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Hu D, Li Y, Wang X, Zou H, Li Z, Chen W, Meng Y, Wang Y, Li Q, Liao F, Wu K, Wu J, Li G, Wang W. Palmitoylation of NLRP3 Modulates Inflammasome Activation and Inflammatory Bowel Disease Development. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2024; 213:481-493. [PMID: 38949555 PMCID: PMC11299489 DOI: 10.4049/jimmunol.2300241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 06/07/2024] [Indexed: 07/02/2024]
Abstract
Aberrant activity of NLRP3 has been shown associations with severe diseases. Palmitoylation is a kind of protein post-translational modification, which has been shown to regulate cancer development and the innate immune system. Here, we showed that NLRP3 is palmitoylated at Cys419 and that palmitoyltransferase ZDHHC17 is the predominant enzyme that mediates NLRP3 palmitoylation and promotes NLRP3 activation by interacting with NLRP3 and facilitating NIMA-related kinase 7 (NEK7)-NLRP3 interactions. Blockade of NLRP3 palmitoylation by a palmitoylation inhibitor, 2-bromopalmitate, effectively inhibited NLRP3 activation in vitro. Also, in a dextran sulfate sodium-induced colitis model in mice, 2-bromopalmitate application could attenuate weight loss, improve the survival rate, and rescue pathological changes in the colon of mice. Overall, our study reveals that palmitoylation of NLPR3 modulates inflammasome activation and inflammatory bowel disease development. We propose that drugs targeting NLRP3 palmitoylation could be promising candidates in the treatment of NLRP3-mediated inflammatory diseases.
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Affiliation(s)
- Dingwen Hu
- Clinical Experimental Center, Jiangmen Central Hospital, Jiangmen, China
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yuting Li
- Laboratory Animal Center, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Xianyang Wang
- Laboratory Animal Center, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Haimei Zou
- Laboratory Animal Center, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Zonghui Li
- Laboratory Animal Center, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Weijie Chen
- Guangdong Provincial Key Laboratory of Virology, Institute of Medical Microbiology, Jinan University, Guangzhou, China
| | - Yu Meng
- Laboratory Animal Center, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yingchong Wang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Qin Li
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Feng Liao
- Laboratory Animal Center, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Kailang Wu
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Jianguo Wu
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
- Guangdong Provincial Key Laboratory of Virology, Institute of Medical Microbiology, Jinan University, Guangzhou, China
| | - Geng Li
- Laboratory Animal Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Guangdong Provincial Key Laboratory of Virology, Institute of Medical Microbiology, Jinan University, Guangzhou, China
| | - Wenbiao Wang
- Medical Research Institute, Guangdong Provincial People’s Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, China
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Zhang X, Jeong H, Niu J, Holland SM, Rotanz BN, Gordon J, Einarson MB, Childers WE, Thomas GM. Novel inhibitors of acute, axonal DLK palmitoylation are neuroprotective and avoid the deleterious side effects of cell-wide DLK inhibition. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.19.590310. [PMID: 38712276 PMCID: PMC11071345 DOI: 10.1101/2024.04.19.590310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Dual leucine-zipper kinase (DLK) drives acute and chronic forms of neurodegeneration, suggesting that inhibiting DLK signaling could ameliorate diverse neuropathological conditions. However, direct inhibition of DLK's kinase domain in human patients and conditional knockout of DLK in mice both cause unintended side effects, including elevated plasma neurofilament levels, indicative of neuronal cytoskeletal disruption. Indeed, we found that a DLK kinase domain inhibitor acutely disrupted the axonal cytoskeleton and caused vesicle aggregation in cultured dorsal root ganglion (DRG) neurons, further cautioning against this therapeutic strategy. In seeking a more precise intervention, we found that retrograde (axon-to-soma) pro-degenerative signaling requires acute, axonal palmitoylation of DLK and hypothesized that modulating this post-translational modification might be more specifically neuroprotective than cell-wide DLK inhibition. To address this possibility, we screened >28,000 compounds using a high-content imaging assay that quantitatively evaluates DLK's palmitoylation-dependent subcellular localization. Of the 33 hits that significantly altered DLK localization in non-neuronal cells, several reduced DLK retrograde signaling and protected cultured DRG neurons from DLK-dependent neurodegeneration. Mechanistically, the two most neuroprotective compounds selectively prevent stimulus-dependent palmitoylation of axonal pools of DLK, a process crucial for DLK's recruitment to axonal vesicles. In contrast, these compounds minimally impact DLK localization and signaling in healthy neurons and avoid the cytoskeletal disruption associated with direct DLK inhibition. Importantly, our hit compounds also reduce pro-degenerative retrograde signaling in vivo, suggesting that modulating DLK's palmitoylation-dependent localization could be a novel neuroprotective strategy.
