51
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Lawrence EJ, Arpag G, Arnaiz C, Zanic M. SSNA1 stabilizes dynamic microtubules and detects microtubule damage. eLife 2021; 10:67282. [PMID: 34970964 PMCID: PMC8798045 DOI: 10.7554/elife.67282] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 12/30/2021] [Indexed: 11/13/2022] Open
Abstract
Sjögren’s syndrome nuclear autoantigen-1 (SSNA1/NA14) is a microtubule-associated protein with important functions in cilia, dividing cells, and developing neurons. However, the direct effects of SSNA1 on microtubules are not known. We employed in vitro reconstitution with purified proteins and TIRF microscopy to investigate the activity of human SSNA1 on dynamic microtubule ends and lattices. Our results show that SSNA1 modulates all parameters of microtubule dynamic instability—slowing down the rates of growth, shrinkage, and catastrophe, and promoting rescue. We find that SSNA1 forms stretches along growing microtubule ends and binds cooperatively to the microtubule lattice. Furthermore, SSNA1 is enriched on microtubule damage sites, occurring both naturally, as well as induced by the microtubule severing enzyme spastin. Finally, SSNA1 binding protects microtubules against spastin’s severing activity. Taken together, our results demonstrate that SSNA1 is both a potent microtubule-stabilizing protein and a novel sensor of microtubule damage; activities that likely underlie SSNA1’s functions on microtubule structures in cells.
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Affiliation(s)
- Elizabeth J Lawrence
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, United States
| | - Goker Arpag
- Department of Cell and Developmental Biology and Program in Developmental Biology, Vanderbilt University, Nashville, United States
| | - Cayetana Arnaiz
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, United States
| | - Marija Zanic
- Department of Cell and Developmental Biology and Program in Developmental Biology, Vanderbilt University, Nashville, United States
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52
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Dunleavy JEM, O'Connor AE, Okuda H, Merriner DJ, O'Bryan MK. KATNB1 is a master regulator of multiple katanin enzymes in male meiosis and haploid germ cell development. Development 2021; 148:273717. [PMID: 34822718 DOI: 10.1242/dev.199922] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 11/16/2021] [Indexed: 12/14/2022]
Abstract
Katanin microtubule-severing enzymes are crucial executers of microtubule regulation. Here, we have created an allelic loss-of-function series of the katanin regulatory B-subunit KATNB1 in mice. We reveal that KATNB1 is the master regulator of all katanin enzymatic A-subunits during mammalian spermatogenesis, wherein it is required to maintain katanin A-subunit abundance. Our data shows that complete loss of KATNB1 from germ cells is incompatible with sperm production, and we reveal multiple new spermatogenesis functions for KATNB1, including essential roles in male meiosis, acrosome formation, sperm tail assembly, regulation of both the Sertoli and germ cell cytoskeletons during sperm nuclear remodelling, and maintenance of seminiferous epithelium integrity. Collectively, our findings reveal that katanins are able to differentially regulate almost all key microtubule-based structures during mammalian male germ cell development, through the complexing of one master controller, KATNB1, with a 'toolbox' of neofunctionalised katanin A-subunits.
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Affiliation(s)
- Jessica E M Dunleavy
- School of Biological Sciences, Faculty of Science, Monash University, Clayton, VIC, 3800, Australia.,School of BioSciences, Faculty of Science, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Anne E O'Connor
- School of Biological Sciences, Faculty of Science, Monash University, Clayton, VIC, 3800, Australia.,School of BioSciences, Faculty of Science, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Hidenobu Okuda
- School of Biological Sciences, Faculty of Science, Monash University, Clayton, VIC, 3800, Australia
| | - D Jo Merriner
- School of Biological Sciences, Faculty of Science, Monash University, Clayton, VIC, 3800, Australia.,School of BioSciences, Faculty of Science, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Moira K O'Bryan
- School of BioSciences, Faculty of Science, The University of Melbourne, Parkville, VIC, 3010, Australia
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53
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Liu Q, Zhang G, Ji Z, Lin H. Molecular and cellular mechanisms of spastin in neural development and disease (Review). Int J Mol Med 2021; 48:218. [PMID: 34664680 PMCID: PMC8547542 DOI: 10.3892/ijmm.2021.5051] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 09/29/2021] [Indexed: 12/26/2022] Open
Abstract
Spastin is a microtubule (MT)‑severing enzyme identified from mutations of hereditary spastic paraplegia in 1999 and extensive studies indicate its vital role in various cellular activities. In the past two decades, efforts have been made to understand the underlying molecular mechanisms of how spastin is linked to neural development and disease. Recent studies on spastin have unraveled the mechanistic processes of its MT‑severing activity and revealed that spastin acts as an MT amplifier to mediate its remodeling, thus providing valuable insight into the molecular roles of spastin under physiological conditions. In addition, recent research has revealed multiple novel molecular mechanisms of spastin in cellular biological pathways, including endoplasmic reticulum shaping, calcium trafficking, fatty acid trafficking, as well as endosomal fission and trafficking. These processes are closely involved in axonal and dendritic development and maintenance. The current review presents recent biological advances regarding the molecular mechanisms of spastin at the cellular level and provides insight into how it affects neural development and disease.
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Affiliation(s)
- Qiuling Liu
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong 510630, P.R. China
| | - Guowei Zhang
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong 510630, P.R. China
| | - Zhisheng Ji
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong 510630, P.R. China
| | - Hongsheng Lin
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong 510630, P.R. China
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54
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Luo J, Hu Q, Gou M, Liu X, Qin Y, Zhu J, Cai C, Tian T, Tu Z, Du Y, Deng H. Expression of Microtubule-Associated Proteins in Relation to Prognosis and Efficacy of Immunotherapy in Non-Small Cell Lung Cancer. Front Oncol 2021; 11:680402. [PMID: 34660263 PMCID: PMC8517487 DOI: 10.3389/fonc.2021.680402] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Accepted: 09/06/2021] [Indexed: 02/05/2023] Open
Abstract
Background Microtubule-associated proteins (MAPs) have been considered to play significant roles in the tumor evolution of non-small cell lung cancer (NSCLC). Nevertheless, mRNA transcription levels and prognostic value of distinct MAPs in patients with NSCLC remain to be clarified. Methods In this study, the Oncomine database, Gene Expression Profiling Interactive Analysis (GEPIA) database, and Human Protein Atlas were utilized to analyze the relationship between mRNA/protein expression of different MAPs and clinical characteristics in NSCLC patients, including tumor type and pathological stage. The correlation between the transcription level of MAPs and overall survival (OS) of NSCLC patients was analyzed by Kaplan–Meier plotter. Besides, 50 frequently altered neighbor genes of the MAPs were screened out, and a network has been constructed via the cBioPortal and Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) dataset. Meanwhile, we performed Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis on the expression data of MAPs and their 50 frequently altered neighbor genes in NSCLC tissues. Furthermore, The Cancer Immunome Atlas (TCIA) was utilized to analyze the relationship between MAP expression and the response to immunotherapy. Finally, we used reverse transcription-quantitative polymerase chain reaction (RT-qPCR) to verify the expression of MAPs in 20 patients with NSCLC. Results The present study discovered that the mRNA transcription levels of MAP7/7D2 were enriched in NSCLC tissues, while those of the MAP2/4/6/7D3 were lower in NSCLC specimens than those in control specimens. The mRNA transcription level of MAP6 was significantly associated with the advanced stage of NSCLC. Besides, survival analysis indicated that higher mRNA expressions of MAP2/4/6/7/7D3 were correlated considerably with favorable OS of NSCLC patients, whereas increased mRNA expression levels of MAP1A/1S were associated with poor OS. Moreover, the expression of MAP1A/1B/1S/4/6/7D1/7D3 was significantly correlated with immunophenoscore (IPS) in NSCLC patients. Conclusions Our analysis indicated that MAP1A/1S could serve as potential personalized therapeutic targets for patients with NSCLC, and the enriched MAP2/4/6/7/7D3 expression could serve as a biomarker for favorable prognosis in NSCLC. Besides, the expression of MAP1A/1B/1S/4/6/7D1/7D3 was closely related to the response to immunotherapy. Taken together, MAP expression has potential application value in the clinical treatment and prognosis assessment of NSCLC patients, and further verifiable experiments can be conducted to verify our results.
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Affiliation(s)
- Jieyan Luo
- Department of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu, China
| | - Qipeng Hu
- Department of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu, China
| | - Maling Gou
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Xiaoke Liu
- Department of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu, China
| | - Yi Qin
- Department of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu, China
| | - Jiao Zhu
- Department of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu, China
| | - Chengzhi Cai
- Department of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu, China
| | - Tian Tian
- Department of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu, China
| | - Zegui Tu
- Department of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu, China
| | - Yijia Du
- Department of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu, China
| | - Hongxin Deng
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center for Biotherapy, Chengdu, China
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55
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The Aneugenicity of Ketone Bodies in Colon Epithelial Cells Is Mediated by Microtubule Hyperacetylation and Is Blocked by Resveratrol. Int J Mol Sci 2021; 22:ijms22179397. [PMID: 34502304 PMCID: PMC8430621 DOI: 10.3390/ijms22179397] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 08/25/2021] [Accepted: 08/25/2021] [Indexed: 01/23/2023] Open
Abstract
Diabetes mellitus (DM) is considered to be associated with an increased risk of colorectal cancer. Recent studies have also revealed that tubulin hyperacetylation is caused by a diabetic status and we have reported previously that, under microtubule hyperacetylation, a microtubule severing protein, katanin-like (KL) 1, is upregulated and contributes to tumorigenesis. To further explore this phenomenon, we tested the effects of the ketone bodies, acetoacetate and β-hydroxybutyrate, in colon and fibroblast cells. Both induced microtubule hyperacetylation that responded differently to a histone deacetylase 3 knockdown. These two ketone bodies also generated intracellular reactive oxygen species (ROS) and hyperacetylation was commonly inhibited by ROS inhibitors. In a human fibroblast-based microtubule sensitivity test, only the KL1 human katanin family member showed activation by both ketone bodies. In primary cultured colon epithelial cells, these ketone bodies reduced the tau protein level and induced KL1- and α-tubulin acetyltransferase 1 (ATAT1)-dependent micronucleation. Resveratrol, known for its tumor preventive and tubulin deacetylation effects, inhibited this micronucleation. Our current data thus suggest that the microtubule hyperacetylation induced by ketone bodies may be a causal factor linking DM to colorectal carcinogenesis and may also represent an adverse effect of them that needs to be controlled if they are used as therapeutics.
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56
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Damre M, Dayananda A, Varikoti RA, Stan G, Dima RI. Factors underlying asymmetric pore dynamics of disaggregase and microtubule-severing AAA+ machines. Biophys J 2021; 120:3437-3454. [PMID: 34181904 PMCID: PMC8391056 DOI: 10.1016/j.bpj.2021.05.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 04/11/2021] [Accepted: 05/19/2021] [Indexed: 11/26/2022] Open
Abstract
Disaggregation and microtubule-severing nanomachines from the AAA+ (ATPases associated with various cellular activities) superfamily assemble into ring-shaped hexamers that enable protein remodeling by coupling large-scale conformational changes with application of mechanical forces within a central pore by loops protruding within the pore. We probed the asymmetric pore motions and intraring interactions that support them by performing extensive molecular dynamics simulations of single-ring severing proteins and the double-ring disaggregase ClpB. Simulations reveal that dynamic stability of hexameric pores of severing proteins and of the nucleotide-binding domain 1 (NBD1) ring of ClpB, which belong to the same clade, involves a network of salt bridges that connect conserved motifs of central pore loops. Clustering analysis of ClpB highlights correlated motions of domains of neighboring protomers supporting strong interprotomer collaboration. Severing proteins have weaker interprotomer coupling and stronger intraprotomer stabilization through salt bridges involving pore loops. Distinct mechanisms are identified in the NBD2 ring of ClpB involving weaker interprotomer coupling through salt bridges formed by noncanonical loops and stronger intraprotomer coupling. Analysis of collective motions of PL1 loops indicates that the largest amplitude motions in the spiral complex of spastin and ClpB involve axial excursions of the loops, whereas for katanin they involve opening and closing of the central pore. All three motors execute primarily axial excursions in the ring complex. These results suggest distinct substrate processing mechanisms of remodeling and translocation by ClpB and spastin compared to katanin, thus providing dynamic support for the differential action of the two severing proteins. Relaxation dynamics of the distance between the PL1 loops and the center of mass of protomers reveals observation-time-dependent dynamics, leading to predicted relaxation times of tens to hundreds of microseconds on millisecond experimental timescales. For ClpB, the predicted relaxation time is in excellent agreement with the extracted time from smFRET experiments.
