coordination impairment, and postmortem brain tissue reveals degeneration of cerebellar Purkinje cells and a reduced level of cerebellar brain-derived neurotrophic factor (BDNF). However, the pathophysiological changes underlying SCA6 are not fully understood. We carried out RNA-sequencing of cerebellar vermis tissue in a mouse model of SCA6, which revealed widespread dysregulation of genes associated with the endo-lysosomal system. Since disruption to endosomes or lysosomes could contribute to cellular deficits, we examined the endo-lysosomal system in SCA6. We identified alterations in multiple endosomal compartments in the Purkinje cells of SCA6 mice. Early endosomes were enlarged, while the size of the late endosome compartment was reduced. We also found evidence for impaired trafficking of cargo to the lysosomes. As the proper functioning of the endo-lysosomal system is crucial for the sorting and trafficking of signaling molecules, we wondered whether these changes could contribute to previously identified deficits in signaling by BDNF and its receptor tropomyosin kinase B (TrkB) in SCA6. Indeed, we found that the enlarged early endosomes in SCA6 mice accumulated both BDNF and TrkB. Furthermore, TrkB recycling to the cell membrane in recycling endosomes was reduced, and the late endosome transport of BDNF for degradation was impaired. Therefore, mis-trafficking due to aberrant endo-lysosomal transport and function could contribute to SCA6 pathophysiology through alterations to BDNF-TrkB signaling, as well as mishandling of other signaling molecules. Deficits in early endosomes and BDNF localization were rescued by chronic administration of a TrkB agonist, 7,8-dihydroxyflavone, that we have previously shown restores motor coordination and cerebellar TrkB expression. The endo-lysosomal system is thus both a novel locus of pathophysiology in SCA6 and a promising therapeutic target.
Collapse
Affiliation(s)
- Anna A Cook
- Biology Department, McGill UniversityMontrealCanada
| | | | - Max Rice
- Biology Department, McGill UniversityMontrealCanada
- Department of Biological Sciences, Columbia UniversityNew YorkUnited States
| | - Maya Nachman
- Biology Department, McGill UniversityMontrealCanada
| | | | | |
Collapse
|
13
|
Maruzs T, Feil-Börcsök D, Lakatos E, Juhász G, Blastyák A, Hargitai D, Jean S, Lőrincz P, Juhász G. Interaction of the sorting nexin 25 homologue Snazarus with Rab11 balances endocytic and secretory transport and maintains the ultrafiltration diaphragm in nephrocytes. Mol Biol Cell 2023; 34:ar87. [PMID: 37314856 PMCID: PMC10398886 DOI: 10.1091/mbc.e22-09-0421] [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: 09/19/2022] [Revised: 06/05/2023] [Accepted: 06/06/2023] [Indexed: 06/15/2023] Open
Abstract
Proper balance of exocytosis and endocytosis is important for the maintenance of plasma membrane lipid and protein homeostasis. This is especially critical in human podocytes and the podocyte-like Drosophila nephrocytes that both use a delicate diaphragm system with evolutionarily conserved components for ultrafiltration. Here, we show that the sorting nexin 25 homologue Snazarus (Snz) binds to Rab11 and localizes to Rab11-positive recycling endosomes in Drosophila nephrocytes, unlike in fat cells where it is present in plasma membrane/lipid droplet/endoplasmic reticulum contact sites. Loss of Snz leads to redistribution of Rab11 vesicles from the cell periphery and increases endocytic activity in nephrocytes. These changes are accompanied by defects in diaphragm protein distribution that resemble those seen in Rab11 gain-of-function cells. Of note, co-overexpression of Snz rescues diaphragm defects in Rab11 overexpressing cells, whereas snz knockdown in Rab11 overexpressing nephrocytes or simultaneous knockdown of snz and tbc1d8b encoding a Rab11 GTPase-activating protein (GAP) leads to massive expansion of the lacunar system that contains mislocalized diaphragm components: Sns and Pyd/ZO-1. We find that loss of Snz enhances while its overexpression impairs secretion, which, together with genetic epistasis analyses, suggest that Snz counteracts Rab11 to maintain the diaphragm via setting the proper balance of exocytosis and endocytosis.
Collapse
Affiliation(s)
- Tamás Maruzs
- Institute of Genetics, Biological Research Centre, Eötvös Loránd Research Network, Szeged, H-6726 Hungary
| | - Dalma Feil-Börcsök
- Institute of Genetics, Biological Research Centre, Eötvös Loránd Research Network, Szeged, H-6726 Hungary
- Doctoral School of Biology, University of Szeged, Szeged, H-6726 Hungary
| | - Enikő Lakatos
- Institute of Genetics, Biological Research Centre, Eötvös Loránd Research Network, Szeged, H-6726 Hungary
- Doctoral School of Biology, University of Szeged, Szeged, H-6726 Hungary
| | - Gábor Juhász
- Institute of Genetics, Biological Research Centre, Eötvös Loránd Research Network, Szeged, H-6726 Hungary
| | - András Blastyák
- Institute of Genetics, Biological Research Centre, Eötvös Loránd Research Network, Szeged, H-6726 Hungary
| | - Dávid Hargitai
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, H-1117 Hungary
| | - Steve Jean
- Department of Anatomy and Cell Biology, University of Sherbrooke, Sherbrooke, J1E 4K8 Canada
| | - Péter Lőrincz
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, H-1117 Hungary
| | - Gábor Juhász
- Institute of Genetics, Biological Research Centre, Eötvös Loránd Research Network, Szeged, H-6726 Hungary
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, H-1117 Hungary
| |
Collapse
|
14
|
Chen W, Zhang J, Zhang Y, Zhang J, Li W, Sha L, Xia Y, Chen L. Pharmacological modulation of autophagy for epilepsy therapy: opportunities and obstacles. Drug Discov Today 2023; 28:103600. [PMID: 37119963 DOI: 10.1016/j.drudis.2023.103600] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 04/04/2023] [Accepted: 04/24/2023] [Indexed: 05/01/2023]
Abstract
Epilepsy (EP) is a long-term neurological disorder characterized by neuroinflammatory responses, neuronal apoptosis, imbalance between excitatory and inhibitory neurotransmitters, and oxidative stress in the brain. Autophagy is a process of cellular self-regulation to maintain normal physiological functions. Emerging evidence suggests that dysfunctional autophagy pathways in neurons are a potential mechanism underlying EP pathogenesis. In this review, we discuss current evidence and molecular mechanisms of autophagy dysregulation in EP and the probable function of autophagy in epileptogenesis. Moreover, we review the autophagy modulators reported for the treatment of EP models, and discuss the obstacles to, and opportunities for, the potential therapeutic applications of novel autophagy modulators as EP therapies. Teaser: Defective autophagy affects the onset and progression of epilepsy, and many anti-epileptic drugs have autophagy-modulating effects.
Collapse
Affiliation(s)
- Wenqing Chen
- Department of Neurology, Joint Research Institution of Altitude Health and State Key Laboratory of Biotherapy and Cancer Center and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Jifa Zhang
- Department of Neurology, Joint Research Institution of Altitude Health and State Key Laboratory of Biotherapy and Cancer Center and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Yiwen Zhang
- Department of Neurology, Joint Research Institution of Altitude Health and State Key Laboratory of Biotherapy and Cancer Center and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Jiaxian Zhang
- Department of Neurology, Joint Research Institution of Altitude Health and State Key Laboratory of Biotherapy and Cancer Center and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Wanling Li
- Department of Neurology, Joint Research Institution of Altitude Health and State Key Laboratory of Biotherapy and Cancer Center and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Leihao Sha
- Department of Neurology, Joint Research Institution of Altitude Health and State Key Laboratory of Biotherapy and Cancer Center and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Yilin Xia
- Department of Neurology, Joint Research Institution of Altitude Health and State Key Laboratory of Biotherapy and Cancer Center and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Lei Chen
- Department of Neurology, Joint Research Institution of Altitude Health and State Key Laboratory of Biotherapy and Cancer Center and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China.
| |
Collapse
|
15
|
Guillén-Samander A, De Camilli P. Endoplasmic Reticulum Membrane Contact Sites, Lipid Transport, and Neurodegeneration. Cold Spring Harb Perspect Biol 2023; 15:a041257. [PMID: 36123033 PMCID: PMC10071438 DOI: 10.1101/cshperspect.a041257] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The Endoplasmic Reticulum (ER) is an endomembrane system that plays a multiplicity of roles in cell physiology and populates even the most distal cell compartments, including dendritic tips and axon terminals of neurons. Some of its functions are achieved by a cross talk with other intracellular membranous organelles and with the plasma membrane at membrane contacts sites (MCSs). As the ER synthesizes most membrane lipids, lipid exchanges mediated by lipid transfer proteins at MCSs are a particularly important aspect of this cross talk, which synergizes with the cross talk mediated by vesicular transport. Several mutations of genes that encode proteins localized at ER MCSs result in familial neurodegenerative diseases, emphasizing the importance of the normal lipid traffic within cells for a healthy brain. Here, we provide an overview of such diseases, with a specific focus on proteins that directly or indirectly impact lipid transport.
Collapse
Affiliation(s)
- Andrés Guillén-Samander
- Departments of Neuroscience and of Cell Biology, Howard Hughes Medical Institute, Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, Connecticut 06520, USA
- Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, Maryland 20815, USA
| | - Pietro De Camilli
- Departments of Neuroscience and of Cell Biology, Howard Hughes Medical Institute, Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, Connecticut 06520, USA
- Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, Maryland 20815, USA
| |
Collapse
|
16
|
Zhang Y, Chen R, Dong Y, Zhu J, Su K, Liu J, Xu J. Structural Studies Reveal Unique Non-canonical Regulators of G Protein Signaling Homology (RH) Domains in Sorting Nexins. J Mol Biol 2022; 434:167823. [PMID: 36103920 DOI: 10.1016/j.jmb.2022.167823] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 08/30/2022] [Accepted: 09/06/2022] [Indexed: 11/24/2022]
Abstract
As a subgroup of sorting nexins (SNXs) that contain regulator of G protein signaling homology (RH) domain, SNX-RH proteins, including SNX13, SNX14 and SNX25, were proposed to play bifunctional roles in protein sorting and GPCR signaling regulation. However, mechanistic details of SNX-RH proteins functioning via RH domain remain to be illustrated. Here, we delineate crystal structures of the RH domains of SNX13 and SNX25, revealing a homodimer of SNX13 RH domain mediated by unique extended α4 and α5 helices, and a thiol modulated homodimer of SNX25-RH triggered by a unique cysteine on α6 helix. Further studies showed that RH domains of SNX-RH do not possess binding capacity toward Gα subunits, owing to the lack of critical residues for interaction. Thus, this study identifies a group of novel non-canonical RH domains that can act as a dimerization module in sorting nexins, which provides structural basis for mechanism studies on SNX-RH protein functions.