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Köster KA, Dethlefs M, Duque Escobar J, Oetjen E. Regulation of the Activity of the Dual Leucine Zipper Kinase by Distinct Mechanisms. Cells 2024; 13:333. [PMID: 38391946 PMCID: PMC10886912 DOI: 10.3390/cells13040333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 02/05/2024] [Accepted: 02/07/2024] [Indexed: 02/24/2024] Open
Abstract
The dual leucine zipper kinase (DLK) alias mitogen-activated protein 3 kinase 12 (MAP3K12) has gained much attention in recent years. DLK belongs to the mixed lineage kinases, characterized by homology to serine/threonine and tyrosine kinase, but exerts serine/threonine kinase activity. DLK has been implicated in many diseases, including several neurodegenerative diseases, glaucoma, and diabetes mellitus. As a MAP3K, it is generally assumed that DLK becomes phosphorylated and activated by upstream signals and phosphorylates and activates itself, the downstream serine/threonine MAP2K, and, ultimately, MAPK. In addition, other mechanisms such as protein-protein interactions, proteasomal degradation, dephosphorylation by various phosphatases, palmitoylation, and subcellular localization have been shown to be involved in the regulation of DLK activity or its fine-tuning. In the present review, the diverse mechanisms regulating DLK activity will be summarized to provide better insights into DLK action and, possibly, new targets to modulate DLK function.
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Affiliation(s)
- Kyra-Alexandra Köster
- Department of Clinical Pharmacology and Toxicology, University Medical Centre Hamburg-Eppendorf, 20246 Hamburg, Germany; (K.-A.K.); (M.D.)
- DZHK Standort Hamburg, Kiel, Lübeck, Germany;
| | - Marten Dethlefs
- Department of Clinical Pharmacology and Toxicology, University Medical Centre Hamburg-Eppendorf, 20246 Hamburg, Germany; (K.-A.K.); (M.D.)
- DZHK Standort Hamburg, Kiel, Lübeck, Germany;
| | - Jorge Duque Escobar
- DZHK Standort Hamburg, Kiel, Lübeck, Germany;
- University Center of Cardiovascular Science, Department of Cardiology, University Heart & Vascular Center Hamburg, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Elke Oetjen
- Department of Clinical Pharmacology and Toxicology, University Medical Centre Hamburg-Eppendorf, 20246 Hamburg, Germany; (K.-A.K.); (M.D.)
- DZHK Standort Hamburg, Kiel, Lübeck, Germany;
- Institute of Pharmacy, University of Hamburg, 20146 Hamburg, Germany
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Kim S, Quagraine Y, Singh M, Kim JH. Rab11 suppresses neuronal stress signaling by localizing Dual leucine zipper kinase to axon terminals for protein turnover. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.04.18.537392. [PMID: 37131782 PMCID: PMC10153120 DOI: 10.1101/2023.04.18.537392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Dual Leucine Zipper Kinase (DLK) mediates multiple neuronal stress responses, and its expression levels are constantly suppressed to prevent excessive stress signaling. We found that Wallenda (Wnd), the Drosophila ortholog of DLK, is highly enriched in the axon terminals of Drosophila sensory neurons in vivo and that this subcellular localization is necessary for Highwire-mediated Wnd protein turnover under normal conditions. Our structure-function analysis found that Wnd palmitoylation is essential for its axon terminal localization. Palmitoylation-defective Wnd accumulated in neuronal cell bodies, exhibited dramatically increased protein expression levels, and triggered excessive neuronal stress responses. Defective intracellular transport is implicated in neurodegenerative conditions. Comprehensive dominant-negative Rab protein screening identified Rab11 as an essential factor for Wnd localization in axon terminals. Consequently, Rab11 loss-of-function increased the protein levels of Wnd and induced neuronal stress responses. Inhibiting Wnd activity significantly ameliorated neuronal loss and c-Jun N-terminal kinase signaling triggered by Rab11 loss-of-function. Taken together, these suggest that DLK proteins are constantly transported to axon terminals by Rab11 for protein turnover. Our study demonstrates how subcellular protein localization is coupled to protein turnover for neuronal stress signaling. Highlights Wnd is highly enriched in axon terminals.Wnd protein turnover by Hiw is restricted in the axon terminals.Protein palmitoylation of Wnd and Rab11 activity is essential for Wnd axonal localization. Rab11 mutations and defective Wnd palmitoylation impair Wnd protein turnover leading to increased Wnd protein levels and neuronal loss. Inhibiting Wnd activity mitigates neuronal stress response caused by Rab11 loss-of-function.