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Affiliation(s)
- Mangesh Damre
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio
| | - Ashan Dayananda
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio
| | | | - George Stan
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio.
| | - Ruxandra I Dima
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio.
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57
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Lynn NA, Martinez E, Nguyen H, Torres JZ. The Mammalian Family of Katanin Microtubule-Severing Enzymes. Front Cell Dev Biol 2021; 9:692040. [PMID: 34414183 PMCID: PMC8369831 DOI: 10.3389/fcell.2021.692040] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 06/04/2021] [Indexed: 12/12/2022] Open
Abstract
The katanin family of microtubule-severing enzymes is critical for cytoskeletal rearrangements that affect key cellular processes like division, migration, signaling, and homeostasis. In humans, aberrant expression, or dysfunction of the katanins, is linked to developmental, proliferative, and neurodegenerative disorders. Here, we review current knowledge on the mammalian family of katanins, including an overview of evolutionary conservation, functional domain organization, and the mechanisms that regulate katanin activity. We assess the function of katanins in dividing and non-dividing cells and how their dysregulation promotes impaired ciliary signaling and defects in developmental programs (corticogenesis, gametogenesis, and neurodevelopment) and contributes to neurodegeneration and cancer. We conclude with perspectives on future katanin research that will advance our understanding of this exciting and dynamic class of disease-associated enzymes.
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Affiliation(s)
- Nicole A. Lynn
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, United States
| | - Emily Martinez
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, United States
| | - Hieu Nguyen
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, United States
| | - Jorge Z. Torres
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, United States
- Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA, United States
- Jonsson Comprehensive Cancer Center, University of California, Los Angeles, Los Angeles, CA, United States
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58
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Wang H, Sun J, Yang F, Weng Y, Chen P, Du S, Wei A, Li Y. CsKTN1 for a katanin p60 subunit is associated with the regulation of fruit elongation in cucumber (Cucumis sativus L.). TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2021; 134:2429-2441. [PMID: 34043036 DOI: 10.1007/s00122-021-03833-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 04/03/2021] [Indexed: 06/12/2023]
Abstract
We identified a short fruit3 (sf3) mutant in cucumber. Map-based cloning revealed that CsKTN1 gene encodes a katanin p60 subunit, which is associated with the regulation of fruit elongation. Fruit length is an important horticultural trait for both fruit yield and quality of cucumber (Cucumis sativus L.). Knowledge on the molecular regulation of fruit elongation in cucumber is very limited. In this study, we identified and characterized a cucumber short fruit3 (sf3) mutant. Histological examination indicated that the shorter fruit in the mutant was due to reduced cell numbers. Genetic analysis revealed that the phenotype of the sf3 mutant was controlled by a single gene with semi-dominant inheritance. By map-based cloning and Arabidopsis genetic transformation, we showed that Sf3 was a homolog of KTN1 (CsKTN1) encoding a katanin p60 subunit. A non-synonymous mutation in the fifth exon of CsKTN1 resulted in an amino acid substitution from Serine in the wild type to Phenylalanine in the sf3 mutant. CsKTN1 expressed in all tissues of both the wild type and the sf3 mutant. However, there was no significant difference in CsKTN1 expression levels between the wild type and the sf3 mutant. The hormone quantitation and RNA-seq analysis suggested that auxin and gibberellin contents are decreased in sf3 by changing the expression levels of genes related with auxin and gibberellin metabolism and signaling. This work helps understand the function of the katanin and the molecular mechanisms of fruit growth regulation in cucumber.
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Affiliation(s)
- Hui Wang
- College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Jing Sun
- College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Fan Yang
- College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Yiqun Weng
- Horticulture Department, USDA-ARS Vegetable Crops Research Unit, University of Wisconsin, Madison, WI, 53706, USA
| | - Peng Chen
- College of Life Science, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Shengli Du
- Tianjin Vegetable Research Center, Tianjin, 300192, China
- National Key Laboratory of Vegetable Germplasm Innovation, Tianjin, 300192, China
| | - Aimin Wei
- Tianjin Vegetable Research Center, Tianjin, 300192, China.
- National Key Laboratory of Vegetable Germplasm Innovation, Tianjin, 300192, China.
| | - Yuhong Li
- College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China.
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59
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Huang J, Liang Z, Guan C, Hua S, Jiang K. WDR62 regulates spindle dynamics as an adaptor protein between TPX2/Aurora A and katanin. J Cell Biol 2021; 220:212395. [PMID: 34137789 PMCID: PMC8240853 DOI: 10.1083/jcb.202007167] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 04/12/2021] [Accepted: 05/18/2021] [Indexed: 12/21/2022] Open
Abstract
WDR62 is a microcephaly-related, microtubule (MT)-associated protein (MAP) that localizes to the spindle pole and regulates spindle organization, but the underlying mechanisms remain elusive. Here, we show that WDR62 regulates spindle dynamics by recruiting katanin to the spindle pole and further reveal a TPX2–Aurora A–WDR62–katanin axis in cells. By combining cellular and in vitro experiments, we demonstrate that WDR62 shows preference for curved segments of dynamic GDP-MTs, as well as GMPCPP- and paclitaxel-stabilized MTs, suggesting that it recognizes extended MT lattice. Consistent with this property, WDR62 alone is inefficient in recruiting katanin to GDP-MTs, while WDR62 complexed with TPX2/Aurora A can potently promote katanin-mediated severing of GDP-MTs in vitro. In addition, the MT-binding affinity of WDR62 is autoinhibited through JNK phosphorylation-induced intramolecular interaction. We propose that WDR62 is an atypical MAP and functions as an adaptor protein between its recruiting factor TPX2/Aurora A and the effector katanin to orchestrate the regulation of spindle dynamics.
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Affiliation(s)
- Junjie Huang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China.,Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan, China
| | - Zhuobi Liang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China.,Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan, China
| | - Cuirong Guan
- The State Key Laboratory Breeding Base of Basic Science of Stomatology and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China.,Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan, China
| | - Shasha Hua
- The State Key Laboratory Breeding Base of Basic Science of Stomatology and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China.,Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan, China
| | - Kai Jiang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China.,Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan, China
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60
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An anchoring complex recruits katanin for microtubule severing at the plant cortical nucleation sites. Nat Commun 2021; 12:3687. [PMID: 34140499 PMCID: PMC8211667 DOI: 10.1038/s41467-021-24067-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 05/25/2021] [Indexed: 02/05/2023] Open
Abstract
Microtubules are severed by katanin at distinct cellular locations to facilitate reorientation or amplification of dynamic microtubule arrays, but katanin targeting mechanisms are poorly understood. Here we show that a centrosomal microtubule-anchoring complex is used to recruit katanin in acentrosomal plant cells. The conserved protein complex of Msd1 (also known as SSX2IP) and Wdr8 is localized at microtubule nucleation sites along the microtubule lattice in interphase Arabidopsis cells. Katanin is recruited to these sites for efficient release of newly formed daughter microtubules. Our cell biological and genetic studies demonstrate that Msd1-Wdr8 acts as a specific katanin recruitment factor to cortical nucleation sites (but not to microtubule crossover sites) and stabilizes the association of daughter microtubule minus ends to their nucleation sites until they become severed by katanin. Molecular coupling of sequential anchoring and severing events by the evolutionarily conserved complex renders microtubule release under tight control of katanin activity.
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61
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Mani N, Wijeratne SS, Subramanian R. Micron-scale geometrical features of microtubules as regulators of microtubule organization. eLife 2021; 10:e63880. [PMID: 34114950 PMCID: PMC8195601 DOI: 10.7554/elife.63880] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 06/02/2021] [Indexed: 12/20/2022] Open
Abstract
The organization of micron-sized, multi-microtubule arrays from individual microtubules is essential for diverse cellular functions. The microtubule polymer is largely viewed as a passive building block during the organization process. An exception is the 'tubulin code' where alterations to tubulin at the amino acid level can influence the activity of microtubule-associated proteins. Recent studies reveal that micron-scale geometrical features of individual microtubules and polymer networks, such as microtubule length, overlap length, contact angle, and lattice defects, can also regulate the activity of microtubule-associated proteins and modulate polymer dynamics. We discuss how the interplay between such geometrical properties of the microtubule lattice and the activity of associated proteins direct multiple aspects of array organization, from microtubule nucleation and coalignment to specification of array dimensions and remodeling of dynamic networks. The mechanisms reviewed here highlight micron-sized features of microtubules as critical parameters to be routinely investigated in the study of microtubule self-organization.
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Affiliation(s)
- Nandini Mani
- Department of Molecular Biology, Massachusetts General HospitalBostonUnited States
- Department of Genetics, Harvard Medical SchoolBostonUnited States
| | - Sithara S Wijeratne
- Department of Molecular Biology, Massachusetts General HospitalBostonUnited States
- Department of Genetics, Harvard Medical SchoolBostonUnited States
| | - Radhika Subramanian
- Department of Molecular Biology, Massachusetts General HospitalBostonUnited States
- Department of Genetics, Harvard Medical SchoolBostonUnited States
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62
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Barisic M, Rajendraprasad G, Steblyanko Y. The metaphase spindle at steady state - Mechanism and functions of microtubule poleward flux. Semin Cell Dev Biol 2021; 117:99-117. [PMID: 34053864 DOI: 10.1016/j.semcdb.2021.05.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 05/13/2021] [Accepted: 05/13/2021] [Indexed: 11/24/2022]
Abstract
The mitotic spindle is a bipolar cellular structure, built from tubulin polymers, called microtubules, and interacting proteins. This macromolecular machine orchestrates chromosome segregation, thereby ensuring accurate distribution of genetic material into the two daughter cells during cell division. Powered by GTP hydrolysis upon tubulin polymerization, the microtubule ends exhibit a metastable behavior known as the dynamic instability, during which they stochastically switch between the growth and shrinkage phases. In the context of the mitotic spindle, dynamic instability is furthermore regulated by microtubule-associated proteins and motor proteins, which enables the spindle to undergo profound changes during mitosis. This highly dynamic behavior is essential for chromosome capture and congression in prometaphase, as well as for chromosome alignment to the spindle equator in metaphase and their segregation in anaphase. In this review we focus on the mechanisms underlying microtubule dynamics and sliding and their importance for the maintenance of shape, structure and dynamics of the metaphase spindle. We discuss how these spindle properties are related to the phenomenon of microtubule poleward flux, highlighting its highly cooperative molecular basis and role in keeping the metaphase spindle at a steady state.
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Affiliation(s)
- Marin Barisic
- Cell Division and Cytoskeleton, Danish Cancer Society Research Center (DCRC), Strandboulevarden 49, 2100 Copenhagen, Denmark; Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark.
| | - Girish Rajendraprasad
- Cell Division and Cytoskeleton, Danish Cancer Society Research Center (DCRC), Strandboulevarden 49, 2100 Copenhagen, Denmark
| | - Yulia Steblyanko
- Cell Division and Cytoskeleton, Danish Cancer Society Research Center (DCRC), Strandboulevarden 49, 2100 Copenhagen, Denmark
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63
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Sun L, Cui L, Liu Z, Wang Q, Xue Z, Wu M, Sun T, Mao D, Ni J, Pastor-Pareja JC, Liang X. Katanin p60-like 1 sculpts the cytoskeleton in mechanosensory cilia. J Cell Biol 2021; 220:211570. [PMID: 33263729 PMCID: PMC7717695 DOI: 10.1083/jcb.202004184] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 09/28/2020] [Accepted: 10/20/2020] [Indexed: 12/20/2022] Open
Abstract
Mechanoreceptor cells develop a specialized cytoskeleton that plays structural and sensory roles at the site of mechanotransduction. However, little is known about how the cytoskeleton is organized and formed. Using electron tomography and live-cell imaging, we resolve the 3D structure and dynamics of the microtubule-based cytoskeleton in fly campaniform mechanosensory cilia. Investigating the formation of the cytoskeleton, we find that katanin p60-like 1 (kat-60L1), a neuronal type of microtubule-severing enzyme, serves two functions. First, it amplifies the mass of microtubules to form the dense microtubule arrays inside the sensory cilia. Second, it generates short microtubules that are required to build the nanoscopic cytoskeleton at the mechanotransduction site. Additional analyses further reveal the functional roles of Patronin and other potential factors in the local regulatory network. In all, our results characterize the specialized cytoskeleton in fly external mechanosensory cilia at near-molecular resolution and provide mechanistic insights into how it is formed.