Collapse
Affiliation(s)
- Yulong Zhang
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China; Graduate University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rui Chen
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China; School of Life Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Yan Dong
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China
| | - Jiabin Zhu
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China
| | - Kai Su
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China
| | - Jinsong Liu
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China; Graduate University of Chinese Academy of Sciences, Beijing 100049, China; Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China.
| | - Jinxin Xu
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China; Graduate University of Chinese Academy of Sciences, Beijing 100049, China; Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China.
| |
Collapse
|
17
|
Li S, Chiang CWK, Myint SS, Arroyo K, Chan TF, Morimoto L, Metayer C, de Smith AJ, Walsh KM, Wiemels JL. Localized variation in ancestral admixture identifies pilocytic astrocytoma risk loci among Latino children. PLoS Genet 2022; 18:e1010388. [PMID: 36070312 PMCID: PMC9484652 DOI: 10.1371/journal.pgen.1010388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 09/19/2022] [Accepted: 08/21/2022] [Indexed: 11/18/2022] Open
Abstract
Background Pilocytic astrocytoma (PA) is the most common pediatric brain tumor. PA has at least a 50% higher incidence in populations of European ancestry compared to other ancestral groups, which may be due in part to genetic differences. Methods We first compared the global proportions of European, African, and Amerindian ancestries in 301 PA cases and 1185 controls of self-identified Latino ethnicity from the California Biobank. We then conducted admixture mapping analysis to assess PA risk with local ancestry. Results We found PA cases had a significantly higher proportion of global European ancestry than controls (case median = 0.55, control median = 0.51, P value = 3.5x10-3). Admixture mapping identified 13 SNPs in the 6q14.3 region (SNX14) contributing to risk, as well as three other peaks approaching significance on chromosomes 7, 10 and 13. Downstream fine mapping in these regions revealed several SNPs potentially contributing to childhood PA risk. Conclusions There is a significant difference in genomic ancestry associated with Latino PA risk and several genomic loci potentially mediating this risk. Childhood brain tumors are among the most prevalent and lethal childhood cancers. Despite this, the epidemiology as well as genetic risks are not well defined. For example, children of European ancestry have a higher risk of contracting pilocytic astrocytoma (PA) compared to other ancestries, but the genetic or environmental basis for this is unknown. Latino children are a mixture of multiple ancestries including European, African, and Native American. Using a group of Californian Latino children, we show that the risk of PA increases when a Latino child has a higher proportion of European ancestry. This global ancestry difference shows that germline genetic risk alleles contribute to a higher PA risk in children of European descendent. Moreover, this ancestral risk is localized to specific regions of the genome, especially in Chromosome 6 near the SNX14 gene, which is associated with cancer-related growth signaling pathway described by MAPK/ERK. This result brings us one step closer to understanding the etiology of this common childhood brain tumor.
Collapse
Affiliation(s)
- Shaobo Li
- Center for Genetic Epidemiology, Department of Population and Public Health Sciences, University of Southern California, Los Angeles, California, United States of America
| | - Charleston W. K. Chiang
- Center for Genetic Epidemiology, Department of Population and Public Health Sciences, University of Southern California, Los Angeles, California, United States of America
- Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, California, United States of America
| | - Swe Swe Myint
- Center for Genetic Epidemiology, Department of Population and Public Health Sciences, University of Southern California, Los Angeles, California, United States of America
| | - Katti Arroyo
- Center for Genetic Epidemiology, Department of Population and Public Health Sciences, University of Southern California, Los Angeles, California, United States of America
| | - Tsz Fung Chan
- Center for Genetic Epidemiology, Department of Population and Public Health Sciences, University of Southern California, Los Angeles, California, United States of America
| | - Libby Morimoto
- School of Public Health, University of California Berkeley, Berkeley, California, United States of America
| | - Catherine Metayer
- School of Public Health, University of California Berkeley, Berkeley, California, United States of America
| | - Adam J. de Smith
- Center for Genetic Epidemiology, Department of Population and Public Health Sciences, University of Southern California, Los Angeles, California, United States of America
| | - Kyle M. Walsh
- Division of Neuro-Epidemiology, Department of Neurosurgery, Duke University, Durham, North Carolina, United States of America
- * E-mail: (KMW); (JLW)
| | - Joseph L. Wiemels
- Center for Genetic Epidemiology, Department of Population and Public Health Sciences, University of Southern California, Los Angeles, California, United States of America
- * E-mail: (KMW); (JLW)
| |
Collapse
|
18
|
Chen X, Yao T, Cai J, Zhang Q, Li S, Li H, Fu X, Wu J. A novel genetic variant potentially altering the expression of MANBA in the cerebellum associated with attention deficit hyperactivity disorder in Han Chinese children. World J Biol Psychiatry 2022; 23:548-559. [PMID: 34870556 DOI: 10.1080/15622975.2021.2014248] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVES To obtain additional insight into the genetic factors of attention deficit hyperactivity disorder (ADHD). METHODS First, we performed a transcriptome-wide association study (TWAS) integrating human cerebellum-specific variant-expression/splicing correlations to identify ADHD susceptibility genes. Then, the associations between expression/splicing quantitative trait loci (eQTLs/sQTLs) of the transcriptome-wide significant genes and ADHD were observed in a case-control study of Han Chinese children. Furthermore, dual luciferase reporter gene assays were performed to validate the regulatory function of ADHD risk variants. Additionally, the transcription level of target genes in blood was detected by real-time quantitative polymerase chain reaction (RT-qPCR) assay. RESULTS TWAS identified that the genetically regulated expression of MANBA in the cerebellum was significantly associated with ADHD risk. Furthermore, we observed a higher risk of ADHD and more severe clinical symptoms in subjects harbouring heterozygous (TC) or mutant homozygous (TT) genotypes of MANBA rs1054037 than CC carriers. The dual luciferase reporter gene assay revealed that the mutation of rs1054037(C > T) potentially upregulated MANBA expression by eliminating the binding site for hsa-miR-5591-3P. Finally, RT-qPCR showed that MANBA expression in blood samples of patients was significantly higher than that of controls. CONCLUSIONS Taken together, these results suggest a role of MANBA in the development of ADHD.
Collapse
Affiliation(s)
- Xinzhen Chen
- Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ting Yao
- Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jinliang Cai
- Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Qi Zhang
- Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Shanyawen Li
- Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Huiru Li
- Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xihang Fu
- Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jing Wu
- Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| |
Collapse
|
19
|
Molecular Mechanism and Regulation of Autophagy and Its Potential Role in Epilepsy. Cells 2022; 11:cells11172621. [PMID: 36078029 PMCID: PMC9455075 DOI: 10.3390/cells11172621] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 08/14/2022] [Accepted: 08/22/2022] [Indexed: 01/18/2023] Open
Abstract
Autophagy is an evolutionally conserved degradation mechanism for maintaining cell homeostasis whereby cytoplasmic components are wrapped in autophagosomes and subsequently delivered to lysosomes for degradation. This process requires the concerted actions of multiple autophagy-related proteins and accessory regulators. In neurons, autophagy is dynamically regulated in different compartments including soma, axons, and dendrites. It determines the turnover of selected materials in a spatiotemporal control manner, which facilitates the formation of specialized neuronal functions. It is not surprising, therefore, that dysfunctional autophagy occurs in epilepsy, mainly caused by an imbalance between excitation and inhibition in the brain. In recent years, much attention has been focused on how autophagy may cause the development of epilepsy. In this article, we overview the historical landmarks and distinct types of autophagy, recent progress in the core machinery and regulation of autophagy, and biological roles of autophagy in homeostatic maintenance of neuronal structures and functions, with a particular focus on synaptic plasticity. We also discuss the relevance of autophagy mechanisms to the pathophysiology of epileptogenesis.
Collapse
|
20
|
Kim S, Coukos R, Gao F, Krainc D. Dysregulation of organelle membrane contact sites in neurological diseases. Neuron 2022; 110:2386-2408. [PMID: 35561676 PMCID: PMC9357093 DOI: 10.1016/j.neuron.2022.04.020] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/21/2022] [Accepted: 04/18/2022] [Indexed: 10/18/2022]
Abstract
The defining evolutionary feature of eukaryotic cells is the emergence of membrane-bound organelles. Compartmentalization allows each organelle to maintain a spatially, physically, and chemically distinct environment, which greatly bolsters individual organelle function. However, the activities of each organelle must be balanced and are interdependent for cellular homeostasis. Therefore, properly regulated interactions between organelles, either physically or functionally, remain critical for overall cellular health and behavior. In particular, neuronal homeostasis depends heavily on the proper regulation of organelle function and cross talk, and deficits in these functions are frequently associated with diseases. In this review, we examine the emerging role of organelle contacts in neurological diseases and discuss how the disruption of contacts contributes to disease pathogenesis. Understanding the molecular mechanisms underlying the formation and regulation of organelle contacts will broaden our knowledge of their role in health and disease, laying the groundwork for the development of new therapies targeting interorganelle cross talk and function.
Collapse
Affiliation(s)
- Soojin Kim
- Department of Neurology, Northwestern University Feinberg School of Medicine, 303 E Chicago Avenue, Chicago, IL, 60611, USA
| | - Robert Coukos
- Department of Neurology, Northwestern University Feinberg School of Medicine, 303 E Chicago Avenue, Chicago, IL, 60611, USA
| | - Fanding Gao
- Department of Neurology, Northwestern University Feinberg School of Medicine, 303 E Chicago Avenue, Chicago, IL, 60611, USA
| | - Dimitri Krainc
- Department of Neurology, Northwestern University Feinberg School of Medicine, 303 E Chicago Avenue, Chicago, IL 60611, USA.
| |
Collapse
|
21
|
Abstract
Macroautophagy is an evolutionarily conserved process that delivers diverse cellular contents to lysosomes for degradation. As our understanding of this pathway grows, so does our appreciation for its importance in disorders of the CNS. Once implicated primarily in neurodegenerative events owing to acute injury and ageing, macroautophagy is now also linked to disorders of neurodevelopment, indicating that it is essential for both the formation and maintenance of a healthy CNS. In parallel to understanding the significance of macroautophagy across contexts, we have gained a greater mechanistic insight into its physiological regulation and the breadth of cargoes it can degrade. Macroautophagy is a broadly used homeostatic process, giving rise to questions surrounding how defects in this single pathway could cause diseases with distinct clinical and pathological signatures. To address this complexity, we herein review macroautophagy in the mammalian CNS by examining three key features of the process and its relationship to disease: how it functions at a basal level in the discrete cell types of the brain and spinal cord; which cargoes are being degraded in physiological and pathological settings; and how the different stages of the macroautophagy pathway intersect with diseases of neurodevelopment and adult-onset neurodegeneration.
Collapse
Affiliation(s)
- Christopher J Griffey
- Doctoral Program in Neurobiology and Behaviour, Medical Scientist Training Program, Columbia University, New York, NY, USA
| | - Ai Yamamoto
- Departments of Neurology, and Pathology and Cell Biology, Columbia University, New York, NY, USA.
| |
Collapse
|
22
|
Zhao J, Zhang H, Fan X, Yu X, Huai J. Lipid Dyshomeostasis and Inherited Cerebellar Ataxia. Mol Neurobiol 2022; 59:3800-3828. [PMID: 35420383 PMCID: PMC9148275 DOI: 10.1007/s12035-022-02826-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 04/01/2022] [Indexed: 12/04/2022]
Abstract
Cerebellar ataxia is a form of ataxia that originates from dysfunction of the cerebellum, but may involve additional neurological tissues. Its clinical symptoms are mainly characterized by the absence of voluntary muscle coordination and loss of control of movement with varying manifestations due to differences in severity, in the site of cerebellar damage and in the involvement of extracerebellar tissues. Cerebellar ataxia may be sporadic, acquired, and hereditary. Hereditary ataxia accounts for the majority of cases. Hereditary ataxia has been tentatively divided into several subtypes by scientists in the field, and nearly all of them remain incurable. This is mainly because the detailed mechanisms of these cerebellar disorders are incompletely understood. To precisely diagnose and treat these diseases, studies on their molecular mechanisms have been conducted extensively in the past. Accumulating evidence has demonstrated that some common pathogenic mechanisms exist within each subtype of inherited ataxia. However, no reports have indicated whether there is a common mechanism among the different subtypes of inherited cerebellar ataxia. In this review, we summarize the available references and databases on neurological disorders characterized by cerebellar ataxia and show that a subset of genes involved in lipid homeostasis form a new group that may cause ataxic disorders through a common mechanism. This common signaling pathway can provide a valuable reference for future diagnosis and treatment of ataxic disorders.
