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Malin J, Rosa-Birriel C, Hatini V. Pten, PI3K, and PtdIns(3,4,5)P 3 dynamics control pulsatile actin branching in Drosophila retina morphogenesis. Dev Cell 2024:S1534-5807(24)00203-X. [PMID: 38640926 DOI: 10.1016/j.devcel.2024.03.035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 11/28/2023] [Accepted: 03/25/2024] [Indexed: 04/21/2024]
Abstract
Epithelial remodeling of the Drosophila retina depends on the pulsatile contraction and expansion of apical contacts between the cells that form its hexagonal lattice. Phosphoinositide PI(3,4,5)P3 (PIP3) accumulates around tricellular adherens junctions (tAJs) during contact expansion and dissipates during contraction, but with unknown function. Here, we found that manipulations of Pten or PI3-kinase (PI3K) that either decreased or increased PIP3 resulted in shortened contacts and a disordered lattice, indicating a requirement for PIP3 dynamics and turnover. These phenotypes are caused by a loss of branched actin, resulting from impaired activity of the Rac1 Rho GTPase and the WAVE regulatory complex (WRC). We additionally found that during contact expansion, PI3K moves into tAJs to promote the cyclical increase of PIP3 in a spatially and temporally precise manner. Thus, dynamic control of PIP3 by Pten and PI3K governs the protrusive phase of junctional remodeling, which is essential for planar epithelial morphogenesis.
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Affiliation(s)
- Jacob Malin
- Tufts University School of Medicine, Department of Developmental, Molecular & Chemical Biology, Program in Genetics, Molecular and Cellular Biology, and Program in Pharmacology and Experimental Therapeutics, 150 Harrison Avenue, Boston, MA 02111, USA
| | - Christian Rosa-Birriel
- Tufts University School of Medicine, Department of Developmental, Molecular & Chemical Biology, Program in Genetics, Molecular and Cellular Biology, and Program in Pharmacology and Experimental Therapeutics, 150 Harrison Avenue, Boston, MA 02111, USA
| | - Victor Hatini
- Tufts University School of Medicine, Department of Developmental, Molecular & Chemical Biology, Program in Genetics, Molecular and Cellular Biology, and Program in Pharmacology and Experimental Therapeutics, 150 Harrison Avenue, Boston, MA 02111, USA.
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2
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Qiu Y, Lei C, Zeng J, Xie Y, Cao Y, Yuan Q, Su H, Zhang Z, Zhang C. Asparagine endopeptidase protects podocytes in adriamycin-induced nephropathy by regulating actin dynamics through cleaving transgelin. Mol Ther 2023; 31:3337-3354. [PMID: 37689970 PMCID: PMC10638058 DOI: 10.1016/j.ymthe.2023.09.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 08/04/2023] [Accepted: 09/06/2023] [Indexed: 09/11/2023] Open
Abstract
Focal segmental glomerulosclerosis (FSGS) is the most common glomerular disorder causing end-stage renal diseases worldwide. Central to the pathogenesis of FSGS is podocyte dysfunction, which is induced by diverse insults. However, the mechanism governing podocyte injury and repair remains largely unexplored. Asparagine endopeptidase (AEP), a lysosomal protease, regulates substrates by residue-specific cleavage or degradation. We identified the increased AEP expression in the primary proteinuria model which was induced by adriamycin (ADR) to mimic human FSGS. In vivo, global AEP knockout mice manifested increased injury-susceptibility of podocytes in ADR-induced nephropathy (ADRN). Podocyte-specific AEP knockout mice exhibited much more severe glomerular lesions and podocyte injury after ADR injection. In contrast, podocyte-specific augmentation of AEP in mice protected against ADRN. In vitro, knockdown and overexpression of AEP in human podocytes revealed the cytoprotection of AEP as a cytoskeleton regulator. Furthermore, transgelin, an actin-binding protein regulating actin dynamics, was cleaved by AEP, and, as a result, removed its actin-binding regulatory domain. The truncated transgelin regulated podocyte actin dynamics and repressed podocyte hypermotility, compared to the native full-length transgelin. Together, our data reveal a link between lysosomal protease AEP and podocyte cytoskeletal homeostasis, which suggests a potential therapeutic role for AEP in proteinuria disease.
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Affiliation(s)
- Yang Qiu
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, Hubei, China
| | - Chuntao Lei
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, Hubei, China
| | - Jieyu Zeng
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, Hubei, China
| | - Yaru Xie
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, Hubei, China
| | - Yiling Cao
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, Hubei, China
| | - Qian Yuan
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, Hubei, China
| | - Hua Su
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, Hubei, China
| | - Zhentao Zhang
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei, China
| | - Chun Zhang
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, Hubei, China.
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3
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Yiu TW, Holman SR, Kaidonis X, Graham RM, Iismaa SE. Transglutaminase 2 Facilitates Murine Wound Healing in a Strain-Dependent Manner. Int J Mol Sci 2023; 24:11475. [PMID: 37511238 PMCID: PMC10380275 DOI: 10.3390/ijms241411475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/12/2023] [Accepted: 07/12/2023] [Indexed: 07/30/2023] Open
Abstract
Transglutaminase 2 (TG2) plays a role in cellular processes that are relevant to wound healing, but to date no studies of wound healing in TG2 knockout mice have been reported. Here, using 129T2/SvEmsJ (129)- or C57BL/6 (B6)-backcrossed TG2 knockout mice, we show that TG2 facilitates murine wound healing in a strain-dependent manner. Early healing of in vivo cutaneous wounds and closure of in vitro scratch wounds in murine embryonic fibroblast (MEF) monolayers were delayed in 129, but not B6, TG2 knockouts, relative to their wild-type counterparts, with wound closure in 129 being faster than in B6 wild-types. A single dose of exogenous recombinant wild-type TG2 to 129 TG2-/- mice or MEFs immediately post-wounding accelerated wound closure. Neutrophil and monocyte recruitment to 129 cutaneous wounds was not affected by Tgm2 deletion up to 5 days post-wounding. Tgm2 mRNA and TG2 protein abundance were higher in 129 than in B6 wild-types and increased in abundance following cutaneous and scratch wounding. Tgm1 and factor XIIA (F13A) mRNA abundance increased post-wounding, but there was no compensation by TG family members in TG2-/- relative to TG2+/+ mice in either strain before or after wounding. 129 TG2+/+ MEF adhesion was greater and spreading was faster than that of B6 TG2+/+ MEFs, and was dependent on syndecan binding in the presence, but not absence, of RGD inhibition of integrin binding. Adhesion and spreading of 129, but not B6, TG2-/- MEFs was impaired relative to their wild-type counterparts and was accelerated by exogenous addition or transfection of TG2 protein or cDNA, respectively, and was independent of the transamidase or GTP-binding activity of TG2. Rho-family GTPase activation, central to cytoskeletal organization, was altered in 129 TG2-/- MEFs, with delayed RhoA and earlier Rac1 activation than in TG2+/+ MEFs. These findings indicate that the rate of wound healing is different between 129 and B6 mouse strains, correlating with TG2 abundance, and although not essential for wound healing, TG2 facilitates integrin- and syndecan-mediated RhoA- and Rac1-activation in fibroblasts to promote efficient wound contraction.
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Affiliation(s)
- Ting W. Yiu
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia; (T.W.Y.); (S.R.H.); (X.K.)
| | - Sara R. Holman
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia; (T.W.Y.); (S.R.H.); (X.K.)
| | - Xenia Kaidonis
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia; (T.W.Y.); (S.R.H.); (X.K.)
| | - Robert M. Graham
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia; (T.W.Y.); (S.R.H.); (X.K.)
- School of Clinical Medicine, UNSW Medicine and Health, University of New South Wales Sydney, Kensington, NSW 2052, Australia
| | - Siiri E. Iismaa
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia; (T.W.Y.); (S.R.H.); (X.K.)
