1
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Yeh JY, Chao HC, Hong CL, Hung YC, Tzou FY, Hsiao CT, Li JL, Chen WJ, Chou CT, Tsai YS, Liao YC, Lin YC, Lin S, Huang SY, Kennerson M, Lee YC, Chan CC. A missense mutation in human INSC causes peripheral neuropathy. EMBO Mol Med 2024; 16:1091-1114. [PMID: 38589651 PMCID: PMC11099080 DOI: 10.1038/s44321-024-00062-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 03/08/2024] [Accepted: 03/15/2024] [Indexed: 04/10/2024] Open
Abstract
PAR3/INSC/LGN form an evolutionarily conserved complex required for asymmetric cell division in the developing brain, but its post-developmental function and disease relevance in the peripheral nervous system (PNS) remains unknown. We mapped a new locus for axonal Charcot-Marie-Tooth disease (CMT2) and identified a missense mutation c.209 T > G (p.Met70Arg) in the INSC gene. Modeling the INSCM70R variant in Drosophila, we showed that it caused proprioceptive defects in adult flies, leading to gait defects resembling those in CMT2 patients. Cellularly, PAR3/INSC/LGN dysfunction caused tubulin aggregation and necrotic neurodegeneration, with microtubule-stabilizing agents rescuing both morphological and functional defects of the INSCM70R mutation in the PNS. Our findings underscore the critical role of the PAR3/INSC/LGN machinery in the adult PNS and highlight a potential therapeutic target for INSC-associated CMT2.
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Affiliation(s)
- Jui-Yu Yeh
- Graduate Institute of Physiology, National Taiwan University, Taipei, Taiwan
| | - Hua-Chuan Chao
- Department of Neurology, National Yang Ming Chiao Tung University School of Medicine, Taipei, Taiwan
- Institute of Clinical Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
- Division of Neurology, Department of Medicine, Taoyuan General Hospital, Ministry of Health and Welfare, Taoyuan, Taiwan
| | - Cheng-Li Hong
- Graduate Institute of Physiology, National Taiwan University, Taipei, Taiwan
| | - Yu-Chien Hung
- Graduate Institute of Physiology, National Taiwan University, Taipei, Taiwan
| | - Fei-Yang Tzou
- Graduate Institute of Physiology, National Taiwan University, Taipei, Taiwan
| | - Cheng-Tsung Hsiao
- Department of Neurology, National Yang Ming Chiao Tung University School of Medicine, Taipei, Taiwan
- Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Jeng-Lin Li
- Ph.D. Program in Translational Medicine, National Taiwan University and Academia Sinica, Taipei, Taiwan
- Department of Neurology, National Taiwan University Hospital Jinshan Branch, New Taipei City, Taiwan
| | - Wen-Jie Chen
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
- Taiwan International Graduate Program in Interdisciplinary Neuroscience, National Cheng Kung University and Academia Sinica, Tapiei, Taiwan
| | - Cheng-Ta Chou
- Department of Neurology, Neurological Institute, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Yu-Shuen Tsai
- Cancer and Immunology Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Yi-Chu Liao
- Department of Neurology, National Yang Ming Chiao Tung University School of Medicine, Taipei, Taiwan
- Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan
- Brain Research Center, National Yang Ming Chiao Tung University School of Medicine, Taipei, Taiwan
| | - Yu-Chun Lin
- Institute of Molecular Medicine, National Tsing Hua University, HsinChu, Taiwan
- Department of Medical Science, National Tsing Hua University, HsinChu, Taiwan
| | - Suewei Lin
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Shu-Yi Huang
- Department of Medical Research, National Taiwan University Hospital, Taipei, Taiwan
| | - Marina Kennerson
- Northcott Neuroscience Laboratory, ANZAC Research Institute, Sydney Local Health District, Concord, NSW, Australia
- School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia
- Molecular Medicine Laboratory, Concord Hospital, Concord, NSW, Australia
| | - Yi-Chung Lee
- Department of Neurology, National Yang Ming Chiao Tung University School of Medicine, Taipei, Taiwan.
- Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan.
- Brain Research Center, National Yang Ming Chiao Tung University School of Medicine, Taipei, Taiwan.
| | - Chih-Chiang Chan
- Graduate Institute of Physiology, National Taiwan University, Taipei, Taiwan.
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2
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Iuzzolino A, Pellegrini FR, Rotili D, Degrassi F, Trisciuoglio D. The α-tubulin acetyltransferase ATAT1: structure, cellular functions, and its emerging role in human diseases. Cell Mol Life Sci 2024; 81:193. [PMID: 38652325 PMCID: PMC11039541 DOI: 10.1007/s00018-024-05227-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Revised: 03/29/2024] [Accepted: 04/03/2024] [Indexed: 04/25/2024]
Abstract
The acetylation of α-tubulin on lysine 40 is a well-studied post-translational modification which has been associated with the presence of long-lived stable microtubules that are more resistant to mechanical breakdown. The discovery of α-tubulin acetyltransferase 1 (ATAT1), the enzyme responsible for lysine 40 acetylation on α-tubulin in a wide range of species, including protists, nematodes, and mammals, dates to about a decade ago. However, the role of ATAT1 in different cellular activities and molecular pathways has been only recently disclosed. This review comprehensively summarizes the most recent knowledge on ATAT1 structure and substrate binding and analyses the involvement of ATAT1 in a variety of cellular processes such as cell motility, mitosis, cytoskeletal organization, and intracellular trafficking. Finally, the review highlights ATAT1 emerging roles in human diseases and discusses ATAT1 potential enzymatic and non-enzymatic roles and the current efforts in developing ATAT1 inhibitors.
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Affiliation(s)
- Angela Iuzzolino
- IBPM Institute of Molecular Biology and Pathology, CNR National Research Council of Italy, Via degli Apuli 4, Rome, 00185, Italy
| | - Francesca Romana Pellegrini
- IBPM Institute of Molecular Biology and Pathology, CNR National Research Council of Italy, Via degli Apuli 4, Rome, 00185, Italy
| | - Dante Rotili
- Department of Drug Chemistry & Technologies, Sapienza University of Rome, Piazzale Aldo Moro 5, Rome, 00185, Italy
| | - Francesca Degrassi
- IBPM Institute of Molecular Biology and Pathology, CNR National Research Council of Italy, Via degli Apuli 4, Rome, 00185, Italy.
| | - Daniela Trisciuoglio
- IBPM Institute of Molecular Biology and Pathology, CNR National Research Council of Italy, Via degli Apuli 4, Rome, 00185, Italy.
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3
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Atkins D, Rosas JM, Månsson LK, Shahverdi N, Dey SS, Pitenis AA. Survival-Associated Cellular Response Maintained in Pancreatic Ductal Adenocarcinoma (PDAC) Switched Between Soft and Stiff 3D Microgel Culture. ACS Biomater Sci Eng 2024; 10:2177-2187. [PMID: 38466617 PMCID: PMC11005012 DOI: 10.1021/acsbiomaterials.3c01079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 02/26/2024] [Accepted: 02/26/2024] [Indexed: 03/13/2024]
Abstract
Pancreatic ductal adenocarcinoma (PDAC) accounts for about 90% of all pancreatic cancer cases. Five-year survival rates have remained below 12% since the 1970s, in part due to the difficulty in detection prior to metastasis (migration and invasion into neighboring organs and glands). Mechanical memory is a concept that has emerged over the past decade that may provide a path toward understanding how invading PDAC cells "remember" the mechanical properties of their diseased ("stiff", elastic modulus, E ≈ 10 kPa) microenvironment even while invading a healthy ("soft", E ≈ 1 kPa) microenvironment. Here, we investigated the role of mechanical priming by culturing a dilute suspension of PDAC (FG) cells within a 3D, rheologically tunable microgel platform from hydrogels with tunable mechanical properties. We conducted a suite of acute (short-term) priming studies where we cultured PDAC cells in either a soft (E ≈ 1 kPa) or stiff (E ≈ 10 kPa) environment for 6 h, then removed and placed them into a new soft or stiff 3D environment for another 18 h. Following these steps, we conducted RNA-seq analyses to quantify gene expression. Initial priming in the 3D culture showed persistent gene expression for the duration of the study, regardless of the subsequent environments (stiff or soft). Stiff 3D culture was associated with the downregulation of tumor suppressors (LATS1, BCAR3, CDKN2C), as well as the upregulation of cancer-associated genes (RAC3). Immunofluorescence staining (BCAR3, RAC3) further supported the persistence of this cellular response, with BCAR3 upregulated in soft culture and RAC3 upregulated in stiff-primed culture. Stiff-primed genes were stratified against patient data found in The Cancer Genome Atlas (TCGA). Upregulated genes in stiff-primed 3D culture were associated with decreased survival in patient data, suggesting a link between patient survival and mechanical priming.
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Affiliation(s)
- Dixon
J. Atkins
- Department
of Biomolecular Science and Engineering, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Jonah M. Rosas
- Department
of Biomolecular Science and Engineering, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Lisa K. Månsson
- Materials
Department, University of California Santa
Barbara, Santa
Barbara, California 93106, United States
| | - Nima Shahverdi
- Molecular,
Cellular, and Developmental Biology Department, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Siddharth S. Dey
- Department
of Chemical Engineering, University
of California Santa Barbara, Santa
Barbara, California 93106, United States
- Department
of Bioengineering, University of California
Santa Barbara, Santa Barbara, California 93106, United States
| | - Angela A. Pitenis
- Materials
Department, University of California Santa
Barbara, Santa
Barbara, California 93106, United States
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4
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Falconieri A, Folino P, Da Palmata L, Raffa V. Nano-pulling stimulates axon regeneration in dorsal root ganglia by inducing stabilization of axonal microtubules and activation of local translation. Front Mol Neurosci 2024; 17:1340958. [PMID: 38633213 PMCID: PMC11022966 DOI: 10.3389/fnmol.2024.1340958] [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: 11/19/2023] [Accepted: 03/11/2024] [Indexed: 04/19/2024] Open
Abstract
Introduction Axonal plasticity is strongly related to neuronal development as well as regeneration. It was recently demonstrated that active mechanical tension, intended as an extrinsic factor, is a valid contribution to the modulation of axonal plasticity. Methods In previous publications, our team validated a the "nano-pulling" method used to apply mechanical forces to developing axons of isolated primary neurons using magnetic nanoparticles (MNP) actuated by static magnetic fields. This method was found to promote axon growth and synaptic maturation. Here, we explore the use of nano-pulling as an extrinsic factor to promote axon regeneration in a neuronal tissue explant. Results Whole dorsal root ganglia (DRG) were thus dissected from a mouse spinal cord, incubated with MNPs, and then stretched. We found that particles were able to penetrate the ganglion and thus become localised both in the somas and in sprouting axons. Our results highlight that nano-pulling doubles the regeneration rate, and this is accompanied by an increase in the arborizing capacity of axons, an accumulation of cellular organelles related to mass addition (endoplasmic reticulum and mitochondria) and pre-synaptic proteins with respect to spontaneous regeneration. In line with the previous results on isolated hippocampal neurons, we observed that this process is coupled to an increase in the density of stable microtubules and activation of local translation. Discussion Our data demonstrate that nano-pulling enhances axon regeneration in whole spinal ganglia exposed to MNPs and external magnetic fields. These preliminary data represent an encouraging starting point for proposing nano-pulling as a biophysical tool for the design of novel therapies based on the use of force as an extrinsic factor for promoting nerve regeneration.
