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Kim Y, Lee HK, Park KY, Ismail T, Lee H, Ryu HY, Cho DH, Kwon TK, Park TJ, Kwon T, Lee HS. Actin depolymerizing factor destrin governs cell migration in neural development during Xenopus embryogenesis. Mol Cells 2024; 47:100076. [PMID: 38825188 PMCID: PMC11227013 DOI: 10.1016/j.mocell.2024.100076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 05/13/2024] [Accepted: 05/27/2024] [Indexed: 06/04/2024] Open
Abstract
The actin-based cytoskeleton is considered a fundamental driving force for cell differentiation and development. Destrin (Dstn), a member of the actin-depolymerizing factor family, regulates actin dynamics by treadmilling actin filaments and increasing globular actin pools. However, the specific developmental roles of dstn have yet to be fully elucidated. Here, we investigated the physiological functions of dstn during early embryonic development using Xenopus laevis as an experimental model organism. dstn is expressed in anterior neural tissue and neural plate during Xenopus embryogenesis. Depleting dstn promoted morphants with short body axes and small heads. Moreover, dstn inhibition extended the neural plate region, impairing cell migration and distribution during neurulation. In addition to the neural plate, dstn knockdown perturbed neural crest cell migration. Our data suggest new insights for understanding the roles of actin dynamics in embryonic neural development, simultaneously presenting a new challenge for studying the complex networks governing cell migration involving actin dynamics.
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Affiliation(s)
- Youni Kim
- KNU G-LAMP Project Group, KNU Institute of Basic Sciences, BK21 FOUR KNU Creative BioResearch Group, School of Life Sciences, College of Natural Sciences, Kyungpook National University, Daegu 41566, Korea
| | - Hyun-Kyung Lee
- KNU G-LAMP Project Group, KNU Institute of Basic Sciences, BK21 FOUR KNU Creative BioResearch Group, School of Life Sciences, College of Natural Sciences, Kyungpook National University, Daegu 41566, Korea
| | - Kyeong-Yeon Park
- KNU G-LAMP Project Group, KNU Institute of Basic Sciences, BK21 FOUR KNU Creative BioResearch Group, School of Life Sciences, College of Natural Sciences, Kyungpook National University, Daegu 41566, Korea
| | - Tayaba Ismail
- KNU G-LAMP Project Group, KNU Institute of Basic Sciences, BK21 FOUR KNU Creative BioResearch Group, School of Life Sciences, College of Natural Sciences, Kyungpook National University, Daegu 41566, Korea
| | - Hongchan Lee
- KNU G-LAMP Project Group, KNU Institute of Basic Sciences, BK21 FOUR KNU Creative BioResearch Group, School of Life Sciences, College of Natural Sciences, Kyungpook National University, Daegu 41566, Korea
| | - Hong-Yeoul Ryu
- KNU G-LAMP Project Group, KNU Institute of Basic Sciences, BK21 FOUR KNU Creative BioResearch Group, School of Life Sciences, College of Natural Sciences, Kyungpook National University, Daegu 41566, Korea
| | - Dong-Hyung Cho
- KNU G-LAMP Project Group, KNU Institute of Basic Sciences, BK21 FOUR KNU Creative BioResearch Group, School of Life Sciences, College of Natural Sciences, Kyungpook National University, Daegu 41566, Korea
| | - Taeg Kyu Kwon
- Department of Immunology, School of Medicine, Keimyung University, Daegu 41566, Korea
| | - Tae Joo Park
- Department of Biological Sciences, College of Information-Bio Convergence, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Korea
| | - Taejoon Kwon
- Department of Biomedical Engineering, College of Information-Bio Convergence, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Korea
| | - Hyun-Shik Lee
- KNU G-LAMP Project Group, KNU Institute of Basic Sciences, BK21 FOUR KNU Creative BioResearch Group, School of Life Sciences, College of Natural Sciences, Kyungpook National University, Daegu 41566, Korea.
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2
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Mai N, Wu L, Uruk G, Mocanu E, Swanson RA. Bioenergetic and excitotoxic determinants of cofilactin rod formation. J Neurochem 2024; 168:899-909. [PMID: 38299375 PMCID: PMC11102304 DOI: 10.1111/jnc.16065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 01/12/2024] [Accepted: 01/16/2024] [Indexed: 02/02/2024]
Abstract
Cofilactin rods (CARs), which are 1:1 aggregates of cofilin-1 and actin, lead to neurite loss in ischemic stroke and other disorders. The biochemical pathways driving CAR formation are well-established, but how these pathways are engaged under ischemic conditions is less clear. Brain ischemia produces both ATP depletion and glutamate excitotoxicity, both of which have been shown to drive CAR formation in other settings. Here, we show that CARs are formed in cultured neurons exposed to ischemia-like conditions: oxygen-glucose deprivation (OGD), glutamate, or oxidative stress. Of these conditions, only OGD produced significant ATP depletion, showing that ATP depletion is not required for CAR formation. Moreover, the OGD-induced CAR formation was blocked by the glutamate receptor antagonists MK-801 and kynurenic acid; the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitors GSK2795039 and apocynin; as well as an ROS scavenger. The findings identify a biochemical pathway leading from OGD to CAR formation in which the glutamate release induced by energy failure leads to activation of neuronal glutamate receptors, which in turn activates NADPH oxidase to generate oxidative stress and CARs.
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Affiliation(s)
- Nguyen Mai
- Department of Neurology, University of California, San Francisco, California, USA
- Neurology Service, San Francisco Veterans Affairs Medical Center, San Francisco, California, USA
| | - Long Wu
- Department of Neurology, University of California, San Francisco, California, USA
- Neurology Service, San Francisco Veterans Affairs Medical Center, San Francisco, California, USA
| | - Gökhan Uruk
- Department of Neurology, University of California, San Francisco, California, USA
- Neurology Service, San Francisco Veterans Affairs Medical Center, San Francisco, California, USA
| | - Ebony Mocanu
- Department of Neurology, University of California, San Francisco, California, USA
- Neurology Service, San Francisco Veterans Affairs Medical Center, San Francisco, California, USA
| | - Raymond A. Swanson
- Department of Neurology, University of California, San Francisco, California, USA
- Neurology Service, San Francisco Veterans Affairs Medical Center, San Francisco, California, USA
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3
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Uruk G, Mocanu E, Shaw AE, Bamburg JR, Swanson RA. Cofilactin rod formation mediates inflammation-induced neurite degeneration. Cell Rep 2024; 43:113914. [PMID: 38451813 PMCID: PMC11068216 DOI: 10.1016/j.celrep.2024.113914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 01/17/2024] [Accepted: 02/19/2024] [Indexed: 03/09/2024] Open
Abstract
Stroke, trauma, and neurodegenerative disorders cause loss of neurites (axons and dendrites) in addition to neuronal death. Neurite loss may result directly from a primary insult, secondary to parental neuron death, or secondary to a post-injury inflammatory response. Here, we use lipopolysaccharide and the alarmin S100β to selectively evaluate neurite loss caused by the inflammatory response. Activation of microglia and infiltrating macrophages by these stimuli causes neurite loss that far exceeds neuronal death, both in vitro and in vivo. Neurite loss is accompanied by the formation of cofilactin rods and aggregates (CARs), which are polymers of cofilin-1 and actin induced by oxidative stress and other factors. Mice deficient in either cofilin-1 or the superoxide-generating enzyme NADPH oxidase-2 show reduced CAR formation, neurite loss, and motor impairment. The findings identify a mechanism by which inflammation leads to neurite loss via CAR formation and highlight the relevance of neurite loss to functional impairment.
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Affiliation(s)
- Gökhan Uruk
- Department of Neurology, University of California, San Francisco, San Francisco, CA, USA; Neurology Service, San Francisco Veterans Affairs Health Care System, San Francisco, CA, USA
| | - Ebony Mocanu
- Department of Neurology, University of California, San Francisco, San Francisco, CA, USA; Neurology Service, San Francisco Veterans Affairs Health Care System, San Francisco, CA, USA
| | - Alisa E Shaw
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
| | - James R Bamburg
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
| | - Raymond A Swanson
- Department of Neurology, University of California, San Francisco, San Francisco, CA, USA; Neurology Service, San Francisco Veterans Affairs Health Care System, San Francisco, CA, USA.
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4
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Santos CV, Rogers SL, Carter AP. CryoET shows cofilactin filaments inside the microtubule lumen. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.31.535077. [PMID: 37034688 PMCID: PMC10081314 DOI: 10.1101/2023.03.31.535077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/20/2023]
Abstract
Cytoplasmic microtubules are tubular polymers that can harbor small proteins or filaments inside their lumen. The identity of these objects and what causes their accumulation has not been conclusively established. Here, we used cryogenic electron tomography (cryoET) of Drosophila S2 cell protrusions and found filaments inside the microtubule lumen, which resemble those reported recently in human HAP1 cells. The frequency of these filaments increased upon inhibition of the sarco/endoplasmic reticulum Ca 2+ ATPase (SERCA) with the small-molecule drug thapsigargin. Subtomogram averaging showed that the luminal filaments adopt a helical structure reminiscent of cofilin-bound actin (cofilactin). Consistent with this, cofilin was activated in cells under the same conditions that increased luminal filament occurrence. Furthermore, RNAi knock-down of cofilin reduced the frequency of luminal filaments with cofilactin morphology. These results suggest that cofilin activation stimulates its accumulation on actin filaments inside the microtubule lumen.
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Affiliation(s)
| | - Stephen L. Rogers
- Department of Biology and Integrative Program for Biological and Genome Sciences, The University of North Carolina at Chapel Hill
| | - Andrew P. Carter
- MRC Laboratory of Molecular Biology, Francis Crick Ave, Cambridge, CB2 0QH, UK
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5
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Rumpf S, Sanal N, Marzano M. Energy metabolic pathways in neuronal development and function. OXFORD OPEN NEUROSCIENCE 2023; 2:kvad004. [PMID: 38596236 PMCID: PMC10913822 DOI: 10.1093/oons/kvad004] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 03/18/2023] [Accepted: 03/20/2023] [Indexed: 04/11/2024]
Abstract
Neuronal development and function are known to be among the most energy-demanding functions of the body. Constant energetic support is therefore crucial at all stages of a neuron's life. The two main adenosine triphosphate (ATP)-producing pathways in cells are glycolysis and oxidative phosphorylation. Glycolysis has a relatively low yield but provides fast ATP and enables the metabolic versatility needed in dividing neuronal stem cells. Oxidative phosphorylation, on the other hand, is highly efficient and therefore thought to provide most or all ATP in differentiated neurons. However, it has recently become clear that due to their distinct properties, both pathways are required to fully satisfy neuronal energy demands during development and function. Here, we provide an overview of how glycolysis and oxidative phosphorylation are used in neurons during development and function.
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Affiliation(s)
- Sebastian Rumpf
- Correspondence address. Multiscale Imaging Center, University of Münster, Röntgenstrasse 16, 48149 Münster, Germany. E-mail:
| | - Neeraja Sanal
- Multiscale Imaging Center, University of Münster, Röntgenstrasse 16, 48149 Münster, Germany
| | - Marco Marzano
- Multiscale Imaging Center, University of Münster, Röntgenstrasse 16, 48149 Münster, Germany
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6
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Wurz AI, Schulz AM, O’Bryant CT, Sharp JF, Hughes RM. Cytoskeletal dysregulation and neurodegenerative disease: Formation, monitoring, and inhibition of cofilin-actin rods. Front Cell Neurosci 2022; 16:982074. [PMID: 36212686 PMCID: PMC9535683 DOI: 10.3389/fncel.2022.982074] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 08/31/2022] [Indexed: 12/04/2022] Open
Abstract
The presence of atypical cytoskeletal dynamics, structures, and associated morphologies is a common theme uniting numerous diseases and developmental disorders. In particular, cytoskeletal dysregulation is a common cellular feature of Alzheimer’s disease, Parkinson’s disease, and Huntington’s disease. While the numerous activators and inhibitors of dysregulation present complexities for characterizing these elements as byproducts or initiators of the disease state, it is increasingly clear that a better understanding of these anomalies is critical for advancing the state of knowledge and plan of therapeutic attack. In this review, we focus on the hallmarks of cytoskeletal dysregulation that are associated with cofilin-linked actin regulation, with a particular emphasis on the formation, monitoring, and inhibition of cofilin-actin rods. We also review actin-associated proteins other than cofilin with links to cytoskeleton-associated neurodegenerative processes, recognizing that cofilin-actin rods comprise one strand of a vast web of interactions that occur as a result of cytoskeletal dysregulation. Our aim is to present a current perspective on cytoskeletal dysregulation, connecting recent developments in our understanding with emerging strategies for biosensing and biomimicry that will help shape future directions of the field.
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Affiliation(s)
- Anna I. Wurz
- Department of Chemistry, East Carolina University, Greenville, NC, United States
| | - Anna M. Schulz
- Department of Chemistry, East Carolina University, Greenville, NC, United States
| | - Collin T. O’Bryant
- Department of Chemistry, East Carolina University, Greenville, NC, United States
| | - Josephine F. Sharp
- Department of Chemistry, Notre Dame College, South Euclid, OH, United States
| | - Robert M. Hughes
- Department of Chemistry, East Carolina University, Greenville, NC, United States
- *Correspondence: Robert M. Hughes,
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7
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Yadav T, Gau D, Roy P. Mitochondria-actin cytoskeleton crosstalk in cell migration. J Cell Physiol 2022; 237:2387-2403. [PMID: 35342955 PMCID: PMC9945482 DOI: 10.1002/jcp.30729] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 03/06/2022] [Accepted: 03/11/2022] [Indexed: 12/15/2022]
Abstract
Mitochondria perform diverse functions in the cell and their roles during processes such as cell survival, differentiation, and migration are increasingly being appreciated. Mitochondrial and actin cytoskeletal networks not only interact with each other, but this multifaceted interaction shapes their functional dynamics. The interrelation between mitochondria and the actin cytoskeleton extends far beyond the requirement of mitochondrial ATP generation to power actin dynamics, and impinges upon several major aspects of cellular physiology. Being situated at the hub of cell signaling pathways, mitochondrial function can alter the activity of actin regulatory proteins and therefore modulate the processes downstream of actin dynamics such as cellular migration. As we will discuss, this regulation is highly nuanced and operates at multiple levels allowing mitochondria to occupy a strategic position in the regulation of migration, as well as pathological events that rely on aberrant cell motility such as cancer metastasis. In this review, we summarize the crosstalk that exists between mitochondria and actin regulatory proteins, and further emphasize on how this interaction holds importance in cell migration in normal as well as dysregulated scenarios as in cancer.