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Liao D, Huang Y, Liu D, Zhang H, Shi X, Li X, Luo P. The role of s-palmitoylation in neurological diseases: implication for zDHHC family. Front Pharmacol 2024; 14:1342830. [PMID: 38293675 PMCID: PMC10824933 DOI: 10.3389/fphar.2023.1342830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 12/31/2023] [Indexed: 02/01/2024] Open
Abstract
S-palmitoylation is a reversible posttranslational modification, and the palmitoylation reaction in human-derived cells is mediated by the zDHHC family, which is composed of S-acyltransferase enzymes that possess the DHHC (Asp-His-His-Cys) structural domain. zDHHC proteins form an autoacylation intermediate, which then attaches the fatty acid to cysteine a residue in the target protein. zDHHC proteins sublocalize in different neuronal structures and exert dif-ferential effects on neurons. In humans, many zDHHC proteins are closely related to human neu-rological disor-ders. This review focuses on a variety of neurological disorders, such as AD (Alz-heimer's disease), HD (Huntington's disease), SCZ (schizophrenia), XLID (X-linked intellectual disability), attention deficit hyperactivity disorder and glioma. In this paper, we will discuss and summarize the research progress regarding the role of zDHHC proteins in these neu-rological disorders.
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Affiliation(s)
- Dan Liao
- Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi’an, China
| | - Yutao Huang
- Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi’an, China
| | - Dan Liu
- Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi’an, China
- School of Life Science, Northwest University, Xi’an, China
| | - Haofuzi Zhang
- Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi’an, China
| | - Xinyu Shi
- Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi’an, China
| | - Xin Li
- Department of Anesthesiology, Xijing Hospital, Fourth Military Medical University, Xi’an, China
| | - Peng Luo
- Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi’an, China
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Zhao S, Ma R, Jueraitetibaike K, Xu Y, Jing J, Tang T, Shi M, Zhang H, Ge X, Chen L, Yao B, Guo Z. ZDHHC17 participates in the pathogenesis of polycystic ovary syndrome by affecting androgen conversion to estrogen in granulosa cells. Mol Cell Endocrinol 2023; 578:112076. [PMID: 37769867 DOI: 10.1016/j.mce.2023.112076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 09/23/2023] [Accepted: 09/26/2023] [Indexed: 10/03/2023]
Abstract
Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder affecting women of reproductive age and is a significant cause of female subfertility. Our previous research demonstrated that the abnormal palmitoylation of heat shock protein-90α (HSP90α) plays a role in the development of PCOS. However, the palmitoyl acyltransferases in HSP90α palmitoylation remain poorly understood. Herein, we identified ZDHHC17 as a major palmitoyl acyltransferase for HSP90α palmitoylation in granulosa cells. ZDHHC17 protein expression was diminished under excess androgen conditions in vitro and in vivo. Consistently, ovarian ZDHHC17 expression was found to be attenuated in patients with PCOS. ZDHHC17 depletion decreased HSP90α palmitoylation levels and hampered the conversion of androgen to estrogen via CYP19A1. Furthermore, ZDHHC17-mediated regulation of CYP19A1 expression was dependent on HSP90α palmitoylation. Our findings reveal that the regulatory role of HSP90α palmitoylation by ZDHHC17 is critical in PCOS pathophysiology and provide insights into the role of ZDHHC17 in reproductive endocrinology.
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Affiliation(s)
- Shanmeizi Zhao
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, Jiangsu, 210023, China; Department of Reproductive Medicine, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, 305 Zhongshan East Road, Nanjing, Jiangsu, 210002, China; Department of Reproductive Medicine, Affiliated Jinling Hospital, Nanjing Medical University, Nanjing, Jiangsu, 210002, China
| | - Rujun Ma
- Department of Reproductive Medicine, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, 305 Zhongshan East Road, Nanjing, Jiangsu, 210002, China; Department of Reproductive Medicine, Affiliated Jinling Hospital, Nanjing Medical University, Nanjing, Jiangsu, 210002, China
| | - Kadiliya Jueraitetibaike
- Department of Reproductive Medicine, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, 305 Zhongshan East Road, Nanjing, Jiangsu, 210002, China; Department of Reproductive Medicine, Affiliated Jinling Hospital, Nanjing Medical University, Nanjing, Jiangsu, 210002, China
| | - Yao Xu
- Department of Reproductive Medicine, Affiliated Jinling Hospital, Nanjing Medical University, Nanjing, Jiangsu, 210002, China; State Key Laboratory of Reproductive Medicine and Offspring Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, China
| | - Jun Jing
- Department of Reproductive Medicine, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, 305 Zhongshan East Road, Nanjing, Jiangsu, 210002, China; Department of Reproductive Medicine, Affiliated Jinling Hospital, Nanjing Medical University, Nanjing, Jiangsu, 210002, China; State Key Laboratory of Reproductive Medicine and Offspring Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, China
| | - Ting Tang
- Department of Reproductive Medicine, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, 305 Zhongshan East Road, Nanjing, Jiangsu, 210002, China
| | - Munan Shi
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, Jiangsu, 210023, China
| | - Hong Zhang
- Department of Reproductive Medicine, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, 305 Zhongshan East Road, Nanjing, Jiangsu, 210002, China
| | - Xie Ge
- Department of Reproductive Medicine, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, 305 Zhongshan East Road, Nanjing, Jiangsu, 210002, China; Department of Reproductive Medicine, Affiliated Jinling Hospital, Nanjing Medical University, Nanjing, Jiangsu, 210002, China.