Collapse
Affiliation(s)
- Jin Zhao
- The Second Affiliated Hospital of Xinxiang Medical University (Henan Mental Hospital), Xinxiang, 453000, China
- Institute of Psychiatry and Neuroscience, Xinxiang Medical University, Xinxiang, 453003, China
| | - Huan Zhang
- The Second Affiliated Hospital of Xinxiang Medical University (Henan Mental Hospital), Xinxiang, 453000, China
- Institute of Psychiatry and Neuroscience, Xinxiang Medical University, Xinxiang, 453003, China
| | - Xueyu Fan
- The Second Affiliated Hospital of Xinxiang Medical University (Henan Mental Hospital), Xinxiang, 453000, China
- Institute of Psychiatry and Neuroscience, Xinxiang Medical University, Xinxiang, 453003, China
| | - Xue Yu
- The Second Affiliated Hospital of Xinxiang Medical University (Henan Mental Hospital), Xinxiang, 453000, China
- Institute of Psychiatry and Neuroscience, Xinxiang Medical University, Xinxiang, 453003, China
| | - Jisen Huai
- The Second Affiliated Hospital of Xinxiang Medical University (Henan Mental Hospital), Xinxiang, 453000, China.
- Institute of Psychiatry and Neuroscience, Xinxiang Medical University, Xinxiang, 453003, China.
| |
Collapse
|
23
|
Abstract
SNX-RGS proteins are molecular tethers localized to multiple interorganelle contact sites that exhibit roles in cellular metabolism. Here, we highlight recent findings on these proteins and discuss their emerging roles in metabolism, human disease, and lipid trafficking.
Collapse
Affiliation(s)
- Hanaa Hariri
- Department of Biological Sciences, Wayne State University, Detroit, MI
| | - W. Mike Henne
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX
| |
Collapse
|
24
|
Laurent A, Madigou T, Bizot M, Turpin M, Palierne G, Mahé E, Guimard S, Métivier R, Avner S, Le Péron C, Salbert G. TET2-mediated epigenetic reprogramming of breast cancer cells impairs lysosome biogenesis. Life Sci Alliance 2022; 5:5/7/e202101283. [PMID: 35351824 PMCID: PMC8963717 DOI: 10.26508/lsa.202101283] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 03/11/2022] [Accepted: 03/14/2022] [Indexed: 11/24/2022] Open
Abstract
TET2-mediated oxidation of 5-methylcytosine establishes an antiviral state and contributes to MYC-dependent down-regulation of genes involved in lysosome biogenesis and function in breast cancer cells. Methylation and demethylation of cytosines in DNA are believed to act as keystones of cell-specific gene expression by controlling the chromatin structure and accessibility to transcription factors. Cancer cells have their own transcriptional programs, and we sought to alter such a cancer-specific program by enforcing expression of the catalytic domain (CD) of the methylcytosine dioxygenase TET2 in breast cancer cells. The TET2 CD decreased the tumorigenic potential of cancer cells through both activation and repression of a repertoire of genes that, interestingly, differed in part from the one observed upon treatment with the hypomethylating agent decitabine. In addition to promoting the establishment of an antiviral state, TET2 activated 5mC turnover at thousands of MYC-binding motifs and down-regulated a panel of known MYC-repressed genes involved in lysosome biogenesis and function. Thus, an extensive cross-talk between TET2 and the oncogenic transcription factor MYC establishes a lysosomal storage disease–like state that contributes to an exacerbated sensitivity to autophagy inducers.
Collapse
Affiliation(s)
- Audrey Laurent
- Université Rennes 1, CNRS UMR6290, Institut de Génétique et Développement de Rennes, Campus de Beaulieu, Rennes, France
| | - Thierry Madigou
- Université Rennes 1, CNRS UMR6290, Institut de Génétique et Développement de Rennes, Campus de Beaulieu, Rennes, France
| | - Maud Bizot
- Université Rennes 1, CNRS UMR6290, Institut de Génétique et Développement de Rennes, Campus de Beaulieu, Rennes, France
| | - Marion Turpin
- Université Rennes 1, CNRS UMR6290, Institut de Génétique et Développement de Rennes, Campus de Beaulieu, Rennes, France
| | - Gaëlle Palierne
- Université Rennes 1, CNRS UMR6290, Institut de Génétique et Développement de Rennes, Campus de Beaulieu, Rennes, France
| | - Elise Mahé
- Université Rennes 1, CNRS UMR6290, Institut de Génétique et Développement de Rennes, Campus de Beaulieu, Rennes, France
| | - Sarah Guimard
- Université Rennes 1, CNRS UMR6290, Institut de Génétique et Développement de Rennes, Campus de Beaulieu, Rennes, France
| | - Raphaël Métivier
- Université Rennes 1, CNRS UMR6290, Institut de Génétique et Développement de Rennes, Campus de Beaulieu, Rennes, France
| | - Stéphane Avner
- Université Rennes 1, CNRS UMR6290, Institut de Génétique et Développement de Rennes, Campus de Beaulieu, Rennes, France
| | - Christine Le Péron
- Université Rennes 1, CNRS UMR6290, Institut de Génétique et Développement de Rennes, Campus de Beaulieu, Rennes, France
| | - Gilles Salbert
- Université Rennes 1, CNRS UMR6290, Institut de Génétique et Développement de Rennes, Campus de Beaulieu, Rennes, France
| |
Collapse
|
25
|
Fleming A, Bourdenx M, Fujimaki M, Karabiyik C, Krause GJ, Lopez A, Martín-Segura A, Puri C, Scrivo A, Skidmore J, Son SM, Stamatakou E, Wrobel L, Zhu Y, Cuervo AM, Rubinsztein DC. The different autophagy degradation pathways and neurodegeneration. Neuron 2022; 110:935-966. [PMID: 35134347 PMCID: PMC8930707 DOI: 10.1016/j.neuron.2022.01.017] [Citation(s) in RCA: 250] [Impact Index Per Article: 83.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 12/31/2021] [Accepted: 01/11/2022] [Indexed: 12/11/2022]
Abstract
The term autophagy encompasses different pathways that route cytoplasmic material to lysosomes for degradation and includes macroautophagy, chaperone-mediated autophagy, and microautophagy. Since these pathways are crucial for degradation of aggregate-prone proteins and dysfunctional organelles such as mitochondria, they help to maintain cellular homeostasis. As post-mitotic neurons cannot dilute unwanted protein and organelle accumulation by cell division, the nervous system is particularly dependent on autophagic pathways. This dependence may be a vulnerability as people age and these processes become less effective in the brain. Here, we will review how the different autophagic pathways may protect against neurodegeneration, giving examples of both polygenic and monogenic diseases. We have considered how autophagy may have roles in normal CNS functions and the relationships between these degradative pathways and different types of programmed cell death. Finally, we will provide an overview of recently described strategies for upregulating autophagic pathways for therapeutic purposes.
Collapse
Affiliation(s)
- Angeleen Fleming
- Department of Medical Genetics, University of Cambridge, Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK; UK Dementia Research Institute, University of Cambridge, Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK; Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Mathieu Bourdenx
- Université de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France; CNRS, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France
| | - Motoki Fujimaki
- Department of Medical Genetics, University of Cambridge, Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK; UK Dementia Research Institute, University of Cambridge, Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Cansu Karabiyik
- Department of Medical Genetics, University of Cambridge, Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK; UK Dementia Research Institute, University of Cambridge, Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Gregory J Krause
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY, USA; Institute for Aging Studies, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Ana Lopez
- Department of Medical Genetics, University of Cambridge, Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK; UK Dementia Research Institute, University of Cambridge, Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK; Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Adrián Martín-Segura
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY, USA; Institute for Aging Studies, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Claudia Puri
- Department of Medical Genetics, University of Cambridge, Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK; UK Dementia Research Institute, University of Cambridge, Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Aurora Scrivo
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY, USA; Institute for Aging Studies, Albert Einstein College of Medicine, Bronx, NY, USA
| | - John Skidmore
- The ALBORADA Drug Discovery Institute, University of Cambridge, Island Research Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0AH, UK
| | - Sung Min Son
- Department of Medical Genetics, University of Cambridge, Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK; UK Dementia Research Institute, University of Cambridge, Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Eleanna Stamatakou
- Department of Medical Genetics, University of Cambridge, Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK; UK Dementia Research Institute, University of Cambridge, Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Lidia Wrobel
- Department of Medical Genetics, University of Cambridge, Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK; UK Dementia Research Institute, University of Cambridge, Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Ye Zhu
- Department of Medical Genetics, University of Cambridge, Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK; UK Dementia Research Institute, University of Cambridge, Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Ana Maria Cuervo
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY, USA; Institute for Aging Studies, Albert Einstein College of Medicine, Bronx, NY, USA.
| | - David C Rubinsztein
- Department of Medical Genetics, University of Cambridge, Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK; UK Dementia Research Institute, University of Cambridge, Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK.