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Affiliation(s)
- Tarun Yadav
- Biology, Indian Institute of Science Education and Research, Pune
| | - David Gau
- Bioengineering, University of Pittsburgh, USA
| | - Partha Roy
- Bioengineering, University of Pittsburgh, USA,Pathology, University of Pittsburgh, USA
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8
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Bamburg JR. Meet the Editorial Board Member. Curr Neuropharmacol 2022. [PMCID: PMC9413792 DOI: 10.2174/1570159x2002220216142719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- James R. Bamburg
- Department of Biochemistry and Molecular Biology
Molecular and Radiological Bioscience Building, Room 235
Fort Collins, CO 80523-1870
Colorado State University
USA
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9
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Ishikawa-Ankerhold HC, Kurzbach S, Kinali AS, Müller-Taubenberger A. Formation of Cytoplasmic Actin-Cofilin Rods is Triggered by Metabolic Stress and Changes in Cellular pH. Front Cell Dev Biol 2021; 9:742310. [PMID: 34869330 PMCID: PMC8635511 DOI: 10.3389/fcell.2021.742310] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 10/27/2021] [Indexed: 11/13/2022] Open
Abstract
Actin dynamics plays a crucial role in regulating essential cell functions and thereby is largely responsible to a considerable extent for cellular energy consumption. Certain pathological conditions in humans, like neurological disorders such as Alzheimer’s disease or amyotrophic lateral sclerosis (ALS) as well as variants of nemaline myopathy are associated with cytoskeletal abnormalities, so-called actin-cofilin rods. Actin-cofilin rods are aggregates consisting mainly of actin and cofilin, which are formed as a result of cellular stress and thereby help to ensure the survival of cells under unfavorable conditions. We have used Dictyostelium discoideum, an established model system for cytoskeletal research to study formation and principles of cytoplasmic actin rod assembly in response to energy depletion. Experimentally, depletion of ATP was provoked by addition of either sodium azide, dinitrophenol, or 2-deoxy-glucose, and the formation of rod assembly was recorded by live-cell imaging. Furthermore, we show that hyperosmotic shock induces actin-cofilin rods, and that a drop in the intracellular pH accompanies this condition. Our data reveal that acidification of the cytoplasm can induce the formation of actin-cofilin rods to varying degrees and suggest that a local reduction in cellular pH may be a cause for the formation of cytoplasmic rods. We hypothesize that local phase separation mechanistically triggers the assembly of actin-cofilin rods and thereby influences the material properties of actin structures.
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Affiliation(s)
- Hellen C Ishikawa-Ankerhold
- Department of Internal Medicine I, University Hospital, LMU Munich, Munich, Germany.,Walter Brendel Centre of Experimental Medicine, University Hospital, LMU Munich, Munich, Germany
| | - Sophie Kurzbach
- Department of Cell Biology (Anatomy III), Biomedical Center (BMC), LMU Munich, Munich, Germany
| | - Arzu S Kinali
- Walter Brendel Centre of Experimental Medicine, University Hospital, LMU Munich, Munich, Germany
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10
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Bamburg JR, Minamide LS, Wiggan O, Tahtamouni LH, Kuhn TB. Cofilin and Actin Dynamics: Multiple Modes of Regulation and Their Impacts in Neuronal Development and Degeneration. Cells 2021; 10:cells10102726. [PMID: 34685706 PMCID: PMC8534876 DOI: 10.3390/cells10102726] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 10/06/2021] [Accepted: 10/07/2021] [Indexed: 02/06/2023] Open
Abstract
Proteins of the actin depolymerizing factor (ADF)/cofilin family are ubiquitous among eukaryotes and are essential regulators of actin dynamics and function. Mammalian neurons express cofilin-1 as the major isoform, but ADF and cofilin-2 are also expressed. All isoforms bind preferentially and cooperatively along ADP-subunits in F-actin, affecting the filament helical rotation, and when either alone or when enhanced by other proteins, promotes filament severing and subunit turnover. Although self-regulating cofilin-mediated actin dynamics can drive motility without post-translational regulation, cells utilize many mechanisms to locally control cofilin, including cooperation/competition with other proteins. Newly identified post-translational modifications function with or are independent from the well-established phosphorylation of serine 3 and provide unexplored avenues for isoform specific regulation. Cofilin modulates actin transport and function in the nucleus as well as actin organization associated with mitochondrial fission and mitophagy. Under neuronal stress conditions, cofilin-saturated F-actin fragments can undergo oxidative cross-linking and bundle together to form cofilin-actin rods. Rods form in abundance within neurons around brain ischemic lesions and can be rapidly induced in neurites of most hippocampal and cortical neurons through energy depletion or glutamate-induced excitotoxicity. In ~20% of rodent hippocampal neurons, rods form more slowly in a receptor-mediated process triggered by factors intimately connected to disease-related dementias, e.g., amyloid-β in Alzheimer’s disease. This rod-inducing pathway requires a cellular prion protein, NADPH oxidase, and G-protein coupled receptors, e.g., CXCR4 and CCR5. Here, we will review many aspects of cofilin regulation and its contribution to synaptic loss and pathology of neurodegenerative diseases.
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Affiliation(s)
- James R. Bamburg
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA; (L.S.M.); (O.W.); (L.H.T.); (T.B.K.)
- Correspondence: ; Tel.: +1-970-988-9120; Fax: +1-970-491-0494
| | - Laurie S. Minamide
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA; (L.S.M.); (O.W.); (L.H.T.); (T.B.K.)
| | - O’Neil Wiggan
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA; (L.S.M.); (O.W.); (L.H.T.); (T.B.K.)
| | - Lubna H. Tahtamouni
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA; (L.S.M.); (O.W.); (L.H.T.); (T.B.K.)
- Department of Biology and Biotechnology, The Hashemite University, Zarqa 13115, Jordan
| | - Thomas B. Kuhn
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA; (L.S.M.); (O.W.); (L.H.T.); (T.B.K.)
- Department of Chemistry and Biochemistry, University of Alaska, Fairbanks, AK 99775, USA
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11
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Different changes in pre- and postsynaptic components in the hippocampal CA1 subfield after transient global cerebral ischemia. Brain Struct Funct 2021; 227:345-360. [PMID: 34626230 DOI: 10.1007/s00429-021-02404-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 09/29/2021] [Indexed: 10/20/2022]
Abstract
To date, ischemia-induced damage to dendritic spines has attracted considerable attention, while the possible effects of ischemia on presynaptic components has received relatively less attention. To further examine ischemia-induced changes in pre- and postsynaptic specializations in the hippocampal CA1 subfield, we modeled global cerebral ischemia with two-stage 4-vessel-occlusion in rats, and found that three postsynaptic markers, microtubule-associated protein 2 (MAP2), postsynaptic density protein 95 (PSD95), and filamentous F-actin (F-actin), were all substantially decreased in the CA1 subfield after ischemia/reperfusion (I/R). Although no significant change was detected in synapsin I, a presynaptic marker, in the CA1 subfield at the protein level, confocal microscopy revealed that the number and size of synapsin I puncta were significantly changed in the CA1 stratum radiatum after I/R. The size of synapsin I puncta became slightly, but significantly reduced on Day 1.5 after I/R. From Days 2 to 7 after I/R, the number of synapsin I puncta became moderately decreased, while the size of synapsin I puncta was significantly increased. Interestingly, some enlarged puncta of synapsin I were observed in close proximity to the dendritic shafts of CA1 pyramidal cells. Due to the more substantial decrease in the number of F-actin puncta, the ratio of synapsin I/F-actin puncta was significantly increased after I/R. The decrease in synapsin I puncta size in the early stage of I/R may be the result of excessive neurotransmitter release due to I/R-induced hyperexcitability in CA3 pyramidal cells, while the increase in synapsin I puncta in the later stage of I/R may reflect a disability of synaptic vesicle release due to the loss of postsynaptic contacts.
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12
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Lapeña-Luzón T, Rodríguez LR, Beltran-Beltran V, Benetó N, Pallardó FV, Gonzalez-Cabo P. Cofilin and Neurodegeneration: New Functions for an Old but Gold Protein. Brain Sci 2021; 11:brainsci11070954. [PMID: 34356188 PMCID: PMC8303701 DOI: 10.3390/brainsci11070954] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/12/2021] [Accepted: 07/16/2021] [Indexed: 12/11/2022] Open
Abstract
Cofilin is an actin-binding protein that plays a major role in the regulation of actin dynamics, an essential cellular process. This protein has emerged as a crucial molecule for functions of the nervous system including motility and guidance of the neuronal growth cone, dendritic spine organization, axonal branching, and synaptic signalling. Recently, other important functions in cell biology such as apoptosis or the control of mitochondrial function have been attributed to cofilin. Moreover, novel mechanisms of cofilin function regulation have also been described. The activity of cofilin is controlled by complex regulatory mechanisms, with phosphorylation being the most important, since the addition of a phosphate group to cofilin renders it inactive. Due to its participation in a wide variety of key processes in the cell, cofilin has been related to a great variety of pathologies, among which neurodegenerative diseases have attracted great interest. In this review, we summarized the functions of cofilin and its regulation, emphasizing how defects in these processes have been related to different neurodegenerative diseases.
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Affiliation(s)
- Tamara Lapeña-Luzón
- Department of Physiology, Faculty of Medicine and Dentistry, University of Valencia, 46010 Valencia, Spain; (T.L.-L.); (L.R.R.); (V.B.-B.); (N.B.); (F.V.P.)
- Biomedical Research Institute INCLIVA, 46010 Valencia, Spain
- CIBER de Enfermedades Raras (CIBERER), 46010 Valencia, Spain
| | - Laura R. Rodríguez
- Department of Physiology, Faculty of Medicine and Dentistry, University of Valencia, 46010 Valencia, Spain; (T.L.-L.); (L.R.R.); (V.B.-B.); (N.B.); (F.V.P.)
- Biomedical Research Institute INCLIVA, 46010 Valencia, Spain
- CIBER de Enfermedades Raras (CIBERER), 46010 Valencia, Spain
| | - Vicent Beltran-Beltran
- Department of Physiology, Faculty of Medicine and Dentistry, University of Valencia, 46010 Valencia, Spain; (T.L.-L.); (L.R.R.); (V.B.-B.); (N.B.); (F.V.P.)
| | - Noelia Benetó
- Department of Physiology, Faculty of Medicine and Dentistry, University of Valencia, 46010 Valencia, Spain; (T.L.-L.); (L.R.R.); (V.B.-B.); (N.B.); (F.V.P.)
- Biomedical Research Institute INCLIVA, 46010 Valencia, Spain
- CIBER de Enfermedades Raras (CIBERER), 46010 Valencia, Spain
| | - Federico V. Pallardó
- Department of Physiology, Faculty of Medicine and Dentistry, University of Valencia, 46010 Valencia, Spain; (T.L.-L.); (L.R.R.); (V.B.-B.); (N.B.); (F.V.P.)
- Biomedical Research Institute INCLIVA, 46010 Valencia, Spain
- CIBER de Enfermedades Raras (CIBERER), 46010 Valencia, Spain
| | - Pilar Gonzalez-Cabo
- Department of Physiology, Faculty of Medicine and Dentistry, University of Valencia, 46010 Valencia, Spain; (T.L.-L.); (L.R.R.); (V.B.-B.); (N.B.); (F.V.P.)
- Biomedical Research Institute INCLIVA, 46010 Valencia, Spain
- CIBER de Enfermedades Raras (CIBERER), 46010 Valencia, Spain
- Correspondence:
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13
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Walter LM, Rademacher S, Pich A, Claus P. Profilin2 regulates actin rod assembly in neuronal cells. Sci Rep 2021; 11:10287. [PMID: 33986363 PMCID: PMC8119500 DOI: 10.1038/s41598-021-89397-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/26/2021] [Indexed: 12/13/2022] Open
Abstract
Nuclear and cytoplasmic actin-cofilin rods are formed transiently under stress conditions to reduce actin filament turnover and ATP hydrolysis. The persistence of these structures has been implicated in disease pathology of several neurological disorders. Recently, the presence of actin rods has been discovered in Spinal Muscular Atrophy (SMA), a neurodegenerative disease affecting predominantly motoneurons leading to muscle weakness and atrophy. This finding underlined the importance of dysregulated actin dynamics in motoneuron loss in SMA. In this study, we characterized actin rods formed in a SMA cell culture model analyzing their composition by LC–MS-based proteomics. Besides actin and cofilin, we identified proteins involved in processes such as ubiquitination, translation or protein folding to be bound to actin rods. This suggests their sequestration to actin rods, thus impairing important cellular functions. Moreover, we showed the involvement of the cytoskeletal protein profilin2 and its upstream effectors RhoA/ROCK in actin rod assembly in SMA. These findings implicate that the formation of actin rods exerts detrimental effects on motoneuron homeostasis by affecting actin dynamics and disturbing essential cellular pathways.