| | - Li Chen
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, Jiangsu, 210023, China; Department of Reproductive Medicine, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, 305 Zhongshan East Road, Nanjing, Jiangsu, 210002, China; Department of Reproductive Medicine, Affiliated Jinling Hospital, Nanjing Medical University, Nanjing, Jiangsu, 210002, China; State Key Laboratory of Reproductive Medicine and Offspring Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, China.
| | - Bing Yao
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, Jiangsu, 210023, China; Department of Reproductive Medicine, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, 305 Zhongshan East Road, Nanjing, Jiangsu, 210002, China; Department of Reproductive Medicine, Affiliated Jinling Hospital, Nanjing Medical University, Nanjing, Jiangsu, 210002, China; State Key Laboratory of Reproductive Medicine and Offspring Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, China.
| | - Zhigang Guo
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, Jiangsu, 210023, China.
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Chen H, Zhang X, Liao N, Ji Y, Mi L, Gan Y, Su Y, Wen F. Downregulation of SIRT6 and NMNAT2 is associated with proliferative diabetic retinopathy. Mol Vis 2023; 29:160-168. [PMID: 38222451 PMCID: PMC10784219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 09/30/2023] [Indexed: 01/16/2024] Open
Abstract
Purpose To determine the expression levels of SIRT6 and NMNAT2 in diabetic retinopathy (DR). Methods We obtained peripheral blood mononuclear cells (PBMCs) and vitreous samples from 77 patients with type 2 diabetes mellitus: 52 with DR and 25 without DR, and 27 healthy control subjects. Western blot analysis and qRT-PCR were performed to evaluate the expression of SIRT6 and NMNAT2 in their PBMCs. The levels of IL-1β, IL-6, and TNF-α in the vitreous fluid were determined by ELISA. Immunohistochemistry was performed to detect the expression of SIRT6 and NMNAT2 in proliferative DR (PDR) and the control subjects. Results The expression of SIRT6 and NMNAT2 was markedly downregulated in DR patients, which was negatively correlated with the increased expression of IL-1β, IL-6 and TNF-α. Additionally, we observed decreased expression of SIRT6 and NMNAT2 in the fibrovascular membranes of PDR patients. Conclusions The downregulated expression of SIRT6 and NMNAT2 in PDR patients reveals a potential pathogenic association; more extended studies could verify them as potential therapeutic targets.
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Affiliation(s)
- Hui Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Xiongze Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Nanying Liao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Yuying Ji
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Lan Mi
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Yuhong Gan
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Yongyue Su
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Feng Wen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
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Sun Y, Jin Y. An intraflagellar transport dependent negative feedback regulates the MAPKKK DLK-1 to protect cilia from degeneration. Proc Natl Acad Sci U S A 2023; 120:e2302801120. [PMID: 37722038 PMCID: PMC10523469 DOI: 10.1073/pnas.2302801120] [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: 02/20/2023] [Accepted: 08/15/2023] [Indexed: 09/20/2023] Open
Abstract
Primary cilia are specialized organelles supporting the development and function of cells and organisms. Intraflagellar transport (IFT) is essential for cilia formation, maintenance, and function. In C. elegans ciliated sensory neurons, IFT interacts with signaling molecules to generate distinct morphological and function features and also to maintain the integrity of cilia. Here, we report an IFT-dependent feedback control on the conserved MAPKKK DLK-1 in the ciliated sensory neurons. DLK proteins are widely known to act in synapse formation, axon regeneration, and degeneration, but their roles in other neuronal compartments are understudied. By forward genetic screening for altered expression of the endogenously tagged DLK-1 we identified multiple ift mutants showing increased DLK-1 accumulation in the defective sensory endings. We show that in response to acute IFT disruption, DLK-1 accumulates rapidly and reversibly. The expression levels of the transcription factor CEBP-1, known to act downstream of DLK-1 in the development and maintenance of synapses and axons, are also increased in the ciliated sensory neurons of ift mutants. Interestingly, the regulation of CEBP-1 expression shows sensory neuron-type dependency on DLK-1. Moreover, in the sensory neuron AWC, which has elaborate cilia morphology, up-regulated CEBP-1 represses DLK-1 at the transcription level, thereby dampening DLK-1 accumulation. Last, the IFT-dependent regulatory loop of DLK-1 and CEBP-1 offers neuroprotection in a cilia degeneration model. These findings uncover a surveillance mechanism in which tight control on the DLK-1 signaling protects cilia integrity in a context-specific manner.