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Affiliation(s)
- Landi Sun
- Tsinghua-Peking Joint Center for Life Science, School of Life Sciences, Tsinghua University, Beijing, China
| | - Lihong Cui
- Tsinghua-Peking Joint Center for Life Science, School of Life Sciences, Tsinghua University, Beijing, China
| | - Zhen Liu
- Tsinghua-Peking Joint Center for Life Science, School of Life Sciences, Tsinghua University, Beijing, China
| | - Qixuan Wang
- Tsinghua-Peking Joint Center for Life Science, School of Life Sciences, Tsinghua University, Beijing, China
| | - Zhaoyu Xue
- Tsinghua-Peking Joint Center for Life Science, School of Life Sciences, Tsinghua University, Beijing, China
| | - Menghua Wu
- Tsinghua-Peking Joint Center for Life Science, School of Life Sciences, Tsinghua University, Beijing, China
| | - Tianhui Sun
- Tsinghua-Peking Joint Center for Life Science, School of Life Sciences, Tsinghua University, Beijing, China
| | - Decai Mao
- School of Medicine, Tsinghua University, Beijing, China
| | - Jianquan Ni
- School of Medicine, Tsinghua University, Beijing, China
| | - José Carlos Pastor-Pareja
- Tsinghua-Peking Joint Center for Life Science, School of Life Sciences, Tsinghua University, Beijing, China
| | - Xin Liang
- Tsinghua-Peking Joint Center for Life Science, School of Life Sciences, Tsinghua University, Beijing, China
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64
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Szatkowski L, Varikoti RA, Dima RI. Modeling the Mechanical Response of Microtubule Lattices to Pressure. J Phys Chem B 2021; 125:5009-5021. [PMID: 33970630 DOI: 10.1021/acs.jpcb.1c01770] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Microtubules, the largest and stiffest filaments of the cytoskeleton, have to be well adapted to the high levels of crowdedness in cells to perform their multitude of functions. Furthermore, fundamental processes that involve microtubules, such as the maintenance of the cellular shape and cellular motion, are known to be highly dependent on external pressure. In light of the importance of pressure for the functioning of microtubules, numerous studies interrogated the response of these cytoskeletal filaments to osmotic pressure, resulting from crowding by osmolytes, such as poly(ethylene glycol)/poly(ethylene oxide) (PEG/PEO) molecules, or to direct applied pressure. The interpretation of experiments is usually based on the assumptions that PEG molecules have unfavorable interactions with the microtubule lattices and that the behavior of microtubules under pressure can be described by using continuous models. We probed directly these two assumptions. First, we characterized the interaction between the main interfaces in a microtubule filament and PEG molecules of various sizes using a combination of docking and molecular dynamics simulations. Second, we studied the response of a microtubule filament to compression using a coarse-grained model that allows for the breaking of lattice interfaces. Our results show that medium length PEG molecules do not alter the energetics of the lateral interfaces in microtubules but rather target and can penetrate into the voids between tubulin monomers at these interfaces, which can lead to a rapid loss of lateral interfaces under pressure. Compression of a microtubule under conditions corresponding to high osmotic pressure results in the formation of the deformed phase found in experiments. Our simulations show that the breaking of lateral interfaces, rather than the buckling of the filament inferred from the continuous models, accounts for the deformation.
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Affiliation(s)
- Lukasz Szatkowski
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States.,Division of Science, Mathematics, and Engineering, University of South Carolina Sumter, Sumter, South Carolina 29150, United States
| | - Rohith Anand Varikoti
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Ruxandra I Dima
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
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65
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Baker L, Tar M, Kramer AH, Villegas GA, Charafeddine RA, Vafaeva O, Nacharaju P, Friedman J, Davies KP, Sharp DJ. Fidgetin-like 2 negatively regulates axonal growth and can be targeted to promote functional nerve regeneration. JCI Insight 2021; 6:138484. [PMID: 33872220 PMCID: PMC8262307 DOI: 10.1172/jci.insight.138484] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 04/01/2021] [Indexed: 02/05/2023] Open
Abstract
The microtubule (MT) cytoskeleton plays a critical role in axon growth and guidance. Here, we identify the MT-severing enzyme fidgetin-like 2 (FL2) as a negative regulator of axon regeneration and a therapeutic target for promoting nerve regeneration after injury. Genetic knockout of FL2 in cultured adult dorsal root ganglion neurons resulted in longer axons and attenuated growth cone retraction in response to inhibitory molecules. Given the axonal growth-promoting effects of FL2 depletion in vitro, we tested whether FL2 could be targeted to promote regeneration in a rodent model of cavernous nerve (CN) injury. The CNs are parasympathetic nerves that regulate blood flow to the penis, which are commonly damaged during radical prostatectomy (RP), resulting in erectile dysfunction (ED). Application of FL2-siRNA after CN injury significantly enhanced functional nerve recovery. Remarkably, following bilateral nerve transection, visible and functional nerve regeneration was observed in 7 out of 8 animals treated with FL2-siRNA, while no control-treated animals exhibited regeneration. These studies identify FL2 as a promising therapeutic target for enhancing regeneration after peripheral nerve injury and for mitigating neurogenic ED after RP - a condition for which, at present, only poor treatment options exist.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - David J. Sharp
- Department of Physiology and Biophysics
- Dominick P. Purpura Department of Neuroscience, and
- Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, New York, USA
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66
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Li Y, Deng M, Liu H, Li Y, Chen Y, Jia M, Xue H, Shao J, Zhao J, Qi Y, An L, Yu F, Liu X. ABNORMAL SHOOT 6 interacts with KATANIN 1 and SHADE AVOIDANCE 4 to promote cortical microtubule severing and ordering in Arabidopsis. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2021; 63:646-661. [PMID: 32761943 DOI: 10.1111/jipb.13003] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 08/03/2020] [Indexed: 05/14/2023]
Abstract
Plant interphase cortical microtubules (cMTs) mediate anisotropic cell expansion in response to environmental and developmental cues. In Arabidopsis thaliana, KATANIN 1 (KTN1), the p60 catalytic subunit of the conserved MT-severing enzyme katanin, is essential for cMT ordering and anisotropic cell expansion. However, the regulation of KTN1-mediated cMT severing and ordering remains unclear. In this work, we report that the Arabidopsis IQ67 DOMAIN (IQD) family gene ABNORMAL SHOOT 6 (ABS6) encodes a MT-associated protein. Overexpression of ABS6 leads to elongated cotyledons, directional pavement cell expansion, and highly ordered transverse cMT arrays. Genetic suppressor analysis revealed that ABS6-mediated cMT ordering is dependent on KTN1 and SHADE AVOIDANCE 4 (SAV4). Live imaging of cMT dynamics showed that both ABS6 and SAV4 function as positive regulators of cMT severing. Furthermore, ABS6 directly interacts with KTN1 and SAV4 and promotes their recruitment to the cMTs. Finally, analysis of loss-of-function mutant combinations showed that ABS6, SAV4, and KTN1 work together to ensure the robust ethylene response in the apical hook of dark-grown seedlings. Together, our findings establish ABS6 and SAV4 as positive regulators of cMT severing and ordering, and highlight the role of cMT dynamics in fine-tuning differential growth in plants.
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Affiliation(s)
- Yuanfeng Li
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, 712100, China
| | - Meng Deng
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, 712100, China
| | - Haofeng Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, 712100, China
| | - Yan Li
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, 712100, China
| | - Yu Chen
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, 712100, China
| | - Min Jia
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, 712100, China
| | - Hui Xue
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, 712100, China
| | - Jingxia Shao
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, 712100, China
| | - Jun Zhao
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, 712100, China
| | - Yafei Qi
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, 712100, China
| | - Lijun An
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, 712100, China
| | - Fei Yu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, 712100, China
| | - Xiayan Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, 712100, China
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67
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Parato J, Bartolini F. The microtubule cytoskeleton at the synapse. Neurosci Lett 2021; 753:135850. [PMID: 33775740 DOI: 10.1016/j.neulet.2021.135850] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 03/19/2021] [Accepted: 03/22/2021] [Indexed: 12/13/2022]
Abstract
In neurons, microtubules (MTs) provide routes for transport throughout the cell and structural support for dendrites and axons. Both stable and dynamic MTs are necessary for normal neuronal functions. Research in the last two decades has demonstrated that MTs play additional roles in synaptic structure and function in both pre- and postsynaptic elements. Here, we review current knowledge of the functions that MTs perform in excitatory and inhibitory synapses, as well as in the neuromuscular junction and other specialized synapses, and discuss the implications that this knowledge may have in neurological disease.
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Affiliation(s)
- Julie Parato
- Columbia University Medical Center, Department of Pathology & Cell Biology, 630 West 168(th)Street, P&S 15-421, NY, NY, 10032, United States; SUNY Empire State College, Department of Natural Sciences, 177 Livingston Street, Brooklyn, NY, 11201, United States
| | - Francesca Bartolini
- Columbia University Medical Center, Department of Pathology & Cell Biology, 630 West 168(th)Street, P&S 15-421, NY, NY, 10032, United States.
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68
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To nucleate or not, that is the question in neurons. Neurosci Lett 2021; 751:135806. [PMID: 33705928 DOI: 10.1016/j.neulet.2021.135806] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 02/23/2021] [Accepted: 02/26/2021] [Indexed: 01/19/2023]
Abstract
Microtubules are the structural center of neurons, stretching in overlapping arrays from the cell body to the far reaches of axons and dendrites. They also act as the tracks for long-range transport mediated by dynein and kinesin motors. Transcription and most translation take place in the cell body, and newly made cargoes must be shipped from this site of synthesis to sites of function in axons and dendrites. This constant demand for transport means that the microtubule array must be present without gaps throughout the cell over the lifetime of the animal. This task is made slightly easier in many animals by the relatively long, stable microtubules present in neurons. However, even stable neuronal microtubules have ends that are dynamic, and individual microtubules typically last on the order of hours, while the neurons around them last a lifetime. "Birth" of new microtubules is therefore required to maintain the neuronal microtubule array. In this review we discuss the nucleation of new microtubules in axons and dendrites, including how and where they are nucleated. In addition, it is becoming clear that neuronal microtubule nucleation is highly regulated, with unexpected machinery impinging on the decision of whether nucleation sites are active or inactive through space and time.