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Affiliation(s)
- Lisa Marie Walter
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
| | - Sebastian Rademacher
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany.,Institute of Biochemistry, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Andreas Pich
- Institute of Toxicology and Core Unit Proteomics, Hannover Medical School, Hannover, Germany
| | - Peter Claus
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Germany. .,Center for Systems Neuroscience, Hannover, Germany.
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14
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New Insights into Cellular Functions of Nuclear Actin. BIOLOGY 2021; 10:biology10040304. [PMID: 33916969 PMCID: PMC8067577 DOI: 10.3390/biology10040304] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 03/30/2021] [Accepted: 04/01/2021] [Indexed: 12/12/2022]
Abstract
Simple Summary It is well known that actin forms a cytoplasmic network of microfilaments, the part of the cytoskeleton, in the cytoplasm of eukaryotic cells. The presence of nuclear actin was elusive for a very long time. Now, there is a very strong evidence that actin plays many important roles in the nucleus. Here, we discuss the recently discovered functions of the nuclear actin pool. Actin does not have nuclear localization signal (NLS), so its import to the nucleus is facilitated by the NLS-containing proteins. Nuclear actin plays a role in the maintenance of the nuclear structure and the nuclear envelope breakdown. It is also involved in chromatin remodeling, and chromatin and nucleosome movement necessary for DNA recombination, repair, and the initiation of transcription. It also binds RNA polymerases, promoting transcription. Because of the multifaceted role of nuclear actin, the future challenge will be to further define its functions in various cellular processes and diseases. Abstract Actin is one of the most abundant proteins in eukaryotic cells. There are different pools of nuclear actin often undetectable by conventional staining and commercial antibodies used to identify cytoplasmic actin. With the development of more sophisticated imaging and analytical techniques, it became clear that nuclear actin plays a crucial role in shaping the chromatin, genomic, and epigenetic landscape, transcriptional regulation, and DNA repair. This multifaceted role of nuclear actin is not only important for the function of the individual cell but also for the establishment of cell fate, and tissue and organ differentiation during development. Moreover, the changes in the nuclear, chromatin, and genomic architecture are preamble to various diseases. Here, we discuss some of the newly described functions of nuclear actin.
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15
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A Progressive Loss of phosphoSer138-Profilin Aligns with Symptomatic Course in the R6/2 Mouse Model of Huntington's Disease: Possible Sex-Dependent Signaling. Cell Mol Neurobiol 2020; 42:871-888. [PMID: 33108594 PMCID: PMC8891113 DOI: 10.1007/s10571-020-00984-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 10/16/2020] [Indexed: 12/20/2022]
Abstract
The R6/2 transgenic mouse model of Huntington’s disease (HD) carries several copies of exon1 of the huntingtin gene that contains a highly pathogenic 120 CAG-repeat expansion. We used kinome analysis to screen for kinase activity patterns in neural tissues from wildtype (WT) and R6/2 mice at a pre-symptomatic (e.g., embryonic) and symptomatic (e.g., between 3 and 10 weeks postnatal) time points. We identified changes in several signaling cascades, for example, the Akt/FoxO3/CDK2, mTOR/ULK1, and RAF/MEK/CREB pathways. We also identified the Rho-Rac GTPase cascade that contributes to cytoskeleton organization through modulation of the actin-binding proteins, cofilin and profilin. Immunoblotting revealed higher levels of phosphoSer138-profilin in embryonic R6/2 mouse samples (cf. WT mice) that diminish progressively and significantly over the postnatal, symptomatic course of the disease. We detected sex- and genotype-dependent patterns in the phosphorylation of actin-regulators such a ROCK2, PAK, LIMK1, cofilin, and SSH1L, yet none of these aligned consistently with the changing levels of phosphoSer138-profilin. This could be reflecting an imbalance in the sequential influences these regulators are known to exert on actin signaling. The translational potential of these observations was inferred from preliminary observations of changes in LIMK-cofilin signaling and loss of neurite integrity in neural stem cells derived from an HD patient (versus a healthy control). Our observations suggest that a pre-symptomatic, neurodevelopmental onset of change in the phosphorylation of Ser138-profilin, potentially downstream of distinct signaling changes in male and female mice, could be contributing to cytoskeletal phenotypes in the R6/2 mouse model of HD pathology.
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16
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Wang Y, Song X, Wang Y, Huang L, Luo W, Li F, Qin S, Wang Y, Xiao J, Wu Y, Jin F, Kitazato K, Wang Y. Dysregulation of cofilin-1 activity-the missing link between herpes simplex virus type-1 infection and Alzheimer's disease. Crit Rev Microbiol 2020; 46:381-396. [PMID: 32715819 DOI: 10.1080/1040841x.2020.1794789] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Alzheimer's disease (AD) is a multifactorial disease triggered by environmental factors in combination with genetic predisposition. Infectious agents, in particular herpes simplex virus type 1 (HSV-1), are gradually being recognised as important factors affecting the development of AD. However, the mechanism linking HSV-1 and AD remains unknown. Of note, HSV-1 manipulates the activity of cofilin-1 to ensure their efficient infection in neuron cells. Cofilin-1, the main regulator of actin cytoskeleton reorganization, is implicating for the plastic of dendritic spines and axon regeneration of neuronal cells. Moreover, dysfunction of cofilin-1 is observed in most AD patients, as well as in mice with AD and ageing. Further, inhibition of cofilin-1 activity ameliorates the host cognitive impairment in an animal model of AD. Together, dysregulation of cofilin-1 led by HSV-1 infection is a potential link between HSV-1 and AD. Herein, we critically summarize the role of cofilin-1-mediated actin dynamics in both HSV-1 infection and AD, respectively. We also propose several hypotheses regarding the connecting roles of cofilin-1 dysregulation in HSV-1 infection and AD. Our review provides a foundation for future studies targeting individuals carrying HSV-1 in combination with cofilin-1 to promote a more individualised approach for treatment and prevention of AD.
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Affiliation(s)
- Yiliang Wang
- Guangzhou Jinan Biomedicine Research and Development Center, Institute of Biomedicine, College of Life Science and Technology, Jinan University, Guangzhou, PR China.,Key Laboratory of Virology of Guangzhou, Jinan University, Guangzhou, PR China.,Key Laboratory of Bioengineering Medicine of Guangdong Province, Jinan University, Guangzhou, PR China
| | - Xiaowei Song
- Guangzhou Jinan Biomedicine Research and Development Center, Institute of Biomedicine, College of Life Science and Technology, Jinan University, Guangzhou, PR China.,Key Laboratory of Virology of Guangzhou, Jinan University, Guangzhou, PR China.,Key Laboratory of Bioengineering Medicine of Guangdong Province, Jinan University, Guangzhou, PR China
| | - Yun Wang
- Department of Obstetrics and gynecology, The First affiliated hospital of Jinan University, Guangzhou, PR China
| | - Lianzhou Huang
- Guangzhou Jinan Biomedicine Research and Development Center, Institute of Biomedicine, College of Life Science and Technology, Jinan University, Guangzhou, PR China.,Key Laboratory of Virology of Guangzhou, Jinan University, Guangzhou, PR China.,Key Laboratory of Bioengineering Medicine of Guangdong Province, Jinan University, Guangzhou, PR China
| | - Weisheng Luo
- Guangzhou Jinan Biomedicine Research and Development Center, Institute of Biomedicine, College of Life Science and Technology, Jinan University, Guangzhou, PR China.,Key Laboratory of Virology of Guangzhou, Jinan University, Guangzhou, PR China.,Key Laboratory of Bioengineering Medicine of Guangdong Province, Jinan University, Guangzhou, PR China
| | - Feng Li
- Guangzhou Jinan Biomedicine Research and Development Center, Institute of Biomedicine, College of Life Science and Technology, Jinan University, Guangzhou, PR China.,Key Laboratory of Virology of Guangzhou, Jinan University, Guangzhou, PR China.,Key Laboratory of Bioengineering Medicine of Guangdong Province, Jinan University, Guangzhou, PR China
| | - Shurong Qin
- Guangzhou Jinan Biomedicine Research and Development Center, Institute of Biomedicine, College of Life Science and Technology, Jinan University, Guangzhou, PR China.,Key Laboratory of Virology of Guangzhou, Jinan University, Guangzhou, PR China.,Key Laboratory of Bioengineering Medicine of Guangdong Province, Jinan University, Guangzhou, PR China
| | - Yuan Wang
- Guangzhou Jinan Biomedicine Research and Development Center, Institute of Biomedicine, College of Life Science and Technology, Jinan University, Guangzhou, PR China.,Key Laboratory of Virology of Guangzhou, Jinan University, Guangzhou, PR China.,Key Laboratory of Bioengineering Medicine of Guangdong Province, Jinan University, Guangzhou, PR China
| | - Ji Xiao
- Guangzhou Jinan Biomedicine Research and Development Center, Institute of Biomedicine, College of Life Science and Technology, Jinan University, Guangzhou, PR China.,Key Laboratory of Virology of Guangzhou, Jinan University, Guangzhou, PR China.,Key Laboratory of Bioengineering Medicine of Guangdong Province, Jinan University, Guangzhou, PR China
| | - Yanting Wu
- Guangzhou Jinan Biomedicine Research and Development Center, Institute of Biomedicine, College of Life Science and Technology, Jinan University, Guangzhou, PR China.,Key Laboratory of Virology of Guangzhou, Jinan University, Guangzhou, PR China.,Key Laboratory of Bioengineering Medicine of Guangdong Province, Jinan University, Guangzhou, PR China
| | - Fujun Jin
- Guangzhou Jinan Biomedicine Research and Development Center, Institute of Biomedicine, College of Life Science and Technology, Jinan University, Guangzhou, PR China.,Key Laboratory of Virology of Guangzhou, Jinan University, Guangzhou, PR China.,Key Laboratory of Bioengineering Medicine of Guangdong Province, Jinan University, Guangzhou, PR China
| | - Kaio Kitazato
- Division of Molecular Pharmacology of Infectious Agents, Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Yifei Wang
- Guangzhou Jinan Biomedicine Research and Development Center, Institute of Biomedicine, College of Life Science and Technology, Jinan University, Guangzhou, PR China.,Key Laboratory of Virology of Guangzhou, Jinan University, Guangzhou, PR China.,Key Laboratory of Bioengineering Medicine of Guangdong Province, Jinan University, Guangzhou, PR China
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17
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Cofilin-Mediated Actin Stress Response Is Maladaptive in Heat-Stressed Embryos. Cell Rep 2020; 26:3493-3501.e4. [PMID: 30917306 PMCID: PMC6447309 DOI: 10.1016/j.celrep.2019.02.092] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 01/22/2019] [Accepted: 02/21/2019] [Indexed: 01/04/2023] Open
Abstract
Environmental stress threatens the fidelity of embryonic morphogenesis. Heat, for example, is a teratogen. Yet how heat affects morphogenesis is poorly understood. Here, we identify a heat-inducible actin stress response (ASR) in Drosophila embryos that is mediated by the activation of the actin regulator Cofilin. Similar to ASR in adult mammalian cells, heat stress in fly embryos triggers the assembly of intra-nuclear actin rods. Rods measure up to a few microns in length, and their assembly depends on elevated free nuclear actin concentration and Cofilin. Outside the nucleus, heat stress causes Cofilin-dependent destabilization of filamentous actin (F-actin) in actomyosin networks required for morphogenesis. F-actin destabilization increases the chance of morphogenesis mistakes. Blocking the ASR by reducing Cofilin dosage improves the viability of heat-stressed embryos. However, improved viability correlates with restoring F-actin stability, not rescuing morphogenesis. Thus, ASR endangers embryos, perhaps by shifting actin from cytoplasmic filaments to an elevated nuclear pool. Figard et al. show that heat stress induces an actin stress response (ASR) in early Drosophila embryos. This ASR is mediated by a heat-induced increase in Cofilin activity. Increased Cofilin activity destabilizes F-actin structures required for morphogenesis. In addition, the Cofilin-mediated ASR reduces embryo viability.
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18
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Biel N, Figard L, Sokac AM. Imaging Intranuclear Actin Rods in Live Heat Stressed Drosophila Embryos. J Vis Exp 2020. [PMID: 32478727 DOI: 10.3791/61297] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The purpose of this protocol is to visualize intranuclear actin rods that assemble in live Drosophila melanogaster embryos following heat stress. Actin rods are a hallmark of a conserved, inducible Actin Stress Response (ASR) that accompanies human pathologies, including neurodegenerative disease. Previously, we showed that the ASR contributes to morphogenesis failures and reduced viability of developing embryos. This protocol allows the continued study of mechanisms underlying actin rod assembly and the ASR in a model system that is highly amenable to imaging, genetics and biochemistry. Embryos are collected and mounted on a coverslip to prepare them for injection. Rhodamine-conjugated globular actin (G-actinRed) is diluted and loaded into a microneedle. A single injection is made into the center of each embryo. After injection, embryos are incubated at elevated temperature and intranuclear actin rods are then visualized by confocal microscopy. Fluorescence recovery after photobleaching (FRAP) experiments may be performed on the actin rods; and other actin-rich structures in the cytoplasm can also be imaged. We find that G-actinRed polymerizes like endogenous G-actin and does not, on its own, interfere with normal embryo development. One limitation of this protocol is that care must be taken during injection to avoid serious injury to the embryo. However, with practice, injecting G-actinRed into Drosophila embryos is a fast and reliable way to visualize actin rods and can easily be used with flies of any genotype or with the introduction of other cellular stresses, including hypoxia and oxidative stress.