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Affiliation(s)
- Yue Sun
- Department of Neurobiology, School of Biological Sciences, University of California San Diego, La Jolla, CA92093
| | - Yishi Jin
- Department of Neurobiology, School of Biological Sciences, University of California San Diego, La Jolla, CA92093
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He Q, Qu M, Shen T, Su J, Xu Y, Xu C, Barkat MQ, Cai J, Zhu H, Zeng LH, Wu X. Control of mitochondria-associated endoplasmic reticulum membranes by protein S-palmitoylation: Novel therapeutic targets for neurodegenerative diseases. Ageing Res Rev 2023; 87:101920. [PMID: 37004843 DOI: 10.1016/j.arr.2023.101920] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 03/30/2023] [Accepted: 03/30/2023] [Indexed: 04/03/2023]
Abstract
Mitochondria-associated endoplasmic reticulum membranes (MAMs) are dynamic coupling structures between mitochondria and the endoplasmic reticulum (ER). As a new subcellular structure, MAMs combine the two critical organelle functions. Mitochondria and the ER could regulate each other via MAMs. MAMs are involved in calcium (Ca2+) homeostasis, autophagy, ER stress, lipid metabolism, etc. Researchers have found that MAMs are closely related to metabolic syndrome and neurodegenerative diseases (NDs). The formation of MAMs and their functions depend on specific proteins. Numerous protein enrichments, such as the IP3R-Grp75-VDAC complex, constitute MAMs. The changes in these proteins govern the interaction between mitochondria and the ER; they also affect the biological functions of MAMs. S-palmitoylation is a reversible protein post-translational modification (PTM) that mainly occurs on protein cysteine residues. More and more studies have shown that the S-palmitoylation of proteins is closely related to their membrane localization. Here, we first briefly describe the composition and function of MAMs, reviewing the component and biological roles of MAMs mediated by S-palmitoylation, elaborating on S-palmitoylated proteins in Ca2+ flux, lipid rafts, and so on. We try to provide new insight into the molecular basis of MAMs-related diseases, mainly NDs. Finally, we propose potential drug compounds targeting S-palmitoylation.
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Affiliation(s)
- Qiangqiang He
- Department of Pharmacology, Zhejiang University School of Medicine, Hangzhou 310058, China; Department of Pharmacology, Hangzhou City University, Hangzhou 310015, China
| | - Meiyu Qu
- Department of Pharmacology, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Tingyu Shen
- Department of Pharmacology, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Jiakun Su
- Technology Center, China Tobacco Jiangxi Industrial Co. Ltd., Nanchang 330096, China
| | - Yana Xu
- Department of Pharmacology, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Chengyun Xu
- Department of Pharmacology, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Muhammad Qasim Barkat
- Department of Pharmacology, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Jibao Cai
- Technology Center, China Tobacco Jiangxi Industrial Co. Ltd., Nanchang 330096, China
| | - Haibin Zhu
- Department of Gynecology, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Ling-Hui Zeng
- Department of Pharmacology, Hangzhou City University, Hangzhou 310015, China.
| | - Ximei Wu
- Department of Pharmacology, Zhejiang University School of Medicine, Hangzhou 310058, China.
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Zhong Q, Xiao X, Qiu Y, Xu Z, Chen C, Chong B, Zhao X, Hai S, Li S, An Z, Dai L. Protein posttranslational modifications in health and diseases: Functions, regulatory mechanisms, and therapeutic implications. MedComm (Beijing) 2023; 4:e261. [PMID: 37143582 PMCID: PMC10152985 DOI: 10.1002/mco2.261] [Citation(s) in RCA: 27] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 03/26/2023] [Accepted: 03/27/2023] [Indexed: 05/06/2023] Open
Abstract
Protein posttranslational modifications (PTMs) refer to the breaking or generation of covalent bonds on the backbones or amino acid side chains of proteins and expand the diversity of proteins, which provides the basis for the emergence of organismal complexity. To date, more than 650 types of protein modifications, such as the most well-known phosphorylation, ubiquitination, glycosylation, methylation, SUMOylation, short-chain and long-chain acylation modifications, redox modifications, and irreversible modifications, have been described, and the inventory is still increasing. By changing the protein conformation, localization, activity, stability, charges, and interactions with other biomolecules, PTMs ultimately alter the phenotypes and biological processes of cells. The homeostasis of protein modifications is important to human health. Abnormal PTMs may cause changes in protein properties and loss of protein functions, which are closely related to the occurrence and development of various diseases. In this review, we systematically introduce the characteristics, regulatory mechanisms, and functions of various PTMs in health and diseases. In addition, the therapeutic prospects in various diseases by targeting PTMs and associated regulatory enzymes are also summarized. This work will deepen the understanding of protein modifications in health and diseases and promote the discovery of diagnostic and prognostic markers and drug targets for diseases.