- School of Clinical Medicine, UNSW Medicine and Health, University of New South Wales Sydney, Kensington, NSW 2052, Australia
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McLendon JM, Zhang X, Matasic DS, Kumar M, Koval OM, Grumbach IM, Sadayappan S, London B, Boudreau RL. Knockout of Sorbin And SH3 Domain Containing 2 (Sorbs2) in Cardiomyocytes Leads to Dilated Cardiomyopathy in Mice. J Am Heart Assoc 2022; 11:e025687. [PMID: 35730644 PMCID: PMC9333371 DOI: 10.1161/jaha.122.025687] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Background Sorbin and SH3 domain containing 2 (Sorbs2) protein is a cytoskeletal adaptor with an emerging role in cardiac biology and disease; yet, its potential relevance to adult‐onset cardiomyopathies remains underexplored. Sorbs2 global knockout mice display lethal arrhythmogenic cardiomyopathy; however, the causative mechanisms remain unclear. Herein, we examine Sorbs2 dysregulation in heart failure, characterize novel Sorbs2 cardiomyocyte‐specific knockout mice (Sorbs2‐cKO), and explore associations between Sorbs2 genetic variations and human cardiovascular disease. Methods and Results Bioinformatic analyses show myocardial Sorbs2 mRNA is consistently upregulated in humans with adult‐onset cardiomyopathies and in heart failure models. We generated Sorbs2‐cKO mice and report that they develop progressive systolic dysfunction and enlarged cardiac chambers, and they die with congestive heart failure at about 1 year old. After 3 months, Sorbs2‐cKO mice begin to show atrial enlargement and P‐wave anomalies, without dysregulation of action potential–associated ion channel and gap junction protein expressions. After 6 months, Sorbs2‐cKO mice exhibit impaired contractility in dobutamine‐treated hearts and skinned myofibers, without dysregulation of contractile protein expressions. From our comprehensive survey of potential mechanisms, we found that within 4 months, Sorbs2‐cKO hearts have defective microtubule polymerization and compensatory upregulation of structural cytoskeletal and adapter proteins, suggesting that this early intracellular structural remodeling is responsible for contractile dysfunction. Finally, we identified genetic variants that associate with decreased Sorbs2 expression and human cardiac phenotypes, including conduction abnormalities, atrial enlargement, and dilated cardiomyopathy, consistent with Sorbs2‐cKO mice phenotypes. Conclusions Our studies show that Sorbs2 is essential for maintaining structural integrity in cardiomyocytes, likely through strengthening the interactions between microtubules and other cytoskeletal proteins at cross‐link sites.
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Affiliation(s)
- Jared M McLendon
- Department of Internal Medicine University of Iowa Carver College of Medicine Iowa City IA.,Abboud Cardiovascular Research Center University of Iowa Carver College of Medicine Iowa City IA
| | - Xiaoming Zhang
- Department of Internal Medicine University of Iowa Carver College of Medicine Iowa City IA.,Abboud Cardiovascular Research Center University of Iowa Carver College of Medicine Iowa City IA
| | - Daniel S Matasic
- Department of Internal Medicine University of Iowa Carver College of Medicine Iowa City IA.,Department of Molecular Physiology and Biophysics University of Iowa Carver College of Medicine Iowa City IA
| | - Mohit Kumar
- Department of Pharmacology and Systems Physiology University of Cincinnati OH.,Division of Cardiovascular Health and Disease Department of Internal Medicine Heart, Lung, and Vascular Institute University of Cincinnati OH
| | - Olha M Koval
- Department of Internal Medicine University of Iowa Carver College of Medicine Iowa City IA.,Abboud Cardiovascular Research Center University of Iowa Carver College of Medicine Iowa City IA
| | - Isabella M Grumbach
- Department of Internal Medicine University of Iowa Carver College of Medicine Iowa City IA.,Abboud Cardiovascular Research Center University of Iowa Carver College of Medicine Iowa City IA
| | - Sakthivel Sadayappan
- Department of Pharmacology and Systems Physiology University of Cincinnati OH.,Division of Cardiovascular Health and Disease Department of Internal Medicine Heart, Lung, and Vascular Institute University of Cincinnati OH
| | - Barry London
- Department of Internal Medicine University of Iowa Carver College of Medicine Iowa City IA.,Abboud Cardiovascular Research Center University of Iowa Carver College of Medicine Iowa City IA
| | - Ryan L Boudreau
- Department of Internal Medicine University of Iowa Carver College of Medicine Iowa City IA.,Abboud Cardiovascular Research Center University of Iowa Carver College of Medicine Iowa City IA
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5
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Abstract
Rho family GTPases are molecular switches best known for their pivotal role in dynamic regulation of the actin cytoskeleton, but also of cellular morphology, motility, adhesion and proliferation. The prototypic members of this family (RhoA, Rac1 and Cdc42) also contribute to the normal kidney function and play important roles in the structure and function of various kidney cells including tubular epithelial cells, mesangial cells and podocytes. The kidney's vital filtration function depends on the structural integrity of the glomerulus, the proximal portion of the nephron. Within the glomerulus, the architecturally actin-based cytoskeleton podocyte forms the final cellular barrier to filtration. The glomerulus appears as a highly dynamic signalling hub that is capable of integrating intracellular cues from its individual structural components. Dynamic regulation of the podocyte cytoskeleton is required for efficient barrier function of the kidney. As master regulators of actin cytoskeletal dynamics, Rho GTPases are therefore of critical importance for sustained kidney barrier function. Dysregulated activities of the Rho GTPases and of their effectors are implicated in the pathogenesis of both hereditary and idiopathic forms of kidney diseases. Diabetic nephropathy is a progressive kidney disease that is caused by injury to kidney glomeruli. High glucose activates RhoA/Rho-kinase in mesangial cells, leading to excessive extracellular matrix production (glomerulosclerosis). This RhoA/Rho-kinase pathway also seems involved in the post-transplant hypertension frequently observed during treatment with calcineurin inhibitors, whereas Rac1 activation was observed in post-transplant ischaemic acute kidney injury.
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Affiliation(s)
- Clara Steichen
- Inserm UMR-1082 Irtomit, Poitiers, France,Faculté De Médecine Et De Pharmacie, Université De Poitiers, Poitiers, France
| | - Claude Hervé
- Inserm UMR-1082 Irtomit, Poitiers, France,CONTACT Claude HervéInserm UMR-1082 Irtomit, Poitiers, France
| | - Thierry Hauet
- Inserm UMR-1082 Irtomit, Poitiers, France,Faculté De Médecine Et De Pharmacie, Université De Poitiers, Poitiers, France,Department of Medical Biology, Service De Biochimie, CHU De Poitiers, Poitiers, France
| | - Nicolas Bourmeyster
- Faculté De Médecine Et De Pharmacie, Université De Poitiers, Poitiers, France,Department of Medical Biology, Service De Biochimie, CHU De Poitiers, Poitiers, France,Laboratoire STIM CNRS ERL 7003, Université de Poitiers, Poitiers Cédex, France
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6
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Scala M, Nishikawa M, Nagata KI, Striano P. Pathophysiological Mechanisms in Neurodevelopmental Disorders Caused by Rac GTPases Dysregulation: What's behind Neuro-RACopathies. Cells 2021; 10:3395. [PMID: 34943902 PMCID: PMC8699292 DOI: 10.3390/cells10123395] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/23/2021] [Accepted: 11/30/2021] [Indexed: 02/07/2023] Open
Abstract
Rho family guanosine triphosphatases (GTPases) regulate cellular signaling and cytoskeletal dynamics, playing a pivotal role in cell adhesion, migration, and cell cycle progression. The Rac subfamily of Rho GTPases consists of three highly homologous proteins, Rac 1-3. The proper function of Rac1 and Rac3, and their correct interaction with guanine nucleotide-exchange factors (GEFs) and GTPase-activating proteins (GAPs) are crucial for neural development. Pathogenic variants affecting these delicate biological processes are implicated in different medical conditions in humans, primarily neurodevelopmental disorders (NDDs). In addition to a direct deleterious effect produced by genetic variants in the RAC genes, a dysregulated GTPase activity resulting from an abnormal function of GEFs and GAPs has been involved in the pathogenesis of distinctive emerging conditions. In this study, we reviewed the current pertinent literature on Rac-related disorders with a primary neurological involvement, providing an overview of the current knowledge on the pathophysiological mechanisms involved in the neuro-RACopathies.
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Affiliation(s)
- Marcello Scala
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, 16132 Genoa, Italy;
- Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
| | - Masashi Nishikawa
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Developmental Disability Center, 713-8 Kamiya, Kasugai 480-0392, Japan; (M.N.); (K.-i.N.)
| | - Koh-ichi Nagata
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Developmental Disability Center, 713-8 Kamiya, Kasugai 480-0392, Japan; (M.N.); (K.-i.N.)