| |
Collapse
|
26
|
Deneubourg C, Ramm M, Smith LJ, Baron O, Singh K, Byrne SC, Duchen MR, Gautel M, Eskelinen EL, Fanto M, Jungbluth H. The spectrum of neurodevelopmental, neuromuscular and neurodegenerative disorders due to defective autophagy. Autophagy 2022; 18:496-517. [PMID: 34130600 PMCID: PMC9037555 DOI: 10.1080/15548627.2021.1943177] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 06/10/2021] [Indexed: 12/15/2022] Open
Abstract
Primary dysfunction of autophagy due to Mendelian defects affecting core components of the autophagy machinery or closely related proteins have recently emerged as an important cause of genetic disease. This novel group of human disorders may present throughout life and comprises severe early-onset neurodevelopmental and more common adult-onset neurodegenerative disorders. Early-onset (or congenital) disorders of autophagy often share a recognizable "clinical signature," including variable combinations of neurological, neuromuscular and multisystem manifestations. Structural CNS abnormalities, cerebellar involvement, spasticity and peripheral nerve pathology are prominent neurological features, indicating a specific vulnerability of certain neuronal populations to autophagic disturbance. A typically biphasic disease course of late-onset neurodegeneration occurring on the background of a neurodevelopmental disorder further supports a role of autophagy in both neuronal development and maintenance. Additionally, an associated myopathy has been characterized in several conditions. The differential diagnosis comprises a wide range of other multisystem disorders, including mitochondrial, glycogen and lysosomal storage disorders, as well as ciliopathies, glycosylation and vesicular trafficking defects. The clinical overlap between the congenital disorders of autophagy and these conditions reflects the multiple roles of the proteins and/or emerging molecular connections between the pathways implicated and suggests an exciting area for future research. Therapy development for congenital disorders of autophagy is still in its infancy but may result in the identification of molecules that target autophagy more specifically than currently available compounds. The close connection with adult-onset neurodegenerative disorders highlights the relevance of research into rare early-onset neurodevelopmental conditions for much more common, age-related human diseases.Abbreviations: AC: anterior commissure; AD: Alzheimer disease; ALR: autophagic lysosomal reformation; ALS: amyotrophic lateral sclerosis; AMBRA1: autophagy and beclin 1 regulator 1; AMPK: AMP-activated protein kinase; ASD: autism spectrum disorder; ATG: autophagy related; BIN1: bridging integrator 1; BPAN: beta-propeller protein associated neurodegeneration; CC: corpus callosum; CHMP2B: charged multivesicular body protein 2B; CHS: Chediak-Higashi syndrome; CMA: chaperone-mediated autophagy; CMT: Charcot-Marie-Tooth disease; CNM: centronuclear myopathy; CNS: central nervous system; DNM2: dynamin 2; DPR: dipeptide repeat protein; DVL3: disheveled segment polarity protein 3; EPG5: ectopic P-granules autophagy protein 5 homolog; ER: endoplasmic reticulum; ESCRT: homotypic fusion and protein sorting complex; FIG4: FIG4 phosphoinositide 5-phosphatase; FTD: frontotemporal dementia; GBA: glucocerebrosidase; GD: Gaucher disease; GRN: progranulin; GSD: glycogen storage disorder; HC: hippocampal commissure; HD: Huntington disease; HOPS: homotypic fusion and protein sorting complex; HSPP: hereditary spastic paraparesis; LAMP2A: lysosomal associated membrane protein 2A; MEAX: X-linked myopathy with excessive autophagy; mHTT: mutant huntingtin; MSS: Marinesco-Sjoegren syndrome; MTM1: myotubularin 1; MTOR: mechanistic target of rapamycin kinase; NBIA: neurodegeneration with brain iron accumulation; NCL: neuronal ceroid lipofuscinosis; NPC1: Niemann-Pick disease type 1; PD: Parkinson disease; PtdIns3P: phosphatidylinositol-3-phosphate; RAB3GAP1: RAB3 GTPase activating protein catalytic subunit 1; RAB3GAP2: RAB3 GTPase activating non-catalytic protein subunit 2; RB1: RB1-inducible coiled-coil protein 1; RHEB: ras homolog, mTORC1 binding; SCAR20: SNX14-related ataxia; SENDA: static encephalopathy of childhood with neurodegeneration in adulthood; SNX14: sorting nexin 14; SPG11: SPG11 vesicle trafficking associated, spatacsin; SQSTM1: sequestosome 1; TBC1D20: TBC1 domain family member 20; TECPR2: tectonin beta-propeller repeat containing 2; TSC1: TSC complex subunit 1; TSC2: TSC complex subunit 2; UBQLN2: ubiquilin 2; VCP: valosin-containing protein; VMA21: vacuolar ATPase assembly factor VMA21; WDFY3/ALFY: WD repeat and FYVE domain containing protein 3; WDR45: WD repeat domain 45; WDR47: WD repeat domain 47; WMS: Warburg Micro syndrome; XLMTM: X-linked myotubular myopathy; ZFYVE26: zinc finger FYVE-type containing 26.
Collapse
Affiliation(s)
- Celine Deneubourg
- Department of Basic and Clinical Neuroscience, IoPPN, King’s College London, London, UK
| | - Mauricio Ramm
- Institute of Biomedicine, University of Turku, Turku, Finland
| | - Luke J. Smith
- Randall Division of Cell and Molecular Biophysics, Muscle Signalling Section, King’s College London, London, UK
| | - Olga Baron
- Wolfson Centre for Age-Related Diseases, King’s College London, London, UK
| | - Kritarth Singh
- Department of Cell and Developmental Biology, University College London, London, UK
| | - Susan C. Byrne
- Department of Paediatric Neurology, Neuromuscular Service, Evelina’s Children Hospital, Guy’s & St. Thomas’ Hospital NHS Foundation Trust, London, UK
| | - Michael R. Duchen
- Department of Cell and Developmental Biology, University College London, London, UK
| | - Mathias Gautel
- Randall Division of Cell and Molecular Biophysics, Muscle Signalling Section, King’s College London, London, UK
| | - Eeva-Liisa Eskelinen
- Institute of Biomedicine, University of Turku, Turku, Finland
- Molecular and Integrative Biosciences Research Programme, University of Helsinki, Helsinki, Finland
| | - Manolis Fanto
- Department of Basic and Clinical Neuroscience, IoPPN, King’s College London, London, UK
| | - Heinz Jungbluth
- Department of Basic and Clinical Neuroscience, IoPPN, King’s College London, London, UK
- Randall Division of Cell and Molecular Biophysics, Muscle Signalling Section, King’s College London, London, UK
- Department of Paediatric Neurology, Neuromuscular Service, Evelina’s Children Hospital, Guy’s & St. Thomas’ Hospital NHS Foundation Trust, London, UK
| |
Collapse
|
27
|
Lauzier A, Bossanyi MF, Larcher R, Nassari S, Ugrankar R, Henne WM, Jean S. Snazarus and its human ortholog SNX25 modulate autophagic flux. J Cell Sci 2022; 135:273525. [PMID: 34821359 DOI: 10.1242/jcs.258733] [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: 04/08/2021] [Accepted: 11/12/2021] [Indexed: 12/26/2022] Open
Abstract
Macroautophagy, the degradation and recycling of cytosolic components in the lysosome, is an important cellular mechanism. It is a membrane-mediated process that is linked to vesicular trafficking events. The sorting nexin (SNX) protein family controls the sorting of a large array of cargoes, and various SNXs impact autophagy. To improve our understanding of their functions in vivo, we screened all Drosophila SNXs using inducible RNA interference in the fat body. Significantly, depletion of Snazarus (Snz) led to decreased autophagic flux. Interestingly, we observed altered distribution of Vamp7-positive vesicles with Snz depletion, and the roles of Snz were conserved in human cells. SNX25, the closest human ortholog to Snz, regulates both VAMP8 endocytosis and lipid metabolism. Through knockout-rescue experiments, we demonstrate that these activities are dependent on specific SNX25 domains and that the autophagic defects seen upon SNX25 loss can be rescued by ethanolamine addition. We also demonstrate the presence of differentially spliced forms of SNX14 and SNX25 in cancer cells. This work identifies a conserved role for Snz/SNX25 as a regulator of autophagic flux and reveals differential isoform expression between paralogs.
Collapse
Affiliation(s)
- Annie Lauzier
- Faculté de Médecine et des Sciences de la Santé, Département d'immunologie et de biologie cellulaire, Université de Sherbrooke, 3201, Rue Jean Mignault, Sherbrooke, Québec, CanadaJ1E 4K8
| | - Marie-France Bossanyi
- Faculté de Médecine et des Sciences de la Santé, Département d'immunologie et de biologie cellulaire, Université de Sherbrooke, 3201, Rue Jean Mignault, Sherbrooke, Québec, CanadaJ1E 4K8
| | - Raphaëlle Larcher
- Faculté de Médecine et des Sciences de la Santé, Département d'immunologie et de biologie cellulaire, Université de Sherbrooke, 3201, Rue Jean Mignault, Sherbrooke, Québec, CanadaJ1E 4K8
| | - Sonya Nassari
- Faculté de Médecine et des Sciences de la Santé, Département d'immunologie et de biologie cellulaire, Université de Sherbrooke, 3201, Rue Jean Mignault, Sherbrooke, Québec, CanadaJ1E 4K8
| | - Rupali Ugrankar
- Department of Cell Biology, UT Southwestern Medical Center, 6000 Hary Lines Boulevard, Dallas, TX 75390, USA
| | - W Mike Henne
- Department of Cell Biology, UT Southwestern Medical Center, 6000 Hary Lines Boulevard, Dallas, TX 75390, USA
| | - Steve Jean
- Faculté de Médecine et des Sciences de la Santé, Département d'immunologie et de biologie cellulaire, Université de Sherbrooke, 3201, Rue Jean Mignault, Sherbrooke, Québec, CanadaJ1E 4K8
| |
Collapse
|
28
|
Sait H, Moirangthem A, Agrawal V, Phadke SR. Autosomal recessive spinocerebellar ataxia-20 due to a novel SNX14 variant in an Indian girl. Am J Med Genet A 2022; 188:1909-1914. [PMID: 35195341 DOI: 10.1002/ajmg.a.62701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 01/21/2022] [Accepted: 02/05/2022] [Indexed: 11/11/2022]
Abstract
Autosomal recessive spinocerebellar ataxia-20 is a rare disorder having distinctive coarse facies in addition to intellectual disability and cerebellar ataxia, with less than 35 cases reported worldwide. It is caused by biallelic variants in the SNX14 gene and is classified under the group of autophagy disorders. We report a 9-year-old girl who presented with classic clinical features of autosomal recessive spinocerebellar ataxia-20 and cerebellar atrophy on magnetic resonance imaging of brain. Trio exome sequencing with Sanger confirmation revealed a novel splice site variant, c.140 + 3A > T in the SNX14 gene. The variant pathogenicity established by mRNA expression study showed a significant reduction in the expression levels of SNX14 gene in proband and her parents on comparison to the control. The electron microscopy of the skin fibroblasts of proband depicted numerous cytoplasmic vacuoles with variable degrees of dense staining material. In addition, we have briefly reviewed and compared the phenotypic features of published cases of autosomal recessive spinocerebellar ataxia-20 in the literature. Coarse facies, intellectual disability with severe speech delay, hypotonia, and cerebellar atrophy were universal findings in the published cases. This is the second reported case from the Indian subcontinent.
Collapse
Affiliation(s)
- Haseena Sait
- Department of Medical Genetics, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India
| | - Amita Moirangthem
- Department of Medical Genetics, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India
| | - Vinita Agrawal
- Department of Pathology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India
| | - Shubha R Phadke
- Department of Medical Genetics, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India
| |
Collapse
|
29
|
Paul B, Weeratunga S, Tillu VA, Hariri H, Henne WM, Collins BM. Structural Predictions of the SNX-RGS Proteins Suggest They Belong to a New Class of Lipid Transfer Proteins. Front Cell Dev Biol 2022; 10:826688. [PMID: 35223850 PMCID: PMC8864675 DOI: 10.3389/fcell.2022.826688] [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: 12/01/2021] [Accepted: 01/13/2022] [Indexed: 12/12/2022] Open
Abstract
Recent advances in protein structure prediction using machine learning such as AlphaFold2 and RosettaFold presage a revolution in structural biology. Genome-wide predictions of protein structures are providing unprecedented insights into their architecture and intradomain interactions, and applications have already progressed towards assessing protein complex formation. Here we present detailed analyses of the sorting nexin proteins that contain regulator of G-protein signalling domains (SNX-RGS proteins), providing a key example of the ability of AlphaFold2 to reveal novel structures with previously unsuspected biological functions. These large proteins are conserved in most eukaryotes and are known to associate with lipid droplets (LDs) and sites of LD-membrane contacts, with key roles in regulating lipid metabolism. They possess five domains, including an N-terminal transmembrane domain that anchors them to the endoplasmic reticulum, an RGS domain, a lipid interacting phox homology (PX) domain and two additional domains named the PXA and PXC domains of unknown structure and function. Here we report the crystal structure of the RGS domain of sorting nexin 25 (SNX25) and show that the AlphaFold2 prediction closely matches the experimental structure. Analysing the full-length SNX-RGS proteins across multiple homologues and species we find that the distant PXA and PXC domains in fact fold into a single unique structure that notably features a large and conserved hydrophobic pocket. The nature of this pocket strongly suggests a role in lipid or fatty acid binding, and we propose that these molecules represent a new class of conserved lipid transfer proteins.