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69
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Loss of Coiled-Coil Protein Cep55 Impairs Neural Stem Cell Abscission and Results in p53-Dependent Apoptosis in Developing Cortex. J Neurosci 2021; 41:3344-3365. [PMID: 33622776 DOI: 10.1523/jneurosci.1955-20.2021] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 12/24/2020] [Accepted: 02/13/2021] [Indexed: 12/23/2022] Open
Abstract
To build the brain, embryonic neural stem cells (NSCs) tightly regulate their cell divisions, undergoing a polarized form of cytokinesis that is poorly understood. Cytokinetic abscission is mediated by the midbody to sever the daughter cells at the apical membrane. In cell lines, the coiled-coil protein Cep55 was reported to be required for abscission. Mutations of Cep55 in humans cause a variety of cortical malformations. However, its role in the specialized divisions of NSCs is unclear. Here, we elucidate the roles of Cep55 in abscission and brain development. KO of Cep55 in mice causes abscission defects in neural and non-neural cell types, and postnatal lethality. The brain is disproportionately affected, with severe microcephaly at birth. Quantitative analyses of abscission in fixed and live cortical NSCs show that Cep55 acts to increase the speed and success rate of abscission, by facilitating ESCRT recruitment and timely microtubule disassembly. However, most NSCs complete abscission successfully in the absence of Cep55 Those that fail show a tissue-specific response: binucleate NSCs and neurons elevate p53, but binucleate fibroblasts do not. This leads to massive apoptosis in the brain, but not other tissues. Double KO of both p53 and Cep55 blocks apoptosis but only partially rescues Cep55 -/- brain size. This may be because of the persistent NSC cell division defects and p53-independent premature cell cycle exit. This work adds to emerging evidence that abscission regulation and error tolerance vary by cell type and are especially crucial in neural stem cells as they build the brain.SIGNIFICANCE STATEMENT During brain growth, embryonic neural stem cells (NSCs) must divide many times. In the last step of cell division, the daughter cell severs its connection to the mother stem cell, a process called abscission. The protein Cep55 is thought to be essential for recruiting proteins to the mother-daughter cell connection to complete abscission. We find that Cep55 mutants have very small brains with disturbed structure, but almost normal size bodies. NSC abscission can occur, but it is slower than normal, and failures are increased. Furthermore, NSCs that do fail abscission activate a signal for programmed cell death, whereas non-neural cells do not. Blocking this signal only partly restores brain growth, showing that regulation of abscission is crucial for brain development.
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70
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Bodakuntla S, Janke C, Magiera MM. Tubulin polyglutamylation, a regulator of microtubule functions, can cause neurodegeneration. Neurosci Lett 2021; 746:135656. [PMID: 33482309 DOI: 10.1016/j.neulet.2021.135656] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 01/05/2021] [Accepted: 01/07/2021] [Indexed: 02/07/2023]
Abstract
Neurodegenerative diseases lead to a progressive demise of neuronal functions that ultimately results in neuronal death. Besides a large variety of molecular pathways that have been linked to the degeneration of neurons, dysfunctions of the microtubule cytoskeleton are common features of many human neurodegenerative disorders. Yet, it is unclear whether microtubule dysfunctions are causative, or mere bystanders in the disease progression. A so-far little explored regulatory mechanism of the microtubule cytoskeleton, the posttranslational modifications of tubulin, emerge as candidate mechanisms involved in neuronal dysfunction, and thus, degeneration. Here we review the role of tubulin polyglutamylation, a prominent modification of neuronal microtubules. We discuss the current understanding of how polyglutamylation controls microtubule functions in healthy neurons, and how deregulation of this modification leads to neurodegeneration in mice and humans.
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Affiliation(s)
- Satish Bodakuntla
- Institut Curie, PSL Research University, CNRS UMR3348, F-91401 Orsay, France; Université Paris-Saclay, CNRS UMR3348, F-91401 Orsay, France
| | - Carsten Janke
- Institut Curie, PSL Research University, CNRS UMR3348, F-91401 Orsay, France; Université Paris-Saclay, CNRS UMR3348, F-91401 Orsay, France.
| | - Maria M Magiera
- Institut Curie, PSL Research University, CNRS UMR3348, F-91401 Orsay, France; Université Paris-Saclay, CNRS UMR3348, F-91401 Orsay, France.
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71
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Vemu A, Szczesna E, Roll-Mecak A. In Vitro Reconstitution Assays of Microtubule Amplification and Lattice Repair by the Microtubule-Severing Enzymes Katanin and Spastin. Methods Mol Biol 2021; 2101:27-38. [PMID: 31879896 DOI: 10.1007/978-1-0716-0219-5_3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Microtubules are non-covalent dynamic polymers essential for the life of all eukaryotic cells. Their dynamic behavior is regulated by a large array of cellular effectors. In vitro microtubule assays have been instrumental in dissecting the mechanism of microtubule-associated proteins. In this chapter, we focus on microtubule-severing enzymes katanin and spastin. They are AAA ATPases that generate internal breaks in microtubules by extracting tubulin dimers out of the microtubule lattice. We present protocols for TIRF microscopy-based assays that were instrumental in proving that these enzymes not only sever microtubules but also remodel the microtubule lattice by promoting the exchange of lattice GDP-tubulin with GTP-tubulin from the soluble pool. This activity can modulate microtubule dynamics and support microtubule-dependent microtubule amplification in the absence of a nucleating factor.
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Affiliation(s)
- Annapurna Vemu
- Cell Biology and Biophysics Unit, Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA
| | - Ewa Szczesna
- Cell Biology and Biophysics Unit, Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA
| | - Antonina Roll-Mecak
- Cell Biology and Biophysics Unit, Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA. .,Biochemistry and Biophysics Center, National Heart, Lung and Blood Institute, Bethesda, MD, USA.
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72
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Dong Z, Chen X, Li Y, Zhuo R, Lai X, Liu M. Microtubule Severing Protein Fignl2 Contributes to Endothelial and Neuronal Branching in Zebrafish Development. Front Cell Dev Biol 2021; 8:593234. [PMID: 33585441 PMCID: PMC7873885 DOI: 10.3389/fcell.2020.593234] [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: 08/10/2020] [Accepted: 12/21/2020] [Indexed: 11/13/2022] Open
Abstract
Previously, fidgetin (fign) and its family members fidgetin-like 1 (fignl1) and fidgetin-like 2 (fignl2) were found to be highly expressed during zebrafish brain development, suggesting their functions in the nervous system. In this study, we report the effects of loss-of-function of these genes on development. We designed and identified single-guide RNAs targeted to generate fign, fignl1, and fignl2 mutants and then observed the overall morphological and behavioral changes. Our findings showed that while fign and fignl1 null mutants displayed no significant defects, fignl2 null zebrafish mutants displayed pericardial edema, reduced heart rate, and smaller eyes; fignl2 null mutants responded to the light-darkness shift with a lower swimming velocity. fignl2 mRNAs were identified in vascular endothelial cells by in situ hybridization and re-analysis of an online dataset of single-cell RNAseq results. Finally, we used morpholino oligonucleotides to confirm that fignl2 knockdown resulted in severe heart edema, which was caused by abnormal vascular branching. The zebrafish fignl2 morphants also showed longer axonal length and more branches of caudal primary neurons. Taken together, we summarize that Fignl2 functions on cellular branches in endothelial cells and neurons. This study reported for the first time that the microtubule-severing protein Fignl2 contributes to cell branching during development.
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Affiliation(s)
- Zhangji Dong
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Xu Chen
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Yuanyuan Li
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Run Zhuo
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Xiaona Lai
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Mei Liu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
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73
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Wang L, Yan M, Li H, Wu S, Ge R, Wong CKC, Silvestrini B, Sun F, Cheng CY. The Non-hormonal Male Contraceptive Adjudin Exerts its Effects via MAPs and Signaling Proteins mTORC1/rpS6 and FAK-Y407. Endocrinology 2021; 162:5936120. [PMID: 33094326 PMCID: PMC8244566 DOI: 10.1210/endocr/bqaa196] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Indexed: 12/12/2022]
Abstract
Adjudin, 1-(2,4-dichlorobenzyl)-1H-indazole-3-carbohydrazide (formerly called AF-2364), is a nonhormonal male contraceptive, since it effectively induces reversible male infertility without perturbing the serum concentrations of follicle stimulating hormone (FSH), testosterone, and inhibin B based on studies in rats and rabbits. Adjudin was shown to exert its effects preferentially by perturbing the testis-specific actin-rich adherens junction (AJ) at the Sertoli-spermatid interface known as apical ectoplasmic specialization (apical ES), thereby effectively inducing spermatid exfoliation. Adjudin did not perturb germ cell development nor germ cell function. Also, it had no effects on Sertoli cell-cell AJ called basal ectoplasmic specialization (basal ES), which, together with tight junction constitute the blood-testis barrier (BTB), unless an acute dose of adjudin was used. Adjudin also did not perturb the population of spermatogonial stem cells nor Sertoli cells in the testis. However, the downstream signaling protein(s) utilized by adjudin to induce transient male infertility remains unexplored. Herein, using adult rats treated with adjudin and monitored changes in the phenotypes across the seminiferous epithelium between 6 and 96 h in parallel with the steady-state protein levels of an array of signaling and cytoskeletal regulatory proteins, recently shown to be involved in apical ES, basal ES and BTB function. It was shown that adjudin exerts its contraceptive effects through changes in microtubule associated proteins (MAPs) and signaling proteins mTORC1/rpS6 and p-FAK-Y407. These findings are important to not only study adjudin-mediated male infertility but also the biology of spermatogenesis.
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Affiliation(s)
- Lingling Wang
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, Jiangsu, China
- The Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York
| | - Ming Yan
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Huitao Li
- The Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Siwen Wu
- The Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Renshan Ge
- The Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Chris K C Wong
- Department of Biology, Croucher Institute for Environmental Sciences, Hong Kong Baptist University, Hong Kong, China
| | | | - Fei Sun
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong, Jiangsu, China
| | - C Yan Cheng
- The Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong, Jiangsu, China
- Correspondence: C. Yan Cheng, PhD, Senior Scientist, The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave, New York, New York 10065. E-mail:
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74
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Yusipov I, Bacalini MG, Kalyakulina A, Krivonosov M, Pirazzini C, Gensous N, Ravaioli F, Milazzo M, Giuliani C, Vedunova M, Fiorito G, Gagliardi A, Polidoro S, Garagnani P, Ivanchenko M, Franceschi C. Age-related DNA methylation changes are sex-specific: a comprehensive assessment. Aging (Albany NY) 2020; 12:24057-24080. [PMID: 33276343 PMCID: PMC7762479 DOI: 10.18632/aging.202251] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 10/19/2020] [Indexed: 12/18/2022]
Abstract
The existence of a sex gap in human health and longevity has been widely documented. Autosomal DNA methylation differences between males and females have been reported, but so far few studies have investigated if DNA methylation is differently affected by aging in males and females. We performed a meta-analysis of 4 large whole blood datasets, comparing 4 aspects of epigenetic age-dependent remodeling between the two sexes: differential methylation, variability, epimutations and entropy. We reported that a large fraction (43%) of sex-associated probes undergoes age-associated DNA methylation changes, and that a limited number of probes show age-by-sex interaction. We experimentally validated 2 regions mapping in FIGN and PRR4 genes and showed sex-specific deviations of their methylation patterns in models of decelerated (centenarians) and accelerated (Down syndrome) aging. While we did not find sex differences in the age-associated increase in epimutations and entropy, we showed that the number of probes having an age-related increase in methylation variability is 15 times higher in males compared to females. Our results can offer new epigenetic tools to study the interaction between aging and sex and can pave the way to the identification of molecular triggers of sex differences in longevity and age-related diseases prevalence.