- Department of Neurochemistry, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Nagoya 466-8550, Japan
| | - Pasquale Striano
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, 16132 Genoa, Italy;
- Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
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7
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Dagar S, Pathak D, Oza HV, Mylavarapu SVS. Tunneling nanotubes and related structures: molecular mechanisms of formation and function. Biochem J 2021; 478:3977-98. [PMID: 34813650 DOI: 10.1042/BCJ20210077] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 10/12/2021] [Accepted: 11/01/2021] [Indexed: 12/13/2022]
Abstract
Tunneling nanotubes (TNTs) are F-actin-based, membrane-enclosed tubular connections between animal cells that transport a variety of cellular cargo. Over the last 15 years since their discovery, TNTs have come to be recognized as key players in normal cell communication and organism development, and are also exploited for the spread of various microbial pathogens and major diseases like cancer and neurodegenerative disorders. TNTs have also been proposed as modalities for disseminating therapeutic drugs between cells. Despite the rapidly expanding and wide-ranging relevance of these structures in both health and disease, there is a glaring dearth of molecular mechanistic knowledge regarding the formation and function of these important but enigmatic structures. A series of fundamental steps are essential for the formation of functional nanotubes. The spatiotemporally controlled and directed modulation of cortical actin dynamics would be required to ensure outward F-actin polymerization. Local plasma membrane deformation to impart negative curvature and membrane addition at a rate commensurate with F-actin polymerization would enable outward TNT elongation. Extrinsic tactic cues, along with cognate intrinsic signaling, would be required to guide and stabilize the elongating TNT towards its intended target, followed by membrane fusion to create a functional TNT. Selected cargoes must be transported between connected cells through the action of molecular motors, before the TNT is retracted or destroyed. This review summarizes the current understanding of the molecular mechanisms regulating these steps, also highlighting areas that deserve future attention.
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8
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Lee EHC, Wong DCP, Ding JL. NK Cells in a Tug-of-War With Cancer: The Roles of Transcription Factors and Cytoskeleton. Front Immunol 2021; 12:734551. [PMID: 34594338 PMCID: PMC8476995 DOI: 10.3389/fimmu.2021.734551] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 08/30/2021] [Indexed: 12/19/2022] Open
Abstract
Natural killer (NK) cells are innate immune cells which play a key role in shaping the immune response against cancer. Initially hailed for their potential to recognise and eliminate tumour cells, their application has been greatly hindered by the immunosuppressive tumour microenvironment (TME) which suppresses NK functions (e.g., cytotoxicity). This dysfunctional state that is accompanied by phenotypic changes such as upregulation of inhibitory receptors and downregulation of activating receptors, forms the basis of what many researchers have referred to as ‘exhausted’ NK cells. However, there is no consensus on whether these phenotypes are sufficient to define an exhausted state of the NK cell. While recent advances in checkpoint inhibition appear to show promise in early-stage pre-clinical studies, much remains to be fully explored and understood in the context of the TME. The TME is where the NK cells are subjected to interaction with various cell types and soluble factors, which could exert an inhibitory effect on NK cytotoxicity. In this review, we provide an overview of the general markers of NK cell exhaustion viz, the surface activating and inhibitory receptors. We also highlight the potential role of T-box transcription factors in characterising such a dysfunctional state and discuss the often-overlooked mechanism of cell cytoskeletal dynamics in regulating NK cell function. These aspects may further contribute to NK exhaustion or NK revival in cancer and may open new avenues to explore cancer treatment strategies.
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Affiliation(s)
- E Hui Clarissa Lee
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Darren Chen Pei Wong
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Jeak Ling Ding
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
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9
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Bernier LP, Bohlen CJ, York EM, Choi HB, Kamyabi A, Dissing-Olesen L, Hefendehl JK, Collins HY, Stevens B, Barres BA, MacVicar BA. Nanoscale Surveillance of the Brain by Microglia via cAMP-Regulated Filopodia. Cell Rep 2020; 27:2895-2908.e4. [PMID: 31167136 DOI: 10.1016/j.celrep.2019.05.010] [Citation(s) in RCA: 117] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 03/14/2019] [Accepted: 04/30/2019] [Indexed: 02/07/2023] Open
Abstract
Microglia, the brain's immune cells, maintain homeostasis and sense pathological changes by continuously surveying the parenchyma with highly motile large processes. Here, we demonstrate that microglia also use thin actin-dependent filopodia that allow fast nanoscale sensing within discrete regions. Filopodia are distinct from large processes by their size, speed, and regulation mechanism. Increasing cyclic AMP (cAMP) by activating norepinephrine Gs-coupled receptors, applying nitric oxide, or inhibiting phosphodiesterases rapidly increases filopodia but collapses large processes. Alternatively, Gi-coupled P2Y12 receptor activation collapses filopodia but triggers large processes extension with bulbous tips. Similar control of cytoskeletal dynamics and microglial morphology by cAMP is observed in ramified primary microglia, suggesting that filopodia are intrinsically generated sensing structures. Therefore, nanoscale surveillance of brain parenchyma by microglia requires localized cAMP increases that drive filopodia formation. Shifting intracellular cAMP levels controls the polarity of microglial responses to changes in brain homeostasis and alters the scale of immunosurveillance.
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Affiliation(s)
- Louis-Philippe Bernier
- University of British Columbia, Djavad Mowafaghian Centre for Brain Health, Vancouver, BC V6T 1Z3, Canada.
| | - Christopher J Bohlen
- Stanford University School of Medicine, Department of Neurobiology, Stanford, CA 94305, USA
| | - Elisa M York
- University of British Columbia, Djavad Mowafaghian Centre for Brain Health, Vancouver, BC V6T 1Z3, Canada
| | - Hyun B Choi
- University of British Columbia, Djavad Mowafaghian Centre for Brain Health, Vancouver, BC V6T 1Z3, Canada
| | - Alireza Kamyabi
- University of British Columbia, Djavad Mowafaghian Centre for Brain Health, Vancouver, BC V6T 1Z3, Canada
| | - Lasse Dissing-Olesen
- University of British Columbia, Djavad Mowafaghian Centre for Brain Health, Vancouver, BC V6T 1Z3, Canada; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School Boston, MA 02115, USA
| | - Jasmin K Hefendehl
- University of British Columbia, Djavad Mowafaghian Centre for Brain Health, Vancouver, BC V6T 1Z3, Canada
| | - Hannah Y Collins
- Stanford University School of Medicine, Department of Neurobiology, Stanford, CA 94305, USA
| | - Beth Stevens
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School Boston, MA 02115, USA
| | - Ben A Barres
- Stanford University School of Medicine, Department of Neurobiology, Stanford, CA 94305, USA
| | - Brian A MacVicar
- University of British Columbia, Djavad Mowafaghian Centre for Brain Health, Vancouver, BC V6T 1Z3, Canada.
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10
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Rodemer W, Gallo G, Selzer ME. Mechanisms of Axon Elongation Following CNS Injury: What Is Happening at the Axon Tip? Front Cell Neurosci 2020; 14:177. [PMID: 32719586 PMCID: PMC7347967 DOI: 10.3389/fncel.2020.00177] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 05/22/2020] [Indexed: 12/12/2022] Open
Abstract
After an injury to the central nervous system (CNS), functional recovery is limited by the inability of severed axons to regenerate and form functional connections with appropriate target neurons beyond the injury. Despite tremendous advances in our understanding of the mechanisms of axon growth, and of the inhibitory factors in the injured CNS that prevent it, disappointingly little progress has been made in restoring function to human patients with CNS injuries, such as spinal cord injury (SCI), through regenerative therapies. Clearly, the large number of overlapping neuron-intrinsic and -extrinsic growth-inhibitory factors attenuates the benefit of neutralizing any one target. More daunting is the distances human axons would have to regenerate to reach some threshold number of target neurons, e.g., those that occupy one complete spinal segment, compared to the distances required in most experimental models, such as mice and rats. However, the difficulties inherent in studying mechanisms of axon regeneration in the mature CNS in vivo have caused researchers to rely heavily on extrapolation from studies of axon regeneration in peripheral nerve, or of growth cone-mediated axon development in vitro and in vivo. Unfortunately, evidence from several animal models, including the transected lamprey spinal cord, has suggested important differences between regeneration of mature CNS axons and growth of axons in peripheral nerve, or during embryonic development. Specifically, long-distance regeneration of severed axons may not involve the actin-myosin molecular motors that guide embryonic growth cones in developing axons. Rather, non-growth cone-mediated axon elongation may be required to propel injured axons in the mature CNS. If so, it may be necessary to use other experimental models to promote regeneration that is sufficient to contact a critical number of target neurons distal to a CNS lesion. This review examines the cytoskeletal underpinnings of axon growth, focusing on the elongating axon tip, to gain insights into how CNS axons respond to injury, and how this might affect the development of regenerative therapies for SCI and other CNS injuries.