Collapse
Affiliation(s)
- Blessy Paul
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, Australia
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Saroja Weeratunga
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, Australia
| | - Vikas A. Tillu
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, Australia
| | - Hanaa Hariri
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - W. Mike Henne
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Brett M. Collins
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, Australia
| |
Collapse
|
30
|
Abstract
Phosphoinositides are signalling lipids derived from phosphatidylinositol, a ubiquitous phospholipid in the cytoplasmic leaflet of eukaryotic membranes. Initially discovered for their roles in cell signalling, phosphoinositides are now widely recognized as key integrators of membrane dynamics that broadly impact on all aspects of cell physiology and on disease. The past decade has witnessed a vast expansion of our knowledge of phosphoinositide biology. On the endocytic and exocytic routes, phosphoinositides direct the inward and outward flow of membrane as vesicular traffic is coupled to the conversion of phosphoinositides. Moreover, recent findings on the roles of phosphoinositides in autophagy and the endolysosomal system challenge our view of lysosome biology. The non-vesicular exchange of lipids, ions and metabolites at membrane contact sites in between organelles has also been found to depend on phosphoinositides. Here we review our current understanding of how phosphoinositides shape and direct membrane dynamics to impact on cell physiology, and provide an overview of emerging concepts in phosphoinositide regulation.
Collapse
|
31
|
Wen X, Yang Y, Klionsky DJ. Moments in autophagy and disease: Past and present. Mol Aspects Med 2021; 82:100966. [PMID: 33931245 PMCID: PMC8548407 DOI: 10.1016/j.mam.2021.100966] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 04/13/2021] [Accepted: 04/19/2021] [Indexed: 01/18/2023]
Abstract
Over the past several decades, research on autophagy, a highly conserved lysosomal degradation pathway, has been advanced by studies in different model organisms, especially in the field of its molecular mechanism and regulation. The malfunction of autophagy is linked to various diseases, among which cancer and neurodegenerative diseases are the major focus. In this review, we cover some other important diseases, including cardiovascular diseases, infectious and inflammatory diseases, and metabolic disorders, as well as rare diseases, with a hope of providing a more complete understanding of the spectrum of autophagy's role in human health.
Collapse
Affiliation(s)
- Xin Wen
- Life Sciences Institute, Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Ying Yang
- Life Sciences Institute, Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Daniel J Klionsky
- Life Sciences Institute, Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, USA.
| |
Collapse
|
32
|
Zhang H, Hong Y, Yang W, Wang R, Yao T, Wang J, Liu K, Yuan H, Xu C, Zhou Y, Li G, Zhang L, Luo H, Zhang X, Du D, Sun H, Zheng Q, Zhang YW, Zhao Y, Zhou Y, Xu H, Wang X. SNX14 deficiency-induced defective axonal mitochondrial transport in Purkinje cells underlies cerebellar ataxia and can be reversed by valproate. Natl Sci Rev 2021; 8:nwab024. [PMID: 34691693 PMCID: PMC8310771 DOI: 10.1093/nsr/nwab024] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Revised: 01/18/2021] [Accepted: 02/05/2021] [Indexed: 12/11/2022] Open
Abstract
Loss-of-function mutations in sorting nexin 14 (SNX14) cause autosomal recessive spinocerebellar ataxia 20, which is a form of early-onset cerebellar ataxia that lacks molecular mechanisms and mouse models. We generated Snx14-deficient mouse models and observed severe motor deficits and cell-autonomous Purkinje cell degeneration. SNX14 deficiency disrupted microtubule organization and mitochondrial transport in axons by destabilizing the microtubule-severing enzyme spastin, which is implicated in dominant hereditary spastic paraplegia with cerebellar ataxia, and compromised axonal integrity and mitochondrial function. Axonal transport disruption and mitochondrial dysfunction further led to degeneration of high-energy-demanding Purkinje cells, which resulted in the pathogenesis of cerebellar ataxia. The antiepileptic drug valproate ameliorated motor deficits and cerebellar degeneration in Snx14-deficient mice via the restoration of mitochondrial transport and function in Purkinje cells. Our study revealed an unprecedented role for SNX14-dependent axonal transport in cerebellar ataxia, demonstrated the convergence of SNX14 and spastin in mitochondrial dysfunction, and suggested valproate as a potential therapeutic agent.
Collapse
Affiliation(s)
- Hongfeng Zhang
- State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Yujuan Hong
- State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Weijie Yang
- State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Ruimin Wang
- State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Ting Yao
- State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Jian Wang
- State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Ke Liu
- National Institute for Data Science in Health and Medicine, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Huilong Yuan
- State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Chaoqun Xu
- National Institute for Data Science in Health and Medicine, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Yuanyuan Zhou
- State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Guanxian Li
- State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Lishan Zhang
- State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Hong Luo
- State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Xian Zhang
- State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Dan Du
- Cancer Research Center, Department of Stomatology, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Hao Sun
- State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Qiuyang Zheng
- State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Yun-Wu Zhang
- State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Yingjun Zhao
- State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Ying Zhou
- National Institute for Data Science in Health and Medicine, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Huaxi Xu
- State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen 361102, China
| | - Xin Wang
- State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen 361102, China
| |
Collapse
|
33
|
Walkley SU. Rethinking lysosomes and lysosomal disease. Neurosci Lett 2021; 762:136155. [PMID: 34358625 DOI: 10.1016/j.neulet.2021.136155] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 07/14/2021] [Accepted: 07/27/2021] [Indexed: 12/15/2022]
Abstract
Lysosomal storage diseases were recognized and defined over a century ago as a class of disorders affecting mostly children and causing systemic disease often accompanied by major neurological consequences. Since their discovery, research focused on understanding their causes has been an important driver of our ever-expanding knowledge of cell biology and the central role that lysosomes play in cell function. Today we recognize over 50 so-called storage diseases, with most understood at the level of gene, protein and pathway involvement, but few fully clarified in terms of how the defective lysosomal function causes brain disease; even fewer have therapies that can effectively rescue brain function. Importantly, we also recognize that storage diseases are not simply a class of lysosomal disorders all by themselves, as increasingly a critical role for the greater lysosomal system with its endosomal, autophagosomal and salvage streams has also emerged in a host of neurodevelopmental and neurodegenerative diseases. Despite persistent challenges across all aspects of these complex disorders, and as reflected in this and other articles focused on lysosomal storage diseases in this special issue of Neuroscience Letters, the progress and promise to both understand and effectively treat these conditions has never been greater.
Collapse
Affiliation(s)
- Steven U Walkley
- Department of Neuroscience, Rose F. Kennedy Intellectual and Developmental Disabilities Research Center, Albert Einstein College of Medicine, Bronx, NY, USA.
| |
Collapse
|
34
|
Saric A, Freeman SA, Williamson CD, Jarnik M, Guardia CM, Fernandopulle MS, Gershlick DC, Bonifacino JS. SNX19 restricts endolysosome motility through contacts with the endoplasmic reticulum. Nat Commun 2021; 12:4552. [PMID: 34315878 PMCID: PMC8316374 DOI: 10.1038/s41467-021-24709-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 06/24/2021] [Indexed: 12/12/2022] Open
Abstract
The ability of endolysosomal organelles to move within the cytoplasm is essential for the performance of their functions. Long-range movement involves coupling of the endolysosomes to motor proteins that carry them along microtubule tracks. This movement is influenced by interactions with other organelles, but the mechanisms involved are incompletely understood. Herein we show that the sorting nexin SNX19 tethers endolysosomes to the endoplasmic reticulum (ER), decreasing their motility and contributing to their concentration in the perinuclear area of the cell. Tethering depends on two N-terminal transmembrane domains that anchor SNX19 to the ER, and a PX domain that binds to phosphatidylinositol 3-phosphate on the endolysosomal membrane. Two other domains named PXA and PXC negatively regulate the interaction of SNX19 with endolysosomes. These studies thus identify a mechanism for controlling the motility and positioning of endolysosomes that involves tethering to the ER by a sorting nexin.
Collapse
Affiliation(s)
- Amra Saric
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Spencer A Freeman
- Program in Cell Biology, Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, Toronto, ON, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Chad D Williamson
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Michal Jarnik
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Carlos M Guardia
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Michael S Fernandopulle
- Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - David C Gershlick
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Juan S Bonifacino
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA.
| |
Collapse
|
35
|
Zapata-Muñoz J, Villarejo-Zori B, Largo-Barrientos P, Boya P. Towards a better understanding of the neuro-developmental role of autophagy in sickness and in health. Cell Stress 2021; 5:99-118. [PMID: 34308255 PMCID: PMC8283300 DOI: 10.15698/cst2021.07.253] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 05/31/2021] [Accepted: 06/02/2021] [Indexed: 01/18/2023] Open
Abstract
Autophagy is a critical cellular process by which biomolecules and cellular organelles are degraded in an orderly manner inside lysosomes. This process is particularly important in neurons: these post-mitotic cells cannot divide or be easily replaced and are therefore especially sensitive to the accumulation of toxic proteins and damaged organelles. Dysregulation of neuronal autophagy is well documented in a range of neurodegenerative diseases. However, growing evidence indicates that autophagy also critically contributes to neurodevelopmental cellular processes, including neurogenesis, maintenance of neural stem cell homeostasis, differentiation, metabolic reprogramming, and synaptic remodelling. These findings implicate autophagy in neurodevelopmental disorders. In this review we discuss the current understanding of the role of autophagy in neurodevelopment and neurodevelopmental disorders, as well as currently available tools and techniques that can be used to further investigate this association.
Collapse
Affiliation(s)
- Juan Zapata-Muñoz
- Centro de Investigaciones Biológicas Margarita Salas, CSIC, Madrid, Spain
| | | | | | - Patricia Boya
- Centro de Investigaciones Biológicas Margarita Salas, CSIC, Madrid, Spain
| |
Collapse
|
36
|
Vieira N, Rito T, Correia-Neves M, Sousa N. Sorting Out Sorting Nexins Functions in the Nervous System in Health and Disease. Mol Neurobiol 2021; 58:4070-4106. [PMID: 33931804 PMCID: PMC8280035 DOI: 10.1007/s12035-021-02388-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 04/05/2021] [Indexed: 12/18/2022]
Abstract
Endocytosis is a fundamental process that controls protein/lipid composition of the plasma membrane, thereby shaping cellular metabolism, sensing, adhesion, signaling, and nutrient uptake. Endocytosis is essential for the cell to adapt to its surrounding environment, and a tight regulation of the endocytic mechanisms is required to maintain cell function and survival. This is particularly significant in the central nervous system (CNS), where composition of neuronal cell surface is crucial for synaptic functioning. In fact, distinct pathologies of the CNS are tightly linked to abnormal endolysosomal function, and several genome wide association analysis (GWAS) and biochemical studies have identified intracellular trafficking regulators as genetic risk factors for such pathologies. The sorting nexins (SNXs) are a family of proteins involved in protein trafficking regulation and signaling. SNXs dysregulation occurs in patients with Alzheimer’s disease (AD), Down’s syndrome (DS), schizophrenia, ataxia and epilepsy, among others, establishing clear roles for this protein family in pathology. Interestingly, restoration of SNXs levels has been shown to trigger synaptic plasticity recovery in a DS mouse model. This review encompasses an historical and evolutionary overview of SNXs protein family, focusing on its organization, phyla conservation, and evolution throughout the development of the nervous system during speciation. We will also survey SNXs molecular interactions and highlight how defects on SNXs underlie distinct pathologies of the CNS. Ultimately, we discuss possible strategies of intervention, surveying how our knowledge about the fundamental processes regulated by SNXs can be applied to the identification of novel therapeutic avenues for SNXs-related disorders.