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Affiliation(s)
- Natalie Biel
- Integrative Molecular and Biomedical Sciences, Baylor College of Medicine; Department of Cell and Molecular Biology, School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign
| | - Lauren Figard
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine
| | - Anna Marie Sokac
- Integrative Molecular and Biomedical Sciences, Baylor College of Medicine; Department of Cell and Molecular Biology, School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign; Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine;
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19
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Hoffmann L, Rust MB, Culmsee C. Actin(g) on mitochondria - a role for cofilin1 in neuronal cell death pathways. Biol Chem 2020; 400:1089-1097. [PMID: 31256058 DOI: 10.1515/hsz-2019-0120] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 04/16/2019] [Indexed: 11/15/2022]
Abstract
Actin dynamics, the coordinated assembly and disassembly of actin filaments (F-actin), are essential for fundamental cellular processes, including cell shaping and motility, cell division or organelle transport. Recent studies highlighted a novel role for actin dynamics in the regulation of mitochondrial morphology and function, for example, through mitochondrial recruitment of dynamin-related protein 1 (Drp1), a key factor in the mitochondrial fission machinery. Mitochondria are dynamic organelles, and permanent fission and fusion is essential to maintain their function in energy metabolism, calcium homeostasis and regulation of reactive oxygen species (ROS). Here, we summarize recent insights into the emerging role of cofilin1, a key regulator of actin dynamics, for mitochondrial shape and function under physiological conditions and during cellular stress, respectively. This is of peculiar importance in neurons, which are particularly prone to changes in actin regulation and mitochondrial integrity and function. In neurons, cofilin1 may contribute to degenerative processes through formation of cofilin-actin rods, and through enhanced mitochondrial fission, mitochondrial membrane permeabilization, and the release of cytochrome c. Overall, mitochondrial impairment induced by dysfunction of actin-regulating proteins such as cofilin1 emerge as important mechanisms of neuronal death with relevance to acute brain injury and neurodegenerative diseases, such as Parkinson's or Alzheimer's disease.
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Affiliation(s)
- Lena Hoffmann
- Institute of Pharmacology and Clinical Pharmacy, Biochemical-Pharmacological Center Marburg, University of Marburg, Karl-von-Frisch Straße 2, D-35043 Marburg, Germany.,Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus-Liebig-University Gießen, Hans-Meerwein-Straße 6, D-35032 Marburg, Germany
| | - Marco B Rust
- Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus-Liebig-University Gießen, Hans-Meerwein-Straße 6, D-35032 Marburg, Germany.,Molecular Neurobiology Group, Institute of Physiological Chemistry, Biochemical-Pharmacological Center Marburg, University of Marburg, Karl-von-Frisch Straße 2, D-35043 Marburg, Germany
| | - Carsten Culmsee
- Institute of Pharmacology and Clinical Pharmacy, Biochemical-Pharmacological Center Marburg, University of Marburg, Karl-von-Frisch Straße 2, D-35043 Marburg, Germany.,Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus-Liebig-University Gießen, Hans-Meerwein-Straße 6, D-35032 Marburg, Germany.,Third Affiliated Hospital, Zhengzhou University, Zhengzhou, China
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20
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Dendritic Spines in Alzheimer's Disease: How the Actin Cytoskeleton Contributes to Synaptic Failure. Int J Mol Sci 2020; 21:ijms21030908. [PMID: 32019166 PMCID: PMC7036943 DOI: 10.3390/ijms21030908] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 01/24/2020] [Accepted: 01/26/2020] [Indexed: 02/06/2023] Open
Abstract
Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by Aβ-driven synaptic dysfunction in the early phases of pathogenesis. In the synaptic context, the actin cytoskeleton is a crucial element to maintain the dendritic spine architecture and to orchestrate the spine’s morphology remodeling driven by synaptic activity. Indeed, spine shape and synaptic strength are strictly correlated and precisely governed during plasticity phenomena in order to convert short-term alterations of synaptic strength into long-lasting changes that are embedded in stable structural modification. These functional and structural modifications are considered the biological basis of learning and memory processes. In this review we discussed the existing evidence regarding the role of the spine actin cytoskeleton in AD synaptic failure. We revised the physiological function of the actin cytoskeleton in the spine shaping and the contribution of actin dynamics in the endocytosis mechanism. The internalization process is implicated in different aspects of AD since it controls both glutamate receptor membrane levels and amyloid generation. The detailed understanding of the mechanisms controlling the actin cytoskeleton in a unique biological context as the dendritic spine could pave the way to the development of innovative synapse-tailored therapeutic interventions and to the identification of novel biomarkers to monitor synaptic loss in AD.
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21
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Abstract
Aging brain becomes susceptible to neurodegenerative diseases due to the shifting of microglia and astrocyte phenotypes to an active “pro-inflammatory” state, causing chronic low-grade neuroinflammation. Despite the fact that the role of neuroinflammation during aging has been extensively studied in recent years, the underlying causes remain unclear. The identification of relevant proteins and understanding their potential roles in neuroinflammation can help explain their potential of becoming biomarkers in the aging brain and as drug targets for prevention and treatment. This will eventually reduce the chances of developing neurodegenerative diseases and promote healthier lives in the elderly. In this review, we have summarized the morphological and cellular changes in the aging brain, the effects of age-related neuroinflammation, and the potential role of cofilin-1 during neuroinflammation. We also discuss other factors contributing to brain aging and neuroinflammation.
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Affiliation(s)
- Amsha S Alsegiani
- Department of Medicinal and Biological Chemistry, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH, USA
| | - Zahoor A Shah
- Department of Medicinal and Biological Chemistry, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH, USA
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22
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Park CK, Horton NC. Structures, functions, and mechanisms of filament forming enzymes: a renaissance of enzyme filamentation. Biophys Rev 2019; 11:927-994. [PMID: 31734826 PMCID: PMC6874960 DOI: 10.1007/s12551-019-00602-6] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 10/24/2019] [Indexed: 12/19/2022] Open
Abstract
Filament formation by non-cytoskeletal enzymes has been known for decades, yet only relatively recently has its wide-spread role in enzyme regulation and biology come to be appreciated. This comprehensive review summarizes what is known for each enzyme confirmed to form filamentous structures in vitro, and for the many that are known only to form large self-assemblies within cells. For some enzymes, studies describing both the in vitro filamentous structures and cellular self-assembly formation are also known and described. Special attention is paid to the detailed structures of each type of enzyme filament, as well as the roles the structures play in enzyme regulation and in biology. Where it is known or hypothesized, the advantages conferred by enzyme filamentation are reviewed. Finally, the similarities, differences, and comparison to the SgrAI endonuclease system are also highlighted.
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Affiliation(s)
- Chad K. Park
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85721 USA
| | - Nancy C. Horton
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85721 USA
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23
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Shu L, Chen B, Chen B, Xu H, Wang G, Huang Y, Zhao Y, Gong H, Jiang M, Chen L, Liu X, Wang Y. Brain ischemic insult induces cofilin rod formation leading to synaptic dysfunction in neurons. J Cereb Blood Flow Metab 2019; 39:2181-2195. [PMID: 29932353 PMCID: PMC6827117 DOI: 10.1177/0271678x18785567] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Ischemic stroke not only induces neuron death in the infarct area but also structural and functional damage of the surviving neurons in the surrounding peri-infarct area. In the present study, we first identified cofilin rod, a pathological rod-like aggregation, formed in neurons of in vivo ischemic stroke animal model and induced neuronal impairment. Cofilin rods formed only on the ipsilateral side of the middle cerebral artery occlusion and reperfusion (MCAO-R) rat brain and showed the highest density in peri-infarct area. Our real-time live cell imaging, immunostaining and patch clamp studies showed that cofilin rod formation in neurons led to dendritic mitochondrial transportation failure, as well as impairment of synaptic structure and functions. Overexpression of LIM kinase or activation of its upstream regulator Rho, suppressed ischemia-induced cofilin rod formation and showed protective effect on synaptic function and structure impairment in both cultured neurons and MCAO-R rat model. In summary, our results demonstrate a novel mechanism of ischemic stroke-induced neuron injury in peri-infarct area and provide a potential target for the protection of neuronal structure and function against brain ischemia insult.
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Affiliation(s)
- Liang Shu
- Department of Neurology, State Key Laboratory for Medical Neurobiology, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China.,Department of Neurology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Ben Chen
- Department of Neurology, State Key Laboratory for Medical Neurobiology, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Bin Chen
- The Affiliated People's Hospital of Fujian University of Traditional Chinese Medicine, Collaborative Innovation Center for Rehabilitation Technology, TCM Rehabilitation Research Center of SATCM, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian, China
| | - Hai Xu
- Department of Neurology, State Key Laboratory for Medical Neurobiology, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Guoxiang Wang
- Department of Neurology, State Key Laboratory for Medical Neurobiology, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Yian Huang
- Department of Neurology, State Key Laboratory for Medical Neurobiology, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Yingya Zhao
- Department of Neurology, State Key Laboratory for Medical Neurobiology, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Hui Gong
- Department of Neurology, State Key Laboratory for Medical Neurobiology, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Min Jiang
- Department of Neurology, State Key Laboratory for Medical Neurobiology, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Lidian Chen
- The Affiliated People's Hospital of Fujian University of Traditional Chinese Medicine, Collaborative Innovation Center for Rehabilitation Technology, TCM Rehabilitation Research Center of SATCM, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian, China
| | - Xu Liu
- Department of Neurology, State Key Laboratory for Medical Neurobiology, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Yun Wang
- Department of Neurology, State Key Laboratory for Medical Neurobiology, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China
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24
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Sun Y, Liang L, Dong M, Li C, Liu Z, Gao H. Cofilin 2 in Serum as a Novel Biomarker for Alzheimer's Disease in Han Chinese. Front Aging Neurosci 2019; 11:214. [PMID: 31447667 PMCID: PMC6696795 DOI: 10.3389/fnagi.2019.00214] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 07/30/2019] [Indexed: 12/20/2022] Open
Abstract
The identification of biomarkers of Alzheimer’s disease (AD) is an important and urgent area of study, not only to aid in the early diagnosis of AD, but also to evaluate potentially new anti-AD drugs. The aim of this study was to explore cofilin 2 in serum as a novel biomarker for AD. The upregulation was observed in AD patients and different AD animal models compared to the controls, as well as in AD cell models. Memantine and donepezil can attenuate the upregulation of cofilin 2 expression in APP/PS1 mice. The serum levels of cofilin 2 in AD or mild cognitive impairment (MCI) patients were significantly higher compared to controls (AD: 167.9 ± 35.3 pg/mL; MCI: 115.9 ± 15.4 pg/mL; Control: 90.5 ± 27.1 pg/mL; p < 0.01). A significant correlation between cofilin 2 levels and cognitive decline was observed (r = –0.792; p < 0.001). The receiver operating characteristic curve (ROC) analysis showed the area under the curve (AUC) of cofilin 2 was 0.957, and the diagnostic accuracy was 80%, with 93% sensitivity and 87% specificity. The optimal cut-off value was 130.4 pg/ml. Our results indicate the possibility of serum cofilin 2 as a novel and non-invasive biomarker for AD. In addition, the expression of cofilin 2 was found to be significantly increased in AD compared to vascular dementia (VaD), and only an increased trend but not significant was detected in VaD compared to the controls. ROC analysis between AD and VaD showed that the AUC was 0.824, which could indicate a role of cofilin 2 as a biomarker in the differential diagnosis between AD and VaD.
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Affiliation(s)
- Yingni Sun
- School of Life Sciences, Ludong University, Yantai, China
| | - Lisheng Liang
- Department of Pain, Qingdao University Medical College Affiliated Yantai Yuhuangding Hospital, Yantai, China
| | - Meili Dong
- Central Sterile Supply Department, Qingdao University Medical College Affiliated Yantai Yuhuangding Hospital, Yantai, China
| | - Cong Li
- Chemical and Materials Engineering, University of Kentucky, Lexington, KY, United States
| | - Zhenzhen Liu
- Chemical Engineering and Materials Science, College of Chemistry, Shandong Normal University, Jinan, China
| | - Hongwei Gao
- School of Life Sciences, Ludong University, Yantai, China
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25
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Guo CY, Xiong TQ, Tan BH, Gui Y, Ye N, Li SL, Li YC. The temporal and spatial changes of actin cytoskeleton in the hippocampal CA1 neurons following transient global ischemia. Brain Res 2019; 1720:146297. [PMID: 31233713 DOI: 10.1016/j.brainres.2019.06.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Revised: 05/13/2019] [Accepted: 06/14/2019] [Indexed: 11/25/2022]
Abstract
Transient global ischemia usually results in delayed neuronal death in selective brain regions, prior to which a rapid loss of dendritic spines has been widely reported in these regions. Dendritic spines are characterized by a highly branched meshwork of actin cytoskeleton (F-actin), which is extremely vulnerable to the ATP-depleted conditions such as hypoxia/ischemia. However, the ischemia-induced changes of F-actin are still not clarified in the vulnerable brain areas. This study was designed to examine the temporal and spatial alterations of F-actin in the CA1 subfield of rat hippocampus following reperfusion after global cerebral ischemia. Phalloidin staining and confocal microscopic examination showed that F-actin disappeared from the dentritic spines in the CA1 stratum radiatum, but aggregated into thread- or fiber-like structures on days 1.5-2 after ischemia. This was followed by a nearly complete loss of F-actin in the CA1 subfield on days 3-7 after ischemia. Colocalization analysis demonstrated that the F-actin threads or fibers were located mainly within the dentritic trunks. As revealed by Nissl and Fluoro-Jade B staining, the decrease of F-actin proceeded concurrently with the evolution of ischemic damage. Consistently, western blots detected a significant decrease of F-/G-actin ratio in the dissected CA1 subfield after ischemia. To our knowledge, this is the first report on the change of F-actin in the ischemic brain. Although the underlying mechanisms remain to be elucidated, our findings may provide an important structural clue for the neuronal dysfunction induced by ischemia.