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Affiliation(s)
- William Rodemer
- Shriners Hospitals Pediatric Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, United States
| | - Gianluca Gallo
- Shriners Hospitals Pediatric Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, United States.,Department of Anatomy and Cell Biology, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, United States
| | - Michael E Selzer
- Shriners Hospitals Pediatric Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, United States.,Department of Neurology, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, United States
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11
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Salem FB, Bunner WP, Prabhu VV, Kuyateh AB, O'Bryant CT, Murashov AK, Szatmari EM, Hughes RM. CofActor: A light- and stress-gated optogenetic clustering tool to study disease-associated cytoskeletal dynamics in living cells. J Biol Chem 2020; 295:11231-11245. [PMID: 32424038 DOI: 10.1074/jbc.ra119.012427] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 05/12/2020] [Indexed: 11/06/2022] Open
Abstract
The hallmarks of neurodegenerative diseases, including neural fibrils, reactive oxygen species, and cofilin-actin rods, present numerous challenges in the development of in vivo diagnostic tools. Biomarkers such as β-amyloid (Aβ) fibrils and Tau tangles in Alzheimer's disease are accessible only via invasive cerebrospinal fluid assays, and reactive oxygen species can be fleeting and challenging to monitor in vivo Although remaining a challenge for in vivo detection, the protein-protein interactions underlying these disease-specific biomarkers present opportunities for the engineering of in vitro pathology-sensitive biosensors. These tools can be useful for investigating early stage events in neurodegenerative diseases in both cellular and animal models and may lead to clinically useful reagents. Here, we report a light- and cellular stress-gated protein switch based on cofilin-actin rod formation, occurring in stressed neurons in the Alzheimer's disease brain and following ischemia. By coupling the stress-sensitive cofilin-actin interaction with the light-responsive Cry2-CIB blue-light switch, referred to hereafter as the CofActor, we accomplished both light- and energetic/oxidative stress-gated control of this interaction. Site-directed mutagenesis of both cofilin and actin revealed residues critical for sustaining or abrogating the light- and stress-gated response. Of note, the switch response varied depending on whether cellular stress was generated via glycolytic inhibition or by both glycolytic inhibition and azide-induced ATP depletion. We also demonstrate light- and cellular stress-gated switch function in cultured hippocampal neurons. CofActor holds promise for the tracking of early stage events in neurodegeneration and for investigating actin's interactions with other proteins during cellular stress.
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Affiliation(s)
- Fatema B Salem
- Department of Chemistry, East Carolina University, Greenville, North Carolina, USA
| | - Wyatt P Bunner
- Department of Physical Therapy, East Carolina University, Greenville, North Carolina, USA
| | - Vishwanath V Prabhu
- Department of Physical Therapy, East Carolina University, Greenville, North Carolina, USA
| | - Abu-Bakarr Kuyateh
- Department of Chemistry, East Carolina University, Greenville, North Carolina, USA
| | - Collin T O'Bryant
- Department of Chemistry, East Carolina University, Greenville, North Carolina, USA
| | - Alexander K Murashov
- Department of Physiology, East Carolina University, Greenville, North Carolina, USA
| | - Erzsebet M Szatmari
- Department of Physical Therapy, East Carolina University, Greenville, North Carolina, USA
| | - Robert M Hughes
- Department of Chemistry, East Carolina University, Greenville, North Carolina, USA
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12
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Hu C, Kanellopoulos AK, Richter M, Petersen M, Konietzny A, Tenedini FM, Hoyer N, Cheng L, Poon CLC, Harvey KF, Windhorst S, Parrish JZ, Mikhaylova M, Bagni C, Calderon de Anda F, Soba P. Conserved Tao Kinase Activity Regulates Dendritic Arborization, Cytoskeletal Dynamics, and Sensory Function in Drosophila. J Neurosci 2020; 40:1819-1833. [PMID: 31964717 PMCID: PMC7046460 DOI: 10.1523/jneurosci.1846-19.2020] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 01/13/2020] [Accepted: 01/16/2020] [Indexed: 12/11/2022] Open
Abstract
Dendritic arborization is highly regulated and requires tight control of dendritic growth, branching, cytoskeletal dynamics, and ion channel expression to ensure proper function. Abnormal dendritic development can result in altered network connectivity, which has been linked to neurodevelopmental disorders, including autism spectrum disorders (ASDs). How neuronal growth control programs tune dendritic arborization to ensure function is still not fully understood. Using Drosophila dendritic arborization (da) neurons as a model, we identified the conserved Ste20-like kinase Tao as a negative regulator of dendritic arborization. We show that Tao kinase activity regulates cytoskeletal dynamics and sensory channel localization required for proper sensory function in both male and female flies. We further provide evidence for functional conservation of Tao kinase, showing that its ASD-linked human ortholog, Tao kinase 2 (Taok2), could replace Drosophila Tao and rescue dendritic branching, dynamic microtubule alterations, and behavioral defects. However, several ASD-linked Taok2 variants displayed impaired rescue activity, suggesting that Tao/Taok2 mutations can disrupt sensory neuron development and function. Consistently, we show that Tao kinase activity is required in developing and as well as adult stages for maintaining normal dendritic arborization and sensory function to regulate escape and social behavior. Our data suggest an important role for Tao kinase signaling in cytoskeletal organization to maintain proper dendritic arborization and sensory function, providing a strong link between developmental sensory aberrations and behavioral abnormalities relevant for Taok2-dependent ASDs.SIGNIFICANCE STATEMENT Autism spectrum disorders (ASDs) are linked to abnormal dendritic arbors. However, the mechanisms of how dendritic arbors develop to promote functional and proper behavior are unclear. We identified Drosophila Tao kinase, the ortholog of the ASD risk gene Taok2, as a regulator of dendritic arborization in sensory neurons. We show that Tao kinase regulates cytoskeletal dynamics, controls sensory ion channel localization, and is required to maintain somatosensory function in vivo Interestingly, ASD-linked human Taok2 mutations rendered it nonfunctional, whereas its WT form could restore neuronal morphology and function in Drosophila lacking endogenous Tao. Our findings provide evidence for a conserved role of Tao kinase in dendritic development and function of sensory neurons, suggesting that aberrant sensory function might be a common feature of ASDs.
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Affiliation(s)
- Chun Hu
- Neuronal Patterning and Connectivity Laboratory, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | | | - Melanie Richter
- Neuronal Development Laboratory, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Meike Petersen
- Neuronal Patterning and Connectivity Laboratory, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Anja Konietzny
- Neuronal Protein Transport Laboratory, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Federico M Tenedini
- Neuronal Patterning and Connectivity Laboratory, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Nina Hoyer
- Neuronal Patterning and Connectivity Laboratory, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Lin Cheng
- Neuronal Patterning and Connectivity Laboratory, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Carole L C Poon
- Peter MacCallum Cancer Centre, Melbourne, 3000 Victoria, Australia
| | - Kieran F Harvey
- Peter MacCallum Cancer Centre, Melbourne, 3000 Victoria, Australia
- Department of Anatomy and Developmental Biology, and Biomedicine Discovery Institute, Monash University, Clayton, 3800 Victoria, Australia
| | - Sabine Windhorst
- Center for Experimental Medicine, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Jay Z Parrish
- Department of Biology, University of Washington, Seattle, 98195 Washington, and
| | - Marina Mikhaylova
- Neuronal Protein Transport Laboratory, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Claudia Bagni
- Department of Fundamental Neurosciences, University of Lausanne, 1005 Lausanne, Switzerland
- Department of Biomedicine and Prevention, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Froylan Calderon de Anda
- Neuronal Development Laboratory, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Peter Soba
- Neuronal Patterning and Connectivity Laboratory, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany,
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13
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Godwin WC, Hoffmann GF, Gray TJ, Hughes RM. Imaging of morphological and biochemical hallmarks of apoptosis with optimized optogenetic tools. J Biol Chem 2019; 294:16918-16929. [PMID: 31582560 DOI: 10.1074/jbc.ra119.009141] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 09/27/2019] [Indexed: 01/14/2023] Open
Abstract
Creation of optogenetic switches for specific activation of cell death pathways can provide insights into apoptosis and could also form a basis for noninvasive, next-generation therapeutic strategies. Previous work has demonstrated that cryptochrome 2 (Cry2)/cryptochrome-interacting β helix-loop-helix (CIB), a blue light-activated protein-protein dimerization module from the plant Arabidopsis thaliana, together with BCL2-associated X apoptosis regulator (BAX), an outer mitochondrial membrane-targeting pro-apoptotic protein, can be used for light-mediated initiation of mitochondrial outer membrane permeabilization (MOMP) and downstream apoptosis. In this work, we further developed the original light-activated Cry2-BAX system (hereafter referred to as OptoBAX) by improving the photophysical properties and light-independent interactions of this optogenetic switch. The resulting optogenetic constructs significantly reduced the frequency of light exposure required for membrane permeabilization activation and also decreased dark-state cytotoxicity. We used OptoBAX in a series of experiments in Neuro-2a and HEK293T cells to measure the timing of the dramatic morphological and biochemical changes occurring in cells after light-induced MOMP. In these experiments, we used OptoBAX in tandem with fluorescent reporters to image key events in early apoptosis, including membrane inversion, caspase cleavage, and actin redistribution. We then used these data to construct a timeline of biochemical and morphological events in early apoptosis, demonstrating a direct link between MOMP-induced redistribution of actin and apoptosis progression. In summary, we created a next-generation Cry2/CIB-BAX system requiring less frequent light stimulation and established a timeline of critical apoptotic events, providing detailed insights into key steps in early apoptosis.