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Falconieri A, Coppini A, Raffa V. Microtubules as a signal hub for axon growth in response to mechanical force. Biol Chem 2024; 405:67-77. [PMID: 37674311 DOI: 10.1515/hsz-2023-0173] [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: 04/04/2023] [Accepted: 08/12/2023] [Indexed: 09/08/2023]
Abstract
Microtubules are highly polar structures and are characterized by high anisotropy and stiffness. In neurons, they play a key role in the directional transport of vesicles and organelles. In the neuronal projections called axons, they form parallel bundles, mostly oriented with the plus-end towards the axonal termination. Their physico-chemical properties have recently attracted attention as a potential candidate in sensing, processing and transducing physical signals generated by mechanical forces. Here, we discuss the main evidence supporting the role of microtubules as a signal hub for axon growth in response to a traction force. Applying a tension to the axon appears to stabilize the microtubules, which, in turn, coordinate a modulation of axonal transport, local translation and their cross-talk. We speculate on the possible mechanisms modulating microtubule dynamics under tension, based on evidence collected in neuronal and non-neuronal cell types. However, the fundamental question of the causal relationship between these mechanisms is still elusive because the mechano-sensitive element in this chain has not yet been identified.
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Affiliation(s)
| | - Allegra Coppini
- Department of Biology, Università di Pisa, Pisa, 56127, Italy
| | - Vittoria Raffa
- Department of Biology, Università di Pisa, Pisa, 56127, Italy
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Carmona B, Marinho HS, Matos CL, Nolasco S, Soares H. Tubulin Post-Translational Modifications: The Elusive Roles of Acetylation. BIOLOGY 2023; 12:biology12040561. [PMID: 37106761 PMCID: PMC10136095 DOI: 10.3390/biology12040561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 03/27/2023] [Accepted: 04/03/2023] [Indexed: 04/29/2023]
Abstract
Microtubules (MTs), dynamic polymers of α/β-tubulin heterodimers found in all eukaryotes, are involved in cytoplasm spatial organization, intracellular transport, cell polarity, migration and division, and in cilia biology. MTs functional diversity depends on the differential expression of distinct tubulin isotypes and is amplified by a vast number of different post-translational modifications (PTMs). The addition/removal of PTMs to α- or β-tubulins is catalyzed by specific enzymes and allows combinatory patterns largely enriching the distinct biochemical and biophysical properties of MTs, creating a code read by distinct proteins, including microtubule-associated proteins (MAPs), which allow cellular responses. This review is focused on tubulin-acetylation, whose cellular roles continue to generate debate. We travel through the experimental data pointing to α-tubulin Lys40 acetylation role as being a MT stabilizer and a typical PTM of long lived MTs, to the most recent data, suggesting that Lys40 acetylation enhances MT flexibility and alters the mechanical properties of MTs, preventing MTs from mechanical aging characterized by structural damage. Additionally, we discuss the regulation of tubulin acetyltransferases/desacetylases and their impacts on cell physiology. Finally, we analyze how changes in MT acetylation levels have been found to be a general response to stress and how they are associated with several human pathologies.
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Affiliation(s)
- Bruno Carmona
- Centro de Química Estrutural, Institute of Molecular Sciences, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
- Escola Superior de Tecnologia da Saúde de Lisboa, Instituto Politécnico de Lisboa, Av. D. João II, Lote 4.69.01, 1990-096 Lisboa, Portugal
| | - H Susana Marinho
- Centro de Química Estrutural, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Catarina Lopes Matos
- Centro de Química Estrutural, Institute of Molecular Sciences, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Sofia Nolasco
- Escola Superior de Tecnologia da Saúde de Lisboa, Instituto Politécnico de Lisboa, Av. D. João II, Lote 4.69.01, 1990-096 Lisboa, Portugal
- CIISA-Centro de Investigação Interdisciplinar em Sanidade Animal, Faculdade de Medicina Veterinária, Universidade de Lisboa, Avenida da Universidade Técnica, 1300-477 Lisboa, Portugal
| | - Helena Soares
- Centro de Química Estrutural, Institute of Molecular Sciences, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
- Escola Superior de Tecnologia da Saúde de Lisboa, Instituto Politécnico de Lisboa, Av. D. João II, Lote 4.69.01, 1990-096 Lisboa, Portugal
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7
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Niu X, Mao CX, Wang S, Wang X, Zhang Y, Hu J, Bi R, Liu Z, Shan J. α-Tubulin acetylation at lysine 40 regulates dendritic arborization and larval locomotion by promoting microtubule stability in Drosophila. PLoS One 2023; 18:e0280573. [PMID: 36827311 PMCID: PMC9955671 DOI: 10.1371/journal.pone.0280573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 01/03/2023] [Indexed: 02/25/2023] Open
Abstract
Posttranslational modification of tubulin increases the dynamic complexity and functional diversity of microtubules. Acetylation of α-tubulin at Lys-40 is a highly conserved posttranslational modification that has been shown to improve the flexibility and resilience of microtubules. Here we studied the in vivo functions of α-tubulin acetylation by knocking-out Atat, the Drosophila α-tubulin acetyltransferase, and by mutating Lys-40 to Arg in α1-tubulin. We found a reduction in the dendritic arborization of larval class I dendritic arborization (da) neurons in both mutants. The dendritic developmental defects in atat mutants could be reversed by enhancing the stability of microtubules either through knocking down the microtubule severing protein Katanin 60 or through overexpressing tubulin-specific chaperone E, suggesting that α-tubulin deacetylation impairsed dendritic morphology by decreasing the stability of microtubules. Using time-lapse recordings, we found that atat and α1-tubulinK40R mutations dramatically increased the number of dendritic protrusions that were likely to be immature dendritic precursors. Finally, we showed that both Atat and α-tubulin acetylation were required in class I da neurons to control larval locomotion. These findings add novel insight into the current knowledge of the role of α-tubulin acetylation in regulating neuronal development and functions.
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Affiliation(s)
- Xiaoxiao Niu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Province Key Laboratory of Biotechnology of Chinese Traditional Medicine, National & Local Joint Engineering Research Center of High-throughput Drug Screening Technology, School of life science, Hubei University, Wuhan, China
| | - Chuan-Xi Mao
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Province Key Laboratory of Biotechnology of Chinese Traditional Medicine, National & Local Joint Engineering Research Center of High-throughput Drug Screening Technology, School of life science, Hubei University, Wuhan, China
| | - Shan Wang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Province Key Laboratory of Biotechnology of Chinese Traditional Medicine, National & Local Joint Engineering Research Center of High-throughput Drug Screening Technology, School of life science, Hubei University, Wuhan, China
| | - Xiongxiong Wang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Province Key Laboratory of Biotechnology of Chinese Traditional Medicine, National & Local Joint Engineering Research Center of High-throughput Drug Screening Technology, School of life science, Hubei University, Wuhan, China
| | - Youyu Zhang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Province Key Laboratory of Biotechnology of Chinese Traditional Medicine, National & Local Joint Engineering Research Center of High-throughput Drug Screening Technology, School of life science, Hubei University, Wuhan, China
| | - Juncheng Hu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Province Key Laboratory of Biotechnology of Chinese Traditional Medicine, National & Local Joint Engineering Research Center of High-throughput Drug Screening Technology, School of life science, Hubei University, Wuhan, China
| | - Ran Bi
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Province Key Laboratory of Biotechnology of Chinese Traditional Medicine, National & Local Joint Engineering Research Center of High-throughput Drug Screening Technology, School of life science, Hubei University, Wuhan, China
| | - Zhihua Liu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Province Key Laboratory of Biotechnology of Chinese Traditional Medicine, National & Local Joint Engineering Research Center of High-throughput Drug Screening Technology, School of life science, Hubei University, Wuhan, China
- * E-mail: (SJ); (ZL)
| | - Jin Shan
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Province Key Laboratory of Biotechnology of Chinese Traditional Medicine, National & Local Joint Engineering Research Center of High-throughput Drug Screening Technology, School of life science, Hubei University, Wuhan, China
- * E-mail: (SJ); (ZL)
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Zocchi R, Compagnucci C, Bertini E, Sferra A. Deciphering the Tubulin Language: Molecular Determinants and Readout Mechanisms of the Tubulin Code in Neurons. Int J Mol Sci 2023; 24:ijms24032781. [PMID: 36769099 PMCID: PMC9917122 DOI: 10.3390/ijms24032781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Revised: 01/17/2023] [Accepted: 01/27/2023] [Indexed: 02/04/2023] Open
Abstract
Microtubules (MTs) are dynamic components of the cell cytoskeleton involved in several cellular functions, such as structural support, migration and intracellular trafficking. Despite their high similarity, MTs have functional heterogeneity that is generated by the incorporation into the MT lattice of different tubulin gene products and by their post-translational modifications (PTMs). Such regulations, besides modulating the tubulin composition of MTs, create on their surface a "biochemical code" that is translated, through the action of protein effectors, into specific MT-based functions. This code, known as "tubulin code", plays an important role in neuronal cells, whose highly specialized morphologies and activities depend on the correct functioning of the MT cytoskeleton and on its interplay with a myriad of MT-interacting proteins. In recent years, a growing number of mutations in genes encoding for tubulins, MT-interacting proteins and enzymes that post-translationally modify MTs, which are the main players of the tubulin code, have been linked to neurodegenerative processes or abnormalities in neural migration, differentiation and connectivity. Nevertheless, the exact molecular mechanisms through which the cell writes and, downstream, MT-interacting proteins decipher the tubulin code are still largely uncharted. The purpose of this review is to describe the molecular determinants and the readout mechanisms of the tubulin code, and briefly elucidate how they coordinate MT behavior during critical neuronal events, such as neuron migration, maturation and axonal transport.