Collapse
Affiliation(s)
- Neide Vieira
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057, Braga, Portugal. .,ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal.
| | - Teresa Rito
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057, Braga, Portugal.,ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Margarida Correia-Neves
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057, Braga, Portugal.,ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Nuno Sousa
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057, Braga, Portugal.,ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| |
Collapse
|
37
|
Zebrafish Models of Autosomal Recessive Ataxias. Cells 2021; 10:cells10040836. [PMID: 33917666 PMCID: PMC8068028 DOI: 10.3390/cells10040836] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 04/01/2021] [Accepted: 04/06/2021] [Indexed: 12/11/2022] Open
Abstract
Autosomal recessive ataxias are much less well studied than autosomal dominant ataxias and there are no clearly defined systems to classify them. Autosomal recessive ataxias, which are characterized by neuronal and multisystemic features, have significant overlapping symptoms with other complex multisystemic recessive disorders. The generation of animal models of neurodegenerative disorders increases our knowledge of their cellular and molecular mechanisms and helps in the search for new therapies. Among animal models, the zebrafish, which shares 70% of its genome with humans, offer the advantages of being small in size and demonstrating rapid development, making them optimal for high throughput drug and genetic screening. Furthermore, embryo and larval transparency allows to visualize cellular processes and central nervous system development in vivo. In this review, we discuss the contributions of zebrafish models to the study of autosomal recessive ataxias characteristic phenotypes, behavior, and gene function, in addition to commenting on possible treatments found in these models. Most of the zebrafish models generated to date recapitulate the main features of recessive ataxias.
Collapse
|
38
|
Sorting nexin Mdm1/SNX14 regulates nucleolar dynamics at the NVJ after TORC1 inactivation. Biochem Biophys Res Commun 2021; 552:1-8. [PMID: 33740659 DOI: 10.1016/j.bbrc.2021.03.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 03/07/2021] [Indexed: 11/20/2022]
Abstract
The degradation of nucleolar proteins - nucleophagy - is elicited by nutrient starvation or the inactivation of target of rapamycin complex 1 (TORC1) protein kinase in budding yeast. Prior to nucleophagy, nucleolar proteins migrate to the nucleus-vacuole junction (NVJ), where micronucleophagy occurs, whereas rDNA (rRNA gene) repeat regions are condensed and escape towards NVJ-distal sites. This suggests that the NVJ controls nucleolar dynamics from outside of the nucleus after TORC1 inactivation, but its molecular mechanism is unclear. Here, we show that sorting nexin (SNX) Mdm1, an inter-organelle tethering protein at the NVJ, mediates TORC1 inactivation-induced nucleolar dynamics. Furthermore, Mdm1 was required for proper nucleophagic degradation of nucleolar proteins after TORC1 inactivation, where it was dispensable for the induction of nucleophagic flux itself. This indicated that nucleophagy and nucleolar dynamics are independently regulated by TORC1 inactivation. Finally, Mdm1 was critical for survival during nutrient starvation conditions. Mutations of SNX14, a human Mdm1 homolog, cause neurodevelopmental disorders. This study provides a novel insight into relationship between sorting nexin-mediated microautophagy and neurodevelopmental disorders.
Collapse
|
39
|
Amatya B, Lee H, Asico LD, Konkalmatt P, Armando I, Felder RA, Jose PA. SNX-PXA-RGS-PXC Subfamily of SNXs in the Regulation of Receptor-Mediated Signaling and Membrane Trafficking. Int J Mol Sci 2021; 22:ijms22052319. [PMID: 33652569 PMCID: PMC7956473 DOI: 10.3390/ijms22052319] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 02/13/2021] [Accepted: 02/22/2021] [Indexed: 12/26/2022] Open
Abstract
The SNX-PXA-RGS-PXC subfamily of sorting nexins (SNXs) belongs to the superfamily of SNX proteins. SNXs are characterized by the presence of a common phox-homology (PX) domain, along with other functional domains that play versatile roles in cellular signaling and membrane trafficking. In addition to the PX domain, the SNX-PXA-RGS-PXC subfamily, except for SNX19, contains a unique RGS (regulators of G protein signaling) domain that serves as GTPase activating proteins (GAPs), which accelerates GTP hydrolysis on the G protein α subunit, resulting in termination of G protein-coupled receptor (GPCR) signaling. Moreover, the PX domain selectively interacts with phosphatidylinositol-3-phosphate and other phosphoinositides found in endosomal membranes, while also associating with various intracellular proteins. Although SNX19 lacks an RGS domain, all members of the SNX-PXA-RGS-PXC subfamily serve as dual regulators of receptor cargo signaling and endosomal trafficking. This review discusses the known and proposed functions of the SNX-PXA-RGS-PXC subfamily and how it participates in receptor signaling (both GPCR and non-GPCR) and endosomal-based membrane trafficking. Furthermore, we discuss the difference of this subfamily of SNXs from other subfamilies, such as SNX-BAR nexins (Bin-Amphiphysin-Rvs) that are associated with retromer or other retrieval complexes for the regulation of receptor signaling and membrane trafficking. Emerging evidence has shown that the dysregulation and malfunction of this subfamily of sorting nexins lead to various pathophysiological processes and disorders, including hypertension.
Collapse
Affiliation(s)
- Bibhas Amatya
- The George Washington University, Washington, DC 20052, USA;
| | - Hewang Lee
- Department of Medicine, The George Washington University School of Medicine & Health Sciences, Washington, DC 20052, USA; (H.L.); (L.D.A.); (P.K.); (I.A.)
| | - Laureano D. Asico
- Department of Medicine, The George Washington University School of Medicine & Health Sciences, Washington, DC 20052, USA; (H.L.); (L.D.A.); (P.K.); (I.A.)
| | - Prasad Konkalmatt
- Department of Medicine, The George Washington University School of Medicine & Health Sciences, Washington, DC 20052, USA; (H.L.); (L.D.A.); (P.K.); (I.A.)
| | - Ines Armando
- Department of Medicine, The George Washington University School of Medicine & Health Sciences, Washington, DC 20052, USA; (H.L.); (L.D.A.); (P.K.); (I.A.)
| | - Robin A. Felder
- Department of Pathology, University of Virginia Health Sciences Center, Charlottesville, VA 22908, USA;
| | - Pedro A. Jose
- Department of Medicine, The George Washington University School of Medicine & Health Sciences, Washington, DC 20052, USA; (H.L.); (L.D.A.); (P.K.); (I.A.)
- Department of Pathology, University of Virginia Health Sciences Center, Charlottesville, VA 22908, USA;
- Department of Pharmacology/Physiology, The George Washington University School of Medicine & Health Sciences, Washington, DC 20052, USA
- Correspondence:
| |
Collapse
|
40
|
Signorelli P, Pivari F, Barcella M, Merelli I, Zulueta A, Dei Cas M, Rosso L, Ghidoni R, Caretti A, Paroni R, Mingione A. Myriocin modulates the altered lipid metabolism and storage in cystic fibrosis. Cell Signal 2021; 81:109928. [PMID: 33482299 DOI: 10.1016/j.cellsig.2021.109928] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 01/13/2021] [Accepted: 01/13/2021] [Indexed: 12/12/2022]
Abstract
Cystic fibrosis (CF) is a hereditary disease mostly related to ΔF508 CFTR mutation causing a proteinopathy that is characterized by multiple organ dysfunction, primarily lungs chronic inflammation, and infection. Defective autophagy and accumulation of the inflammatory lipid ceramide have been proposed as therapeutic targets. Accumulation of lipids and cholesterol was reported in the airways of CF patients, together with altered triglycerides and cholesterol levels in plasma, thus suggesting a disease-related dyslipidemia. Myriocin, an inhibitor of sphingolipids synthesis, significantly reduces inflammation and activates TFEB-induced response to stress, enhancing fatty acids oxidation and promoting autophagy. Myriocin ameliorates the response against microbial infection in CF models and patients' monocytes. Here we show that CF broncho-epithelial cells exhibit an altered distribution of intracellular lipids. We demonstrated that lipid accumulation is supported by an enhanced synthesis of fatty acids containing molecules and that Myriocin is able to reduce such accumulation. Moreover, Myriocin modulated the transcriptional profile of CF cells in order to restore autophagy, activate an anti-oxidative response, stimulate lipid metabolism and reduce lipid peroxidation. Moreover, lipid storage may be altered in CF cells, since we observed a reduced expression of lipid droplets related proteins named perilipin 3 and 5 and seipin. To note, Myriocin up-regulates the expression of genes that are involved in lipid droplets biosynthesis and maturation. We suggest that targeting sphingolipids de novo synthesis may counteract lipids accumulation by modulating CF altered transcriptional profile, thus restoring autophagy and lipid metabolism homeostasis.