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Affiliation(s)
- Qian Zhong
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
| | - Xina Xiao
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
| | - Yijie Qiu
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
| | - Zhiqiang Xu
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
| | - Chunyu Chen
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
| | - Baochen Chong
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
| | - Xinjun Zhao
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
| | - Shan Hai
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
| | - Shuangqing Li
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
| | - Zhenmei An
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
| | - Lunzhi Dai
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
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11
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Ramzan F, Abrar F, Mishra GG, Liao LMQ, Martin DDO. Lost in traffic: consequences of altered palmitoylation in neurodegeneration. Front Physiol 2023; 14:1166125. [PMID: 37324388 PMCID: PMC10268010 DOI: 10.3389/fphys.2023.1166125] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 05/12/2023] [Indexed: 06/17/2023] Open
Abstract
One of the first molecular events in neurodegenerative diseases, regardless of etiology, is protein mislocalization. Protein mislocalization in neurons is often linked to proteostasis deficiencies leading to the build-up of misfolded proteins and/or organelles that contributes to cellular toxicity and cell death. By understanding how proteins mislocalize in neurons, we can develop novel therapeutics that target the earliest stages of neurodegeneration. A critical mechanism regulating protein localization and proteostasis in neurons is the protein-lipid modification S-acylation, the reversible addition of fatty acids to cysteine residues. S-acylation is more commonly referred to as S-palmitoylation or simply palmitoylation, which is the addition of the 16-carbon fatty acid palmitate to proteins. Like phosphorylation, palmitoylation is highly dynamic and tightly regulated by writers (i.e., palmitoyl acyltransferases) and erasers (i.e., depalmitoylating enzymes). The hydrophobic fatty acid anchors proteins to membranes; thus, the reversibility allows proteins to be re-directed to and from membranes based on local signaling factors. This is particularly important in the nervous system, where axons (output projections) can be meters long. Any disturbance in protein trafficking can have dire consequences. Indeed, many proteins involved in neurodegenerative diseases are palmitoylated, and many more have been identified in palmitoyl-proteomic studies. It follows that palmitoyl acyl transferase enzymes have also been implicated in numerous diseases. In addition, palmitoylation can work in concert with cellular mechanisms, like autophagy, to affect cell health and protein modifications, such as acetylation, nitrosylation, and ubiquitination, to affect protein function and turnover. Limited studies have further revealed a sexually dimorphic pattern of protein palmitoylation. Therefore, palmitoylation can have wide-reaching consequences in neurodegenerative diseases.
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12
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Starr CR, Gorbatyuk MS. Posttranslational modifications of proteins in diseased retina. Front Cell Neurosci 2023; 17:1150220. [PMID: 37066080 PMCID: PMC10097899 DOI: 10.3389/fncel.2023.1150220] [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: 01/23/2023] [Accepted: 03/13/2023] [Indexed: 04/03/2023] Open
Abstract
Posttranslational modifications (PTMs) are known to constitute a key step in protein biosynthesis and in the regulation of protein functions. Recent breakthroughs in protein purification strategies and current proteome technologies make it possible to identify the proteomics of healthy and diseased retinas. Despite these advantages, the research field identifying sets of posttranslationally modified proteins (PTMomes) related to diseased retinas is significantly lagging, despite knowledge of the major retina PTMome being critical to drug development. In this review, we highlight current updates regarding the PTMomes in three retinal degenerative diseases-namely, diabetic retinopathy (DR), glaucoma, and retinitis pigmentosa (RP). A literature search reveals the necessity to expedite investigations into essential PTMomes in the diseased retina and validate their physiological roles. This knowledge would accelerate the development of treatments for retinal degenerative disorders and the prevention of blindness in affected populations.
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Affiliation(s)
| | - Marina S. Gorbatyuk
- Department of Optometry and Vision Science, University of Alabama at Birmingham, Birmingham, AL, United States
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13
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Gupta JP, Jenkins PM. Ankyrin-B is lipid-modified by S-palmitoylation to promote dendritic membrane scaffolding of voltage-gated sodium channel Na V1.2 in neurons. Front Physiol 2023; 14:959660. [PMID: 37064897 PMCID: PMC10098127 DOI: 10.3389/fphys.2023.959660] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 03/21/2023] [Indexed: 04/01/2023] Open
Abstract
Neuronal ankyrin-B is an intracellular scaffolding protein that plays multiple roles in the axon. By contrast, relatively little is known about the function of ankyrin-B in dendrites, where ankyrin-B is also localized in mature neurons. Recently, we showed that ankyrin-B acts as a scaffold for the voltage-gated sodium channel, NaV1.2, in dendrites of neocortical pyramidal neurons. How ankyrin-B is itself targeted to the dendritic membrane is not well understood. Here, we report that ankyrin-B is lipid-modified by S-palmitoylation to promote dendritic localization of NaV1.2. We identify the palmitoyl acyl transferase zDHHC17 as a key mediator of ankyrin-B palmitoylation in heterologous cells and in neurons. Additionally, we find that zDHHC17 regulates ankyrin-B protein levels independently of its S-acylation function through a conserved binding mechanism between the ANK repeat domain of zDHHC17 and the zDHHC ankyrin-repeat binding motif of ankyrin-B. We subsequently identify five cysteines in the N-terminal ankyrin repeat domain of ankyrin-B that are necessary for ankyrin-B palmitoylation. Mutation of these five cysteines to alanines not only abolishes ankyrin-B palmitoylation, but also prevents ankyrin-B from scaffolding NaV1.2 at dendritic membranes of neurons due to ankyrin-B's inability to localize properly at dendrites. Thus, we show palmitoylation is critical for localization and function of ankyrin-B at dendrites. Strikingly, loss of ankyrin-B palmitoylation does not affect ankyrin-B-mediated axonal cargo transport of synaptic vesicle synaptotagmin-1 in neurons. This is the first demonstration of S-palmitoylation of ankyrin-B as an underlying mechanism required for ankyrin-B localization and function in scaffolding NaV1.2 at dendrites.