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Affiliation(s)
- Igor Yusipov
- Institute of Information Technologies, Mathematics and Mechanics, Lobachevsky University, Nizhniy Novgorod, Russia.,Mathematics of Future Technologies Center, Lobachevsky University, Nizhniy Novgorod, Russia
| | | | - Alena Kalyakulina
- Institute of Information Technologies, Mathematics and Mechanics, Lobachevsky University, Nizhniy Novgorod, Russia
| | - Mikhail Krivonosov
- Institute of Information Technologies, Mathematics and Mechanics, Lobachevsky University, Nizhniy Novgorod, Russia
| | - Chiara Pirazzini
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy
| | - Noémie Gensous
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), Alma Mater Studiorum – University of Bologna, Bologna, Italy
| | - Francesco Ravaioli
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), Alma Mater Studiorum – University of Bologna, Bologna, Italy
| | - Maddalena Milazzo
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), Alma Mater Studiorum – University of Bologna, Bologna, Italy
| | - Cristina Giuliani
- Department of Biological, Geological, and Environmental Sciences (BiGeA), Laboratory of Molecular Anthropology and Centre for Genome Biology, University of Bologna, Bologna, Italy.,School of Anthropology and Museum Ethnography, University of Oxford, Oxford, UK
| | - Maria Vedunova
- Institute of Biology and Biomedicine, National Research Lobachevsky State University of Nizhni Novgorod, Nizhni Novgorod, Russia
| | - Giovanni Fiorito
- Department of Biomedical Sciences, University of Sassari, Italy.,Department of Epidemiology and Public Health, MRC/HPA Centre for Environment and Health, School of Public Health, Imperial College London, Norfolk Place, London W2 1PG, UK
| | - Amedeo Gagliardi
- Italian Institute for Genomic Medicine (IIGM), Candiolo 10060, Italy.,Candiolo Cancer Institute, FPO-IRCCS, Candiolo 10060, Italy
| | - Silvia Polidoro
- Department of Epidemiology and Public Health, MRC/HPA Centre for Environment and Health, School of Public Health, Imperial College London, Norfolk Place, London W2 1PG, UK.,Italian Institute for Genomic Medicine (IIGM), Candiolo 10060, Italy.,Candiolo Cancer Institute, FPO-IRCCS, Candiolo 10060, Italy
| | - Paolo Garagnani
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), Alma Mater Studiorum – University of Bologna, Bologna, Italy.,Department of Laboratory Medicine, Clinical Chemistry, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.,Applied Biomedical Research Center (CRBA), Policlinico S.Orsola-Malpighi Polyclinic, Bologna, Italy.,CNR Institute of Molecular Genetics “Luigi Luca Cavalli-Sforza", Unit of Bologna, Bologna, Italy
| | - Mikhail Ivanchenko
- Institute of Information Technologies, Mathematics and Mechanics, Lobachevsky University, Nizhniy Novgorod, Russia.,Mathematics of Future Technologies Center, Lobachevsky University, Nizhniy Novgorod, Russia
| | - Claudio Franceschi
- Institute of Information Technologies, Mathematics and Mechanics, Lobachevsky University, Nizhniy Novgorod, Russia
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75
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Wang L, Yan M, Wong CKC, Ge R, Wu X, Sun F, Cheng CY. Microtubule-associated proteins (MAPs) in microtubule cytoskeletal dynamics and spermatogenesis. Histol Histopathol 2020; 36:249-265. [PMID: 33174615 DOI: 10.14670/hh-18-279] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The microtubule (MT) cytoskeleton in Sertoli cells, a crucial cellular structure in the seminiferous epithelium of adult mammalian testes that supports spermatogenesis, was studied morphologically decades ago. However, its biology, in particular the involving regulatory biomolecules and the underlying mechanism(s) in modulating MT dynamics, are only beginning to be revealed in recent years. This lack of studies in delineating the biology of MT cytoskeletal dynamics undermines other studies in the field, in particular the plausible therapeutic treatment and management of male infertility and fertility since studies have shown that the MT cytoskeleton is one of the prime targets of toxicants. Interestingly, much of the information regarding the function of actin-, MT- and intermediate filament-based cytoskeletons come from studies using toxicant models including some genetic models. During the past several years, there have been some advances in studying the biology of MT cytoskeleton in the testis, and many of these studies were based on the use of pharmaceutical/toxicant models. In this review, we summarize the results of these findings, illustrating the importance of toxicant/pharmaceutical models in unravelling the biology of MT dynamics, in particular the role of microtubule-associated proteins (MAPs), a family of regulatory proteins that modulate MT dynamics but also actin- and intermediate filament-based cytoskeletons. We also provide a timely hypothetical model which can serve as a guide to design functional experiments to study how the MT cytoskeleton is regulated during spermatogenesis through the use of toxicants and/or pharmaceutical agents.
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Affiliation(s)
- Lingling Wang
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China.,The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA.,Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Ming Yan
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Chris K C Wong
- Department of Biology, Croucher Institute for Environmental Sciences, Hong Kong Baptist University, Kowloon, Hong Kong, China
| | - Renshan Ge
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xiaolong Wu
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong, Jiangsu, China
| | - Fei Sun
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong, Jiangsu, China
| | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA.,The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China.
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76
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Kuo YW, Howard J. Cutting, Amplifying, and Aligning Microtubules with Severing Enzymes. Trends Cell Biol 2020; 31:50-61. [PMID: 33183955 PMCID: PMC7749064 DOI: 10.1016/j.tcb.2020.10.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 10/12/2020] [Accepted: 10/15/2020] [Indexed: 02/08/2023]
Abstract
Microtubule-severing enzymes - katanin, spastin, fidgetin - are related AAA-ATPases that cut microtubules into shorter filaments. These proteins, also called severases, are involved in a wide range of cellular processes including cell division, neuronal development, and tissue morphogenesis. Paradoxically, severases can amplify the microtubule cytoskeleton and not just destroy it. Recent work on spastin and katanin has partially resolved this paradox by showing that these enzymes are strong promoters of microtubule growth. Here, we review recent structural and biophysical advances in understanding the molecular mechanisms of severing and growth promotion that provide insight into how severing enzymes shape microtubule networks.
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Affiliation(s)
- Yin-Wei Kuo
- Department of Chemistry, Yale University, New Haven, CT 06511, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
| | - Jonathon Howard
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA.
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77
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Fourel G, Boscheron C. Tubulin mutations in neurodevelopmental disorders as a tool to decipher microtubule function. FEBS Lett 2020; 594:3409-3438. [PMID: 33064843 DOI: 10.1002/1873-3468.13958] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 09/28/2020] [Accepted: 10/05/2020] [Indexed: 01/08/2023]
Abstract
Malformations of cortical development (MCDs) are a group of severe brain malformations associated with intellectual disability and refractory childhood epilepsy. Human missense heterozygous mutations in the 9 α-tubulin and 10 β-tubulin isoforms forming the heterodimers that assemble into microtubules (MTs) were found to cause MCDs. However, how a single mutated residue in a given tubulin isoform can perturb the entire microtubule population in a neuronal cell remains a crucial question. Here, we examined 85 MCD-associated tubulin mutations occurring in TUBA1A, TUBB2, and TUBB3 and their location in a three-dimensional (3D) microtubule cylinder. Mutations hitting residues exposed on the outer microtubule surface are likely to alter microtubule association with partners, while alteration of intradimer contacts may impair dimer stability and straightness. Other types of mutations are predicted to alter interdimer and lateral contacts, which are responsible for microtubule cohesion, rigidity, and dynamics. MCD-associated tubulin mutations surprisingly fall into all categories, thus providing unexpected insights into how a single mutation may impair microtubule function and elicit dominant effects in neurons.
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78
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Dong Z, Li Y, Chen X, Lai X, Liu M. A comparative study of the expression patterns of Fign family members in zebrafish embryonic development. Comp Biochem Physiol B Biochem Mol Biol 2020; 251:110522. [PMID: 33069857 DOI: 10.1016/j.cbpb.2020.110522] [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: 07/31/2020] [Revised: 10/07/2020] [Accepted: 10/09/2020] [Indexed: 10/23/2022]
Abstract
During development, highly dynamic reconstruction of microtubules is involved in many cellular processes, including cell division, migration, morphological changes, and material transportation within cells. Microtubule severing proteins (MSPs), with the function of cutting microtubules into short parts, are important regulators in the reconstruction of microtubule arrays. Fidgetin (fign) and its family members fidgetin like 1 (fignl1) and fignl2 are MSPs, and knowledge on the expression patterns of fign family members will benefit our understanding of their primary roles in one specific stage during development. In this study, we compared the evolutionary relationships of fign family members and found that fignl2 is closer to fign than fignl1. We utilized the zebrafish model and in situ hybridization (ISH) to parallelly identify the expression features of fign family members. Our findings revealed that before 12 h post fertilization (hpf), the expression patterns of fign and fignl1 and fignl2 genes were similar, but differences arose thereafter. Fignl2 transcripts were present in more tissues and organs of zebrafish after 12 hpf and potentially exhibited more ubiquitous functions. This study is the first to assess systematic comparable data on the expression patterns of fign family members during development.
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Affiliation(s)
- Zhangji Dong
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong Jiangsu 226001, China
| | - Yuanyuan Li
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong Jiangsu 226001, China
| | - Xu Chen
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong Jiangsu 226001, China
| | - Xiaona Lai
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong Jiangsu 226001, China
| | - Mei Liu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong Jiangsu 226001, China.
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79
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Borys F, Joachimiak E, Krawczyk H, Fabczak H. Intrinsic and Extrinsic Factors Affecting Microtubule Dynamics in Normal and Cancer Cells. Molecules 2020; 25:E3705. [PMID: 32823874 PMCID: PMC7464520 DOI: 10.3390/molecules25163705] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 08/03/2020] [Accepted: 08/08/2020] [Indexed: 12/18/2022] Open
Abstract
Microtubules (MTs), highly dynamic structures composed of α- and β-tubulin heterodimers, are involved in cell movement and intracellular traffic and are essential for cell division. Within the cell, MTs are not uniform as they can be composed of different tubulin isotypes that are post-translationally modified and interact with different microtubule-associated proteins (MAPs). These diverse intrinsic factors influence the dynamics of MTs. Extrinsic factors such as microtubule-targeting agents (MTAs) can also affect MT dynamics. MTAs can be divided into two main categories: microtubule-stabilizing agents (MSAs) and microtubule-destabilizing agents (MDAs). Thus, the MT skeleton is an important target for anticancer therapy. This review discusses factors that determine the microtubule dynamics in normal and cancer cells and describes microtubule-MTA interactions, highlighting the importance of tubulin isoform diversity and post-translational modifications in MTA responses and the consequences of such a phenomenon, including drug resistance development.
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Affiliation(s)
- Filip Borys
- Laboratory of Cytoskeleton and Cilia Biology Nencki Institute of Experimental Biology of Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland;
- Department of Organic Chemistry, Faculty of Chemistry, Warsaw University of Technology, 3 Noakowskiego Street, 00-664 Warsaw, Poland;
| | - Ewa Joachimiak
- Laboratory of Cytoskeleton and Cilia Biology Nencki Institute of Experimental Biology of Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland;
| | - Hanna Krawczyk
- Department of Organic Chemistry, Faculty of Chemistry, Warsaw University of Technology, 3 Noakowskiego Street, 00-664 Warsaw, Poland;
| | - Hanna Fabczak
- Laboratory of Cytoskeleton and Cilia Biology Nencki Institute of Experimental Biology of Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland;
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80
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Long AF, Suresh P, Dumont S. Individual kinetochore-fibers locally dissipate force to maintain robust mammalian spindle structure. J Cell Biol 2020; 219:e201911090. [PMID: 32435797 PMCID: PMC7401803 DOI: 10.1083/jcb.201911090] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 03/16/2020] [Accepted: 04/27/2020] [Indexed: 01/16/2023] Open
Abstract
At cell division, the mammalian kinetochore binds many spindle microtubules that make up the kinetochore-fiber. To segregate chromosomes, the kinetochore-fiber must be dynamic and generate and respond to force. Yet, how it remodels under force remains poorly understood. Kinetochore-fibers cannot be reconstituted in vitro, and exerting controlled forces in vivo remains challenging. Here, we use microneedles to pull on mammalian kinetochore-fibers and probe how sustained force regulates their dynamics and structure. We show that force lengthens kinetochore-fibers by persistently favoring plus-end polymerization, not by increasing polymerization rate. We demonstrate that force suppresses depolymerization at both plus and minus ends, rather than sliding microtubules within the kinetochore-fiber. Finally, we observe that kinetochore-fibers break but do not detach from kinetochores or poles. Together, this work suggests an engineering principle for spindle structural homeostasis: different physical mechanisms of local force dissipation by the k-fiber limit force transmission to preserve robust spindle structure. These findings may inform how other dynamic, force-generating cellular machines achieve mechanical robustness.