Collapse
Affiliation(s)
- Paola Signorelli
- Biochemistry and Molecular Biology Laboratory, Department of Health Science, University of Milan, Milan, Italy; "Aldo Ravelli" Center for Neurotechnology and Experimental Brain Therapeutics, University of Milan, Milan, Italy
| | - Francesca Pivari
- Biochemistry and Molecular Biology Laboratory, Department of Health Science, University of Milan, Milan, Italy
| | - Matteo Barcella
- Department of Health Sciences, University of Milan, Milan, Italy
| | - Ivan Merelli
- Institute for Biomedical Technologies, National Research Council of Italy, Milan, Italy
| | - Aida Zulueta
- Biochemistry and Molecular Biology Laboratory, Department of Health Science, University of Milan, Milan, Italy
| | - Michele Dei Cas
- Laboratory of Clinical Biochemistry and Mass Spectrometry, Department of Health Sciences, University of Milan, Milan, Italy
| | - Lorenzo Rosso
- Thoracic surgery and transplantation Unit, Fondazione IRCCS Ca Granda Ospedale Maggiore Policlinico, Health Sciences Department, University of Milan, Milan, Italy
| | - Riccardo Ghidoni
- Biochemistry and Molecular Biology Laboratory, Department of Health Science, University of Milan, Milan, Italy; "Aldo Ravelli" Center for Neurotechnology and Experimental Brain Therapeutics, University of Milan, Milan, Italy
| | - Anna Caretti
- Biochemistry and Molecular Biology Laboratory, Department of Health Science, University of Milan, Milan, Italy
| | - Rita Paroni
- Laboratory of Clinical Biochemistry and Mass Spectrometry, Department of Health Sciences, University of Milan, Milan, Italy
| | - Alessandra Mingione
- Biochemistry and Molecular Biology Laboratory, Department of Health Science, University of Milan, Milan, Italy; "Aldo Ravelli" Center for Neurotechnology and Experimental Brain Therapeutics, University of Milan, Milan, Italy.
| |
Collapse
|
41
|
Duan X, Tong C. Autophagy in Drosophila and Zebrafish. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1208:333-356. [PMID: 34260032 DOI: 10.1007/978-981-16-2830-6_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Autophagy is a highly conserved cellular process that delivers cellular contents to the lysosome for degradation. It not only serves as a bulk degradation system for various cytoplasmic components but also functions selectively to clear damaged organelles, aggregated proteins, and invading pathogens (Feng et al., Cell Res 24:24-41, 2014; Galluzzi et al., EMBO J 36:1811-36, 2017; Klionsky et al., Autophagy 12:1-222, 2016). The malfunction of autophagy leads to multiple developmental defects and diseases (Mizushima et al., Nature 451:1069-75, 2008). Drosophila and zebrafish are higher metazoan model systems with sophisticated genetic tools readily available, which make it possible to dissect the autophagic processes and to understand the physiological functions of autophagy (Lorincz et al., Cells 6:22, 2017a; Mathai et al., Cells 6:21, 2017; Zhang and Baehrecke, Trends Cell Biol 25:376-87, 2015). In this chapter, we will discuss recent progress that has been made in the autophagic field by using these animal models. We will focus on the protein machineries required for autophagosome formation and maturation as well as the physiological roles of autophagy in both Drosophila and zebrafish.
Collapse
Affiliation(s)
- Xiuying Duan
- MOE Key Laboratory for Biosystems Homeostasis and Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang, China
| | - Chao Tong
- MOE Key Laboratory for Biosystems Homeostasis and Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang, China. .,The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
| |
Collapse
|
42
|
Snx14 proximity labeling reveals a role in saturated fatty acid metabolism and ER homeostasis defective in SCAR20 disease. Proc Natl Acad Sci U S A 2020; 117:33282-33294. [PMID: 33310904 DOI: 10.1073/pnas.2011124117] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Fatty acids (FAs) are central cellular metabolites that contribute to lipid synthesis, and can be stored or harvested for metabolic energy. Dysregulation in FA processing and storage causes toxic FA accumulation or altered membrane compositions and contributes to metabolic and neurological disorders. Saturated lipids are particularly detrimental to cells, but how lipid saturation levels are maintained remains poorly understood. Here, we identify the cerebellar ataxia spinocerebellar ataxia, autosomal recessive 20 (SCAR20)-associated protein Snx14, an endoplasmic reticulum (ER)-lipid droplet (LD) tethering protein, as a factor required to maintain the lipid saturation balance of cell membranes. We show that following saturated FA (SFA) treatment, the ER integrity of SNX14 KO cells is compromised, and both SNX14 KO cells and SCAR20 disease patient-derived cells are hypersensitive to SFA-mediated lipotoxic cell death. Using APEX2-based proximity labeling, we reveal the protein composition of Snx14-associated ER-LD contacts and define a functional interaction between Snx14 and Δ-9 FA desaturase SCD1. Lipidomic profiling reveals that SNX14 KO cells increase membrane lipid saturation following exposure to palmitate, phenocopying cells with perturbed SCD1 activity. In line with this, SNX14 KO cells manifest delayed FA processing and lipotoxicity, which can be rescued by SCD1 overexpression. Altogether, these mechanistic insights reveal a role for Snx14 in FA and ER homeostasis, defects in which may underlie the neuropathology of SCAR20.
Collapse
|
43
|
Maia N, Soares G, Silva C, Marques I, Rodrigues B, Santos R, Melo-Pires M, de Brouwer APM, Temudo T, Jorge P. Two Compound Heterozygous Variants in SNX14 Cause Stereotypies and Dystonia in Autosomal Recessive Spinocerebellar Ataxia 20. Front Genet 2020; 11:1038. [PMID: 33193593 PMCID: PMC7543990 DOI: 10.3389/fgene.2020.01038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 08/11/2020] [Indexed: 11/13/2022] Open
Abstract
Autosomal Recessive Spinocerebellar Ataxia 20, SCAR20, is a rare condition characterized by intellectual disability, lack of speech, ataxia, coarse facies and macrocephaly, caused by SNX14 variants. While all cases described are due to homozygous variants that generally result in loss of protein, so far there are no other cases of reported compound heterozygous variants. Here we describe the first non-consanguineous SCAR20 family, the second Portuguese, with two siblings presenting similar clinical features caused by compound heterozygous SNX14 variants: NM_001350532.1:c.1195C>T, p.(Arg399*) combined with a novel complex genomic rearrangement. Quantitative PCR (Q-PCR), long-range PCR and sequencing was used to elucidate the region and mechanisms involved in the latter: two deletions, an inversion and an AG insertion: NM_001350532.1:c.[612+3028_698-2759del;698-2758_698-516inv;698-515_1171+1366delinsAG]. In silico analyses of these variants are in agreement with causality, enabling a genotype-phenotype correlation in both patients. Clinical phenotype includes dystonia and stereotypies never associated with SCAR20. Overall, this study allowed to extend the knowledge of the phenotypic and mutational spectrum of SCAR20, and to validate the role of Sorting nexin-14 in a well-defined neurodevelopmental syndrome, which can lead to cognitive impairment. We also highlight the value of an accurate clinical evaluation and deep phenotyping to disclose the molecular defect underlying highly heterogeneous condition such as intellectual disability.
Collapse
Affiliation(s)
- Nuno Maia
- Unidade de Genética Molecular, Centro de Genética Médica Jacinto de Magalhães (CGM), Centro Hospitalar Universitário do Porto (CHUP), Porto, Portugal
- Unidade Multidisciplinar de Investigação Biomédica (UMIB), Instituto de Ciências Biomédicas Abel Salazar (ICBAS), Universidade do Porto, Porto, Portugal
| | - Gabriela Soares
- Unidade de Genética Médica, Centro de Genética Médica Jacinto de Magalhães (CGM), Centro Hospitalar Universitário do Porto (CHUP), Porto, Portugal
| | - Cecília Silva
- Unidade de Genética Molecular, Centro de Genética Médica Jacinto de Magalhães (CGM), Centro Hospitalar Universitário do Porto (CHUP), Porto, Portugal
- Unidade Multidisciplinar de Investigação Biomédica (UMIB), Instituto de Ciências Biomédicas Abel Salazar (ICBAS), Universidade do Porto, Porto, Portugal
| | - Isabel Marques
- Unidade de Genética Molecular, Centro de Genética Médica Jacinto de Magalhães (CGM), Centro Hospitalar Universitário do Porto (CHUP), Porto, Portugal
- Unidade Multidisciplinar de Investigação Biomédica (UMIB), Instituto de Ciências Biomédicas Abel Salazar (ICBAS), Universidade do Porto, Porto, Portugal
| | - Bárbara Rodrigues
- Unidade de Genética Molecular, Centro de Genética Médica Jacinto de Magalhães (CGM), Centro Hospitalar Universitário do Porto (CHUP), Porto, Portugal
- Unidade Multidisciplinar de Investigação Biomédica (UMIB), Instituto de Ciências Biomédicas Abel Salazar (ICBAS), Universidade do Porto, Porto, Portugal
| | - Rosário Santos
- Unidade de Genética Molecular, Centro de Genética Médica Jacinto de Magalhães (CGM), Centro Hospitalar Universitário do Porto (CHUP), Porto, Portugal
- Unidade Multidisciplinar de Investigação Biomédica (UMIB), Instituto de Ciências Biomédicas Abel Salazar (ICBAS), Universidade do Porto, Porto, Portugal
| | - Manuel Melo-Pires
- Serviço de Neuropatologia, Centro Hospitalar Universitário do Porto (CHUP), Porto, Portugal
| | - Arjan PM de Brouwer
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, Netherlands
| | - Teresa Temudo
- Serviço de Neurologia Pediátrica, Centro Hospitalar Universitário do Porto (CHUP), Porto, Portugal
| | - Paula Jorge
- Unidade de Genética Molecular, Centro de Genética Médica Jacinto de Magalhães (CGM), Centro Hospitalar Universitário do Porto (CHUP), Porto, Portugal
- Unidade Multidisciplinar de Investigação Biomédica (UMIB), Instituto de Ciências Biomédicas Abel Salazar (ICBAS), Universidade do Porto, Porto, Portugal
| |
Collapse
|
44
|
Autophagy in Neuronal Development and Plasticity. Trends Neurosci 2020; 43:767-779. [PMID: 32800535 DOI: 10.1016/j.tins.2020.07.003] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 06/03/2020] [Accepted: 07/09/2020] [Indexed: 01/05/2023]
Abstract
Autophagy is a highly conserved intracellular clearance pathway in which cytoplasmic contents are trafficked to the lysosome for degradation. Within neurons, it helps to remove damaged organelles and misfolded or aggregated proteins and has therefore been the subject of intense research in relation to neurodegenerative disease. However, far less is understood about the role of autophagy in other aspects of neuronal physiology. Here we review the literature on the role of autophagy in maintaining neuronal stem cells and in neuronal plasticity in adult life and we discuss how these contribute to structural and functional deficits observed in a range of human disorders.
Collapse
|
45
|
Diverse species-specific phenotypic consequences of loss of function sorting nexin 14 mutations. Sci Rep 2020; 10:13763. [PMID: 32792680 PMCID: PMC7427099 DOI: 10.1038/s41598-020-70797-2] [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: 11/15/2019] [Accepted: 08/05/2020] [Indexed: 11/08/2022] Open
Abstract
Mutations in the SNX14 gene cause spinocerebellar ataxia, autosomal recessive 20 (SCAR20) in both humans and dogs. Studies implicating the phenotypic consequences of SNX14 mutations to be consequences of subcellular disruption to autophagy and lipid metabolism have been limited to in vitro investigation of patient-derived dermal fibroblasts, laboratory engineered cell lines and developmental analysis of zebrafish morphants. SNX14 homologues Snz (Drosophila) and Mdm1 (yeast) have also been conducted, demonstrated an important biochemical role during lipid biogenesis. In this study we report the effect of loss of SNX14 in mice, which resulted in embryonic lethality around mid-gestation due to placental pathology that involves severe disruption to syncytiotrophoblast cell differentiation. In contrast to other vertebrates, zebrafish carrying a homozygous, maternal zygotic snx14 genetic loss-of-function mutation were both viable and anatomically normal. Whilst no obvious behavioural effects were observed, elevated levels of neutral lipids and phospholipids resemble previously reported effects on lipid homeostasis in other species. The biochemical role of SNX14 therefore appears largely conserved through evolution while the consequences of loss of function varies between species. Mouse and zebrafish models therefore provide valuable insights into the functional importance of SNX14 with distinct opportunities for investigating its cellular and metabolic function in vivo.