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Affiliation(s)
- Julie P. Gupta
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI, United States
| | - Paul M. Jenkins
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI, United States
- Department of Psychiatry, University of Michigan Medical School, Ann Arbor, MI, United States
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14
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Niu J, Holland SM, Ketschek A, Collura KM, Hesketh NL, Hayashi T, Gallo G, Thomas GM. Palmitoylation couples the kinases DLK and JNK3 to facilitate prodegenerative axon-to-soma signaling. Sci Signal 2022; 15:eabh2674. [PMID: 35349303 DOI: 10.1126/scisignal.abh2674] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Dual leucine-zipper kinase (DLK; a MAP3K) mediates neuronal responses to diverse injuries and insults through the c-Jun N-terminal kinase (JNK) family of mitogen-activated protein kinases (MAPKs). Here, we identified two ways through which DLK is coupled to the neural-specific isoform JNK3 to control prodegenerative signaling. JNK3 catalyzed positive feedback phosphorylation of DLK that further activated DLK and locked the DLK-JNK3 module in a highly active state. Neither homologous MAP3Ks nor a homologous MAPK could support this positive feedback loop. Unlike the related JNK1 isoform JNK2 and JNK3 promote prodegenerative axon-to-soma signaling and were endogenously palmitoylated. Moreover, palmitoylation targeted both DLK and JNK3 to the same axonal vesicles, and JNK3 palmitoylation was essential for axonal retrograde signaling in response to optic nerve crush injury in vivo. These findings provide previously unappreciated insights into DLK-JNK signaling relevant to neuropathological conditions and answer long-standing questions regarding the selective prodegenerative roles of JNK2 and JNK3.
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Affiliation(s)
- Jingwen Niu
- Shriners Hospitals Pediatric Research Center (Center for Neurorehabilitation and Neural Repair), Lewis Katz School of Medicine at Temple University, 3500 N. Broad Street, Philadelphia, PA 19140, USA
| | - Sabrina M Holland
- Shriners Hospitals Pediatric Research Center (Center for Neurorehabilitation and Neural Repair), Lewis Katz School of Medicine at Temple University, 3500 N. Broad Street, Philadelphia, PA 19140, USA
| | - Andrea Ketschek
- Shriners Hospitals Pediatric Research Center (Center for Neurorehabilitation and Neural Repair), Lewis Katz School of Medicine at Temple University, 3500 N. Broad Street, Philadelphia, PA 19140, USA
| | - Kaitlin M Collura
- Shriners Hospitals Pediatric Research Center (Center for Neurorehabilitation and Neural Repair), Lewis Katz School of Medicine at Temple University, 3500 N. Broad Street, Philadelphia, PA 19140, USA
| | - Natasha L Hesketh
- Shriners Hospitals Pediatric Research Center (Center for Neurorehabilitation and Neural Repair), Lewis Katz School of Medicine at Temple University, 3500 N. Broad Street, Philadelphia, PA 19140, USA
| | - Takashi Hayashi
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central6 (6-10), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan
| | - Gianluca Gallo
- Shriners Hospitals Pediatric Research Center (Center for Neurorehabilitation and Neural Repair), Lewis Katz School of Medicine at Temple University, 3500 N. Broad Street, Philadelphia, PA 19140, USA.,Department of Neural Sciences, Lewis Katz School of Medicine at Temple University, 3500 N. Broad St., Philadelphia, PA 19140, USA
| | - Gareth M Thomas
- Shriners Hospitals Pediatric Research Center (Center for Neurorehabilitation and Neural Repair), Lewis Katz School of Medicine at Temple University, 3500 N. Broad Street, Philadelphia, PA 19140, USA.,Department of Neural Sciences, Lewis Katz School of Medicine at Temple University, 3500 N. Broad St., Philadelphia, PA 19140, USA
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15
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Lee B, Oh Y, Cho E, DiAntonio A, Cavalli V, Shin JE, Choi HW, Cho Y. FK506-binding protein-like and FK506-binding protein 8 regulate dual leucine zipper kinase degradation and neuronal responses to axon injury. J Biol Chem 2022; 298:101647. [PMID: 35101451 PMCID: PMC8881485 DOI: 10.1016/j.jbc.2022.101647] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 01/21/2022] [Accepted: 01/23/2022] [Indexed: 12/17/2022] Open
Abstract