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Affiliation(s)
- Riccardo Zocchi
- Unit of Neuromuscular Disorders, Translational Pediatrics and Clinical Genetics, Bambino Gesù Children’s Hospital, IRCCS, 00146 Rome, Italy
| | - Claudia Compagnucci
- Molecular Genetics and Functional Genomics, Bambino Gesù Children’s Research Hospital, IRCCS, 00146 Rome, Italy
| | - Enrico Bertini
- Unit of Neuromuscular Disorders, Translational Pediatrics and Clinical Genetics, Bambino Gesù Children’s Hospital, IRCCS, 00146 Rome, Italy
- Correspondence: (E.B.); or (A.S.); Tel.: +39-06-6859-2104 (E.B. & A.S.)
| | - Antonella Sferra
- Unit of Neuromuscular Disorders, Translational Pediatrics and Clinical Genetics, Bambino Gesù Children’s Hospital, IRCCS, 00146 Rome, Italy
- Correspondence: (E.B.); or (A.S.); Tel.: +39-06-6859-2104 (E.B. & A.S.)
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9
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Gong J, Chen J, Gu P, Shang Y, Ruppell KT, Yang Y, Wang F, Wen Q, Xiang Y. Shear stress activates nociceptors to drive Drosophila mechanical nociception. Neuron 2022; 110:3727-3742.e8. [PMID: 36087585 DOI: 10.1016/j.neuron.2022.08.015] [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: 09/23/2021] [Revised: 06/07/2022] [Accepted: 08/11/2022] [Indexed: 12/15/2022]
Abstract
Mechanical nociception is essential for animal survival. However, the forces involved in nociceptor activation and the underlying mechanotransduction mechanisms remain elusive. Here, we address these problems by investigating nocifensive behavior in Drosophila larvae. We show that strong poking stimulates nociceptors with a mixture of forces including shear stress and stretch. Unexpectedly, nociceptors are selectively activated by shear stress, but not stretch. Both the shear stress responses of nociceptors and nocifensive behavior require transient receptor potential A1 (TrpA1), which is specifically expressed in nociceptors. We further demonstrate that expression of mammalian or Drosophila TrpA1 in heterologous cells confers responses to shear stress but not stretch. Finally, shear stress activates TrpA1 in a membrane-delimited manner, through modulation of membrane fluidity. Together, our study reveals TrpA1 as an evolutionarily conserved mechanosensitive channel specifically activated by shear stress and suggests a critical role of shear stress in activating nociceptors to drive mechanical nociception.
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Affiliation(s)
- Jiaxin Gong
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Jiazhang Chen
- Department of Physics, Worcester Polytechnic Institute, Worcester, MA 01605, USA
| | - Pengyu Gu
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Ye Shang
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01605, USA; Program in Neuroscience, Morningside Graduate School of Biomedical Sciences, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Kendra Takle Ruppell
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01605, USA; Program in Neuroscience, Morningside Graduate School of Biomedical Sciences, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Ying Yang
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Fei Wang
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01605, USA; Program in Neuroscience, Morningside Graduate School of Biomedical Sciences, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Qi Wen
- Department of Physics, Worcester Polytechnic Institute, Worcester, MA 01605, USA.
| | - Yang Xiang
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01605, USA; Program in Neuroscience, Morningside Graduate School of Biomedical Sciences, University of Massachusetts Medical School, Worcester, MA 01605, USA.
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10
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Guru A, Saravanan S, Sharma D, Narasimha M. The microtubule end-binding proteins EB1 and Patronin modulate the spatiotemporal dynamics of myosin and pattern pulsed apical constriction. Development 2022; 149:284823. [PMID: 36440630 DOI: 10.1242/dev.199759] [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: 04/28/2021] [Accepted: 10/31/2022] [Indexed: 11/29/2022]
Abstract
Apical constriction powers amnioserosa contraction during Drosophila dorsal closure. The nucleation, movement and dispersal of apicomedial actomyosin complexes generates pulsed apical constrictions during early closure. Persistent apicomedial and circumapical actomyosin complexes drive unpulsed constrictions that follow. Here, we show that the microtubule end-binding proteins EB1 and Patronin pattern constriction dynamics and contraction kinetics by coordinating the balance of actomyosin forces in the apical plane. We find that microtubule growth from moving Patronin platforms governs the spatiotemporal dynamics of apicomedial myosin through the regulation of RhoGTPase signaling by transient EB1-RhoGEF2 interactions. We uncover the dynamic reorganization of a subset of short non-centrosomally nucleated apical microtubules that surround the coalescing apicomedial myosin complex, trail behind it as it moves and disperse as the complex dissolves. We demonstrate that apical microtubule reorganization is sensitive to Patronin levels. Microtubule depolymerization compromised apical myosin enrichment and altered constriction dynamics. Together, our findings uncover the importance of reorganization of an intact apical microtubule meshwork, by moving Patronin platforms and growing microtubule ends, in enabling the spatiotemporal modulation of actomyosin contractility and, through it, apical constriction.
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Affiliation(s)
- Anwesha Guru
- Department of Biological Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai 400005, India
| | - Surat Saravanan
- Department of Biological Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai 400005, India
| | - Deepanshu Sharma
- Department of Biological Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai 400005, India
| | - Maithreyi Narasimha
- Department of Biological Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai 400005, India
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11
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Deb Roy A, Gross EG, Pillai GS, Seetharaman S, Etienne-Manneville S, Inoue T. Non-catalytic allostery in α-TAT1 by a phospho-switch drives dynamic microtubule acetylation. J Cell Biol 2022; 221:213540. [PMID: 36222836 PMCID: PMC9565784 DOI: 10.1083/jcb.202202100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 06/03/2022] [Accepted: 07/20/2022] [Indexed: 11/22/2022] Open
Abstract
Spatiotemporally dynamic microtubule acetylation underlies diverse physiological and pathological events. Despite its ubiquity, the molecular mechanisms that regulate the sole microtubule acetylating agent, α-tubulin-N-acetyltransferase-1 (α-TAT1), remain obscure. Here, we report that dynamic intracellular localization of α-TAT1 along with its catalytic activity determines efficiency of microtubule acetylation. Specifically, we newly identified a conserved signal motif in the intrinsically disordered C-terminus of α-TAT1, consisting of three competing regulatory elements-nuclear export, nuclear import, and cytosolic retention. Their balance is tuned via phosphorylation by CDK1, PKA, and CK2, and dephosphorylation by PP2A. While the unphosphorylated form binds to importins and resides both in cytosol and nucleus, the phosphorylated form binds to specific 14-3-3 adapters and accumulates in the cytosol for maximal substrate access. Unlike other molecules with a similar phospho-regulated signal motif, α-TAT1 uniquely uses the nucleus as a hideout. This allosteric spatial regulation of α-TAT1 function may help uncover a spatiotemporal code of microtubule acetylation in normal and aberrant cell behavior.
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Affiliation(s)
- Abhijit Deb Roy
- Department of Cell Biology and Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD
| | | | | | - Shailaja Seetharaman
- Cell Polarity, Migration and Cancer Unit, Institut Pasteur, UMR3691, Université Paris Cité, Centre national de la recherche scientifique, Equipe Labellisée Ligue Contre le Cancer, Paris, France
| | - Sandrine Etienne-Manneville
- Cell Polarity, Migration and Cancer Unit, Institut Pasteur, UMR3691, Université Paris Cité, Centre national de la recherche scientifique, Equipe Labellisée Ligue Contre le Cancer, Paris, France
| | - Takanari Inoue
- Department of Cell Biology and Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD
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12
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Antel M, Simao T, Bener MB, Inaba M. Drosophila CG17003/leaky (lky) is required for microtubule acetylation in early germ cells in Drosophila ovary. PLoS One 2022; 17:e0276704. [PMID: 36342916 PMCID: PMC9639842 DOI: 10.1371/journal.pone.0276704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 10/11/2022] [Indexed: 11/09/2022] Open
Abstract
Microtubule acetylation is found in populations of stable, long-lived microtubules, occurring on the conserved lysine 40 (K40) residue of α-tubulin by α-tubulin acetyltransferases (αTATs). α-tubulin K40 acetylation has been shown to stabilize microtubules via enhancing microtubule resilience against mechanical stress. Here we show that a previously uncharacterized αTAT, Drosophila CG17003/leaky (lky), is required for α-tubulin K40 acetylation in early germ cells in Drosophila ovary. We found that loss of lky resulted in a progressive egg chamber fusion phenotype accompanied with mislocalization of germline-specific Vasa protein in somatic follicle cells. The same phenotype was observed upon replacement of endogenous α-tubulin84B with non-acetylatable α-tubulin84BK40A, suggesting α-tubulin K40 acetylation is responsible for the phenotype. Chemical disturbance of microtubules by Colcemid treatment resulted in a mislocalization of Vasa in follicle cells within a short period of time (~30 min), suggesting that the observed mislocalization is likely caused by direct leakage of cellular contents between germline and follicle cells. Taken together, this study provides a new function of α-tubulin acetylation in maintaining the cellular identity possibly by preventing the leakage of tissue-specific gene products between juxtaposing distinct cell types.