Collapse
|
46
|
Mingione A, Ottaviano E, Barcella M, Merelli I, Rosso L, Armeni T, Cirilli N, Ghidoni R, Borghi E, Signorelli P. Cystic Fibrosis Defective Response to Infection Involves Autophagy and Lipid Metabolism. Cells 2020; 9:cells9081845. [PMID: 32781626 PMCID: PMC7463682 DOI: 10.3390/cells9081845] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/31/2020] [Accepted: 08/04/2020] [Indexed: 12/14/2022] Open
Abstract
Cystic fibrosis (CF) is a hereditary disease, with 70% of patients developing a proteinopathy related to the deletion of phenylalanine 508. CF is associated with multiple organ dysfunction, chronic inflammation, and recurrent lung infections. CF is characterized by defective autophagy, lipid metabolism, and immune response. Intracellular lipid accumulation favors microbial infection, and autophagy deficiency impairs internalized pathogen clearance. Myriocin, an inhibitor of sphingolipid synthesis, significantly reduces inflammation, promotes microbial clearance in the lungs, and induces autophagy and lipid oxidation. RNA-seq was performed in Aspergillusfumigatus-infected and myriocin-treated CF patients’ derived monocytes and in a CF bronchial epithelial cell line. Fungal clearance was also evaluated in CF monocytes. Myriocin enhanced CF patients’ monocytes killing of A. fumigatus. CF patients’ monocytes and cell line responded to infection with a profound transcriptional change; myriocin regulates genes that are involved in inflammation, autophagy, lipid storage, and metabolism, including histones and heat shock proteins whose activity is related to the response to infection. We conclude that the regulation of sphingolipid synthesis induces a metabolism drift by promoting autophagy and lipid consumption. This process is driven by a transcriptional program that corrects part of the differences between CF and control samples, therefore ameliorating the infection response and pathogen clearance in the CF cell line and in CF peripheral blood monocytes.
Collapse
Affiliation(s)
- Alessandra Mingione
- Biochemistry and Molecular Biology Laboratory, Health Science Department, University of Milan, San Paolo Hospital, 20142 Milan, Italy; (A.M.); (R.G.)
| | - Emerenziana Ottaviano
- Laboratory of Clinical Microbiology, Health Science Department, University of Milan, San Paolo Hospital, 20142 Milan, Italy; (E.O.); (M.B.); (E.B.)
| | - Matteo Barcella
- Laboratory of Clinical Microbiology, Health Science Department, University of Milan, San Paolo Hospital, 20142 Milan, Italy; (E.O.); (M.B.); (E.B.)
| | - Ivan Merelli
- National Research Council of Italy, Institute for Biomedical Technologies, Via Fratelli Cervi 93, 20090 Milan, Italy;
| | - Lorenzo Rosso
- Health Sciences Department, University of Milan, Thoracic surgery and transplantation Unit, Fondazione IRCCS Ca Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy;
| | - Tatiana Armeni
- Department of Clinical Sciences, Section of Biochemistry, Biology and Physics, Polytechnic University of Marche, 60131 Ancona, Italy;
| | - Natalia Cirilli
- Cystic Fibrosis Referral Care Center, Mother-Child Department, United Hospitals Le Torrette, 60126 Ancona, Italy;
| | - Riccardo Ghidoni
- Biochemistry and Molecular Biology Laboratory, Health Science Department, University of Milan, San Paolo Hospital, 20142 Milan, Italy; (A.M.); (R.G.)
- “Aldo Ravelli” Center for Neurotechnology and Experimental Brain Therapeutics, via Antonio di Rudinì 8, 20142 Milan, Italy
| | - Elisa Borghi
- Laboratory of Clinical Microbiology, Health Science Department, University of Milan, San Paolo Hospital, 20142 Milan, Italy; (E.O.); (M.B.); (E.B.)
| | - Paola Signorelli
- Biochemistry and Molecular Biology Laboratory, Health Science Department, University of Milan, San Paolo Hospital, 20142 Milan, Italy; (A.M.); (R.G.)
- Correspondence:
| |
Collapse
|
47
|
Targeting the Early Endosome-to-Golgi Transport of Shiga Toxins as a Therapeutic Strategy. Toxins (Basel) 2020; 12:toxins12050342. [PMID: 32456007 PMCID: PMC7290323 DOI: 10.3390/toxins12050342] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 05/19/2020] [Accepted: 05/20/2020] [Indexed: 02/07/2023] Open
Abstract
Shiga toxin (STx) produced by Shigella and closely related Shiga toxin 1 and 2 (STx1 and STx2) synthesized by Shiga toxin-producing Escherichia coli (STEC) are bacterial AB5 toxins. All three toxins target kidney cells and may cause life-threatening renal disease. While Shigella infections can be treated with antibiotics, resistance is increasing. Moreover, antibiotic therapy is contraindicated for STEC, and there are no definitive treatments for STEC-induced disease. To exert cellular toxicity, STx, STx1, and STx2 must undergo retrograde trafficking to reach their cytosolic target, ribosomes. Direct transport from early endosomes to the Golgi apparatus is an essential step that allows the toxins to bypass degradative late endosomes and lysosomes. The essentiality of this transport step also makes it an ideal target for the development of small-molecule inhibitors of toxin trafficking as potential therapeutics. Here, we review the recent advances in understanding the molecular mechanisms of the early endosome-to-Golgi transport of STx, STx1, and STx2, as well as the development of small-molecule inhibitors of toxin trafficking that act at the endosome/Golgi interface.
Collapse
|
48
|
Stamatakou E, Wróbel L, Hill SM, Puri C, Son SM, Fujimaki M, Zhu Y, Siddiqi F, Fernandez-Estevez M, Manni MM, Park SJ, Villeneuve J, Rubinsztein DC. Mendelian neurodegenerative disease genes involved in autophagy. Cell Discov 2020; 6:24. [PMID: 32377374 PMCID: PMC7198619 DOI: 10.1038/s41421-020-0158-y] [Citation(s) in RCA: 25] [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: 09/30/2019] [Accepted: 03/11/2020] [Indexed: 12/13/2022] Open
Abstract
The lysosomal degradation pathway of macroautophagy (herein referred to as autophagy) plays a crucial role in cellular physiology by regulating the removal of unwanted cargoes such as protein aggregates and damaged organelles. Over the last five decades, significant progress has been made in understanding the molecular mechanisms that regulate autophagy and its roles in human physiology and diseases. These advances, together with discoveries in human genetics linking autophagy-related gene mutations to specific diseases, provide a better understanding of the mechanisms by which autophagy-dependent pathways can be potentially targeted for treating human diseases. Here, we review mutations that have been identified in genes involved in autophagy and their associations with neurodegenerative diseases.
Collapse
Affiliation(s)
- Eleanna Stamatakou
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - Lidia Wróbel
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - Sandra Malmgren Hill
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - Claudia Puri
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - Sung Min Son
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - Motoki Fujimaki
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - Ye Zhu
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - Farah Siddiqi
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - Marian Fernandez-Estevez
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - Marco M. Manni
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - So Jung Park
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - Julien Villeneuve
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - David Chaim Rubinsztein
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| |
Collapse
|
49
|
Fassio A, Falace A, Esposito A, Aprile D, Guerrini R, Benfenati F. Emerging Role of the Autophagy/Lysosomal Degradative Pathway in Neurodevelopmental Disorders With Epilepsy. Front Cell Neurosci 2020; 14:39. [PMID: 32231521 PMCID: PMC7082311 DOI: 10.3389/fncel.2020.00039] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 02/10/2020] [Indexed: 01/08/2023] Open
Abstract
Autophagy is a highly conserved degradative process that conveys dysfunctional proteins, lipids, and organelles to lysosomes for degradation. The post-mitotic nature, complex and highly polarized morphology, and high degree of specialization of neurons make an efficient autophagy essential for their homeostasis and survival. Dysfunctional autophagy occurs in aging and neurodegenerative diseases, and autophagy at synaptic sites seems to play a crucial role in neurodegeneration. Moreover, a role of autophagy is emerging for neural development, synaptogenesis, and the establishment of a correct connectivity. Thus, it is not surprising that defective autophagy has been demonstrated in a spectrum of neurodevelopmental disorders, often associated with early-onset epilepsy. Here, we discuss the multiple roles of autophagy in neurons and the recent experimental evidence linking neurodevelopmental disorders with epilepsy to genes coding for autophagic/lysosomal system-related proteins and envisage possible pathophysiological mechanisms ranging from synaptic dysfunction to neuronal death.
Collapse
Affiliation(s)
- Anna Fassio
- Department of Experimental Medicine, University of Genoa, Genoa, Italy.,IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | - Antonio Falace
- Pediatric Neurology, Neurogenetics and Neurobiology Unit and Laboratories, Children's Hospital A. Meyer-University of Florence, Florence, Italy
| | - Alessandro Esposito
- Department of Experimental Medicine, University of Genoa, Genoa, Italy.,Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Davide Aprile
- Department of Experimental Medicine, University of Genoa, Genoa, Italy.,Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Renzo Guerrini
- Pediatric Neurology, Neurogenetics and Neurobiology Unit and Laboratories, Children's Hospital A. Meyer-University of Florence, Florence, Italy.,IRCCS Fondazione Stella Maris, Pisa, Italy
| | - Fabio Benfenati
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy.,Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Genoa, Italy
| |
Collapse
|
50
|
Darios F, Stevanin G. Impairment of Lysosome Function and Autophagy in Rare Neurodegenerative Diseases. J Mol Biol 2020; 432:2714-2734. [PMID: 32145221 PMCID: PMC7232018 DOI: 10.1016/j.jmb.2020.02.033] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 02/28/2020] [Accepted: 02/28/2020] [Indexed: 02/07/2023]
Abstract
Rare genetic diseases affect a limited number of patients, but their etiology is often known, facilitating the development of reliable animal models and giving the opportunity to investigate physiopathology. Lysosomal storage disorders are a group of rare diseases due to primary alteration of lysosome function. These diseases are often associated with neurological symptoms, which highlighted the importance of lysosome in neurodegeneration. Likewise, other groups of rare neurodegenerative diseases also present lysosomal alteration. Lysosomes fuse with autophagosomes and endosomes to allow the degradation of their content thanks to hydrolytic enzymes. It has emerged that alteration of the autophagy–lysosome pathway could play a critical role in neuronal death in many neurodegenerative diseases. Using a repertoire of selected rare neurodegenerative diseases, we highlight that a variety of alterations of the autophagy–lysosome pathway are associated with neuronal death. Yet, in most cases, it is still unclear why alteration of this pathway can lead to neurodegeneration. Lysosome function is impaired in many rare neurodegenerative diseases, making it a convergent point for these diseases. Impaired lysosome function is associated with alteration of the autophagy pathway. Autophagy–lysosome pathway can be impaired at various steps in different rare neurodegenerative diseases. The mechanisms linking impaired autophagy–lysosome pathway to neurodegeneration are still not fully elucidated.
Collapse
Affiliation(s)
- Frédéric Darios
- Sorbonne Université, F-75013, Paris, France; Inserm, U1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Institut du Cerveau et de la Moelle Epinière, ICM, F-75013 Paris, France.
| | - Giovanni Stevanin
- Sorbonne Université, F-75013, Paris, France; Inserm, U1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Institut du Cerveau et de la Moelle Epinière, ICM, F-75013 Paris, France; PSL Research University, Ecole Pratique des Hautes Etudes, Laboratoire de Neurogénétique, F-75013 Paris, France
| |
Collapse
|