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Affiliation(s)
- Alexandra F. Long
- Tetrad Graduate Program, University of California, San Francisco, San Francisco, CA
- Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, CA
- Department of Bioengineering and Therapeutic Science, University of California, San Francisco, San Francisco, CA
| | - Pooja Suresh
- Biophysics Graduate Program, University of California, San Francisco, San Francisco, CA
- Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, CA
- Department of Bioengineering and Therapeutic Science, University of California, San Francisco, San Francisco, CA
| | - Sophie Dumont
- Tetrad Graduate Program, University of California, San Francisco, San Francisco, CA
- Biophysics Graduate Program, University of California, San Francisco, San Francisco, CA
- Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, CA
- Department of Bioengineering and Therapeutic Science, University of California, San Francisco, San Francisco, CA
- Chan Zuckerberg Biohub, San Francisco, CA
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81
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Joly N, Beaumale E, Van Hove L, Martino L, Pintard L. Phosphorylation of the microtubule-severing AAA+ enzyme Katanin regulates C. elegans embryo development. J Cell Biol 2020; 219:e201912037. [PMID: 32412594 PMCID: PMC7265321 DOI: 10.1083/jcb.201912037] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 02/25/2020] [Accepted: 03/03/2020] [Indexed: 12/15/2022] Open
Abstract
The evolutionarily conserved microtubule (MT)-severing AAA-ATPase enzyme Katanin is emerging as a critical regulator of MT dynamics. In Caenorhabditis elegans, Katanin MT-severing activity is essential for meiotic spindle assembly but is toxic for the mitotic spindle. Here we analyzed Katanin dynamics in C. elegans and deciphered the role of Katanin phosphorylation in the regulation of its activity and stability. Katanin is abundant in oocytes, and its levels drop after meiosis, but unexpectedly, a significant fraction is present throughout embryogenesis, where it is dynamically recruited to the centrosomes and chromosomes during mitosis. We show that the minibrain kinase MBK-2, which is activated during meiosis, phosphorylates Katanin at multiple serines. We demonstrate unequivocally that Katanin phosphorylation at a single residue is necessary and sufficient to target Katanin for proteasomal degradation after meiosis, whereas phosphorylation at the other sites only inhibits Katanin ATPase activity stimulated by MTs. Our findings suggest that cycles of phosphorylation and dephosphorylation fine-tune Katanin level and activity to deliver the appropriate MT-severing activity during development.
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Affiliation(s)
- Nicolas Joly
- Programme Equipes Labellisées Ligue contre le Cancer – Team “Cell Cycle and Development,” Centre National de la Recherche Scientifique – UMR7592, Institut Jacques Monod/University of Paris, Paris, France
| | | | | | | | - Lionel Pintard
- Programme Equipes Labellisées Ligue contre le Cancer – Team “Cell Cycle and Development,” Centre National de la Recherche Scientifique – UMR7592, Institut Jacques Monod/University of Paris, Paris, France
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82
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Lüders J. Nucleating microtubules in neurons: Challenges and solutions. Dev Neurobiol 2020; 81:273-283. [PMID: 32324945 DOI: 10.1002/dneu.22751] [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: 11/11/2019] [Revised: 01/08/2020] [Accepted: 04/20/2020] [Indexed: 11/08/2022]
Abstract
The highly polarized morphology of neurons is crucial for their function and involves formation of two distinct types of cellular extensions, the axonal and dendritic compartments. An important effector required for the morphogenesis and maintenance and thus the identity of axons and dendrites is the microtubule cytoskeleton. Microtubules in axons and dendrites are arranged with distinct polarities, to allow motor-dependent, compartment-specific sorting of cargo. Despite the importance of the microtubule cytoskeleton in neurons, the molecular mechanisms that generate the intricate compartment-specific microtubule configurations remain largely obscure. Work in other cell types has identified microtubule nucleation, the de novo formation of microtubules, and its spatio-temporal regulation as essential for the proper organization of the microtubule cytoskeleton. Whereas regulation of microtubule nucleation usually involves microtubule organizing centers such as the centrosome, neurons seem to rely largely on decentralized nucleation mechanisms. In this review, I will discuss recent advances in deciphering nucleation mechanisms in neurons, how they contribute to the arrangement of microtubules with specific polarities, and how this affects neuron morphogenesis. While this work has shed some light on these important processes, we are far from a comprehensive understanding. Thus, to provide a coherent model, my discussion will include both well-established mechanisms and mechanisms with more limited supporting data. Finally, I will also highlight important outstanding questions for future investigation.
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Affiliation(s)
- Jens Lüders
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
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83
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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: 19] [Impact Index Per Article: 4.8] [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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84
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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: 385] [Impact Index Per Article: 96.3] [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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85
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Dynamic microtubules at the synapse. Curr Opin Neurobiol 2020; 63:9-14. [PMID: 32062144 DOI: 10.1016/j.conb.2020.01.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 01/07/2020] [Accepted: 01/08/2020] [Indexed: 01/03/2023]
Abstract
Microtubules (MTs) are a fundamental cytoskeletal component that give neurons structure and are the primary polymer system for long distance transport of cargo throughout the cytoplasm. Although neurons are highly polarized and their structure is often maintained throughout the life of an organism, MTs can remain dynamic in axons and dendrites, undergoing bouts of polymerization and depolymerization, referred to as dynamic instability. Furthermore, MTs can be nucleated outside of the centrosome or MT organizing center (MTOC) that is located in the cell body, allowing dynamic formation and branching of MT polymers throughout the neuron. Together, these recent findings point to a much more dynamic landscape of microtubules in developing and mature neurons than was previously appreciated. Here we will focus on recent studies that show MT dynamics are playing a role at the synapse, both post-synaptically in dendrites and pre-synaptically in axons.
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86
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Hagen KD, McInally SG, Hilton ND, Dawson SC. Microtubule organelles in Giardia. ADVANCES IN PARASITOLOGY 2020; 107:25-96. [PMID: 32122531 DOI: 10.1016/bs.apar.2019.11.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Giardia lamblia is a widespread parasitic protist with a complex MT cytoskeleton that is critical for motility, attachment, mitosis and cell division, and transitions between its two life cycle stages-the infectious cyst and flagellated trophozoite. Giardia trophozoites have both highly dynamic and highly stable MT organelles, including the ventral disc, eight flagella, the median body and the funis. The ventral disc, an elaborate MT organelle, is essential for the parasite's attachment to the intestinal villi to avoid peristalsis. Giardia's four flagellar pairs enable swimming motility and may also promote attachment. They are maintained at different equilibrium lengths and are distinguished by their long cytoplasmic regions and novel extra-axonemal structures. The functions of the median body and funis, MT organelles unique to Giardia, remain less understood. In addition to conserved MT-associated proteins, the genome is enriched in ankyrins, NEKs, and novel hypothetical proteins that also associate with the MT cytoskeleton. High-resolution ultrastructural imaging and a current inventory of more than 300 proteins associated with Giardia's MT cytoskeleton lay the groundwork for future mechanistic analyses of parasite attachment to the host, motility, cell division, and encystation/excystation. Giardia's unique MT organelles exemplify the capacity of MT polymers to generate intricate structures that are diverse in both form and function. Thus, beyond its relevance to pathogenesis, the study of Giardia's MT cytoskeleton informs basic cytoskeletal biology and cellular evolution. With the availability of new molecular genetic tools to disrupt gene function, we anticipate a new era of cytoskeletal discovery in Giardia.
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Affiliation(s)
- Kari D Hagen
- Department of Microbiology and Molecular Genetics, UC Davis, Davis, CA, United States
| | - Shane G McInally
- Department of Microbiology and Molecular Genetics, UC Davis, Davis, CA, United States
| | - Nicholas D Hilton
- Department of Microbiology and Molecular Genetics, UC Davis, Davis, CA, United States
| | - Scott C Dawson
- Department of Microbiology and Molecular Genetics, UC Davis, Davis, CA, United States.
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87
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Joachimiak E, Waclawek E, Niziolek M, Osinka A, Fabczak H, Gaertig J, Wloga D. The LisH Domain-Containing N-Terminal Fragment is Important for the Localization, Dimerization, and Stability of Katnal2 in Tetrahymena. Cells 2020; 9:cells9020292. [PMID: 31991798 PMCID: PMC7072489 DOI: 10.3390/cells9020292] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 01/14/2020] [Accepted: 01/22/2020] [Indexed: 12/12/2022] Open
Abstract
Katanin-like 2 protein (Katnal2) orthologs have a tripartite domain organization. Two highly conserved regions, an N-terminal LisH (Lis-homology) domain and a C-terminal AAA catalytic domain, are separated by a less conserved linker. The AAA domain of Katnal2 shares the highest amino acid sequence homology with the AAA domain of the canonical katanin p60. Katnal2 orthologs are present in a wide range of eukaryotes, from protists to humans. In the ciliate Tetrahymena thermophila, a Katnal2 ortholog, Kat2, co-localizes with the microtubular structures, including basal bodies and ciliary outer doublets, and this co-localization is sensitive to levels of microtubule glutamylation. The functional analysis of Kat2 domains suggests that an N-terminal fragment containing a LisH domain plays a role in the subcellular localization, dimerization, and stability of Kat2.
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Affiliation(s)
- Ewa Joachimiak
- Laboratory of Cytoskeleton and Cilia Biology, Nencki Institute of Experimental Biology PAS, 3 Pasteur, 02-093 Warsaw, Poland; (E.J.); (E.W.); (M.N.); (A.O.); (H.F.)
| | - Ewa Waclawek
- Laboratory of Cytoskeleton and Cilia Biology, Nencki Institute of Experimental Biology PAS, 3 Pasteur, 02-093 Warsaw, Poland; (E.J.); (E.W.); (M.N.); (A.O.); (H.F.)
| | - Michal Niziolek
- Laboratory of Cytoskeleton and Cilia Biology, Nencki Institute of Experimental Biology PAS, 3 Pasteur, 02-093 Warsaw, Poland; (E.J.); (E.W.); (M.N.); (A.O.); (H.F.)
| | - Anna Osinka
- Laboratory of Cytoskeleton and Cilia Biology, Nencki Institute of Experimental Biology PAS, 3 Pasteur, 02-093 Warsaw, Poland; (E.J.); (E.W.); (M.N.); (A.O.); (H.F.)
| | - Hanna Fabczak
- Laboratory of Cytoskeleton and Cilia Biology, Nencki Institute of Experimental Biology PAS, 3 Pasteur, 02-093 Warsaw, Poland; (E.J.); (E.W.); (M.N.); (A.O.); (H.F.)
| | - Jacek Gaertig
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA;
| | - Dorota Wloga
- Laboratory of Cytoskeleton and Cilia Biology, Nencki Institute of Experimental Biology PAS, 3 Pasteur, 02-093 Warsaw, Poland; (E.J.); (E.W.); (M.N.); (A.O.); (H.F.)
- Correspondence: ; Tel.: +48-(22)-5892338
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RhoA-GTPase Modulates Neurite Outgrowth by Regulating the Expression of Spastin and p60-Katanin. Cells 2020; 9:cells9010230. [PMID: 31963385 PMCID: PMC7016723 DOI: 10.3390/cells9010230] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 01/10/2020] [Accepted: 01/14/2020] [Indexed: 12/17/2022] Open
Abstract
RhoA-GTPase (RhoA) is widely regarded as a key molecular switch to inhibit neurite outgrowth by rigidifying the actin cytoskeleton. However, during neurite outgrowth, whether and how microtubule dynamics are regulated by RhoA remains to be elucidated. Herein, CT04 and Y27632 were used to inactivate RhoA and its downstream effector Rho-associated coiled coil-forming kinase (ROCK), while the RhoAQ63L lentiviral vector was utilized to overexpress the constitutively activated RhoA in dorsal root ganglion (DRG) neurons or neuronal differentiated PC12 cells. The current data illustrate that the RhoA signaling pathway negatively modulates neurite outgrowth and elevates the expression of Glu-tubulin (a marker for a stabilized microtubule). Meanwhile, the microtubule-severing proteins spastin and p60-katanin were downregulated by the RhoA signaling pathway. When spastin and p60-katanin were knocked down, the effects of RhoA inhibition on neurite outgrowth were significantly reversed. Taken together, this study demonstrates that the RhoA pathway-mediated inhibition of neurite outgrowth is not only related to the modulation of microfilament dynamics but is also attributable to the regulation of the expression of spastin and p60-katanin and thus influences microtubule dynamics.