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Affiliation(s)
- Matthew Antel
- Department of Cell Biology, University of Connecticut Health, Farmington, CT, United States of America
| | - Taylor Simao
- Department of Cell Biology, University of Connecticut Health, Farmington, CT, United States of America
| | - Muhammed Burak Bener
- Department of Cell Biology, University of Connecticut Health, Farmington, CT, United States of America
| | - Mayu Inaba
- Department of Cell Biology, University of Connecticut Health, Farmington, CT, United States of America
- * E-mail:
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13
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Shao X, Liu Z, Mao S, Han L. Unraveling the Mechanobiology Underlying Traumatic Brain Injury with Advanced Technologies and Biomaterials. Adv Healthc Mater 2022; 11:e2200760. [PMID: 35841392 DOI: 10.1002/adhm.202200760] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 06/27/2022] [Indexed: 01/27/2023]
Abstract
Traumatic brain injury (TBI) is a worldwide health and socioeconomic problem, associated with prolonged and complex neurological aftermaths, including a variety of functional deficits and neurodegenerative disorders. Research on the long-term effects has highlighted that TBI shall be regarded as a chronic health condition. The initiation and exacerbation of TBI involve a series of mechanical stimulations and perturbations, accompanied by mechanotransduction events within the brain tissues. Mechanobiology thus offers a unique perspective and likely promising approach to unravel the underlying molecular and biochemical mechanisms leading to neural cells dysfunction after TBI, which may contribute to the discovery of novel targets for future clinical treatment. This article investigates TBI and the subsequent brain dysfunction from a lens of neuromechanobiology. Following an introduction, the mechanobiological insights are examined into the molecular pathology of TBI, and then an overview is given of the latest research technologies to explore neuromechanobiology, with particular focus on microfluidics and biomaterials. Challenges and prospects in the current field are also discussed. Through this article, it is hoped that extensive technical innovation in biomedical devices and materials can be encouraged to advance the field of neuromechanobiology, paving potential ways for the research and rehabilitation of neurotrauma and neurological diseases.
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Affiliation(s)
- Xiaowei Shao
- Institute of Marine Science and Technology, Shandong University, Qingdao, Shandong, 266237, China.,Suzhou Research Institute, Shandong University, Suzhou, Jiangsu, 215123, China
| | - Zhongqian Liu
- Institute of Marine Science and Technology, Shandong University, Qingdao, Shandong, 266237, China
| | - Shijie Mao
- Institute of Marine Science and Technology, Shandong University, Qingdao, Shandong, 266237, China
| | - Lin Han
- Institute of Marine Science and Technology, Shandong University, Qingdao, Shandong, 266237, China
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14
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Synaptic branch stability is mediated by non-enzymatic functions of MEC-17/αTAT1 and ATAT-2. Sci Rep 2022; 12:14003. [PMID: 35977998 PMCID: PMC9385713 DOI: 10.1038/s41598-022-18333-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 08/09/2022] [Indexed: 11/08/2022] Open
Abstract
Microtubules are fundamental elements of neuronal structure and function. They are dynamic structures formed from protofilament chains of α- and β-tubulin heterodimers. Acetylation of the lysine 40 (K40) residue of α-tubulin protects microtubules from mechanical stresses by imparting structural elasticity. The enzyme responsible for this acetylation event is MEC-17/αTAT1. Despite its functional importance, however, the consequences of altered MEC-17/αTAT1 levels on neuronal structure and function are incompletely defined. Here we demonstrate that overexpression or loss of MEC-17, or of its functional paralogue ATAT-2, causes a delay in synaptic branch extension, and defective synaptogenesis in the mechanosensory neurons of Caenorhabditis elegans. Strikingly, by adulthood, the synaptic branches in these animals are lost, while the main axon shaft remains mostly intact. We show that MEC-17 and ATAT-2 regulate the stability of the synaptic branches largely independently from their acetyltransferase domains. Genetic analyses reveals novel interactions between both mec-17 and atat-2 with the focal adhesion gene zyx-1/Zyxin, which has previously been implicated in actin remodelling. Together, our results reveal new, acetylation-independent roles for MEC-17 and ATAT-2 in the development and maintenance of neuronal architecture.
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15
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Kim HS, Suh JS, Jang YK, Ahn SH, Choi GH, Yang JY, Lim GH, Jung Y, Jiang J, Sun J, Suk M, Wang Y, Kim TJ. Förster Resonance Energy Transfer-Based Single-Cell Imaging Reveals Piezo1-Induced Ca 2+ Flux Mediates Membrane Ruffling and Cell Survival. Front Cell Dev Biol 2022; 10:865056. [PMID: 35646889 PMCID: PMC9136143 DOI: 10.3389/fcell.2022.865056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 04/25/2022] [Indexed: 01/18/2023] Open
Abstract
A mechanosensitive ion channel, Piezo1 induces non-selective cation flux in response to various mechanical stresses. However, the biological interpretation and underlying mechanisms of cells resulting from Piezo1 activation remain elusive. This study elucidates Piezo1-mediated Ca2+ influx driven by channel activation and cellular behavior using novel Förster Resonance Energy Transfer (FRET)-based biosensors and single-cell imaging analysis. Results reveal that extracellular Ca2+ influx via Piezo1 requires intact caveolin, cholesterol, and cytoskeletal support. Increased cytoplasmic Ca2+ levels enhance PKA, ERK, Rac1, and ROCK activity, which have the potential to promote cancer cell survival and migration. Furthermore, we demonstrate that Piezo1-mediated Ca2+ influx upregulates membrane ruffling, a characteristic feature of cancer cell metastasis, using spatiotemporal image correlation spectroscopy. Thus, our findings provide new insights into the function of Piezo1, suggesting that Piezo1 plays a significant role in the behavior of cancer cells.
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Affiliation(s)
- Heon-Su Kim
- Department of Integrated Biological Science, Pusan National University, Pusan, South Korea,Institute of Systems Biology, Pusan National University, Pusan, South Korea
| | - Jung-Soo Suh
- Department of Integrated Biological Science, Pusan National University, Pusan, South Korea
| | - Yoon-Kwan Jang
- Department of Integrated Biological Science, Pusan National University, Pusan, South Korea
| | - Sang-Hyun Ahn
- Department of Integrated Biological Science, Pusan National University, Pusan, South Korea
| | - Gyu-Ho Choi
- Department of Integrated Biological Science, Pusan National University, Pusan, South Korea
| | - Jin-Young Yang
- Department of Integrated Biological Science, Pusan National University, Pusan, South Korea
| | - Gah-Hyun Lim
- Department of Integrated Biological Science, Pusan National University, Pusan, South Korea
| | - Youngmi Jung
- Department of Integrated Biological Science, Pusan National University, Pusan, South Korea
| | - Jie Jiang
- Department of Cell Biology, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jie Sun
- Department of Cell Biology, School of Medicine, Zhejiang University, Hangzhou, China
| | - Myungeun Suk
- Department of Mechanical Engineering, Dong-Eui University, Pusan, South Korea
| | - Yingxiao Wang
- Department of Bioengineering, Institute of Engineering in Medicine, University of California, San Diego, La Jolla, CA, United States
| | - Tae-Jin Kim
- Department of Integrated Biological Science, Pusan National University, Pusan, South Korea,Institute of Systems Biology, Pusan National University, Pusan, South Korea,Department of Biological Sciences, Pusan National University, Pusan, South Korea,*Correspondence: Tae-Jin Kim,
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16
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Chuang YC, Chen CC. Force From Filaments: The Role of the Cytoskeleton and Extracellular Matrix in the Gating of Mechanosensitive Channels. Front Cell Dev Biol 2022; 10:886048. [PMID: 35586339 PMCID: PMC9108448 DOI: 10.3389/fcell.2022.886048] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 04/19/2022] [Indexed: 01/16/2023] Open
Abstract
The senses of proprioception, touch, hearing, and blood pressure on mechanosensitive ion channels that transduce mechanical stimuli with high sensitivity and speed. This conversion process is usually called mechanotransduction. From nematode MEC-4/10 to mammalian PIEZO1/2, mechanosensitive ion channels have evolved into several protein families that use variant gating models to convert different forms of mechanical force into electrical signals. In addition to the model of channel gating by stretching from lipid bilayers, another potent model is the opening of channels by force tethering: a membrane-bound channel is elastically tethered directly or indirectly between the cytoskeleton and the extracellular molecules, and the tethering molecules convey force to change the channel structure into an activation form. In general, the mechanical stimulation forces the extracellular structure to move relative to the cytoskeleton, deforming the most compliant component in the system that serves as a gating spring. Here we review recent studies focusing on the ion channel mechanically activated by a tethering force, the mechanotransduction-involved cytoskeletal protein, and the extracellular matrix. The mechanosensitive channel PIEZO2, DEG/ENaC family proteins such as acid-sensing ion channels, and transient receptor potential family members such as NompC are discussed. State-of-the-art techniques, such as polydimethylsiloxane indentation, the pillar array, and micropipette-guided ultrasound stimulation, which are beneficial tools for exploring the tether model, are also discussed.
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Affiliation(s)
- Yu-Chia Chuang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Chih-Cheng Chen
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
- Neuroscience Program of Academia Sinica, Academia Sinica, Taipei, Taiwan
- Taiwan Mouse Clinic, BioTReC, Academia Sinica, Taipei, Taiwan
- *Correspondence: Chih-Cheng Chen,
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17
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Abstract
Microtubules are essential cytoskeletal elements found in all eukaryotic cells. The structure and composition of microtubules regulate their function, and the dynamic remodeling of the network by posttranslational modifications and microtubule-associated proteins generates diverse populations of microtubules adapted for various contexts. In the cardiomyocyte, the microtubules must accommodate the unique challenges faced by a highly contractile, rigidly structured, and long-lasting cell. Through their canonical trafficking role and positioning of mRNA, proteins, and organelles, microtubules regulate essential cardiomyocyte functions such as electrical activity, calcium handling, protein translation, and growth. In a more specialized role, posttranslationally modified microtubules form load-bearing structures that regulate myocyte mechanics and mechanotransduction. Modified microtubules proliferate in cardiovascular diseases, creating stabilized resistive elements that impede cardiomyocyte contractility and contribute to contractile dysfunction. In this review, we highlight the most exciting new concepts emerging from recent studies into canonical and noncanonical roles of cardiomyocyte microtubules.