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Affiliation(s)
- Chun-Yan Guo
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Jilin Province 130021, PR China
| | - Tian-Qing Xiong
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Jilin Province 130021, PR China
| | - Bai-Hong Tan
- Laboratory Teaching Center of Basic Medicine, Norman Bethune Health Science Center of Jilin University, Jilin Province 130021, PR China
| | - Yue Gui
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Jilin Province 130021, PR China
| | - Ning Ye
- Department of Geriatrics and General Medicine, The Second Hospital of Jilin University, Changchun, Jilin, PR China
| | - Shu-Lei Li
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Jilin Province 130021, PR China
| | - Yan-Chao Li
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Jilin Province 130021, PR China.
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Kovaleva TF, Maksimova NS, Zhukov IY, Pershin VI, Mukhina IV, Gainullin MR. Cofilin: Molecular and Cellular Functions and Its Role in the Functioning of the Nervous System. NEUROCHEM J+ 2019. [DOI: 10.1134/s1819712419010124] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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27
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Woo JAA, Liu T, Fang CC, Cazzaro S, Kee T, LePochat P, Yrigoin K, Penn C, Zhao X, Wang X, Liggett SB, Kang DE. Activated cofilin exacerbates tau pathology by impairing tau-mediated microtubule dynamics. Commun Biol 2019; 2:112. [PMID: 30911686 PMCID: PMC6430779 DOI: 10.1038/s42003-019-0359-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Accepted: 02/15/2019] [Indexed: 12/27/2022] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder and the most common form of dementia. While the accumulation of Aβ is pivotal to the etiology of AD, both the microtubule-associated protein tau (MAPT) and the F-actin severing protein cofilin are necessary for the deleterious effects of Aβ. However, the molecular link between tau and cofilin remains unclear. In this study, we found that cofilin competes with tau for direct microtubule binding in vitro, in cells, and in vivo, which inhibits tau-induced microtubule assembly. Genetic reduction of cofilin mitigates tauopathy and synaptic defects in Tau-P301S mice and movement deficits in tau transgenic C. elegans. The pathogenic effects of cofilin are selectively mediated by activated cofilin, as active but not inactive cofilin selectively interacts with tubulin, destabilizes microtubules, and promotes tauopathy. These results therefore indicate that activated cofilin plays an essential intermediary role in neurotoxic signaling that promotes tauopathy.
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Affiliation(s)
- Jung-A. A. Woo
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
- Department of Molecular Pharmacology and Physiology, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - Tian Liu
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
- Department of Molecular Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - Cenxiao C. Fang
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
- Department of Molecular Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - Sara Cazzaro
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
- Department of Molecular Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - Teresa Kee
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - Patrick LePochat
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
- Department of Molecular Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - Ksenia Yrigoin
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - Courtney Penn
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
- Department of Molecular Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - Xingyu Zhao
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
- Department of Molecular Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - Xinming Wang
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - Stephen B. Liggett
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
- Department of Molecular Pharmacology and Physiology, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - David E. Kang
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
- Department of Molecular Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
- James A. Haley Veteran’s Administration Hospital, Tampa, FL 33612 USA
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28
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Ahmad R. Steroidal glycoalkaloids from Solanum nigrum target cytoskeletal proteins: an in silico analysis. PeerJ 2019; 7:e6012. [PMID: 30627484 PMCID: PMC6321755 DOI: 10.7717/peerj.6012] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 10/26/2018] [Indexed: 12/03/2022] Open
Abstract
Background Solanum nigrum (black nightshade; S. nigrum), a member of family Solanaceae, has been endowed with a heterogeneous array of secondary metabolites of which the steroidal glycoalkaloids (SGAs) and steroidal saponins (SS) have vast potential to serve as anticancer agents. Since there has been much controversy regarding safety of use of glycoalkaloids as anticancer agents, this area has remained more or less unexplored. Cytoskeletal proteins like actin play an important role in maintaining cell shape, synchronizing cell division, cell motility, etc. and along with their accessory proteins may also serve as important therapeutic targets for potential anticancer candidates. In the present study, glycoalkaloids and saponins from S. nigrum were screened for their interaction and binding affinity to cytoskeletal proteins, using molecular docking. Methods Bioactivity score and Prediction of Activity Spectra for Substances (PASS) analysis were performed using softwares Molinspiration and Osiris Data Explorer respectively, to assess the feasibility of selected phytoconstituents as potential drug candidates. The results were compared with two standard reference drugs doxorubicin hydrochloride (anticancer) and tetracycline (antibiotic). Multivariate data obtained were analyzed using principal component analysis (PCA). Results Docking analysis revealed that the binding affinities of the phytoconstituents towards the target cytoskeletal proteins decreased in the order coronin>villin>ezrin>vimentin>gelsolin>thymosin>cofilin. Glycoalkaloid solasonine displayed the greatest binding affinity towards the target proteins followed by alpha-solanine whereas amongst the saponins, nigrumnin-I showed maximum binding affinity. PASS Analysis of the selected phytoconstituents revealed 1 to 3 violations of Lipinski’s parameters indicating the need for modification of their structure-activity relationship (SAR) for improvement of their bioactivity and bioavailability. Glycoalkaloids and saponins all had bioactivity scores between −5.0 and 0.0 with respect to various receptor proteins and target enzymes. Solanidine, solasodine and solamargine had positive values of druglikeness which indicated that these compounds have the potential for development into future anticancer drugs. Toxicity potential evaluation revealed that glycoalkaloids and saponins had no toxicity, tumorigenicity or irritant effect(s). SAR analysis revealed that the number, type and location of sugar or the substitution of hydroxyl group on alkaloid backbone had an effect on the activity and that the presence of α-L-rhamnopyranose sugar at C-2 was critical for a compound to exhibit anticancer activity. Conclusion The present study revealed some cytoskeletal target(s) for S. nigrum phytoconstituents by docking analysis that have not been previously reported and thus warrant further investigations both in vitro and in vivo.
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Affiliation(s)
- Rumana Ahmad
- Department of Biochemisty, Era's Lucknow Medical College and Hospital, Era University, Lucknow, Uttar Pradesh, India
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Brás IC, Lopes LV, Outeiro TF. Sensing α-Synuclein From the Outside via the Prion Protein: Implications for Neurodegeneration. Mov Disord 2018; 33:1675-1684. [DOI: 10.1002/mds.27478] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 07/24/2018] [Accepted: 07/26/2018] [Indexed: 12/30/2022] Open
Affiliation(s)
- Inês Caldeira Brás
- Department of Experimental Neurodegeneration, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, Center for Biostructural Imaging of Neurodegeneration; University Medical Center Göttingen; Göttingen Germany
| | - Luísa V. Lopes
- Instituto de Medicina Molecular, Faculdade de Medicina; Universidade de Lisboa; Lisboa Portugal
| | - Tiago Fleming Outeiro
- Department of Experimental Neurodegeneration, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, Center for Biostructural Imaging of Neurodegeneration; University Medical Center Göttingen; Göttingen Germany
- CEDOC, Chronic Diseases Research Center, NOVA Medical School
- Faculdade de Ciências Médicas; Universidade Nova de Lisboa, Campo dos Mártires da Pátria; Lisboa Portugal
- Max Planck Institute for Experimental Medicine; Göttingen Germany
- Institute of Neuroscience, The Medical School; Newcastle University; Newcastle Upon Tyne UK
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30
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Won SJ, Minnella AM, Wu L, Eun CH, Rome E, Herson PS, Shaw AE, Bamburg JR, Swanson RA. Cofilin-actin rod formation in neuronal processes after brain ischemia. PLoS One 2018; 13:e0198709. [PMID: 30325927 PMCID: PMC6191105 DOI: 10.1371/journal.pone.0198709] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 10/03/2018] [Indexed: 12/19/2022] Open
Abstract
Functional impairment after brain ischemia results in part from loss of neuronal spines and dendrites, independent of neuronal death. Cofilin-actin rods are covalently linked aggregates of cofilin-1 and actin that form in neuronal processes (neurites) under conditions of ATP depletion and oxidative stress, and which cause neurite degeneration if not disassembled. ATP depletion and oxidative stress occur with differing severity, duration, and time course in different ischemic conditions. Here we evaluated four mouse models of brain ischemia to define the conditions that drive formation of cofilin-actin rods. Three of the models provide early reperfusion: transient middle cerebral artery occlusion (MCAo), transient bilateral common carotid artery occlusion (CCAo), and cardiac arrest / cardiopulmonary resuscitation (CA/CPR). Early reperfusion restores ATP generating capacity, but also induces oxidative stress. The fourth model, photothrombotic cortical infarction, does not provide reperfusion. Cofilin-actin rods were formed in each of these models, but with differing patterns. Where acute reperfusion occurred, rod formation was maximal within 4 hours after reperfusion. Where infarction occurred, rods continued to form for at least 24 hours after ischemic onset, and extended into the adjacent non-ischemic tissue. Interventions that limit cofilin-actin rod formation may help to preserve integrity of neuronal processes in permanent ischemia.
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Affiliation(s)
- Seok Joon Won
- Dept. of Neurology, University of California San Francisco and San Francisco Veterans Affairs Medical Center, San Francisco, CA, United States of America
| | - Angela M. Minnella
- Dept. of Neurology, University of California San Francisco and San Francisco Veterans Affairs Medical Center, San Francisco, CA, United States of America
| | - Long Wu
- Dept. of Neurology, University of California San Francisco and San Francisco Veterans Affairs Medical Center, San Francisco, CA, United States of America
| | - Claire H. Eun
- Dept. of Neurology, University of California San Francisco and San Francisco Veterans Affairs Medical Center, San Francisco, CA, United States of America
| | - Eric Rome
- Dept. of Neurology, University of California San Francisco and San Francisco Veterans Affairs Medical Center, San Francisco, CA, United States of America
| | - Paco S. Herson
- Neuronal Injury Program, Department of Anesthesiology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States of America
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States of America
| | - Alisa E. Shaw
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, United States of America
| | - James R. Bamburg
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, United States of America
| | - Raymond A. Swanson
- Dept. of Neurology, University of California San Francisco and San Francisco Veterans Affairs Medical Center, San Francisco, CA, United States of America
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31
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Rademacher S, Verheijen BM, Hensel N, Peters M, Bora G, Brandes G, Vieira de Sá R, Heidrich N, Fischer S, Brinkmann H, van der Pol WL, Wirth B, Pasterkamp RJ, Claus P. Metalloprotease-mediated cleavage of PlexinD1 and its sequestration to actin rods in the motoneuron disease spinal muscular atrophy (SMA). Hum Mol Genet 2018; 26:3946-3959. [PMID: 29016853 DOI: 10.1093/hmg/ddx282] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 07/11/2017] [Indexed: 12/12/2022] Open
Abstract
Cytoskeletal rearrangement during axon growth is mediated by guidance receptors and their ligands which act either as repellent, attractant or both. Regulation of the actin cytoskeleton is disturbed in Spinal Muscular Atrophy (SMA), a devastating neurodegenerative disease affecting mainly motoneurons, but receptor-ligand interactions leading to the dysregulation causing SMA are poorly understood. In this study, we analysed the role of the guidance receptor PlexinD1 in SMA pathogenesis. We showed that PlexinD1 is cleaved by metalloproteases in SMA and that this cleavage switches its function from an attractant to repellent. Moreover, we found that the PlexinD1 cleavage product binds to actin rods, pathological aggregate-like structures which had so far been described for age-related neurodegenerative diseases. Our data suggest a novel disease mechanism for SMA involving formation of actin rods as a molecular sink for a cleaved PlexinD1 fragment leading to dysregulation of receptor signaling.
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Affiliation(s)
- Sebastian Rademacher
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, 30625 Hannover, Germany.,Center for Systems Neuroscience (ZSN), Hannover, Germany
| | - Bert M Verheijen
- Department of Translational Neuroscience & MIND Facility, Brain Center Rudolf Magnus, University Medical Center Utrecht, 3584 CG Utrecht, The Netherlands.,Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, University Medical Center Utrecht, 3508 GA Utrecht, The Netherlands
| | - Niko Hensel
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, 30625 Hannover, Germany
| | - Miriam Peters
- Institute of Human Genetics, Center for Molecular Medicine Cologne, Center for Rare Diseases Cologne, and Institute of Genetics, University of Cologne, 50931 Cologne, Germany
| | - Gamze Bora
- Department of Medical Biology, Faculty of Medicine, Hacettepe University, 06100 Ankara, Turkey
| | - Gudrun Brandes
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, 30625 Hannover, Germany
| | - Renata Vieira de Sá
- Department of Translational Neuroscience & MIND Facility, Brain Center Rudolf Magnus, University Medical Center Utrecht, 3584 CG Utrecht, The Netherlands
| | - Natascha Heidrich
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, 30625 Hannover, Germany
| | - Silke Fischer
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, 30625 Hannover, Germany
| | - Hella Brinkmann
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, 30625 Hannover, Germany
| | - W Ludo van der Pol
- Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, University Medical Center Utrecht, 3508 GA Utrecht, The Netherlands
| | - Brunhilde Wirth
- Institute of Human Genetics, Center for Molecular Medicine Cologne, Center for Rare Diseases Cologne, and Institute of Genetics, University of Cologne, 50931 Cologne, Germany
| | - R Jeroen Pasterkamp
- Department of Translational Neuroscience & MIND Facility, Brain Center Rudolf Magnus, University Medical Center Utrecht, 3584 CG Utrecht, The Netherlands
| | - Peter Claus
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, 30625 Hannover, Germany.,Niedersachsen-Research Network on Neuroinfectiology (N-RENNT), Germany.,Center for Systems Neuroscience (ZSN), Hannover, Germany
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Fixman BB, Babcock IW, Minamide LS, Shaw AE, Oliveira da Silva MI, Runyan AM, Maloney MT, Field JJ, Bamburg JR. Modified Roller Tube Method for Precisely Localized and Repetitive Intermittent Imaging During Long-term Culture of Brain Slices in an Enclosed System. J Vis Exp 2017. [PMID: 29364208 DOI: 10.3791/56436] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Cultured rodent brain slices are useful for studying the cellular and molecular behavior of neurons and glia in an environment that maintains many of their normal in vivo interactions. Slices obtained from a variety of transgenic mouse lines or use of viral vectors for expression of fluorescently tagged proteins or reporters in wild type brain slices allow for high-resolution imaging by fluorescence microscopy. Although several methods have been developed for imaging brain slices, combining slice culture with the ability to perform repetitive high-resolution imaging of specific cells in live slices over long time periods has posed problems. This is especially true when viral vectors are used for expression of exogenous proteins since this is best done in a closed system to protect users and prevent cross contamination. Simple modifications made to the roller tube brain slice culture method that allow for repetitive high-resolution imaging of slices over many weeks in an enclosed system are reported. Culturing slices on photoetched coverslips permits the use of fiducial marks to rapidly and precisely reposition the stage to image the identical field over time before and after different treatments. Examples are shown for the use of this method combined with specific neuronal staining and expression to observe changes in hippocampal slice architecture, viral-mediated neuronal expression of fluorescent proteins, and the development of cofilin pathology, which was previously observed in the hippocampus of Alzheimer's disease (AD) in response to slice treatment with oligomers of amyloid-β (Aβ) peptide.