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Affiliation(s)
- Walton C Godwin
- Department of Chemistry, East Carolina University, Greenville, North Carolina 27858
| | - George F Hoffmann
- Department of Chemistry, East Carolina University, Greenville, North Carolina 27858
| | - Taylor J Gray
- Department of Biology, East Carolina University, Greenville, North Carolina 27858
| | - Robert M Hughes
- Department of Chemistry, East Carolina University, Greenville, North Carolina 27858
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14
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Abstract
Background Cardiac hypertrophy is an adaptive remodeling event that may improve or diminish contractile performance of the heart. Physiologic and pathologic hypertrophy yield distinct outcomes, yet both are dependent on caspase‐directed proteolysis. This suggests that each form of myocardial growth may derive from a specific caspase cleavage event(s). We examined whether caspase 3 cleavage of the actin capping/severing protein gelsolin is essential for the development of pathologic hypertrophy. Methods and Results Caspase targeting of gelsolin was established through protein analysis of hypertrophic cardiomyocytes and mass spectrometry mapping of cleavage sites. Pathologic agonists induced late‐stage caspase‐mediated cleavage of gelsolin. The requirement of caspase‐mediated gelsolin cleavage for hypertrophy induction was evaluated in primary cardiomyocytes by cell size analysis, monitoring of prohypertrophy markers, and measurement of hypertrophy‐related transcription activity. The in vivo impact of caspase‐mediated cleavage was investigated by echo‐guided intramyocardial injection of adenoviral‐expressed gelsolin. Expression of the N‐terminal gelsolin caspase cleavage fragment was necessary and sufficient to cause pathologic remodeling in isolated cardiomyocytes and the intact heart, whereas expression of a noncleavable form prevents cardiac remodeling. Alterations in myocardium structure and function were determined by echocardiography and end‐stage cardiomyocyte cell size analysis. Gelsolin secretion was also monitored for its impact on naïve cells using competitive antibody trapping, demonstrating that hypertrophic agonist stimulation of cardiomyocytes leads to gelsolin secretion, which induces hypertrophy in naïve cells. Conclusions These results suggest that cell autonomous caspase cleavage of gelsolin is essential for pathologic hypertrophy and that cardiomyocyte secretion of gelsolin may accelerate this negative remodeling response.
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Affiliation(s)
- Charis Putinski
- 1 Ottawa Hospital Research Institute Sprott Centre for Stem Cell Research Regenerative Medicine Program Ottawa Hospital Ottawa Ontario Canada.,2 Department of Cellular and Molecular Medicine Faculty of Medicine University of Ottawa Ontario Canada
| | - Mohammad Abdul-Ghani
- 1 Ottawa Hospital Research Institute Sprott Centre for Stem Cell Research Regenerative Medicine Program Ottawa Hospital Ottawa Ontario Canada.,2 Department of Cellular and Molecular Medicine Faculty of Medicine University of Ottawa Ontario Canada
| | - Steve Brunette
- 1 Ottawa Hospital Research Institute Sprott Centre for Stem Cell Research Regenerative Medicine Program Ottawa Hospital Ottawa Ontario Canada
| | - Patrick G Burgon
- 2 Department of Cellular and Molecular Medicine Faculty of Medicine University of Ottawa Ontario Canada.,3 Department of Medicine University of Ottawa Ontario Canada.,4 University of Ottawa Heart Institute Ottawa Ontario Canada
| | - Lynn A Megeney
- 1 Ottawa Hospital Research Institute Sprott Centre for Stem Cell Research Regenerative Medicine Program Ottawa Hospital Ottawa Ontario Canada.,2 Department of Cellular and Molecular Medicine Faculty of Medicine University of Ottawa Ontario Canada.,3 Department of Medicine University of Ottawa Ontario Canada
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15
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Nicholson CJ, Singh K, Saphirstein RJ, Gao YZ, Li Q, Chiu JG, Leavis P, Verwoert GC, Mitchell GF, Porter T, Morgan KG. Reversal of Aging-Induced Increases in Aortic Stiffness by Targeting Cytoskeletal Protein-Protein Interfaces. J Am Heart Assoc 2018; 7:JAHA.118.008926. [PMID: 30021807 PMCID: PMC6201469 DOI: 10.1161/jaha.118.008926] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Background The proximal aorta normally functions as a critical shock absorber that protects small downstream vessels from damage by pressure and flow pulsatility generated by the heart during systole. This shock absorber function is impaired with age because of aortic stiffening. Methods and Results We examined the contribution of common genetic variation to aortic stiffness in humans by interrogating results from the AortaGen Consortium genome‐wide association study of carotid‐femoral pulse wave velocity. Common genetic variation in the N‐WASP (WASL) locus is associated with carotid‐femoral pulse wave velocity (rs600420, P=0.0051). Thus, we tested the hypothesis that decoy proteins designed to disrupt the interaction of cytoskeletal proteins such as N‐WASP with its binding partners in the vascular smooth muscle cytoskeleton could decrease ex vivo stiffness of aortas from a mouse model of aging. A synthetic decoy peptide construct of N‐WASP significantly reduced activated stiffness in ex vivo aortas of aged mice. Two other cytoskeletal constructs targeted to VASP and talin‐vinculin interfaces similarly decreased aging‐induced ex vivo active stiffness by on‐target specific actions. Furthermore, packaging these decoy peptides into microbubbles enables the peptides to be ultrasound‐targeted to the wall of the proximal aorta to attenuate ex vivo active stiffness. Conclusions We conclude that decoy peptides targeted to vascular smooth muscle cytoskeletal protein‐protein interfaces and microbubble packaged can decrease aortic stiffness ex vivo. Our results provide proof of concept at the ex vivo level that decoy peptides targeted to cytoskeletal protein‐protein interfaces may lead to substantive dynamic modulation of aortic stiffness.
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Affiliation(s)
| | - Kuldeep Singh
- Department of Health Sciences, Sargent College Boston University, Boston, MA
| | | | - Yuan Z Gao
- Department of Health Sciences, Sargent College Boston University, Boston, MA
| | - Qian Li
- Department of Biomedical Engineering, Boston University, Boston, MA
| | - Joanna G Chiu
- Department of Biomedical Engineering, Boston University, Boston, MA
| | - Paul Leavis
- Department of Integrative Physiology and Pathobiology, Tufts University, Boston, MA
| | - Germaine C Verwoert
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
| | | | | | - Tyrone Porter
- Department of Biomedical Engineering, Boston University, Boston, MA.,Department of Mechanical Engineering, Boston University, Boston, MA
| | - Kathleen G Morgan
- Department of Health Sciences, Sargent College Boston University, Boston, MA
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16
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Fan L, Lu Y, Shen X, Shao H, Suo L, Wu Q. Alpha protocadherins and Pyk2 kinase regulate cortical neuron migration and cytoskeletal dynamics via Rac1 GTPase and WAVE complex in mice. eLife 2018; 7:e35242. [PMID: 29911975 PMCID: PMC6047886 DOI: 10.7554/elife.35242] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 06/11/2018] [Indexed: 02/06/2023] Open
Abstract
Diverse clustered protocadherins are thought to function in neurite morphogenesis and neuronal connectivity in the brain. Here, we report that the protocadherin alpha (Pcdha) gene cluster regulates neuronal migration during cortical development and cytoskeletal dynamics in primary cortical culture through the WAVE (Wiskott-Aldrich syndrome family verprolin homologous protein, also known as Wasf) complex. In addition, overexpression of proline-rich tyrosine kinase 2 (Pyk2, also known as Ptk2b, Cakβ, Raftk, Fak2, and Cadtk), a non-receptor cell-adhesion kinase and scaffold protein downstream of Pcdhα, impairs cortical neuron migration via inactivation of the small GTPase Rac1. Thus, we define a molecular Pcdhα/WAVE/Pyk2/Rac1 axis from protocadherin cell-surface receptors to actin cytoskeletal dynamics in cortical neuron migration and dendrite morphogenesis in mouse brain.