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Affiliation(s)
- Keita Uchida
- Department of Physiology, Pennsylvania Muscle Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA;
| | - Emily A Scarborough
- Department of Physiology, Pennsylvania Muscle Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA;
| | - Benjamin L Prosser
- Department of Physiology, Pennsylvania Muscle Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA;
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18
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Saunders HAJ, Johnson-Schlitz DM, Jenkins BV, Volkert PJ, Yang SZ, Wildonger J. Acetylated α-tubulin K394 regulates microtubule stability to shape the growth of axon terminals. Curr Biol 2022; 32:614-630.e5. [PMID: 35081332 PMCID: PMC8843987 DOI: 10.1016/j.cub.2021.12.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 10/19/2021] [Accepted: 12/07/2021] [Indexed: 02/09/2023]
Abstract
Microtubules are essential to neuron shape and function. Acetylation of tubulin has the potential to directly tune the behavior and function of microtubules in cells. Although proteomic studies have identified several acetylation sites in α-tubulin, the effects of acetylation at these sites remains largely unknown. This includes the highly conserved residue lysine 394 (K394), which is located at the αβ-tubulin dimer interface. Using a fly model, we show that α-tubulin K394 is acetylated in the nervous system and is an essential residue. We found that an acetylation-blocking mutation in endogenous α-tubulin, K394R, perturbs the synaptic morphogenesis of motoneurons and reduces microtubule stability. Intriguingly, the K394R mutation has opposite effects on the growth of two functionally and morphologically distinct motoneurons, revealing neuron-type-specific responses when microtubule stability is altered. Eliminating the deacetylase HDAC6 increases K394 acetylation, and the over-expression of HDAC6 reduces microtubule stability similar to the K394R mutant. Thus, our findings implicate α-tubulin K394 and its acetylation in the regulation of microtubule stability and suggest that HDAC6 regulates K394 acetylation during synaptic morphogenesis.
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Affiliation(s)
- Harriet A. J. Saunders
- Integrated Program in Biochemistry, University of Wisconsin-Madison, 440 Henry Mall, Madison, WI, 53706, USA,Department of Biochemistry, University of Wisconsin-Madison, 440 Henry Mall, Madison, WI, 53706, USA
| | - Dena M. Johnson-Schlitz
- Department of Biochemistry, University of Wisconsin-Madison, 440 Henry Mall, Madison, WI, 53706, USA
| | - Brian V. Jenkins
- Department of Biochemistry, University of Wisconsin-Madison, 440 Henry Mall, Madison, WI, 53706, USA
| | - Peter J. Volkert
- Department of Biochemistry, University of Wisconsin-Madison, 440 Henry Mall, Madison, WI, 53706, USA,Biochemistry Scholars Program, University of Wisconsin-Madison, 440 Henry Mall, Madison, WI, 53706, USA
| | - Sihui Z. Yang
- Department of Biochemistry, University of Wisconsin-Madison, 440 Henry Mall, Madison, WI, 53706, USA,Cellular & Molecular Biology Graduate Program, University of Wisconsin-Madison, 1525 Linden Drive, Madison, WI, 53706, USA
| | - Jill Wildonger
- Department of Biochemistry, University of Wisconsin-Madison, 440 Henry Mall, Madison, WI, 53706, USA,Current address: Pediatrics Department and Biological Sciences Division, Section of Cell and Developmental Biology, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA,Lead and author for correspondence:
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19
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Cheng KC, Hwang YL, Chiang HC. The double-edged sword effect of HDAC6 in Aβ toxicities. FASEB J 2021; 36:e22072. [PMID: 34907598 DOI: 10.1096/fj.202101061r] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 10/25/2021] [Accepted: 11/12/2021] [Indexed: 11/11/2022]
Abstract
Alzheimer's disease (AD) is marked by cognitive impairment, massive cell death, and reduced life expectancy. Pathologically, accumulated beta-amyloid (Aβ) aggregates and hyperphosphorylated tau protein is the hallmark of the disease. Although changes in cellular function and protein accumulates have been demonstrated in many different AD animal models, the molecular mechanism involved in different cellular functions and the correlation and causative relation between different protein accumulations remain elusive. Our in vivo genetic studies revealed that the molecular mechanisms involved in memory loss and lifespan shortening are different and that tau plays an essential role in mediating Aβ-induced early death. We found that when the first deacetylase (DAC) domain of histone deacetylase 6 (HDAC6) activity was increased, it regulated cortactin deacetylation to reverse Aβ-induced learning and memory deficit, but with no effect on the lifespan of the Aβ flies. On the other hand, an increased amount of the second DAC domain of HDAC6 promoted tau phosphorylation to facilitate Aβ-induced lifespan shortening without affecting learning performance in the Aβ flies. Our data also confirmed decreased acetylation in two major HDAC6 downstream proteins, suggesting increased HDAC6 activity in Aβ flies. Our data established the double-edged sword effect of HDAC6 activity in Aβ-induced pathologies. Not only did we segregate memory loss and lifespan shortening in Aβ flies, but we also provided evidence to link the Aβ with tau signaling.
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Affiliation(s)
- Kuan-Chung Cheng
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Yu-Luen Hwang
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Hsueh-Cheng Chiang
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
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20
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Eira J, Magalhães J, Macedo N, Pero ME, Misgeld T, Sousa MM, Bartolini F, Liz MA. Transthyretin Promotes Axon Growth via Regulation of Microtubule Dynamics and Tubulin Acetylation. Front Cell Dev Biol 2021; 9:747699. [PMID: 34820375 PMCID: PMC8606651 DOI: 10.3389/fcell.2021.747699] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 10/13/2021] [Indexed: 11/13/2022] Open
Abstract
Transthyretin (TTR), a plasma and cerebrospinal fluid protein, increases axon growth and organelle transport in sensory neurons. While neurons extend their axons, the microtubule (MT) cytoskeleton is crucial for the segregation of functional compartments and axonal outgrowth. Herein, we investigated whether TTR promotes axon elongation by modulating MT dynamics. We found that TTR KO mice have an intrinsic increase in dynamic MTs and reduced levels of acetylated α-tubulin in peripheral axons. In addition, they failed to modulate MT dynamics in response to sciatic nerve injury, leading to decreased regenerative capacity. Importantly, restoring acetylated α-tubulin levels of TTR KO dorsal root ganglia (DRG) neurons using an HDAC6 inhibitor is sufficient to completely revert defective MT dynamics and neurite outgrowth. In summary, our results reveal a new role for TTR in the modulation of MT dynamics by regulating α-tubulin acetylation via modulation of the acetylase ATAT1, and suggest that this activity underlies TTR neuritogenic function.
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Affiliation(s)
- Jessica Eira
- ICBAS, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal.,Neurodegeneration Team, Nerve Regeneration Group, Instituto de Biologia Molecular e Celular-IBMC, and i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Joana Magalhães
- Neurodegeneration Team, Nerve Regeneration Group, Instituto de Biologia Molecular e Celular-IBMC, and i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Nídia Macedo
- Neurodegeneration Team, Nerve Regeneration Group, Instituto de Biologia Molecular e Celular-IBMC, and i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Maria Elena Pero
- Department of Pathology & Cell Biology, Columbia University, New York, NY, United States.,Department of Veterinary Medicine and Animal Production, University of Naples Federico II, Naples, Italy
| | - Thomas Misgeld
- Institute of Neuronal Cell Biology, Technical University of Munich, German Center for Neurodegenerative Diseases (DZNE), Munich Cluster of Systems Neurology (SyNergy), Munich, Germany
| | - Mónica M Sousa
- Nerve Regeneration Group, Instituto de Biologia Molecular e Celular-IBMC, and i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Francesca Bartolini
- Department of Pathology & Cell Biology, Columbia University, New York, NY, United States
| | - Márcia A Liz
- Neurodegeneration Team, Nerve Regeneration Group, Instituto de Biologia Molecular e Celular-IBMC, and i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
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21
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Lin PK, Salvador J, Xie J, Aguera KN, Koller GM, Kemp SS, Griffin CT, Davis GE. Selective and Marked Blockade of Endothelial Sprouting Behavior Using Paclitaxel and Related Pharmacologic Agents. THE AMERICAN JOURNAL OF PATHOLOGY 2021; 191:2245-2264. [PMID: 34563512 DOI: 10.1016/j.ajpath.2021.08.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 08/10/2021] [Accepted: 08/26/2021] [Indexed: 12/11/2022]
Abstract
Whether alterations in the microtubule cytoskeleton affect the ability of endothelial cells (ECs) to sprout and form branching networks of tubes was investigated in this study. Bioassays of human EC tubulogenesis, where both sprouting behavior and lumen formation can be rigorously evaluated, were used to demonstrate that addition of the microtubule-stabilizing drugs, paclitaxel, docetaxel, ixabepilone, and epothilone B, completely interferes with EC tip cells and sprouting behavior, while allowing for EC lumen formation. In bioassays mimicking vasculogenesis using single or aggregated ECs, these drugs induce ring-like lumens from single cells or cyst-like spherical lumens from multicellular aggregates with no evidence of EC sprouting behavior. Remarkably, treatment of these cultures with a low dose of the microtubule-destabilizing drug, vinblastine, led to an identical result, with complete blockade of EC sprouting, but allowing for EC lumen formation. Administration of paclitaxel in vivo markedly interfered with angiogenic sprouting behavior in developing mouse retina, providing corroboration. These findings reveal novel biological activities for pharmacologic agents that are widely utilized in multidrug chemotherapeutic regimens for the treatment of human malignant cancers. Overall, this work demonstrates that manipulation of microtubule stability selectively interferes with the ability of ECs to sprout, a necessary step to initiate and form branched capillary tube networks.
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Affiliation(s)
- Prisca K Lin
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida School of Medicine, Tampa, Florida
| | - Jocelynda Salvador
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida School of Medicine, Tampa, Florida
| | - Jun Xie
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Kalia N Aguera
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida School of Medicine, Tampa, Florida
| | - Gretchen M Koller
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida School of Medicine, Tampa, Florida
| | - Scott S Kemp
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida School of Medicine, Tampa, Florida
| | - Courtney T Griffin
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma; Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - George E Davis
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida School of Medicine, Tampa, Florida.