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Affiliation(s)
- Benjamin B Fixman
- Department of Biochemistry and Molecular Biology and Molecular, Cellular and Integrated Neuroscience Program, Colorado State University
| | - Isaac W Babcock
- Department of Biochemistry and Molecular Biology and Molecular, Cellular and Integrated Neuroscience Program, Colorado State University
| | - Laurie S Minamide
- Department of Biochemistry and Molecular Biology and Molecular, Cellular and Integrated Neuroscience Program, Colorado State University
| | - Alisa E Shaw
- Department of Biochemistry and Molecular Biology and Molecular, Cellular and Integrated Neuroscience Program, Colorado State University
| | - Marina I Oliveira da Silva
- Department of Biochemistry and Molecular Biology and Molecular, Cellular and Integrated Neuroscience Program, Colorado State University; IBMC-Instituto de Biologia Molecular e Celular, i3S-Instituto de Investigaçãoe Inovação em Saúde, ICBAS, Universidade do Porto
| | - Avery M Runyan
- Department of Biochemistry and Molecular Biology and Molecular, Cellular and Integrated Neuroscience Program, Colorado State University
| | - Michael T Maloney
- Department of Biochemistry and Molecular Biology and Molecular, Cellular and Integrated Neuroscience Program, Colorado State University; Denali Therapeutics
| | - Jeffrey J Field
- Department of Biochemistry and Molecular Biology and Molecular, Cellular and Integrated Neuroscience Program, Colorado State University
| | - James R Bamburg
- Department of Biochemistry and Molecular Biology and Molecular, Cellular and Integrated Neuroscience Program, Colorado State University;
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Functions of actin-interacting protein 1 (AIP1)/WD repeat protein 1 (WDR1) in actin filament dynamics and cytoskeletal regulation. Biochem Biophys Res Commun 2017; 506:315-322. [PMID: 29056508 DOI: 10.1016/j.bbrc.2017.10.096] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2017] [Accepted: 10/18/2017] [Indexed: 02/04/2023]
Abstract
Actin-depolymerizing factor (ADF)/cofilin and actin-interacting protein 1 (AIP1), also known as WD-repeat protein 1 (WDR1), are conserved among eukaryotes and play critical roles in dynamic reorganization of the actin cytoskeleton. AIP1 preferentially promotes disassembly of ADF/cofilin-decorated actin filaments but exhibits minimal effects on bare actin filaments. Therefore, AIP1 has been often considered to be an ancillary co-factor of ADF/cofilin that merely boosts ADF/cofilin activity level. However, genetic and cell biological studies show that AIP1 deficiency often causes lethality or severe abnormalities in multiple tissues and organs including muscle, epithelia, and blood, suggesting that AIP1 is a major regulator of many biological processes that depend on actin dynamics. This review summarizes recent progress in studies on the biochemical mechanism of actin filament severing by AIP1 and in vivo functions of AIP1 in model organisms and human diseases.
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Dugbartey GJ, Hardenberg MC, Kok WF, Boerema AS, Carey HV, Staples JF, Henning RH, Bouma HR. Renal Mitochondrial Response to Low Temperature in Non-Hibernating and Hibernating Species. Antioxid Redox Signal 2017; 27:599-617. [PMID: 28322600 DOI: 10.1089/ars.2016.6705] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
SIGNIFICANCE Therapeutic hypothermia is commonly applied to limit ischemic injury in organ transplantation, during cardiac and brain surgery and after cardiopulmonary resuscitation. In these procedures, the kidneys are particularly at risk for ischemia/reperfusion injury (IRI), likely due to their high rate of metabolism. Although hypothermia mitigates ischemic kidney injury, it is not a panacea. Residual mitochondrial failure is believed to be a key event triggering loss of cellular homeostasis, and potentially cell death. Subsequent rewarming generates large amounts of reactive oxygen species that aggravate organ injury. Recent Advances: Hibernators are able to withstand periods of profoundly reduced metabolism and body temperature ("torpor"), interspersed by brief periods of rewarming ("arousal") without signs of organ injury. Specific adaptations allow maintenance of mitochondrial homeostasis, limit oxidative stress, and protect against cell death. These adaptations consist of active suppression of mitochondrial function and upregulation of anti-oxidant enzymes and anti-apoptotic pathways. CRITICAL ISSUES Unraveling the precise molecular mechanisms that allow hibernators to cycle through torpor and arousal without precipitating organ injury may translate into novel pharmacological approaches to limit IRI in patients. FUTURE DIRECTIONS Although the precise signaling routes involved in natural hibernation are not yet fully understood, torpor-like hypothermic states with increased resistance to ischemia/reperfusion can be induced pharmacologically by 5'-adenosine monophosphate (5'-AMP), adenosine, and hydrogen sulfide (H2S) in non-hibernators. In this review, we compare the molecular effects of hypothermia in non-hibernators with natural and pharmacologically induced torpor, to delineate how safe and reversible metabolic suppression may provide resistance to renal IRI. Antioxid. Redox Signal. 27, 599-617.
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Affiliation(s)
- George J Dugbartey
- 1 Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen , Groningen, the Netherlands .,2 Division of Cardiology, Cincinnati Children's Hospital Medical Center , Cincinnati, Ohio
| | - Maarten C Hardenberg
- 1 Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen , Groningen, the Netherlands
| | - Wendelinde F Kok
- 1 Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen , Groningen, the Netherlands
| | - Ate S Boerema
- 3 Groningen Institute for Evolutionary Life Sciences, University of Groningen , Groningen, the Netherlands .,4 Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen , Groningen, the Netherlands
| | - Hannah V Carey
- 5 Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin , Madison, Wisconsin
| | - James F Staples
- 6 Department of Biology, University of Western Ontario , London, Canada
| | - Robert H Henning
- 1 Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen , Groningen, the Netherlands
| | - Hjalmar R Bouma
- 1 Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen , Groningen, the Netherlands .,7 Department of Internal Medicine, University Medical Center Groningen, University of Groningen , Groningen, the Netherlands
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35
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Ishikawa-Ankerhold HC, Daszkiewicz W, Schleicher M, Müller-Taubenberger A. Actin-Interacting Protein 1 Contributes to Intranuclear Rod Assembly in Dictyostelium discoideum. Sci Rep 2017; 7:40310. [PMID: 28074884 PMCID: PMC5225641 DOI: 10.1038/srep40310] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 12/02/2016] [Indexed: 12/21/2022] Open
Abstract
Intranuclear rods are aggregates consisting of actin and cofilin that are formed in the nucleus in consequence of chemical or mechanical stress conditions. The formation of rods is implicated in a variety of pathological conditions, such as certain myopathies and some neurological disorders. It is still not well understood what exactly triggers the formation of intranuclear rods, whether other proteins are involved, and what the underlying mechanisms of rod assembly or disassembly are. In this study, Dictyostelium discoideum was used to examine appearance, stages of assembly, composition, stability, and dismantling of rods. Our data show that intranuclear rods, in addition to actin and cofilin, are composed of a distinct set of other proteins comprising actin-interacting protein 1 (Aip1), coronin (CorA), filactin (Fia), and the 34 kDa actin-bundling protein B (AbpB). A finely tuned spatio-temporal pattern of protein recruitment was found during formation of rods. Aip1 is important for the final state of rod compaction indicating that Aip1 plays a major role in shaping the intranuclear rods. In the absence of both Aip1 and CorA, rods are not formed in the nucleus, suggesting that a sufficient supply of monomeric actin is a prerequisite for rod formation.
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Affiliation(s)
| | - Wioleta Daszkiewicz
- Department of Cell Biology (Anatomy III), Biomedical Center, LMU Munich, 82152 Planegg-Martinsried, Germany
| | - Michael Schleicher
- Department of Cell Biology (Anatomy III), Biomedical Center, LMU Munich, 82152 Planegg-Martinsried, Germany
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Abstract
The actin depolymerizing factor (ADF)/cofilin family comprises small actin-binding proteins with crucial roles in development, tissue homeostasis and disease. They are best known for their roles in regulating actin dynamics by promoting actin treadmilling and thereby driving membrane protrusion and cell motility. However, recent discoveries have increased our understanding of the functions of these proteins beyond their well-characterized roles. This Cell Science at a Glance article and the accompanying poster serve as an introduction to the diverse roles of the ADF/cofilin family in cells. The first part of the article summarizes their actions in actin treadmilling and the main mechanisms for their intracellular regulation; the second part aims to provide an outline of the emerging cellular roles attributed to the ADF/cofilin family, besides their actions in actin turnover. The latter part discusses an array of diverse processes, which include regulation of intracellular contractility, maintenance of nuclear integrity, transcriptional regulation, nuclear actin monomer transfer, apoptosis and lipid metabolism. Some of these could, of course, be indirect consequences of actin treadmilling functions, and this is discussed.
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Affiliation(s)
- Georgios Kanellos
- Edinburgh Cancer Research UK Centre, Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road South, Edinburgh EH4 2XR, UK
| | - Margaret C Frame
- Edinburgh Cancer Research UK Centre, Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road South, Edinburgh EH4 2XR, UK
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Munder MC, Midtvedt D, Franzmann T, Nüske E, Otto O, Herbig M, Ulbricht E, Müller P, Taubenberger A, Maharana S, Malinovska L, Richter D, Guck J, Zaburdaev V, Alberti S. A pH-driven transition of the cytoplasm from a fluid- to a solid-like state promotes entry into dormancy. eLife 2016; 5. [PMID: 27003292 PMCID: PMC4850707 DOI: 10.7554/elife.09347] [Citation(s) in RCA: 277] [Impact Index Per Article: 34.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 02/13/2016] [Indexed: 01/19/2023] Open
Abstract
Cells can enter into a dormant state when faced with unfavorable conditions. However, how cells enter into and recover from this state is still poorly understood. Here, we study dormancy in different eukaryotic organisms and find it to be associated with a significant decrease in the mobility of organelles and foreign tracer particles. We show that this reduced mobility is caused by an influx of protons and a marked acidification of the cytoplasm, which leads to widespread macromolecular assembly of proteins and triggers a transition of the cytoplasm to a solid-like state with increased mechanical stability. We further demonstrate that this transition is required for cellular survival under conditions of starvation. Our findings have broad implications for understanding alternative physiological states, such as quiescence and dormancy, and create a new view of the cytoplasm as an adaptable fluid that can reversibly transition into a protective solid-like state.