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Affiliation(s)
- Li Fan
- Key Laboratory of Systems Biomedicine (Ministry of Education), Center for Comparative Biomedicine, Institute of Systems Biomedicine, Shanghai Center for Systems BiomedicineShanghai Jiao Tong UniversityShanghaiChina
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer InstituteRenji Hospital affiliated to Shanghai Jiao Tong University Medical SchoolShanghaiChina
- School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghaiChina
| | - Yichao Lu
- Key Laboratory of Systems Biomedicine (Ministry of Education), Center for Comparative Biomedicine, Institute of Systems Biomedicine, Shanghai Center for Systems BiomedicineShanghai Jiao Tong UniversityShanghaiChina
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer InstituteRenji Hospital affiliated to Shanghai Jiao Tong University Medical SchoolShanghaiChina
- School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghaiChina
| | - Xiulian Shen
- Key Laboratory of Systems Biomedicine (Ministry of Education), Center for Comparative Biomedicine, Institute of Systems Biomedicine, Shanghai Center for Systems BiomedicineShanghai Jiao Tong UniversityShanghaiChina
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer InstituteRenji Hospital affiliated to Shanghai Jiao Tong University Medical SchoolShanghaiChina
- School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghaiChina
| | - Hong Shao
- Key Laboratory of Systems Biomedicine (Ministry of Education), Center for Comparative Biomedicine, Institute of Systems Biomedicine, Shanghai Center for Systems BiomedicineShanghai Jiao Tong UniversityShanghaiChina
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer InstituteRenji Hospital affiliated to Shanghai Jiao Tong University Medical SchoolShanghaiChina
- School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghaiChina
| | - Lun Suo
- Key Laboratory of Systems Biomedicine (Ministry of Education), Center for Comparative Biomedicine, Institute of Systems Biomedicine, Shanghai Center for Systems BiomedicineShanghai Jiao Tong UniversityShanghaiChina
- Department of Assisted ReproductionShanghai Jiao Tong University Medical SchoolShanghaiChina
| | - Qiang Wu
- Key Laboratory of Systems Biomedicine (Ministry of Education), Center for Comparative Biomedicine, Institute of Systems Biomedicine, Shanghai Center for Systems BiomedicineShanghai Jiao Tong UniversityShanghaiChina
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer InstituteRenji Hospital affiliated to Shanghai Jiao Tong University Medical SchoolShanghaiChina
- School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghaiChina
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17
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Yang Y, Guo Y. Elucidating the molecular mechanisms mediating plant salt-stress responses. New Phytol 2018; 217:523-539. [PMID: 29205383 DOI: 10.1111/nph.14920] [Citation(s) in RCA: 592] [Impact Index Per Article: 98.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 10/11/2017] [Indexed: 05/18/2023]
Abstract
Contents Summary 523 I. Introduction 523 II. Sensing salt stress 524 III. Ion homeostasis regulation 524 IV. Metabolite and cell activity responses to salt stress 527 V. Conclusions and perspectives 532 Acknowledgements 533 References 533 SUMMARY: Excess soluble salts in soil (saline soils) are harmful to most plants. Salt imposes osmotic, ionic, and secondary stresses on plants. Over the past two decades, many determinants of salt tolerance and their regulatory mechanisms have been identified and characterized using molecular genetics and genomics approaches. This review describes recent progress in deciphering the mechanisms controlling ion homeostasis, cell activity responses, and epigenetic regulation in plants under salt stress. Finally, we highlight research areas that require further research to reveal new determinants of salt tolerance in plants.
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Affiliation(s)
- Yongqing Yang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Yan Guo
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
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18
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Heinz LS, Muhs S, Schiewek J, Grüb S, Nalaskowski M, Lin YN, Wikman H, Oliveira-Ferrer L, Lange T, Wellbrock J, Konietzny A, Mikhaylova M, Windhorst S. Strong fascin expression promotes metastasis independent of its F-actin bundling activity. Oncotarget 2017; 8:110077-91. [PMID: 29299131 DOI: 10.18632/oncotarget.22249] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 09/27/2017] [Indexed: 11/25/2022] Open
Abstract
High expression of the actin bundling protein Fascin increases the malignancy of tumor cells. Here we show that fascin expression is up-regulated in more malignant sub-cell lines of MDA-MB-231 cells as compared to parental cells. Since also parental MDA-MB-231 cells exhibit high fascin levels, increased fascin expression was termed as “hyperexpression”. To examine the effect of fascin hyperexpression, fascin was hyperexpressed in parental MDA-MB-231 cells and metastasis was analyzed in NOD scid gamma (NSG) mice. In addition, the effect of fascin mutants with inactive or constitutively active actin bundling activity was examined. Unexpectedly, we found that hyperexpression of both, wildtype (wt) and mutant fascin strongly increased metastasis in vivo, showing that the effect of fascin hyperexpression did not depend on its actin bundling activity. Cellular assays revealed that hyperexpression of wt and mutant fascin increased adhesion of MDA-MB-231 cells while transmigration and proliferation were not affected. Since it has been shown that fascin controls adhesion by directly interacting with microtubules (MTs), we analyzed if fascin hyperexpression affects MT dynamics. We found that at high concentrations fascin significantly increased MT dynamics in cells and in cell-free approaches. In summary our data show that strong expression of fascin in breast cancer cells increases metastasis independent of its actin bundling activity. Thus, it seems that the mechanism of fascin-stimulated metastasis depends on its concentration.
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19
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Belvitch P, Brown ME, Brinley BN, Letsiou E, Rizzo AN, Garcia JGN, Dudek SM. The ARP 2/3 complex mediates endothelial barrier function and recovery. Pulm Circ 2017; 7:200-210. [PMID: 28680579 PMCID: PMC5448540 DOI: 10.1086/690307] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 11/23/2016] [Indexed: 01/03/2023] Open
Abstract
Pulmonary endothelial cell (EC) barrier dysfunction and recovery is critical to the pathophysiology of acute respiratory distress syndrome. Cytoskeletal and subsequent cell membrane dynamics play a key mechanistic role in determination of EC barrier integrity. Here, we characterizAQe the actin related protein 2/3 (Arp 2/3) complex, a regulator of peripheral branched actin polymerization, in human pulmonary EC barrier function through studies of transendothelial electrical resistance (TER), intercellular gap formation, peripheral cytoskeletal structures and lamellipodia. Compared to control, Arp 2/3 inhibition with the small molecule inhibitor CK-666 results in a reduction of baseline barrier function (1,241 ± 53 vs 988 ± 64 ohm; p < 0.01), S1P-induced barrier enhancement and delayed recovery of barrier function after thrombin (143 ± 14 vs 93 ± 6 min; p < 0.01). Functional changes of Arp 2/3 inhibition on barrier integrity are associated temporally with increased intercellular gap area at baseline (0.456 ± 0.02 vs 0.299 ± 0.02; p < 0.05) and thirty minutes after thrombin (0.885 ± 0.03 vs 0.754 ± 0.03; p < 0.05). Immunofluorescent microscopy reveals reduced lamellipodia formation after S1P and during thrombin recovery in Arp 2/3 inhibited cells. Individual lamellipodia demonstrate reduced depth following Arp 2/3 inhibition vs vehicle at baseline (1.83 ± 0.41 vs 2.55 ± 0.46 µm; p < 0.05) and thirty minutes after S1P treatment (1.53 ± 0.37 vs 2.09 ± 0.36 µm; p < 0.05). These results establish a critical role for Arp 2/3 activity in determination of pulmonary endothelial barrier function and recovery through formation of EC lamellipodia and closure of intercellular gaps.