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22
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MacTaggart B, Kashina A. Posttranslational modifications of the cytoskeleton. Cytoskeleton (Hoboken) 2021; 78:142-173. [PMID: 34152688 DOI: 10.1002/cm.21679] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 06/13/2021] [Accepted: 06/16/2021] [Indexed: 12/12/2022]
Abstract
The cytoskeleton plays important roles in many essential processes at the cellular and organismal levels, including cell migration and motility, cell division, and the establishment and maintenance of cell and tissue architecture. In order to facilitate these varied functions, the main cytoskeletal components-microtubules, actin filaments, and intermediate filaments-must form highly diverse intracellular arrays in different subcellular areas and cell types. The question of how this diversity is conferred has been the focus of research for decades. One key mechanism is the addition of posttranslational modifications (PTMs) to the major cytoskeletal proteins. This posttranslational addition of various chemical groups dramatically increases the complexity of the cytoskeletal proteome and helps facilitate major global and local cytoskeletal functions. Cytoskeletal proteins undergo many PTMs, most of which are not well understood. Recent technological advances in proteomics and cell biology have allowed for the in-depth study of individual PTMs and their functions in the cytoskeleton. Here, we provide an overview of the major PTMs that occur on the main structural components of the three cytoskeletal systems-tubulin, actin, and intermediate filament proteins-and highlight the cellular function of these modifications.
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Affiliation(s)
- Brittany MacTaggart
- School of Veterinary Medicine, Department of Biomedical Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Anna Kashina
- School of Veterinary Medicine, Department of Biomedical Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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23
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Liu W, Xu C, Meng Q, Kang P. The clinical value of kinesin superfamily protein 2A in hepatocellular carcinoma. Clin Res Hepatol Gastroenterol 2021; 45:101527. [PMID: 33713978 DOI: 10.1016/j.clinre.2020.08.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 07/28/2020] [Accepted: 08/24/2020] [Indexed: 02/04/2023]
Abstract
BACKGROUND This study aimed to investigate the clinical value of kinesin superfamily protein 2A (KIF2A) in hepatocellular carcinoma (HCC) patients. METHODS This study retrospectively analyzed 196 HCC patients who underwent hepatic resection, and their preoperative clinical characteristics were collected from the medical records. Immunohistochemical (IHC) assay was performed to detect KIF2A expression, subsequently KIF2A expression was evaluated by a semi-quantitative IHC score (according to IHC staining density and intensity of positively stained cells) and then graded as KIF2A-/KIF2A+/KIF2A++/KIF2A+++ for analysis. Overall survival (OS) was calculated from the date of resection to the date of death. RESULTS Compared to adjacent tissue, both KIF2A IHC score and grade were higher in tumor tissue (Both P < 0.001). Tumor KIF2A expression was positively correlated with performance status score (P = 0.001), multifocal tumor nodule (P = 0.018), largest tumor size (P = 0.015) and Barcelona clinic liver cancer stage (P < 0.001). Regarding live function indexes, tumor KIF2A expression was positively associated with aspartate aminotransferase (P = 0.006). As to tumor markers, tumor KIF2A expression showed a trend to be positively correlated with alpha fetoprotein (P = 0.060) and carbohydrate antigen 199 (P = 0.053), but no statistical significance. Kaplan-Meier curve showed that tumor higher KIF2A expression was associated with worse OS (P < 0.001), which was further validated by multivariate Cox's regression analysis as higher an independent factor predicting shorter OS (P = 0.001). CONCLUSION KIF2A is upregulated in tumor tissue than adjacent tissue, importantly, tumor KIF2A is associated with worse liver function, raised tumor stage and poor OS in HCC patients.
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Affiliation(s)
- Wenjuan Liu
- Department of Infectious Diseases, The Second Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Chunlin Xu
- Department of Infectious Diseases, The Second Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Qingyang Meng
- Department of Infectious Diseases, The Second Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Peng Kang
- Department of Infectious Diseases, The Second Affiliated Hospital of Harbin Medical University, Harbin, China.
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24
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Novel function of N-acetyltransferase for microtubule stability and JNK signaling in Drosophila organ development. Proc Natl Acad Sci U S A 2021; 118:2010140118. [PMID: 33479178 DOI: 10.1073/pnas.2010140118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Regulation of microtubule stability is crucial for the maintenance of cell structure and function. While the acetylation of α-tubulin lysine 40 by acetylase has been implicated in the regulation of microtubule stability, the in vivo functions of N-terminal acetyltransferases (NATs) involved in the acetylation of N-terminal amino acids are not well known. Here, we identify an N-terminal acetyltransferase, Mnat9, that regulates cell signaling and microtubule stability in Drosophila Loss of Mnat9 causes severe developmental defects in multiple tissues. In the wing imaginal disc, Mnat9 RNAi leads to the ectopic activation of c-Jun N-terminal kinase (JNK) signaling and apoptotic cell death. These defects are suppressed by reducing the level of JNK signaling. Overexpression of Mnat9 can also inhibit JNK signaling. Mnat9 colocalizes with mitotic spindles, and its loss results in various spindle defects during mitosis in the syncytial embryo. Furthermore, overexpression of Mnat9 enhances microtubule stability. Mnat9 is physically associated with microtubules and shows a catalytic activity in acetylating N-terminal peptides of α- and β-tubulin in vitro. Cell death and tissue loss in Mnat9-depleted wing discs are restored by reducing the severing protein Spastin, suggesting that Mnat9 protects microtubules from its severing activity. Remarkably, Mnat9 mutated in the acetyl-CoA binding site is as functional as its wild-type form. We also find that human NAT9 can rescue Mnat9 RNAi phenotypes in flies, indicating their functional conservation. Taken together, we propose that Mnat9 is required for microtubule stability and regulation of JNK signaling to promote cell survival in developing Drosophila organs.
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25
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Richardson J, Kotevski A, Poole K. From stretch to deflection: the importance of context in the activation of mammalian, mechanically activated ion channels. FEBS J 2021; 289:4447-4469. [PMID: 34060230 DOI: 10.1111/febs.16041] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 05/11/2021] [Accepted: 05/28/2021] [Indexed: 01/21/2023]
Abstract
The ability of cells to convert mechanical perturbations into biochemical information is an essential aspect of mammalian physiology. The molecules that mediate such mechanotransduction include mechanically activated ion channels, which directly convert mechanical inputs into electrochemical signals. The unifying feature of these channels is that their open probability increases with the application of a mechanical input. However, the structure, activation profile and sensitivity of distinct mechanically activated ion channels vary from channel to channel. In this review, we discuss how ionic currents can be mechanically evoked and monitored in vitro, and describe the distinct activation profiles displayed by a range of mammalian channels. In addition, we discuss the various mechanisms by which the best-characterized mammalian, mechanically activated ion channel, PIEZO1, can be modulated. The diversity of activation and modulation of these mammalian ion channels suggest that these molecules may facilitate a finely controlled and diverse ability to sense mechanical inputs in mammalian cells.
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Affiliation(s)
- Jessica Richardson
- EMBL Australia node in Single Molecule Science, School of Medical Sciences, Faculty of Medicine & Health, University of New South Wales, Sydney, NSW, Australia.,Cellular and Systems Physiology, School of Medical Sciences, Faculty of Medicine & Health, University of New South Wales, Sydney, NSW, Australia
| | - Adrian Kotevski
- EMBL Australia node in Single Molecule Science, School of Medical Sciences, Faculty of Medicine & Health, University of New South Wales, Sydney, NSW, Australia.,Cellular and Systems Physiology, School of Medical Sciences, Faculty of Medicine & Health, University of New South Wales, Sydney, NSW, Australia
| | - Kate Poole
- EMBL Australia node in Single Molecule Science, School of Medical Sciences, Faculty of Medicine & Health, University of New South Wales, Sydney, NSW, Australia.,Cellular and Systems Physiology, School of Medical Sciences, Faculty of Medicine & Health, University of New South Wales, Sydney, NSW, Australia
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26
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Coleman AK, Joca HC, Shi G, Lederer WJ, Ward CW. Tubulin acetylation increases cytoskeletal stiffness to regulate mechanotransduction in striated muscle. J Gen Physiol 2021; 153:211904. [PMID: 33740038 PMCID: PMC7988512 DOI: 10.1085/jgp.202012743] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 01/29/2021] [Accepted: 03/01/2021] [Indexed: 12/16/2022] Open
Abstract
Microtubules tune cytoskeletal stiffness, which affects cytoskeletal mechanics and mechanotransduction of striated muscle. While recent evidence suggests that microtubules enriched in detyrosinated α-tubulin regulate these processes in healthy muscle and increase them in disease, the possible contribution from several other α-tubulin modifications has not been investigated. Here, we used genetic and pharmacologic strategies in isolated cardiomyocytes and skeletal myofibers to increase the level of acetylated α-tubulin without altering the level of detyrosinated α-tubulin. We show that microtubules enriched in acetylated α-tubulin increase cytoskeletal stiffness and viscoelastic resistance. These changes slow rates of contraction and relaxation during unloaded contraction and increased activation of NADPH oxidase 2 (Nox2) by mechanotransduction. Together, these findings add to growing evidence that microtubules contribute to the mechanobiology of striated muscle in health and disease.
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Affiliation(s)
- Andrew K Coleman
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD
| | - Humberto C Joca
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD
| | - Guoli Shi
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD
| | - W Jonathan Lederer
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD
| | - Christopher W Ward
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD
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27
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Abstract
Mechanosensing is a key feature through which organisms can receive inputs from the environment and convert them into specific functional and behavioral outputs. Mechanosensation occurs in many cells and tissues, regulating a plethora of molecular processes based on the distribution of forces and stresses both at the cell membrane and at the intracellular organelles levels, through complex interactions between cells’ microstructures, cytoskeleton, and extracellular matrix. Although several primary and secondary mechanisms have been shown to contribute to mechanosensation, a fundamental pathway in simple organisms and mammals involves the presence of specialized sensory neurons and the presence of different types of mechanosensitive ion channels on the neuronal cell membrane. In this contribution, we present a review of the main ion channels which have been proven to be significantly involved in mechanotransduction in neurons. Further, we discuss recent studies focused on the biological mechanisms and modeling of mechanosensitive ion channels’ gating, and on mechanotransduction modeling at different scales and levels of details.