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Affiliation(s)
| | - Daniel Midtvedt
- Max Planck Institute for the Physics of Complex Systems, Dresden, Germany
| | - Titus Franzmann
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Elisabeth Nüske
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Oliver Otto
- Biotechnology Center, Technische Universität Dresden, Dresden, Germany
| | - Maik Herbig
- Biotechnology Center, Technische Universität Dresden, Dresden, Germany
| | - Elke Ulbricht
- Biotechnology Center, Technische Universität Dresden, Dresden, Germany
| | - Paul Müller
- Biotechnology Center, Technische Universität Dresden, Dresden, Germany
| | - Anna Taubenberger
- Biotechnology Center, Technische Universität Dresden, Dresden, Germany
| | - Shovamayee Maharana
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Liliana Malinovska
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Doris Richter
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Jochen Guck
- Biotechnology Center, Technische Universität Dresden, Dresden, Germany
| | - Vasily Zaburdaev
- Max Planck Institute for the Physics of Complex Systems, Dresden, Germany
| | - Simon Alberti
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
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38
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Bamburg JR, Bernstein BW. Actin dynamics and cofilin-actin rods in alzheimer disease. Cytoskeleton (Hoboken) 2016; 73:477-97. [PMID: 26873625 DOI: 10.1002/cm.21282] [Citation(s) in RCA: 118] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Revised: 02/04/2016] [Accepted: 02/05/2016] [Indexed: 12/18/2022]
Abstract
Cytoskeletal abnormalities and synaptic loss, typical of both familial and sporadic Alzheimer disease (AD), are induced by diverse stresses such as neuroinflammation, oxidative stress, and energetic stress, each of which may be initiated or enhanced by proinflammatory cytokines or amyloid-β (Aβ) peptides. Extracellular Aβ-containing plaques and intracellular phospho-tau-containing neurofibrillary tangles are postmortem pathologies required to confirm AD and have been the focus of most studies. However, AD brain, but not normal brain, also have increased levels of cytoplasmic rod-shaped bundles of filaments composed of ADF/cofilin-actin in a 1:1 complex (rods). Cofilin, the major ADF/cofilin isoform in mammalian neurons, severs actin filaments at low cofilin/actin ratios and stabilizes filaments at high cofilin/actin ratios. It binds cooperatively to ADP-actin subunits in F-actin. Cofilin is activated by dephosphorylation and may be oxidized in stressed neurons to form disulfide-linked dimers, required for bundling cofilin-actin filaments into stable rods. Rods form within neurites causing synaptic dysfunction by sequestering cofilin, disrupting normal actin dynamics, blocking transport, and exacerbating mitochondrial membrane potential loss. Aβ and proinflammatory cytokines induce rods through a cellular prion protein-dependent activation of NADPH oxidase and production of reactive oxygen species. Here we review recent advances in our understanding of cofilin biochemistry, rod formation, and the development of cognitive deficits. We will then discuss rod formation as a molecular pathway for synapse loss that may be common between all three prominent current AD hypotheses, thus making rods an attractive therapeutic target. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- James R Bamburg
- Department of Biochemistry and Molecular Biology and the Molecular, Cellular and Integrative Neuroscience Program, Colorado State University, Fort Collins, CO.
| | - Barbara W Bernstein
- Department of Biochemistry and Molecular Biology and the Molecular, Cellular and Integrative Neuroscience Program, Colorado State University, Fort Collins, CO
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Chai X, Zhao S, Fan L, Zhang W, Lu X, Shao H, Wang S, Song L, Failla AV, Zobiak B, Mannherz HG, Frotscher M. Reelin and cofilin cooperate during the migration of cortical neurons: a quantitative morphological analysis. Development 2016; 143:1029-40. [PMID: 26893343 DOI: 10.1242/dev.134163] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 01/29/2016] [Indexed: 12/19/2022]
Abstract
In reeler mutant mice, which are deficient in reelin (Reln), the lamination of the cerebral cortex is disrupted. Reelin signaling induces phosphorylation of LIM kinase 1, which phosphorylates the actin-depolymerizing protein cofilin in migrating neurons. Conditional cofilin mutants show neuronal migration defects. Thus, both reelin and cofilin are indispensable during cortical development. To analyze the effects of cofilin phosphorylation on neuronal migration we used in utero electroporation to transfect E14.5 wild-type cortical neurons with pCAG-EGFP plasmids encoding either a nonphosphorylatable form of cofilin 1 (cofilin(S3A)), a pseudophosphorylated form (cofilin(S3E)) or wild-type cofilin 1 (cofilin(WT)). Wild-type controls and reeler neurons were transfected with pCAG-EGFP. Real-time microscopy and histological analyses revealed that overexpression of cofilin(WT) and both phosphomutants induced migration defects and morphological abnormalities of cortical neurons. Of note, reeler neurons and cofilin(S3A)- and cofilin(S3E)-transfected neurons showed aberrant backward migration towards the ventricular zone. Overexpression of cofilin(S3E), the pseudophosphorylated form, partially rescued the migration defect of reeler neurons, as did overexpression of Limk1. Collectively, the results indicate that reelin and cofilin cooperate in controlling cytoskeletal dynamics during neuronal migration.
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Affiliation(s)
- Xuejun Chai
- Institute for Structural Neurobiology, Center for Molecular Neurobiology Hamburg (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Shanting Zhao
- Institute for Structural Neurobiology, Center for Molecular Neurobiology Hamburg (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany College of Veterinary Medicine, Northwest A&F University, 712100 Yangling, People's Republic of China
| | - Li Fan
- Institute of Zoology, School of Life Science, Lanzhou University, 730000 Lanzhou, People's Republic of China
| | - Wei Zhang
- College of Veterinary Medicine, Northwest A&F University, 712100 Yangling, People's Republic of China
| | - Xi Lu
- College of Veterinary Medicine, Northwest A&F University, 712100 Yangling, People's Republic of China
| | - Hong Shao
- Institute of Zoology, School of Life Science, Lanzhou University, 730000 Lanzhou, People's Republic of China
| | - Shaobo Wang
- Institute for Structural Neurobiology, Center for Molecular Neurobiology Hamburg (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Lingzhen Song
- Institute for Structural Neurobiology, Center for Molecular Neurobiology Hamburg (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Antonio Virgilio Failla
- UKE Microscopy Imaging Facility (UMIF), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Bernd Zobiak
- UKE Microscopy Imaging Facility (UMIF), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Hans G Mannherz
- Institute of Anatomy and Molecular Embryology, Ruhr University Bochum, 44780 Bochum, Germany
| | - Michael Frotscher
- Institute for Structural Neurobiology, Center for Molecular Neurobiology Hamburg (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
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40
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Chronophin is a glial tumor modifier involved in the regulation of glioblastoma growth and invasiveness. Oncogene 2015; 35:3163-77. [DOI: 10.1038/onc.2015.376] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 07/30/2015] [Accepted: 09/04/2015] [Indexed: 02/02/2023]
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The Stationary-Phase Cells of Saccharomyces cerevisiae Display Dynamic Actin Filaments Required for Processes Extending Chronological Life Span. Mol Cell Biol 2015; 35:3892-908. [PMID: 26351139 DOI: 10.1128/mcb.00811-15] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 08/31/2015] [Indexed: 11/20/2022] Open
Abstract
Stationary-growth-phase Saccharomyces cerevisiae yeast cultures consist of nondividing cells that undergo chronological aging. For their successful survival, the turnover of proteins and organelles, ensured by autophagy and the activation of mitochondria, is performed. Some of these processes are engaged in by the actin cytoskeleton. In S. cerevisiae stationary-phase cells, F actin has been shown to form static aggregates named actin bodies, subsequently cited to be markers of quiescence. Our in vivo analyses revealed that stationary-phase cultures contain cells with dynamic actin filaments, besides the cells with static actin bodies. The cells with dynamic actin displayed active endocytosis and autophagy and well-developed mitochondrial networks. Even more, stationary-phase cell cultures grown under calorie restriction predominantly contained cells with actin cables, confirming that the presence of actin cables is linked to successful adaptation to stationary phase. Cells with actin bodies were inactive in endocytosis and autophagy and displayed aberrations in mitochondrial networks. Notably, cells of the respiratory activity-deficient cox4Δ strain displayed the same mitochondrial aberrations and actin bodies only. Additionally, our results indicate that mitochondrial dysfunction precedes the formation of actin bodies and the appearance of actin bodies corresponds to decreased cell fitness. We conclude that the F-actin status reflects the extent of damage that arises from exponential growth.
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42
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Synergistic action of dendritic mitochondria and creatine kinase maintains ATP homeostasis and actin dynamics in growing neuronal dendrites. J Neurosci 2015; 35:5707-23. [PMID: 25855183 DOI: 10.1523/jneurosci.4115-14.2015] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The distribution of mitochondria within mature, differentiated neurons is clearly adapted to their regional physiological needs and can be perturbed under various pathological conditions, but the function of mitochondria in developing neurons has been less well studied. We have studied mitochondrial distribution within developing mouse cerebellar Purkinje cells and have found that active delivery of mitochondria into their dendrites is a prerequisite for proper dendritic outgrowth. Even when mitochondria in the Purkinje cell bodies are functioning normally, interrupting the transport of mitochondria into their dendrites severely disturbs dendritic growth. Additionally, we find that the growth of atrophic dendrites lacking mitochondria can be rescued by activating ATP-phosphocreatine exchange mediated by creatine kinase (CK). Conversely, inhibiting cytosolic CKs decreases dendritic ATP levels and also disrupts dendrite development. Mechanistically, this energy depletion appears to perturb normal actin dynamics and enhance the aggregation of cofilin within growing dendrites, reminiscent of what occurs in neurons overexpressing the dephosphorylated form of cofilin. These results suggest that local ATP synthesis by dendritic mitochondria and ATP-phosphocreatine exchange act synergistically to sustain the cytoskeletal dynamics necessary for dendritic development.
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George J, Soares C, Montersino A, Beique JC, Thomas GM. Palmitoylation of LIM Kinase-1 ensures spine-specific actin polymerization and morphological plasticity. eLife 2015; 4:e06327. [PMID: 25884247 PMCID: PMC4429338 DOI: 10.7554/elife.06327] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2015] [Accepted: 04/16/2015] [Indexed: 12/04/2022] Open
Abstract
Precise regulation of the dendritic spine actin cytoskeleton is critical for neurodevelopment and neuronal plasticity, but how neurons spatially control actin dynamics is not well defined. Here, we identify direct palmitoylation of the actin regulator LIM kinase-1 (LIMK1) as a novel mechanism to control spine-specific actin dynamics. A conserved palmitoyl-motif is necessary and sufficient to target LIMK1 to spines and to anchor LIMK1 in spines. ShRNA knockdown/rescue experiments reveal that LIMK1 palmitoylation is essential for normal spine actin polymerization, for spine-specific structural plasticity and for long-term spine stability. Palmitoylation is critical for LIMK1 function because this modification not only controls LIMK1 targeting, but is also essential for LIMK1 activation by its membrane-localized upstream activator PAK. These novel roles for palmitoylation in the spatial control of actin dynamics and kinase signaling provide new insights into structural plasticity mechanisms and strengthen links between dendritic spine impairments and neuropathological conditions. DOI:http://dx.doi.org/10.7554/eLife.06327.001 Neurons transmit information from one cell to the next by passing signals across junctions called synapses. For the neurons that receive these signals, these junctions are found on fine branch-like structures called dendrites that stick out of the cell. Dendrites themselves are decorated with smaller structures called dendritic spines, which typically receive information from one other neuron via a single synapse. Dendritic spines form in response to the signaling activity of the neuron, and problems with forming these spines have been linked to conditions such as autism and schizophrenia. Dendritic spines are created by the cell's cytoskeleton—a network of proteins that creates a constantly changing internal scaffold that shapes cells. One cytoskeleton protein called actin exists as thin filaments that can be extended or broken up by other proteins. It is not fully understood how actin is regulated in the dendritic spines. However, some researchers thought that the proteins that control the formation of the actin filaments would need to be localized to the dendritic spines to ensure that the spines form correctly. Some proteins can be made to localize to cell membranes by attaching a molecule called palmitic acid to them. Previous research has suggested that this ‘palmitoylation’ process is particularly important in neurons. Through a combination of experimental techniques, George et al. now show that palmitoylation is required to localize a protein called LIMK1, which regulates the construction of actin filaments, to the tips of dendritic spines. Further experiments showed that blocking the palmitoylation of LIMK1 alters how actin filaments form, makes spines unstable and causes synapses to be lost. George et al. also discovered that palmitoylation is necessary for LIMK1 to be activated by another protein that is found at dendritic spine membranes. This ‘dual-control’ mechanism makes it possible to precisely control where actin filaments form within dendritic spines. In addition to LIMK1, several other enzymes are also modified by palmitoylation. It will therefore be interesting to determine whether this dual control mechanism is broadly used by neurons to precisely regulate the structure and function of individual spines and synapses. DOI:http://dx.doi.org/10.7554/eLife.06327.002
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Affiliation(s)
- Joju George
- Shriners Hospitals Pediatric Research Center, Temple University School of Medicine, Philadelphia, United States
| | - Cary Soares
- Heart and Stroke Partnership for Stroke Recovery, University of Ottawa, Ottawa, Canada
| | - Audrey Montersino
- Shriners Hospitals Pediatric Research Center, Temple University School of Medicine, Philadelphia, United States
| | - Jean-Claude Beique
- Heart and Stroke Partnership for Stroke Recovery, University of Ottawa, Ottawa, Canada
| | - Gareth M Thomas
- Shriners Hospitals Pediatric Research Center, Temple University School of Medicine, Philadelphia, United States
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44
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Woo JA, Boggess T, Uhlar C, Wang X, Khan H, Cappos G, Joly-Amado A, De Narvaez E, Majid S, Minamide LS, Bamburg JR, Morgan D, Weeber E, Kang DE. RanBP9 at the intersection between cofilin and Aβ pathologies: rescue of neurodegenerative changes by RanBP9 reduction. Cell Death Dis 2015; 6:1676. [PMID: 25741591 PMCID: PMC4385917 DOI: 10.1038/cddis.2015.37] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2014] [Revised: 01/05/2015] [Accepted: 01/19/2015] [Indexed: 12/21/2022]
Abstract
Molecular pathways underlying the neurotoxicity and production of amyloid β protein (Aβ) represent potentially promising therapeutic targets for Alzheimer's disease (AD). We recently found that overexpression of the scaffolding protein RanBP9 increases Aβ production in cell lines and in transgenic mice while promoting cofilin activation and mitochondrial dysfunction. Translocation of cofilin to mitochondria and induction of cofilin–actin pathology require the activation/dephosphorylation of cofilin by Slingshot homolog 1 (SSH1) and cysteine oxidation of cofilin. In this study, we found that endogenous RanBP9 positively regulates SSH1 levels and mediates Aβ-induced translocation of cofilin to mitochondria and induction of cofilin–actin pathology in cultured cells, primary neurons, and in vivo. Endogenous level of RanBP9 was also required for Aβ-induced collapse of growth cones in immature neurons (days in vitro 9 (DIV9)) and depletion of synaptic proteins in mature neurons (DIV21). In vivo, amyloid precursor protein (APP)/presenilin-1 (PS1) mice exhibited 3.5-fold increased RanBP9 levels, and RanBP9 reduction protected against cofilin–actin pathology, synaptic damage, gliosis, and Aβ accumulation associated with APP/PS1 mice. Brains slices derived from APP/PS1 mice showed significantly impaired long-term potentiation (LTP), and RanBP9 reduction significantly enhanced paired pulse facilitation and LTP, as well as partially rescued contextual memory deficits associated with APP/PS1 mice. Therefore, these results underscore the critical importance of endogenous RanBP9 not only in Aβ accumulation but also in mediating the neurotoxic actions of Aβ at the level of synaptic plasticity, mitochondria, and cofilin–actin pathology via control of the SSH1-cofilin pathway in vivo.