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Affiliation(s)
- Patrick Belvitch
- Division of Pulmonary, Critical Care, Sleep, and Allergy, University of Illinois Hospital and Health Science System, Chicago, IL, USA
| | - Mary E Brown
- Division of Pulmonary, Critical Care, Sleep, and Allergy, University of Illinois Hospital and Health Science System, Chicago, IL, USA
| | | | - Eleftheria Letsiou
- Division of Pulmonary, Critical Care, Sleep, and Allergy, University of Illinois Hospital and Health Science System, Chicago, IL, USA
| | - Alicia N Rizzo
- Division of Pulmonary, Critical Care, Sleep, and Allergy, University of Illinois Hospital and Health Science System, Chicago, IL, USA
| | - Joe G N Garcia
- University of Arizona Health Sciences Center, Tucson, AZ, USA
| | - Steven M Dudek
- Division of Pulmonary, Critical Care, Sleep, and Allergy, University of Illinois Hospital and Health Science System, Chicago, IL, USA
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20
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Wagener BM, Hu M, Zheng A, Zhao X, Che P, Brandon A, Anjum N, Snapper S, Creighton J, Guan JL, Han Q, Cai GQ, Han X, Pittet JF, Ding Q. Neuronal Wiskott-Aldrich syndrome protein regulates TGF-β1-mediated lung vascular permeability. FASEB J 2016; 30:2557-69. [PMID: 27025963 DOI: 10.1096/fj.201600102r] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Accepted: 03/21/2016] [Indexed: 01/08/2023]
Abstract
TGF-β1 induces an increase in paracellular permeability and actin stress fiber formation in lung microvascular endothelial and alveolar epithelial cells via small Rho GTPase. The molecular mechanism involved is not fully understood. Neuronal Wiskott-Aldrich syndrome protein (N-WASP) has an essential role in actin structure dynamics. We hypothesized that N-WASP plays a critical role in these TGF-β1-induced responses. In these cell monolayers, we demonstrated that N-WASP down-regulation by short hairpin RNA prevented TGF-β1-mediated disruption of the cortical actin structure, actin stress filament formation, and increased permeability. Furthermore, N-WASP down-regulation blocked TGF-β1 activation mediated by IL-1β in alveolar epithelial cells, which requires actin stress fiber formation. Control short hairpin RNA had no effect on these TGF-β1-induced responses. TGF-β1-induced phosphorylation of Y256 of N-WASP via activation of small Rho GTPase and focal adhesion kinase mediates TGF-β1-induced paracellular permeability and actin cytoskeleton dynamics. In vivo, compared with controls, N-WASP down-regulation increases survival and prevents lung edema in mice induced by bleomycin exposure-a lung injury model in which TGF-β1 plays a critical role. Our data indicate that N-WASP plays a crucial role in the development of TGF-β1-mediated acute lung injury by promoting pulmonary edema via regulation of actin cytoskeleton dynamics.-Wagener, B. M., Hu, M., Zheng, A., Zhao, X., Che, P., Brandon, A., Anjum, N., Snapper, S., Creighton, J., Guan, J.-L., Han, Q., Cai, G.-Q., Han, X., Pittet, J.-F., Ding, Q. Neuronal Wiskott-Aldrich syndrome protein regulates TGF-β1-mediated lung vascular permeability.
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Affiliation(s)
- Brant M Wagener
- Division of Critical Care, Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA; Division of Molecular and Translational Biomedicine, Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Meng Hu
- Division of Pulmonary, Allergy, and Critical Care Medicine Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Anni Zheng
- Division of Pulmonary, Allergy, and Critical Care Medicine Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Xueke Zhao
- Division of Pulmonary, Allergy, and Critical Care Medicine Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA; Department of Infectious Diseases, Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou, China
| | - Pulin Che
- Division of Neurology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Angela Brandon
- Division of Molecular and Translational Biomedicine, Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Naseem Anjum
- Division of Molecular and Translational Biomedicine, Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Scott Snapper
- Department of Pathology, Harvard University, Boston, Massachusetts, USA
| | - Judy Creighton
- Division of Molecular and Translational Biomedicine, Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Jun-Lin Guan
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Qimei Han
- Division of Pulmonary, Allergy, and Critical Care Medicine Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Guo-Qiang Cai
- Division of Pulmonary, Allergy, and Critical Care Medicine Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Xiaosi Han
- Division of Neurology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Jean-Francois Pittet
- Division of Critical Care, Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA; Division of Molecular and Translational Biomedicine, Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA; Department of Surgery, University of Alabama at Birmingham, Birmingham, Alabama, USA; Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Qiang Ding
- Division of Pulmonary, Allergy, and Critical Care Medicine Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA; Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, USA
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21
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Affiliation(s)
- Richard S Vander Heide
- Department of Pathology, Louisiana State University Health Science Center, New Orleans, LA (R.S.V.H.)
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22
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Pappas CT, Mayfield RM, Henderson C, Jamilpour N, Cover C, Hernandez Z, Hutchinson KR, Chu M, Nam KH, Valdez JM, Wong PK, Granzier HL, Gregorio CC. Knockout of Lmod2 results in shorter thin filaments followed by dilated cardiomyopathy and juvenile lethality. Proc Natl Acad Sci U S A 2015; 112:13573-8. [PMID: 26487682 DOI: 10.1073/pnas.1508273112] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Leiomodin 2 (Lmod2) is an actin-binding protein that has been implicated in the regulation of striated muscle thin filament assembly; its physiological function has yet to be studied. We found that knockout of Lmod2 in mice results in abnormally short thin filaments in the heart. We also discovered that Lmod2 functions to elongate thin filaments by promoting actin assembly and dynamics at thin filament pointed ends. Lmod2-KO mice die as juveniles with hearts displaying contractile dysfunction and ventricular chamber enlargement consistent with dilated cardiomyopathy. Lmod2-null cardiomyocytes produce less contractile force than wild type when plated on micropillar arrays. Introduction of GFP-Lmod2 via adeno-associated viral transduction elongates thin filaments and rescues structural and functional defects observed in Lmod2-KO mice, extending their lifespan to adulthood. Thus, to our knowledge, Lmod2 is the first identified mammalian protein that functions to elongate actin filaments in the heart; it is essential for cardiac thin filaments to reach a mature length and is required for efficient contractile force and proper heart function during development.
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Abstract
Advances in microscopy techniques applied to living cells have dramatically transformed our view of the actin cytoskeleton as a framework for cellular processes. Conventional fluorescence imaging and static analyses are useful for quantifying cellular architecture and the network of filaments that support vesicle trafficking, organelle movement, and response to biotic stress. However, new imaging techniques have revealed remarkably dynamic features of individual actin filaments and the mechanisms that underpin their construction and turnover. In this review, we briefly summarize knowledge about actin and actin-binding proteins in plant systems. We focus on the quantitative properties of the turnover of individual actin filaments, highlight actin-binding proteins that participate in actin dynamics, and summarize the current genetic evidence that has been used to dissect specific aspects of the stochastic dynamics model. Finally, we describe some signaling pathways in which recent data implicate changes in actin filament dynamics and the associated cytoplasmic responses.
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Affiliation(s)
- Jiejie Li
- Department of Biological Sciences and
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24
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Pedraza CE, Taylor C, Pereira A, Seng M, Tham CS, Izrael M, Webb M. Induction of oligodendrocyte differentiation and in vitro myelination by inhibition of rho-associated kinase. ASN Neuro 2014; 6:6/4/1759091414538134. [PMID: 25289646 PMCID: PMC4189421 DOI: 10.1177/1759091414538134] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
In inflammatory demyelinating diseases such as multiple sclerosis (MS), myelin
degradation results in loss of axonal function and eventual axonal degeneration.
Differentiation of resident oligodendrocyte precursor cells (OPCs) leading to
remyelination of denuded axons occurs regularly in early stages of MS but halts as
the pathology transitions into progressive MS. Pharmacological potentiation of
endogenous OPC maturation and remyelination is now recognized as a promising
therapeutic approach for MS. In this study, we analyzed the effects of modulating the
Rho-A/Rho-associated kinase (ROCK) signaling pathway, by the use of selective
inhibitors of ROCK, on the transformation of OPCs into mature, myelinating
oligodendrocytes. Here we demonstrate, with the use of cellular cultures from rodent
and human origin, that ROCK inhibition in OPCs results in a significant generation of
branches and cell processes in early differentiation stages, followed by accelerated
production of myelin protein as an indication of advanced maturation. Furthermore,
inhibition of ROCK enhanced myelin formation in cocultures of human OPCs and neurons
and remyelination in rat cerebellar tissue explants previously demyelinated with
lysolecithin. Our findings indicate that by direct inhibition of this signaling
molecule, the OPC differentiation program is activated resulting in morphological and
functional cell maturation, myelin formation, and regeneration. Altogether, we show
evidence of modulation of the Rho-A/ROCK signaling pathway as a viable target for the
induction of remyelination in demyelinating pathologies.