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28
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Chang W, Gu JG. Role of microtubules in Piezo2 mechanotransduction of mouse Merkel cells. J Neurophysiol 2020; 124:1824-1831. [PMID: 33085566 DOI: 10.1152/jn.00502.2020] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Piezo2 channels are expressed in Merkel cells and somatosensory neurons to mediate mechanotransduction leading to the sense of touch. Components of the cytoskeleton including microtubules are key intracellular structures that maintain cellular membrane mechanics and thereby may be important in mechanotransduction. In the present study, we have explored, with microtubule-targeting agents, the potential role of microtubules in Piezo2-mediated mechanotransduction in Merkel cells of mouse whisker hair follicles. Applying patch-clamp recordings to Merkel cells in situ in whisker hair follicles, we show that Piezo2-mediated mechanically activated (MA) currents in Merkel cells are significantly potentiated by the microtubule stabilizer paclitaxel but reduced by the microtubule destabilizer vincristine. Furthermore, electrophysiological recordings made from whisker hair follicle afferent nerves show that mechanically evoked whisker afferent impulses are significantly enhanced by paclitaxel and its analog docetaxel but significantly suppressed by vincristine and its analog vinblastine. Our findings suggest that microtubules play an essential role in Piezo2 mechanotransduction in Merkel cells.NEW & NOTEWORTHY Piezo2 channels are expressed in Merkel cells to mediate mechanotransduction leading to the sense of touch. Here we determined the role of microtubules in regulating Piezo2-mediated mechanotransduction in Merkel cells. Piezo2-mediated currents in Merkel cells are potentiated by microtubule stabilizer paclitaxel but reduced by microtubule destabilizer vincristine. Mechanically evoked afferent impulses are also enhanced by microtubule stabilizers and suppressed by microtubule destabilizers. Microtubules may play an essential role in Piezo2 mechanotransduction in Merkel cells.
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Affiliation(s)
- Weipang Chang
- Department of Anesthesiology and Perioperative Medicine, School of Medicine, University of Alabama, Birmingham, Alabama
| | - Jianguo G Gu
- Department of Anesthesiology and Perioperative Medicine, School of Medicine, University of Alabama, Birmingham, Alabama
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29
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Javier-Torrent M, Zimmer-Bensch G, Nguyen L. Mechanical Forces Orchestrate Brain Development. Trends Neurosci 2020; 44:110-121. [PMID: 33203515 DOI: 10.1016/j.tins.2020.10.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 10/05/2020] [Accepted: 10/26/2020] [Indexed: 02/06/2023]
Abstract
During brain development, progenitors generate successive waves of neurons that populate distinct cerebral regions, where they settle and differentiate within layers or nuclei. While migrating and differentiating, neurons are subjected to mechanical forces arising from the extracellular matrix, and their interaction with neighboring cells. Changes in brain biomechanical properties, during its formation or aging, are converted in neural cells by mechanotransduction into intracellular signals that control key neurobiological processes. Here, we summarize recent findings that support the contribution of mechanobiology to neurodevelopment, with focus on the cerebral cortex. Also discussed are the existing toolbox and emerging technologies made available to assess and manipulate the physical properties of neurons and their environment.
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Affiliation(s)
- Míriam Javier-Torrent
- GIGA Stem Cells, GIGA-Neurosciences, University of Liège, CHU Sart Tilman, Liège 4000, Belgium
| | | | - Laurent Nguyen
- GIGA Stem Cells, GIGA-Neurosciences, University of Liège, CHU Sart Tilman, Liège 4000, Belgium.
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30
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Moutin MJ, Bosc C, Peris L, Andrieux A. Tubulin post-translational modifications control neuronal development and functions. Dev Neurobiol 2020; 81:253-272. [PMID: 33325152 PMCID: PMC8246997 DOI: 10.1002/dneu.22774] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 05/26/2020] [Accepted: 07/14/2020] [Indexed: 12/22/2022]
Abstract
Microtubules (MTs) are an essential component of the neuronal cytoskeleton; they are involved in various aspects of neuron development, maintenance, and functions including polarization, synaptic plasticity, and transport. Neuronal MTs are highly heterogeneous due to the presence of multiple tubulin isotypes and extensive post‐translational modifications (PTMs). These PTMs—most notably detyrosination, acetylation, and polyglutamylation—have emerged as important regulators of the neuronal microtubule cytoskeleton. With this review, we summarize what is currently known about the impact of tubulin PTMs on microtubule dynamics, neuronal differentiation, plasticity, and transport as well as on brain function in normal and pathological conditions, in particular during neuro‐degeneration. The main therapeutic approaches to neuro‐diseases based on the modulation of tubulin PTMs are also summarized. Overall, the review indicates how tubulin PTMs can generate a large number of functionally specialized microtubule sub‐networks, each of which is crucial to specific neuronal features.
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Affiliation(s)
- Marie-Jo Moutin
- Grenoble Institut Neurosciences, University Grenoble Alpes, Inserm, U1216, CEA, CNRS, Grenoble, France
| | - Christophe Bosc
- Grenoble Institut Neurosciences, University Grenoble Alpes, Inserm, U1216, CEA, CNRS, Grenoble, France
| | - Leticia Peris
- Grenoble Institut Neurosciences, University Grenoble Alpes, Inserm, U1216, CEA, CNRS, Grenoble, France
| | - Annie Andrieux
- Grenoble Institut Neurosciences, University Grenoble Alpes, Inserm, U1216, CEA, CNRS, Grenoble, France
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31
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Dobbelaere J, Schmidt Cernohorska M, Huranova M, Slade D, Dammermann A. Cep97 Is Required for Centriole Structural Integrity and Cilia Formation in Drosophila. Curr Biol 2020; 30:3045-3056.e7. [DOI: 10.1016/j.cub.2020.05.078] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 02/25/2020] [Accepted: 05/26/2020] [Indexed: 01/19/2023]
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32
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Roll-Mecak A. The Tubulin Code in Microtubule Dynamics and Information Encoding. Dev Cell 2020; 54:7-20. [PMID: 32634400 PMCID: PMC11042690 DOI: 10.1016/j.devcel.2020.06.008] [Citation(s) in RCA: 128] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 05/08/2020] [Accepted: 06/03/2020] [Indexed: 01/05/2023]
Abstract
Microtubules are non-covalent mesoscale polymers central to the eukaryotic cytoskeleton. Microtubule structure, dynamics, and mechanics are modulated by a cell's choice of tubulin isoforms and post-translational modifications, a "tubulin code," which is thought to support the diverse morphology and dynamics of microtubule arrays across various cell types, cell cycle, and developmental stages. We give a brief historical overview of research into tubulin diversity and highlight recent progress toward uncovering the mechanistic underpinnings of the tubulin code. As a large number of essential pathways converge upon the microtubule cytoskeleton, understanding how cells utilize tubulin diversity is crucial to understanding cellular physiology and disease.
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Affiliation(s)
- Antonina Roll-Mecak
- Cell Biology and Biophysics Unit, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892, USA; Biochemistry and Biophysics Center, National Heart Lung and Blood Institute, Bethesda, MD 20892, USA.
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33
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Rolls MM, Thyagarajan P, Feng C. Microtubule dynamics in healthy and injured neurons. Dev Neurobiol 2020; 81:321-332. [PMID: 32291942 DOI: 10.1002/dneu.22746] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 01/22/2020] [Accepted: 04/08/2020] [Indexed: 12/28/2022]
Abstract
Most neurons must last a lifetime and their microtubule cytoskeleton is an important contributor to their longevity. Neurons have some of the most stable microtubules of all cells, but the tip of every microtubule remains dynamic and, although requiring constant GTP consumption, microtubules are always being rebuilt. While some ongoing level of rebuilding always occurs, overall microtubule stability can be modulated in response to injury and stress as well as the normal developmental process of pruning. Specific microtubule severing proteins act in different contexts to increase microtubule dynamicity and promote degeneration and pruning. After axon injury, complex changes in dynamics occur and these are important for both neuroprotection induced by injury and subsequent outgrowth of a new axon. Understanding how microtubule dynamics is modulated in different scenarios, as well as the impact of the changes in stability, is an important avenue to explore for development of strategies to promote neuroprotection and regeneration.
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Affiliation(s)
- Melissa M Rolls
- Biochemistry and Molecular Biology and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, USA
| | - Pankajam Thyagarajan
- Biochemistry and Molecular Biology and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, USA
| | - Chengye Feng
- Biochemistry and Molecular Biology and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, USA
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34
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The tubulin code and its role in controlling microtubule properties and functions. Nat Rev Mol Cell Biol 2020; 21:307-326. [PMID: 32107477 DOI: 10.1038/s41580-020-0214-3] [Citation(s) in RCA: 379] [Impact Index Per Article: 94.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/14/2020] [Indexed: 02/07/2023]
Abstract
Microtubules are core components of the eukaryotic cytoskeleton with essential roles in cell division, shaping, motility and intracellular transport. Despite their functional heterogeneity, microtubules have a highly conserved structure made from almost identical molecular building blocks: the tubulin proteins. Alternative tubulin isotypes and a variety of post-translational modifications control the properties and functions of the microtubule cytoskeleton, a concept known as the 'tubulin code'. Here we review the current understanding of the molecular components of the tubulin code and how they impact microtubule properties and functions. We discuss how tubulin isotypes and post-translational modifications control microtubule behaviour at the molecular level and how this translates into physiological functions at the cellular and organism levels. We then go on to show how fine-tuning of microtubule function by some tubulin modifications can affect homeostasis and how perturbation of this fine-tuning can lead to a range of dysfunctions, many of which are linked to human disease.
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35
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Jin P, Jan LY, Jan YN. Mechanosensitive Ion Channels: Structural Features Relevant to Mechanotransduction Mechanisms. Annu Rev Neurosci 2020; 43:207-229. [PMID: 32084327 DOI: 10.1146/annurev-neuro-070918-050509] [Citation(s) in RCA: 116] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Activation of mechanosensitive ion channels underlies a variety of fundamental physiological processes that require sensation of mechanical force. Different mechanosensitive channels adapt distinctive structures and mechanotransduction mechanisms to fit their biological roles. How mechanosensitive channels work, especially in animals, has been extensively studied in the past decade. Here we review key findings in the functional and structural characterizations of these channels and highlight the structural features relevant to the mechanotransduction mechanism of each specific channel.