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Affiliation(s)
- J A Woo
- Department of Molecular Medicine, USF Health Byrd Alzheimer's Institute, Tampa, FL, USA
| | - T Boggess
- Department of Molecular Medicine, USF Health Byrd Alzheimer's Institute, Tampa, FL, USA
| | - C Uhlar
- Department of Molecular Medicine, USF Health Byrd Alzheimer's Institute, Tampa, FL, USA
| | - X Wang
- Department of Molecular Pharmacology and Physiology, USF Health Byrd Alzheimer's Institute, Tampa, FL, USA
| | - H Khan
- Department of Molecular Medicine, USF Health Byrd Alzheimer's Institute, Tampa, FL, USA
| | - G Cappos
- Department of Molecular Medicine, USF Health Byrd Alzheimer's Institute, Tampa, FL, USA
| | - A Joly-Amado
- Department of Molecular Pharmacology and Physiology, USF Health Byrd Alzheimer's Institute, Tampa, FL, USA
| | - E De Narvaez
- Department of Molecular Medicine, USF Health Byrd Alzheimer's Institute, Tampa, FL, USA
| | - S Majid
- Department of Molecular Medicine, USF Health Byrd Alzheimer's Institute, Tampa, FL, USA
| | - L S Minamide
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
| | - J R Bamburg
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
| | - D Morgan
- Department of Molecular Pharmacology and Physiology, USF Health Byrd Alzheimer's Institute, Tampa, FL, USA
| | - E Weeber
- Department of Molecular Pharmacology and Physiology, USF Health Byrd Alzheimer's Institute, Tampa, FL, USA
| | - D E Kang
- Department of Molecular Medicine, USF Health Byrd Alzheimer's Institute, Tampa, FL, USA
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45
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Desouza M, Gunning PW, Stehn JR. The actin cytoskeleton as a sensor and mediator of apoptosis. BIOARCHITECTURE 2014; 2:75-87. [PMID: 22880146 PMCID: PMC3414384 DOI: 10.4161/bioa.20975] [Citation(s) in RCA: 173] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Apoptosis is an important biological process required for the removal of unwanted or damaged cells. Mounting evidence implicates the actin cytoskeleton as both a sensor and mediator of apoptosis. Studies also suggest that actin binding proteins (ABPs) significantly contribute to apoptosis and that actin dynamics play a key role in regulating apoptosis signaling. Changes in the organization of the actin cytoskeleton has been attributed to the process of malignant transformation and it is hypothesized that remodeling of the actin cytoskeleton may enable tumor cells to evade normal apoptotic signaling. This review aims to illuminate the role of the actin cytoskeleton in apoptosis by systematically analyzing how actin and ABPs regulate different apoptosis pathways and to also highlight the potential for developing novel compounds that target tumor-specific actin filaments.
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Affiliation(s)
- Melissa Desouza
- Oncology Research Unit; School of Medical Sciences; The University of New South Wales; Sydney, Australia
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46
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Abstract
A considerable part of the herpesvirus life cycle takes place in the host nucleus. While much progress has been made to understand the molecular processes required for virus replication in the nucleus, much less is known about the temporal and spatial dynamics of these events. Previous studies have suggested that nuclear capsid motility is directed and dependent on actin filaments (F-actin), possibly using a myosin-based, ATP-dependent mechanism. However, the conclusions from these studies were indirect. They either relied on the effects of F-actin depolymerizing drugs to deduce an F-actin dependency or they visualized nuclear F-actin but failed to show a direct link to capsid motility. Moreover, no direct link between nuclear capsid motility and a molecular motor has been established. In this report, we reinvestigate the involvement of F-actin in nuclear herpesvirus capsid transport. We show for representative members of all three herpesvirus subfamilies that nuclear capsid motility is not dependent on nuclear F-actin and that herpesvirus infection does not induce nuclear F-actin in primary fibroblasts. Moreover, in these cells, three F-actin-inhibiting drugs failed to effect capsid motility. Only latrunculin A treatment stalled nuclear capsids but did so by an unexpected effect: the drug induced actin rods in the nucleus. Immobile capsids accumulated around actin rods, and immunoprecipitation experiments suggested that capsid motility stopped because latrunculin-induced actin rods nonspecifically bind nuclear capsids. Interestingly, capsid motility was unaffected in cells that do not induce actin rods. Based on these data, we conclude that herpesvirus nuclear capsid motility is not dependent on F-actin. Herpesviruses are large DNA viruses whose replication is dependent on the host nucleus. However, we do not understand how key nuclear processes, including capsid assembly, genome replication, capsid packaging, and nuclear egress, are dynamically connected in space and time. Fluorescence live-cell microscopy revealed that nuclear capsids are highly mobile early in infection. Two studies suggested that this motility might be due to active myosin-based transport of capsids on nuclear F-actin. However, direct evidence for such motor-based transport is lacking. We revisited this phenomenon and found no evidence that nuclear capsid motility depended on F-actin. Our results reopen the question of how nuclear herpesvirus capsids move in the host nucleus.
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47
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Nath S, Munsie LN, Truant R. A huntingtin-mediated fast stress response halting endosomal trafficking is defective in Huntington's disease. Hum Mol Genet 2014; 24:450-62. [PMID: 25205111 DOI: 10.1093/hmg/ddu460] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Cellular stress is a normal part of the aging process and is especially relevant in neurodegenerative disease. Canonical stress responses, such as the heat shock response, activate following exposure to stress and restore proteostasis through the action of isomerases and chaperones within the cytosol. Through live-cell imaging, we demonstrate involvement of the Huntington's disease (HD) protein, huntingtin, in a rapid cell stress response that lies temporally upstream of canonical stress responses. This response is characterized by the formation of distinct cytosolic puncta and reversible localization of huntingtin to early endosomes. The formation of these puncta, which we have termed huntingtin stress bodies (HSBs), is associated with arrest of early-to-recycling and early-to-late endosomal trafficking. The critical domains for this response have been mapped to two regions of huntingtin flanking the polyglutamine tract, and we observe polyglutamine-expanded huntingtin-expressing cells to be defective in their ability to recover from this stress response. We propose that HSB formation rapidly diverts high ATP use from vesicular trafficking during stress, thus mobilizing canonical stress responses without relying on increased energy metabolism, and that restoration from this response is defective in HD.
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Affiliation(s)
- Siddharth Nath
- Department of Biochemistry and Biomedical Sciences, Michael G. DeGroote School of Medicine, Faculty of Health Sciences, McMaster University, Hamilton, ON, Canada L8N 3Z5 and
| | - Lise N Munsie
- Centre for Applied Neurogenetics, University of British Columbia, Vancouver, BC, Canada V6T 2B5
| | - Ray Truant
- Department of Biochemistry and Biomedical Sciences, Michael G. DeGroote School of Medicine, Faculty of Health Sciences, McMaster University, Hamilton, ON, Canada L8N 3Z5 and
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Petrovska I, Nüske E, Munder MC, Kulasegaran G, Malinovska L, Kroschwald S, Richter D, Fahmy K, Gibson K, Verbavatz JM, Alberti S. Filament formation by metabolic enzymes is a specific adaptation to an advanced state of cellular starvation. eLife 2014; 3:eLife.02409. [PMID: 24771766 PMCID: PMC4011332 DOI: 10.7554/elife.02409] [Citation(s) in RCA: 157] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Accepted: 04/10/2014] [Indexed: 01/20/2023] Open
Abstract
One of the key questions in biology is how the metabolism of a cell responds to changes in the environment. In budding yeast, starvation causes a drop in intracellular pH, but the functional role of this pH change is not well understood. Here, we show that the enzyme glutamine synthetase (Gln1) forms filaments at low pH and that filament formation leads to enzymatic inactivation. Filament formation by Gln1 is a highly cooperative process, strongly dependent on macromolecular crowding, and involves back-to-back stacking of cylindrical homo-decamers into filaments that associate laterally to form higher order fibrils. Other metabolic enzymes also assemble into filaments at low pH. Hence, we propose that filament formation is a general mechanism to inactivate and store key metabolic enzymes during a state of advanced cellular starvation. These findings have broad implications for understanding the interplay between nutritional stress, the metabolism and the physical organization of a cell.
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Affiliation(s)
- Ivana Petrovska
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Elisabeth Nüske
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Matthias C Munder
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | | | - Liliana Malinovska
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Sonja Kroschwald
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Doris Richter
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Karim Fahmy
- Institute of Resource Ecology, Helmholtz Institute Dresden-Rossendorf, Dresden, Germany
| | - Kimberley Gibson
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Jean-Marc Verbavatz
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Simon Alberti
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
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49
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Walsh KP, Minamide LS, Kane SJ, Shaw AE, Brown DR, Pulford B, Zabel MD, Lambeth JD, Kuhn TB, Bamburg JR. Amyloid-β and proinflammatory cytokines utilize a prion protein-dependent pathway to activate NADPH oxidase and induce cofilin-actin rods in hippocampal neurons. PLoS One 2014; 9:e95995. [PMID: 24760020 PMCID: PMC3997518 DOI: 10.1371/journal.pone.0095995] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 04/02/2014] [Indexed: 11/18/2022] Open
Abstract
Neurites of neurons under acute or chronic stress form bundles of filaments (rods) containing 1∶1 cofilin∶actin, which impair transport and synaptic function. Rods contain disulfide cross-linked cofilin and are induced by treatments resulting in oxidative stress. Rods form rapidly (5-30 min) in >80% of cultured hippocampal or cortical neurons treated with excitotoxic levels of glutamate or energy depleted (hypoxia/ischemia or mitochondrial inhibitors). In contrast, slow rod formation (50% of maximum response in ∼6 h) occurs in a subpopulation (∼20%) of hippocampal neurons upon exposure to soluble human amyloid-β dimer/trimer (Aβd/t) at subnanomolar concentrations. Here we show that proinflammatory cytokines (TNFα, IL-1β, IL-6) also induce rods at the same rate and within the same neuronal population as Aβd/t. Neurons from prion (PrP(C))-null mice form rods in response to glutamate or antimycin A, but not in response to proinflammatory cytokines or Aβd/t. Two pathways inducing rod formation were confirmed by demonstrating that NADPH-oxidase (NOX) activity is required for prion-dependent rod formation, but not for rods induced by glutamate or energy depletion. Surprisingly, overexpression of PrP(C) is by itself sufficient to induce rods in over 40% of hippocampal neurons through the NOX-dependent pathway. Persistence of PrP(C)-dependent rods requires the continuous activity of NOX. Removing inducers or inhibiting NOX activity in cells containing PrP(C)-dependent rods causes rod disappearance with a half-life of about 36 min. Cofilin-actin rods provide a mechanism for synapse loss bridging the amyloid and cytokine hypotheses for Alzheimer disease, and may explain how functionally diverse Aβ-binding membrane proteins induce synaptic dysfunction.
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Affiliation(s)
- Keifer P. Walsh
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Laurie S. Minamide
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Sarah J. Kane
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado, United States of America
- Molecular, Cellular and Integrative Neuroscience Program, Colorado State University, Fort Collins, Colorado, United States of America
| | - Alisa E. Shaw
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado, United States of America
| | - David R. Brown
- Department of Biology and Biochemistry, University of Bath, Bath, United Kingdom
| | - Bruce Pulford
- Prion Research Center, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Mark D. Zabel
- Molecular, Cellular and Integrative Neuroscience Program, Colorado State University, Fort Collins, Colorado, United States of America
- Prion Research Center, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - J. David Lambeth
- Department of Pathology, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Thomas B. Kuhn
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado, United States of America
- Department of Chemistry and Biochemistry, University of Alaska, Fairbanks, Alaska, United States of America
| | - James R. Bamburg
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado, United States of America
- Molecular, Cellular and Integrative Neuroscience Program, Colorado State University, Fort Collins, Colorado, United States of America
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Rajakylä EK, Vartiainen MK. Rho, nuclear actin, and actin-binding proteins in the regulation of transcription and gene expression. Small GTPases 2014; 5:e27539. [PMID: 24603113 DOI: 10.4161/sgtp.27539] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Actin cytoskeleton is one of the main targets of Rho GTPases, which act as molecular switches on many signaling pathways. During the past decade, actin has emerged as an important regulator of gene expression. Nuclear actin plays a key role in transcription, chromatin remodeling, and pre-mRNA processing. In addition, the "status" of the actin cytoskeleton is used as a signaling intermediate by at least the MKL1-SRF and Hippo-pathways, which culminate in the transcriptional regulation of cytoskeletal and growth-promoting genes, respectively. Rho GTPases may therefore regulate gene expression by controlling either cytoplasmic or nuclear actin dynamics. Although the regulation of nuclear actin polymerization is still poorly understood, many actin-binding proteins, which are downstream effectors of Rho, are found in the nuclear compartment. In this review, we discuss the possible mechanisms and key proteins that may mediate the transcriptional regulation by Rho GTPases through actin.
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Affiliation(s)
- Eeva Kaisa Rajakylä
- Program in Cell and Molecular Biology; Institute of Biotechnology; University of Helsinki; Helsinki, Finland
| | - Maria K Vartiainen
- Program in Cell and Molecular Biology; Institute of Biotechnology; University of Helsinki; Helsinki, Finland
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