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Affiliation(s)
- Carlos E Pedraza
- EMD Serono Research & Development Institute, Inc., Billerica, MA, USA
| | | | - Albertina Pereira
- EMD Serono Research & Development Institute, Inc., Billerica, MA, USA
| | - Michelle Seng
- EMD Serono Research & Development Institute, Inc., Billerica, MA, USA
| | - Chui-Se Tham
- EMD Serono Research & Development Institute, Inc., Billerica, MA, USA
| | | | - Michael Webb
- EMD Serono Research & Development Institute, Inc., Billerica, MA, USA
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25
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Abstract
Mechanical interactions play a key role in many processes associated with neuronal growth and development. Over the last few years there has been significant progress in our understanding of the role played by the substrate stiffness in neuronal growth, of the cell-substrate adhesion forces, of the generation of traction forces during axonal elongation, and of the relationships between the neuron soma elastic properties and its health. The particular capabilities of the Atomic Force Microscope (AFM), such as high spatial resolution, high degree of control over the magnitude and orientation of the applied forces, minimal sample damage, and the ability to image and interact with cells in physiologically relevant conditions make this technique particularly suitable for measuring mechanical properties of living neuronal cells. This article reviews recent advances on using the AFM for studying neuronal biomechanics, provides an overview about the state-of-the-art measurements, and suggests directions for future applications.
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Affiliation(s)
- Elise Spedden
- Department of Physics and Astronomy and Center for Nanoscopic Physics, Tufts University, 4 Colby Street, Medford, MA 02155, USA; E-Mail:
| | - Cristian Staii
- Department of Physics and Astronomy and Center for Nanoscopic Physics, Tufts University, 4 Colby Street, Medford, MA 02155, USA; E-Mail:
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Abstract
MyTH/FERM (myosin tail homology 4/band 4.1, ezrin, radixin, and moesin) myosins have roles in cellular adhesion, extension of actin-filled projections such as filopodia and stereocilia, and directional migration. The amoeba Dictyostelium discoideum expresses a simple complement of MyTH/FERM myosins, a class VII (M7) myosin required for cell-substrate adhesion and a unique myosin named MyoG. Mutants lacking MyoG exhibit a wide range of normal actin-based behaviors, including chemotaxis to folic acid, but have a striking defect in polarization and chemotaxis to cAMP. Although the myoG mutants respond to cAMP stimulation by increasing persistence and weakly increasing levels of cortical F-actin, they do not polarize; instead, they maintain a round shape and move slowly and randomly when exposed to a chemotactic gradient. The mutants also fail to activate and localize PI3K to the membrane closest to the source of chemoattractant. These data reveal a role for a MyTH/FERM myosin in mediating early chemotactic signaling and suggest that MyTH/FERM proteins have conserved roles in signaling and the generation of cell polarity.
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Affiliation(s)
- Laura M. Breshears
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455; and
| | - Deborah Wessels
- Department of Biological Sciences, University of Iowa, Iowa City, IA 52242
| | - David R. Soll
- Department of Biological Sciences, University of Iowa, Iowa City, IA 52242
| | - Margaret A. Titus
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455; and
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27
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Sherbet GV. Metastasis Promoter S100A4 is a Potential Molecular Therapeutic Target. Cancer Genomics Proteomics 2006; 3:203-216. [PMID: 31394699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2006] [Accepted: 05/24/2006] [Indexed: 06/10/2023] Open
Abstract
S100A4, a member of the S100 family of proteins involved in calcium signalling, has come into the fore in recent years on account of its close relationship with tumour development and progression; therefore, S100A4 commends itself as a prime therapeutic target. The phenotypic effects of S100A4 are generated via diverse signalling pathways encompassing and incorporating the functions of cell cycle regulators, growth factor receptors, extracellular matrix components, and the inducers of angiogenesis and lymphangiogenesis. By virtue of this, S100A4 signalling can be specifically targeted to down-regulate the phenotypic activities that contribute to the growth, invasion and metastasis of cancer. Here, the discussion has focused on the signalling pathways that S100A4 uses, with a view to identifying the most effective targets to which drugs can be designed and specifically directed. Some approaches to the problem of inhibiting or deregulating the functions of S100A4, to control invasion and metastasis have been identified. S100A4 could provide a wide channel to control the growth, invasion and secondary spread of cancer and, thus, amply rationalise and validate it as an important therapeutic target.
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Affiliation(s)
- G V Sherbet
- School of Electrical, Electronic and Computer Engineering, University of Newcastle upon Tyne, U.K.
- The Institute for Molecular Medicine, Huntington Beach CA, U.S.A.
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28
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Liu WK, Liu Y, Farrell D, Zhang L, Wang XS, Fukui Y, Patankar N, Zhang Y, Bajaj C, Lee J, Hong J, Chen X, Hsu H. Immersed finite element method and its applications to biological systems. Comput Methods Appl Mech Eng 2006; 195:1722-1749. [PMID: 20200602 PMCID: PMC2830735 DOI: 10.1016/j.cma.2005.05.049] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
This paper summarizes the newly developed immersed finite element method (IFEM) and its applications to the modeling of biological systems. This work was inspired by the pioneering work of Professor T.J.R. Hughes in solving fluid-structure interaction problems. In IFEM, a Lagrangian solid mesh moves on top of a background Eulerian fluid mesh which spans the entire computational domain. Hence, mesh generation is greatly simplified. Moreover, both fluid and solid domains are modeled with the finite element method and the continuity between the fluid and solid subdomains is enforced via the interpolation of the velocities and the distribution of the forces with the reproducing Kernel particle method (RKPM) delta function. The proposed method is used to study the fluid-structure interaction problems encountered in human cardiovascular systems. Currently, the heart modeling is being constructed and the deployment process of an angioplasty stent has been simulated. Some preliminary results on monocyte and platelet deposition are presented. Blood rheology, in particular, the shear-rate dependent de-aggregation of red blood cell (RBC) clusters and the transport of deformable cells, are modeled. Furthermore, IFEM is combined with electrokinetics to study the mechanisms of nano/bio filament assembly for the understanding of cell motility.
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Affiliation(s)
- Wing Kam Liu
- Department of Mechanical Engineering, 2145 Sheridan Road, Northwestern University, Evanston, IL 60208, United States
- Corresponding author. Tel.: +1 847 491 7094; fax: +1 847 491 3915. (W.K. Liu)
| | - Yaling Liu
- Department of Mechanical Engineering, 2145 Sheridan Road, Northwestern University, Evanston, IL 60208, United States
| | - David Farrell
- Department of Mechanical Engineering, 2145 Sheridan Road, Northwestern University, Evanston, IL 60208, United States
| | - Lucy Zhang
- Department of Mechanical Engineering, Tulane University, 6823 Saint Charles Avenue, New Orleans, LA 70118, United States
| | - X. Sheldon Wang
- Department of Mathematical Sciences, New Jersey Institute of Technology, University Heights, Newark, NJ 07102, United States
| | - Yoshio Fukui
- Department of Mechanical Engineering, 2145 Sheridan Road, Northwestern University, Evanston, IL 60208, United States
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, 303 East Chicago Avenue, Chicago, IL 60611, United States
| | - Neelesh Patankar
- Department of Mechanical Engineering, 2145 Sheridan Road, Northwestern University, Evanston, IL 60208, United States
| | - Yongjie Zhang
- Institute for Computational Engineering and Sciences, Department of Computer Sciences, The University of Texas at Austin, Austin, TX 78712, United States
| | - Chandrajit Bajaj
- Institute for Computational Engineering and Sciences, Department of Computer Sciences, The University of Texas at Austin, Austin, TX 78712, United States
| | - Junghoon Lee
- School of Mechanical and Aerospace Engineering, Seoul National University, San 56-1 Shinlim, Kwanak, Seoul 151-742, Republic of Korea
| | - Juhee Hong
- School of Mechanical and Aerospace Engineering, Seoul National University, San 56-1 Shinlim, Kwanak, Seoul 151-742, Republic of Korea
| | - Xinyu Chen
- Department of Mechanical Engineering, 2145 Sheridan Road, Northwestern University, Evanston, IL 60208, United States
| | - Huayi Hsu
- Department of Mechanical Engineering, 2145 Sheridan Road, Northwestern University, Evanston, IL 60208, United States
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