The dual leucine zipper kinase (DLK) is a key regulator of axon regeneration and degeneration in response to neuronal injury; however, regulatory mechanisms of the DLK function via its interacting proteins are largely unknown. To better understand the molecular mechanism of DLK function, we performed yeast two-hybrid screening analysis and identified FK506-binding protein-like (FKBPL, also known as WAF-1/CIP1 stabilizing protein 39) as a DLK-binding protein. FKBPL binds to the kinase domain of DLK and inhibits its kinase activity. In addition, FKBPL induces DLK protein degradation through ubiquitin-dependent pathways. We further assessed other members in the FKBP protein family and found that FK506-binding protein 8 (FKBP8) also induced DLK degradation. We identified the lysine 271 residue in the kinase domain as a major site of DLK ubiquitination and SUMO3 conjugation and was thus responsible for regulating FKBP8-mediated proteasomal degradation that was inhibited by the substitution of the lysine 271 to arginine. FKBP8-mediated degradation of DLK is mediated by autophagy pathway because knockdown of Atg5 inhibited DLK destabilization. We show that in vivo overexpression of FKBP8 delayed the progression of axon degeneration and suppressed neuronal death after axotomy in sciatic and optic nerves. Taken together, this study identified FKBPL and FKBP8 as novel DLK-interacting proteins that regulate DLK stability via the ubiquitin-proteasome and lysosomal protein degradation pathways.
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Affiliation(s)
- Bohm Lee
- Department of Life Sciences, Korea University, Seoul, Republic of Korea
| | - Yeonsoo Oh
- Department of Life Sciences, Korea University, Seoul, Republic of Korea
| | - Eunhye Cho
- Department of Life Sciences, Korea University, Seoul, Republic of Korea
| | - Aaron DiAntonio
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, USA; Needleman Center for Neurometabolism and Axonal Therapeutics, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Valeria Cavalli
- Department of Neuroscience, Washington University School of Medicine, St. Louis, Missouri, USA; Center of Regenerative Medicine, Washington University School of Medicine, St. Louis, Missouri, USA; Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Jung Eun Shin
- Department of Molecular Neuroscience, Dong-A University College of Medicine, Busan, Republic of Korea; Department of Translational Biomedical Sciences, Graduate School of Dong-A University, Busan, Republic of Korea
| | - Hae Woong Choi
- Department of Life Sciences, Korea University, Seoul, Republic of Korea.
| | - Yongcheol Cho
- Department of Life Sciences, Korea University, Seoul, Republic of Korea.
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16
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Petropavlovskiy A, Kogut J, Leekha A, Townsend C, Sanders S. A sticky situation: regulation and function of protein palmitoylation with a spotlight on the axon and axon initial segment. Neuronal Signal 2021; 5:NS20210005. [PMID: 34659801 PMCID: PMC8495546 DOI: 10.1042/ns20210005] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 09/19/2021] [Accepted: 09/21/2021] [Indexed: 11/17/2022] Open
Abstract
In neurons, the axon and axon initial segment (AIS) are critical structures for action potential initiation and propagation. Their formation and function rely on tight compartmentalisation, a process where specific proteins are trafficked to and retained at distinct subcellular locations. One mechanism which regulates protein trafficking and association with lipid membranes is the modification of protein cysteine residues with the 16-carbon palmitic acid, known as S-acylation or palmitoylation. Palmitoylation, akin to phosphorylation, is reversible, with palmitate cycling being mediated by substrate-specific enzymes. Palmitoylation is well-known to be highly prevalent among neuronal proteins and is well studied in the context of the synapse. Comparatively, how palmitoylation regulates trafficking and clustering of axonal and AIS proteins remains less understood. This review provides an overview of the current understanding of the biochemical regulation of palmitoylation, its involvement in various neurological diseases, and the most up-to-date perspective on axonal palmitoylation. Through a palmitoylation analysis of the AIS proteome, we also report that an overwhelming proportion of AIS proteins are likely palmitoylated. Overall, our review and analysis confirm a central role for palmitoylation in the formation and function of the axon and AIS and provide a resource for further exploration of palmitoylation-dependent protein targeting to and function at the AIS.
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Affiliation(s)
- Andrey A. Petropavlovskiy
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Rd E, Guelph N1G 2W1, Ontario, Canada
| | - Jordan A. Kogut
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Rd E, Guelph N1G 2W1, Ontario, Canada
| | - Arshia Leekha
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Rd E, Guelph N1G 2W1, Ontario, Canada
| | - Charlotte A. Townsend
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Rd E, Guelph N1G 2W1, Ontario, Canada
| | - Shaun S. Sanders
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Rd E, Guelph N1G 2W1, Ontario, Canada
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