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89
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Zehr EA, Szyk A, Szczesna E, Roll-Mecak A. Katanin Grips the β-Tubulin Tail through an Electropositive Double Spiral to Sever Microtubules. Dev Cell 2020; 52:118-131.e6. [PMID: 31735665 PMCID: PMC7060837 DOI: 10.1016/j.devcel.2019.10.010] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 09/11/2019] [Accepted: 10/14/2019] [Indexed: 11/16/2022]
Abstract
The AAA ATPase katanin severs microtubules. It is critical in cell division, centriole biogenesis, and neuronal morphogenesis. Its mutation causes microcephaly. The microtubule templates katanin hexamerization and activates its ATPase. The structural basis for these activities and how they lead to severing is unknown. Here, we show that β-tubulin tails are necessary and sufficient for severing. Cryoelectron microscopy (cryo-EM) structures reveal the essential tubulin tail glutamates gripped by a double spiral of electropositive loops lining the katanin central pore. Each spiral couples allosterically to the ATPase and binds alternating, successive substrate residues, with consecutive residues coordinated by adjacent protomers. This tightly couples tail binding, hexamerization, and ATPase activation. Hexamer structures in different states suggest an ATPase-driven, ratchet-like translocation of the tubulin tail through the pore. A disordered region outside the AAA core anchors katanin to the microtubule while the AAA motor exerts the forces that extract tubulin dimers and sever the microtubule.
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Affiliation(s)
- Elena A Zehr
- Cell Biology and Biophysics Unit, Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20982, USA
| | - Agnieszka Szyk
- Cell Biology and Biophysics Unit, Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20982, USA
| | - Ewa Szczesna
- Cell Biology and Biophysics Unit, Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20982, USA
| | - Antonina Roll-Mecak
- Cell Biology and Biophysics Unit, Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20982, USA; Biochemistry and Biophysics Center, National Heart Lung and Blood Institute, Bethesda, MD 20892, USA.
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90
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Zhou B, Wang J, Gao J, Xie J, Chen Y. Fidgetin as a potential prognostic biomarker for hepatocellular carcinoma. Int J Med Sci 2020; 17:2888-2894. [PMID: 33162817 PMCID: PMC7645349 DOI: 10.7150/ijms.49913] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 09/27/2020] [Indexed: 12/04/2022] Open
Abstract
Background: Fidgetin (FIGN), a conserved ATP-dependent enzyme, is regarded as a hepatocellular carcinoma (HCC) risk gene, but the prognostic implication of FIGN in HCC remains obscure. In this study, we investigate the expression of FIGN in HCC and to evaluate its prognostic value. Methods: A total of 216 patients with HCC who experienced hepatectomy were recruited in this study. The expression of FIGN in HCC samples was evaluated by quantitative real-time PCR, immunohistochemistry and immunoblotting analysis. And Cox regression model was used to evaluate the prognostic value of all covariates. Results: Of the 216 HCC patients, 67 (31.0%) had tumors with high FIGN expression and 149 (69.0%) had tumors with low FIGN expression. FIGN expression was positively correlated with TNM stage (P = 0.039), tumor with incomplete capsule (P = 0.036), microvascular invasion (P = 0.023), and portal vein tumor thrombus (P = 0.003). High expression of FIGN indicated shorter overall survival (OS) (hazard ratio: 4.569, P = 0.036) and disease-free survival (DFS) (hazard ratio: 6.487, P = 0.001). Conclusion: Our results indicate that high Fidgetin expression is associated with tumor progression and suggest a worse prognosis in HCC. Fidgetin might serve as a potential target for therapy.
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Affiliation(s)
- Bin Zhou
- Department of Hepatobiliary Surgery, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang, China
| | - Jisheng Wang
- Department of Hepatobiliary Surgery, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang, China
| | - Jing Gao
- Department of Hepatobiliary Surgery, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang, China
| | - Junqing Xie
- Department of Hepatobiliary Surgery, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang, China
| | - Yiming Chen
- Department of Hepatobiliary Surgery, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang, China
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91
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Han H, Schubert HL, McCullough J, Monroe N, Purdy MD, Yeager M, Sundquist WI, Hill CP. Structure of spastin bound to a glutamate-rich peptide implies a hand-over-hand mechanism of substrate translocation. J Biol Chem 2019; 295:435-443. [PMID: 31767681 DOI: 10.1074/jbc.ac119.009890] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 11/11/2019] [Indexed: 11/06/2022] Open
Abstract
Many members of the AAA+ ATPase family function as hexamers that unfold their protein substrates. These AAA unfoldases include spastin, which plays a critical role in the architecture of eukaryotic cells by driving the remodeling and severing of microtubules, which are cytoskeletal polymers of tubulin subunits. Here, we demonstrate that a human spastin binds weakly to unmodified peptides from the C-terminal segment of human tubulin α1A/B. A peptide comprising alternating glutamate and tyrosine residues binds more tightly, which is consistent with the known importance of glutamylation for spastin microtubule severing activity. A cryo-EM structure of the spastin-peptide complex at 4.2 Å resolution revealed an asymmetric hexamer in which five spastin subunits adopt a helical, spiral staircase configuration that binds the peptide within the central pore, whereas the sixth subunit of the hexamer is displaced from the peptide/substrate, as if transitioning from one end of the helix to the other. This configuration differs from a recently published structure of spastin from Drosophila melanogaster, which forms a six-subunit spiral without a transitioning subunit. Our structure resembles other recently reported AAA unfoldases, including the meiotic clade relative Vps4, and supports a model in which spastin utilizes a hand-over-hand mechanism of tubulin translocation and microtubule remodeling.
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Affiliation(s)
- Han Han
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah 84112
| | - Heidi L Schubert
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah 84112
| | - John McCullough
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah 84112
| | - Nicole Monroe
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah 84112
| | - Michael D Purdy
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, Virginia 22908
| | - Mark Yeager
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, Virginia 22908; Department of Medicine, Division of Cardiovascular Medicine, University of Virginia School of Medicine, Charlottesville, Virginia 22908; Center for Membrane and Cell Physiology, University of Virginia School of Medicine, Charlottesville, Virginia 22908; Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, Virginia 22908
| | - Wesley I Sundquist
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah 84112.
| | - Christopher P Hill
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah 84112.
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92
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Sasaki T, Tsutsumi M, Otomo K, Murata T, Yagi N, Nakamura M, Nemoto T, Hasebe M, Oda Y. A Novel Katanin-Tethering Machinery Accelerates Cytokinesis. Curr Biol 2019; 29:4060-4070.e3. [PMID: 31735673 DOI: 10.1016/j.cub.2019.09.049] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 08/15/2019] [Accepted: 09/19/2019] [Indexed: 12/26/2022]
Abstract
Cytokinesis is fundamental for cell proliferation [1, 2]. In plants, a bipolar short-microtubule array forms the phragmoplast, which mediates vesicle transport to the midzone and guides the formation of cell walls that separate the mother cell into two daughter cells [2]. The phragmoplast centrifugally expands toward the cell cortex to guide cell-plate formation at the cortical division site [3, 4]. Several proteins in the phragmoplast midzone facilitate the anti-parallel bundling of microtubules and vesicle accumulation [5]. However, the mechanisms by which short microtubules are maintained during phragmoplast development, in particular, the behavior of microtubules at the distal zone of phragmoplasts, are poorly understood. Here, we show that a plant-specific protein, CORTICAL MICROTUBULE DISORDERING 4 (CORD4), tethers the conserved microtubule-severing protein katanin to facilitate formation of the short-microtubule array in phragmoplasts. CORD4 was specifically expressed during mitosis and localized to preprophase bands and phragmoplast microtubules. Custom-made two-photon spinning disk confocal microscopy revealed that CORD4 rapidly localized to microtubules in the distal phragmoplast zone during phragmoplast assembly at late anaphase and persisted throughout phragmoplast expansion. Loss of CORD4 caused abnormally long and oblique phragmoplast microtubules and slow expansion of phragmoplasts. The p60 katanin subunit, KTN1, localized to the distal phragmoplast zone in a CORD4-dependent manner. These results suggest that CORD4 tethers KTN1 at phragmoplasts to modulate microtubule length, thereby accelerating phragmoplast growth. This reveals the presence of a distinct machinery to accelerate cytokinesis by regulating the action of katanin.
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Affiliation(s)
- Takema Sasaki
- Department of Gene Function and Phenomics, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
| | - Motosuke Tsutsumi
- Nikon Imaging Center, Research Institute for Electronic Science, Hokkaido University, Sapporo, Hokkaido 001-0020, Japan
| | - Kohei Otomo
- Nikon Imaging Center, Research Institute for Electronic Science, Hokkaido University, Sapporo, Hokkaido 001-0020, Japan; Graduate School of Information Science and Technology, Hokkaido University, Sapporo, Hokkaido 060-0814, Japan
| | - Takashi Murata
- Division of Evolutionary Biology, National Institute for Basic Biology, Okazaki, Aichi 444-8585, Japan; Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies, SOKENDAI, Okazaki, Aichi 444-8585, Japan
| | - Noriyoshi Yagi
- Institute of transformative Bio-Molecules (WPI-ITbM), Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Masayoshi Nakamura
- Institute of transformative Bio-Molecules (WPI-ITbM), Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Tomomi Nemoto
- Nikon Imaging Center, Research Institute for Electronic Science, Hokkaido University, Sapporo, Hokkaido 001-0020, Japan; Graduate School of Information Science and Technology, Hokkaido University, Sapporo, Hokkaido 060-0814, Japan
| | - Mitsuyasu Hasebe
- Division of Evolutionary Biology, National Institute for Basic Biology, Okazaki, Aichi 444-8585, Japan; Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies, SOKENDAI, Okazaki, Aichi 444-8585, Japan
| | - Yoshihisa Oda
- Department of Gene Function and Phenomics, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan; Department of Genetics, School of Life Science, The Graduate University for Advanced Studies, SOKENDAI, Mishima, Shizuoka 411-8540, Japan.
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93
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Qu Y, Hahn I, Lees M, Parkin J, Voelzmann A, Dorey K, Rathbone A, Friel CT, Allan VJ, Okenve-Ramos P, Sanchez-Soriano N, Prokop A. Efa6 protects axons and regulates their growth and branching by inhibiting microtubule polymerisation at the cortex. eLife 2019; 8:e50319. [PMID: 31718774 PMCID: PMC6884004 DOI: 10.7554/elife.50319] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 11/06/2019] [Indexed: 12/12/2022] Open
Abstract
Cortical collapse factors affect microtubule (MT) dynamics at the plasma membrane. They play important roles in neurons, as suggested by inhibition of axon growth and regeneration through the ARF activator Efa6 in C. elegans, and by neurodevelopmental disorders linked to the mammalian kinesin Kif21A. How cortical collapse factors influence axon growth is little understood. Here we studied them, focussing on the function of Drosophila Efa6 in experimentally and genetically amenable fly neurons. First, we show that Drosophila Efa6 can inhibit MTs directly without interacting molecules via an N-terminal 18 amino acid motif (MT elimination domain/MTED) that binds tubulin and inhibits microtubule growth in vitro and cells. If N-terminal MTED-containing fragments are in the cytoplasm they abolish entire microtubule networks of mouse fibroblasts and whole axons of fly neurons. Full-length Efa6 is membrane-attached, hence primarily blocks MTs in the periphery of fibroblasts, and explorative MTs that have left axonal bundles in neurons. Accordingly, loss of Efa6 causes an increase of explorative MTs: in growth cones they enhance axon growth, in axon shafts they cause excessive branching, as well as atrophy through perturbations of MT bundles. Efa6 over-expression causes the opposite phenotypes. Taken together, our work conceptually links molecular and sub-cellular functions of cortical collapse factors to axon growth regulation and reveals new roles in axon branching and in the prevention of axonal atrophy. Furthermore, the MTED delivers a promising tool that can be used to inhibit MTs in a compartmentalised fashion when fusing it to specifically localising protein domains.