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Affiliation(s)
- Peng Jin
- Department of Physiology, University of California, San Francisco, California 94158, USA;
| | - Lily Yeh Jan
- Department of Physiology, University of California, San Francisco, California 94158, USA; .,Department of Biochemistry and Biophysics and Howard Hughes Medical Institute, University of California, San Francisco, California 94158, USA
| | - Yuh-Nung Jan
- Department of Physiology, University of California, San Francisco, California 94158, USA; .,Department of Biochemistry and Biophysics and Howard Hughes Medical Institute, University of California, San Francisco, California 94158, USA
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36
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Coombes CE, Saunders HAJ, Mannava AG, Johnson-Schlitz DM, Reid TA, Parmar S, McClellan M, Yan C, Rogers SL, Parrish JZ, Wagenbach M, Wordeman L, Wildonger J, Gardner MK. Non-enzymatic Activity of the α-Tubulin Acetyltransferase αTAT Limits Synaptic Bouton Growth in Neurons. Curr Biol 2020; 30:610-623.e5. [PMID: 31928876 DOI: 10.1016/j.cub.2019.12.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 10/16/2019] [Accepted: 12/06/2019] [Indexed: 10/25/2022]
Abstract
Neuronal axons terminate as synaptic boutons that form stable yet plastic connections with their targets. Synaptic bouton development relies on an underlying network of both long-lived and dynamic microtubules that provide structural stability for the boutons while also allowing for their growth and remodeling. However, a molecular-scale mechanism that explains how neurons appropriately balance these two microtubule populations remains a mystery. We hypothesized that α-tubulin acetyltransferase (αTAT), which both stabilizes long-lived microtubules against mechanical stress via acetylation and has been implicated in promoting microtubule dynamics, could play a role in this process. Using the Drosophila neuromuscular junction as a model, we found that non-enzymatic dαTAT activity limits the growth of synaptic boutons by affecting dynamic, but not stable, microtubules. Loss of dαTAT results in the formation of ectopic boutons. These ectopic boutons can be similarly suppressed by resupplying enzyme-inactive dαTAT or by treatment with a low concentration of the microtubule-targeting agent vinblastine, which acts to suppress microtubule dynamics. Biophysical reconstitution experiments revealed that non-enzymatic αTAT1 activity destabilizes dynamic microtubules but does not substantially impact the stability of long-lived microtubules. Further, during microtubule growth, non-enzymatic αTAT1 activity results in increasingly extended tip structures, consistent with an increased rate of acceleration of catastrophe frequency with microtubule age, perhaps via tip structure remodeling. Through these mechanisms, αTAT enriches for stable microtubules at the expense of dynamic ones. We propose that the specific suppression of dynamic microtubules by non-enzymatic αTAT activity regulates the remodeling of microtubule networks during synaptic bouton development.
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Affiliation(s)
- Courtney E Coombes
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Harriet A J Saunders
- Integrated Program in Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA; Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Anirudh G Mannava
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | | | - Taylor A Reid
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Sneha Parmar
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Mark McClellan
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Connie Yan
- Department of Biology, University of Washington, Seattle, WA 98195, USA
| | - Stephen L Rogers
- Department of Biology, Integrative Program for Biological and Genome Sciences, and Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Jay Z Parrish
- Department of Biology, University of Washington, Seattle, WA 98195, USA
| | - Michael Wagenbach
- Department of Physiology and Biophysics, The University of Washington, Seattle, WA 98195, USA
| | - Linda Wordeman
- Department of Physiology and Biophysics, The University of Washington, Seattle, WA 98195, USA
| | - Jill Wildonger
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA.
| | - Melissa K Gardner
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA.
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37
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Hahn I, Voelzmann A, Liew YT, Costa-Gomes B, Prokop A. The model of local axon homeostasis - explaining the role and regulation of microtubule bundles in axon maintenance and pathology. Neural Dev 2019; 14:11. [PMID: 31706327 PMCID: PMC6842214 DOI: 10.1186/s13064-019-0134-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 10/02/2019] [Indexed: 12/20/2022] Open
Abstract
Axons are the slender, cable-like, up to meter-long projections of neurons that electrically wire our brains and bodies. In spite of their challenging morphology, they usually need to be maintained for an organism's lifetime. This makes them key lesion sites in pathological processes of ageing, injury and neurodegeneration. The morphology and physiology of axons crucially depends on the parallel bundles of microtubules (MTs), running all along to serve as their structural backbones and highways for life-sustaining cargo transport and organelle dynamics. Understanding how these bundles are formed and then maintained will provide important explanations for axon biology and pathology. Currently, much is known about MTs and the proteins that bind and regulate them, but very little about how these factors functionally integrate to regulate axon biology. As an attempt to bridge between molecular mechanisms and their cellular relevance, we explain here the model of local axon homeostasis, based on our own experiments in Drosophila and published data primarily from vertebrates/mammals as well as C. elegans. The model proposes that (1) the physical forces imposed by motor protein-driven transport and dynamics in the confined axonal space, are a life-sustaining necessity, but pose a strong bias for MT bundles to become disorganised. (2) To counterbalance this risk, MT-binding and -regulating proteins of different classes work together to maintain and protect MT bundles as necessary transport highways. Loss of balance between these two fundamental processes can explain the development of axonopathies, in particular those linking to MT-regulating proteins, motors and transport defects. With this perspective in mind, we hope that more researchers incorporate MTs into their work, thus enhancing our chances of deciphering the complex regulatory networks that underpin axon biology and pathology.
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Affiliation(s)
- Ines Hahn
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, The University of Manchester, School of Biology, Manchester, UK
| | - André Voelzmann
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, The University of Manchester, School of Biology, Manchester, UK
| | - Yu-Ting Liew
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, The University of Manchester, School of Biology, Manchester, UK
| | - Beatriz Costa-Gomes
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, The University of Manchester, School of Biology, Manchester, UK
| | - Andreas Prokop
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, The University of Manchester, School of Biology, Manchester, UK.
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38
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Zhang Q, Lu D, Liu W, Ye S, Guo H, Liao T, Chen C. Effects of KIF2A on the prognosis of nasopharyngeal carcinoma and nasopharyngeal carcinoma cells. Oncol Lett 2019; 18:2718-2723. [PMID: 31452750 DOI: 10.3892/ol.2019.10597] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 06/13/2019] [Indexed: 02/07/2023] Open
Abstract
Nasopharyngeal carcinoma (NPC) is a common tumor in south China. Kinesin family member 2A (KIF2A) belongs to the kinesin-13 family and is associated with the growth and invasion of a number of different types of human cancer, including ovarian, breast and prostate cancer. The aim of the present study was to evaluate the expression of KIF2A in NPC and explore the relationship between KIF2A and the basic characteristics of 5-8F cells. Immunohistochemistry was performed on tissues from 97 patients with NPC to assess KIF2A protein expression. KIF2A was knocked down by a specific short interfering (si)RNA in 5-8F cell lines. Cell proliferation, apoptosis and cycle were analyzed by MTT assay and flow cytometry. The invasive ability and angiogenesis were evaluated by Matrigel assay and reverse transcription-quantitative PCR. The level of KIF2A was associated with the growth and migration of primary tumor, nodal status and tumor stage. The viability of KIF2A-knockdown cells was decreased compared with that of the control cells. The number of apoptotic cells, as well as the percentage of cells in the G0/G1 phase, was higher in the KIF2A siRNA group compared with the control group. The invasive and angiogenetic ability of 5-8F cells in the KIF2A siRNA group was decreased compared with the control group. In conclusion, the expression of KIF2A correlated with the poor clinicopathological features in NPC. Therefore, KIF2A may serve an important role in the progression of NPC and proliferation of 5-8F cells, which might present a potential therapeutic target for patients with NPC.
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Affiliation(s)
- Qiuchan Zhang
- Department of Otorhinolaryngology-Head and Neck Surgery, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Qingyuan, Guangdong 511518, P.R. China
| | - Dongling Lu
- Department of Otorhinolaryngology-Head and Neck Surgery, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Qingyuan, Guangdong 511518, P.R. China
| | - Wenlin Liu
- Department of Otorhinolaryngology-Head and Neck Surgery, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Qingyuan, Guangdong 511518, P.R. China
| | - Shijie Ye
- Department of Otorhinolaryngology-Head and Neck Surgery, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Qingyuan, Guangdong 511518, P.R. China
| | - Huanping Guo
- Department of Otorhinolaryngology-Head and Neck Surgery, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Qingyuan, Guangdong 511518, P.R. China
| | - Tianyi Liao
- Department of Otorhinolaryngology-Head and Neck Surgery, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Qingyuan, Guangdong 511518, P.R. China
| | - Cuifang Chen
- Department of Otorhinolaryngology-Head and Neck Surgery, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Qingyuan, Guangdong 511518, P.R. China
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Kelliher MT, Saunders HA, Wildonger J. Microtubule control of functional architecture in neurons. Curr Opin Neurobiol 2019; 57:39-45. [PMID: 30738328 DOI: 10.1016/j.conb.2019.01.003] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 01/04/2019] [Accepted: 01/07/2019] [Indexed: 01/20/2023]
Abstract
Neurons are exquisitely polarized cells whose structure and function relies on microtubules. Microtubules in signal-receiving dendrites and signal-sending axons differ in their organization and microtubule-associated proteins. These differences, coupled with microtubule post-translational modifications, combine to locally regulate intracellular transport, morphology, and function. Recent discoveries provide new insight into the regulation of non-centrosomal microtubule arrays in neurons, the relationship between microtubule acetylation and mechanosensation, and the spatial patterning of microtubules that regulates motor activity and cargo delivery in axons and dendrites. Together, these new studies bring us closer to understanding how microtubule function is locally tuned to match the specialized tasks associated with signal reception and transmission.
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Affiliation(s)
- Michael T Kelliher
- Integrated Program in Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA; Biochemistry Department, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Harriet Aj Saunders
- Integrated Program in Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA; Biochemistry Department, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Jill Wildonger
- Biochemistry Department, University of Wisconsin-Madison, Madison, WI 53706, USA.
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