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Affiliation(s)
- Yue Qu
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biological SciencesThe University of ManchesterManchesterUnited Kingdom
| | - Ines Hahn
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biological SciencesThe University of ManchesterManchesterUnited Kingdom
| | - Meredith Lees
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biological SciencesThe University of ManchesterManchesterUnited Kingdom
| | - Jill Parkin
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biological SciencesThe University of ManchesterManchesterUnited Kingdom
| | - André Voelzmann
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biological SciencesThe University of ManchesterManchesterUnited Kingdom
| | - Karel Dorey
- Faculty of Biology, Medicine and Health, School of Medical SciencesThe University of ManchesterManchesterUnited Kingdom
| | - Alex Rathbone
- School of Life Sciences, Faculty of Medicine and Health SciencesThe University of NottinghamNottinghamUnited Kingdom
| | - Claire T Friel
- School of Life Sciences, Faculty of Medicine and Health SciencesThe University of NottinghamNottinghamUnited Kingdom
| | - Victoria J Allan
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biological SciencesThe University of ManchesterManchesterUnited Kingdom
| | - Pilar Okenve-Ramos
- Department of Cellular and Molecular Physiology,Institute of Translational MedicineUniversity of LiverpoolLiverpoolUnited Kingdom
| | - Natalia Sanchez-Soriano
- Department of Cellular and Molecular Physiology,Institute of Translational MedicineUniversity of LiverpoolLiverpoolUnited Kingdom
| | - Andreas Prokop
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biological SciencesThe University of ManchesterManchesterUnited Kingdom
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94
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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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95
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Peterman E, Prekeris R. The postmitotic midbody: Regulating polarity, stemness, and proliferation. J Cell Biol 2019; 218:3903-3911. [PMID: 31690620 PMCID: PMC6891101 DOI: 10.1083/jcb.201906148] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 09/17/2019] [Accepted: 10/18/2019] [Indexed: 12/15/2022] Open
Abstract
Peterman and Prekeris review abscission and discuss the diverse roles for the postmitotic midbody in regulating polarity, tumorigenesis, and stemness. Abscission, the final stage of cell division, requires well-orchestrated changes in endocytic trafficking, microtubule severing, actin clearance, and the physical sealing of the daughter cell membranes. These processes are highly regulated, and any missteps in localized membrane and cytoskeleton dynamics often lead to a delay or a failure in cell division. The midbody, a microtubule-rich structure that forms during cytokinesis, is a key regulator of abscission and appears to function as a signaling platform coordinating cytoskeleton and endosomal dynamics during the terminal stages of cell division. It was long thought that immediately following abscission and the conclusion of cell division, the midbody is either released or rapidly degraded by one of the daughter cells. Recently, the midbody has gained prominence for exerting postmitotic functions. In this review, we detail the role of the midbody in orchestrating abscission, as well as discuss the relatively new field of postabscission midbody biology, particularly focusing on how it may act to regulate cell polarity and its potential to regulate cell tumorigenicity or stemness.
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Affiliation(s)
- Eric Peterman
- Department of Cell and Developmental Biology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Rytis Prekeris
- Department of Cell and Developmental Biology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO
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96
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Yoshida S, Yoshida K. Multiple functions of DYRK2 in cancer and tissue development. FEBS Lett 2019; 593:2953-2965. [PMID: 31505048 DOI: 10.1002/1873-3468.13601] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 08/27/2019] [Accepted: 09/02/2019] [Indexed: 01/09/2023]
Abstract
Dual-specificity tyrosine-regulated kinases (DYRKs) are evolutionarily conserved from yeast to mammals. Accumulating studies have revealed that DYRKs have important roles in regulation of the cell cycle and survival. DYRK2, a member of the class II DYRK family protein, is a key regulator of p53, and phosphorylates it at Ser46 to induce apoptosis in response to DNA damage. Moreover, recent studies have uncovered that DYRK2 regulates G1/S transition, epithelial-mesenchymal-transition, and stemness in human cancer cells. DYRK2 also appears to have roles in tissue development in lower eukaryotes. Thus, the elucidation of mechanisms for DYRK2 during mammalian tissue development will promote the understanding of cell differentiation, tissue homeostasis, and congenital diseases as well as cancer. In this review, we discuss the roles of DYRK2 in tumor cells. Moreover, we focus on DYRK2-dependent developmental mechanisms in several species including fly (Drosophila), worm (Caenorhabditis elegans), zebrafish (Danio rerio), and mammals.
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Affiliation(s)
- Saishu Yoshida
- Department of Biochemistry, The Jikei University School of Medicine, Tokyo, Japan
| | - Kiyotsugu Yoshida
- Department of Biochemistry, The Jikei University School of Medicine, Tokyo, Japan
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97
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Kuo YW, Trottier O, Howard J. Predicted Effects of Severing Enzymes on the Length Distribution and Total Mass of Microtubules. Biophys J 2019; 117:2066-2078. [PMID: 31708162 DOI: 10.1016/j.bpj.2019.10.027] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 10/17/2019] [Accepted: 10/22/2019] [Indexed: 01/12/2023] Open
Abstract
Microtubules are dynamic cytoskeletal polymers whose growth and shrinkage are highly regulated as eukaryotic cells change shape, move, and divide. One family of microtubule regulators includes the ATP-hydrolyzing enzymes spastin, katanin, and fidgetin, which sever microtubule polymers into shorter fragments. Paradoxically, severases can increase microtubule number and mass in cells. Recent work with purified spastin and katanin accounts for this phenotype by showing that, in addition to severing, these enzymes modulate microtubule dynamics by accelerating the conversion of microtubules from their shrinking to their growing states and thereby promoting their regrowth. This leads to the observed exponential increase in microtubule mass. Spastin also influences the steady-state distribution of microtubule lengths, changing it from an exponential, as predicted by models of microtubule dynamic instability, to a peaked distribution. This effect of severing and regrowth by spastin on the microtubule length distribution has not been explained theoretically. To solve this problem, we formulated and solved a master equation for the time evolution of microtubule lengths in the presence of severing and microtubule dynamic instability. We then obtained numerical solutions to the steady-state length distribution and showed that the rate of severing and the speed of microtubule growth are the dominant parameters determining the steady-state length distribution. Furthermore, we found that the amplification rate is predicted to increase with severing, which is, to our knowledge, a new result. Our results establish a theoretical basis for how severing and dynamics together can serve to nucleate new microtubules, constituting a versatile mechanism to regulate microtubule length and mass.
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Affiliation(s)
- Yin-Wei Kuo
- Department of Chemistry, Yale University, New Haven, Connecticut; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut
| | - Olivier Trottier
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut; Department of Physics, Yale University, New Haven, Connecticut
| | - Jonathon Howard
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut.
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98
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Drechsler H, Xu Y, Geyer VF, Zhang Y, Diez S. Multivalent electrostatic microtubule interactions of synthetic peptides are sufficient to mimic advanced MAP-like behavior. Mol Biol Cell 2019; 30:2953-2968. [PMID: 31599700 PMCID: PMC6857568 DOI: 10.1091/mbc.e19-05-0247] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Microtubule-associated proteins (MAPs) are a functionally highly diverse class of proteins that help to adjust the shape and function of the microtubule cytoskeleton in space and time. For this purpose, MAPs structurally support microtubules, modulate their dynamic instability, or regulate the activity of associated molecular motors. The microtubule-binding domains of MAPs are structurally divergent, but often depend on electrostatic interactions with the negatively charged surface of the microtubule. This suggests that the surface exposure of positive charges rather than a certain structural fold is sufficient for a protein to associate with microtubules. Consistently, positively charged artificial objects have been shown to associate with microtubules and to diffuse along their lattice. Natural MAPs, however, show a more sophisticated functionality beyond lattice-diffusion. Here, we asked whether basic electrostatic interactions are sufficient to also support advanced MAP functionality. To test this hypothesis, we studied simple positively charged peptide sequences for the occurrence of typical MAP-like behavior. We found that a multivalent peptide construct featuring four lysine-alanine heptarepeats (starPEG-(KA7)4)-but not its monovalent KA7-subunits-show advanced, biologically relevant MAP-like behavior: starPEG-(KA7)4 binds microtubules in the low nanomolar range, diffuses along their lattice with the ability to switch between intersecting microtubules, and tracks depolymerizing microtubule ends. Further, starPEG-(KA7)4 promotes microtubule nucleation and growth, mediates depolymerization coupled pulling at plus ends, and bundles microtubules without significantly interfering with other proteins on the microtubule lattice (as exemplified by the motor kinesin-1). Our results show that positive charges and multivalency are sufficient to mimic advanced MAP-like behavior.
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Affiliation(s)
- Hauke Drechsler
- B CUBE-Center for Molecular Bioengineering, Technische -Universität -Dresden, Dresden 01307, Germany
| | - Yong Xu
- B CUBE-Center for Molecular Bioengineering, Technische -Universität -Dresden, Dresden 01307, Germany
| | - Veikko F Geyer
- B CUBE-Center for Molecular Bioengineering, Technische -Universität -Dresden, Dresden 01307, Germany
| | - Yixin Zhang
- B CUBE-Center for Molecular Bioengineering, Technische -Universität -Dresden, Dresden 01307, Germany
| | - Stefan Diez
- B CUBE-Center for Molecular Bioengineering, Technische -Universität -Dresden, Dresden 01307, Germany.,Cluster of Excellence Physics of Life, Technische -Universität -Dresden, Dresden 01307, Germany.,Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
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Burute M, Kapitein LC. Cellular Logistics: Unraveling the Interplay Between Microtubule Organization and Intracellular Transport. Annu Rev Cell Dev Biol 2019; 35:29-54. [DOI: 10.1146/annurev-cellbio-100818-125149] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Microtubules are core components of the cytoskeleton and serve as tracks for motor protein–based intracellular transport. Microtubule networks are highly diverse across different cell types and are believed to adapt to cell type–specific transport demands. Here we review how the spatial organization of different subsets of microtubules into higher-order networks determines the traffic rules for motor-based transport in different animal cell types. We describe the interplay between microtubule network organization and motor-based transport within epithelial cells, oocytes, neurons, cilia, and the spindle apparatus.
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Affiliation(s)
- Mithila Burute
- Department of Biology, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Lukas C. Kapitein
- Department of Biology, Utrecht University, 3584 CH Utrecht, The Netherlands
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100
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Bodakuntla S, Jijumon AS, Villablanca C, Gonzalez-Billault C, Janke C. Microtubule-Associated Proteins: Structuring the Cytoskeleton. Trends Cell Biol 2019; 29:804-819. [PMID: 31416684 DOI: 10.1016/j.tcb.2019.07.004] [Citation(s) in RCA: 165] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 07/11/2019] [Accepted: 07/12/2019] [Indexed: 11/27/2022]
Abstract
Microtubule-associated proteins (MAPs) were initially discovered as proteins that bind to and stabilize microtubules. Today, an ever-growing number of MAPs reveals a more complex picture of these proteins as organizers of the microtubule cytoskeleton that have a large variety of functions. MAPs enable microtubules to participate in a plethora of cellular processes such as the assembly of mitotic and meiotic spindles, neuronal development, and the formation of the ciliary axoneme. Although some subgroups of MAPs have been exhaustively characterized, a strikingly large number of MAPs remain barely characterized other than their interactions with microtubules. We provide a comprehensive view on the currently known MAPs in mammals. We discuss their molecular mechanisms and functions, as well as their physiological role and links to pathologies.
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Affiliation(s)
- Satish Bodakuntla
- Institut Curie, Paris Sciences et Lettres (PSL) Research University, Centre National de la Recherche Scientifique (CNRS) Unité Mixte de Recherche (UMR) 3348, F-91405 Orsay, France; Université Paris Sud, Université Paris-Saclay, CNRS UMR 3348, F-91405 Orsay, France
| | - A S Jijumon
- Institut Curie, Paris Sciences et Lettres (PSL) Research University, Centre National de la Recherche Scientifique (CNRS) Unité Mixte de Recherche (UMR) 3348, F-91405 Orsay, France; Université Paris Sud, Université Paris-Saclay, CNRS UMR 3348, F-91405 Orsay, France
| | - Cristopher Villablanca
- Center for Geroscience, Brain Health, and Metabolism (GERO), Santiago, Chile; Department of Biology, Faculty of Sciences, University of Chile, Santiago, Chile
| | - Christian Gonzalez-Billault
- Center for Geroscience, Brain Health, and Metabolism (GERO), Santiago, Chile; Department of Biology, Faculty of Sciences, University of Chile, Santiago, Chile.
| | - Carsten Janke
- Institut Curie, Paris Sciences et Lettres (PSL) Research University, Centre National de la Recherche Scientifique (CNRS) Unité Mixte de Recherche (UMR) 3348, F-91405 Orsay, France; Université Paris Sud, Université Paris-Saclay, CNRS UMR 3348, F-91405 Orsay, France.
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