1
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Pankova V, Krasny L, Kerrison W, Tam YB, Chadha M, Burns J, Wilding CP, Chen L, Chowdhury A, Perkins E, Lee AT, Howell L, Guljar N, Sisley K, Fisher C, Chudasama P, Thway K, Jones RL, Huang PH. Clinical Implications and Molecular Features of Extracellular Matrix Networks in Soft Tissue Sarcomas. Clin Cancer Res 2024; 30:3229-3242. [PMID: 38810090 PMCID: PMC11292195 DOI: 10.1158/1078-0432.ccr-23-3960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 04/25/2024] [Accepted: 05/23/2024] [Indexed: 05/31/2024]
Abstract
PURPOSE The landscape of extracellular matrix (ECM) alterations in soft tissue sarcomas (STS) remains poorly characterized. We aimed to investigate the tumor ECM and adhesion signaling networks present in STS and their clinical implications. EXPERIMENTAL DESIGN Proteomic and clinical data from 321 patients across 11 histological subtypes were analyzed to define ECM and integrin adhesion networks. Subgroup analysis was performed in leiomyosarcomas (LMS), dedifferentiated liposarcomas (DDLPS), and undifferentiated pleomorphic sarcomas (UPS). RESULTS This analysis defined subtype-specific ECM profiles including enrichment of basement membrane proteins in LMS and ECM proteases in UPS. Across the cohort, we identified three distinct coregulated ECM networks which are associated with tumor malignancy grade and histological subtype. Comparative analysis of LMS cell line and patient proteomic data identified the lymphocyte cytosolic protein 1 cytoskeletal protein as a prognostic factor in LMS. Characterization of ECM network events in DDLPS revealed three subtypes with distinct oncogenic signaling pathways and survival outcomes. Evaluation of the DDLPS subtype with the poorest prognosis nominates ECM remodeling proteins as candidate antistromal therapeutic targets. Finally, we define a proteoglycan signature that is an independent prognostic factor for overall survival in DDLPS and UPS. CONCLUSIONS STS comprise heterogeneous ECM signaling networks and matrix-specific features that have utility for risk stratification and therapy selection, which could in future guide precision medicine in these rare cancers.
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Affiliation(s)
- Valeriya Pankova
- Division of Molecular Pathology, The Institute of Cancer Research, London, United Kingdom.
| | - Lukas Krasny
- Division of Molecular Pathology, The Institute of Cancer Research, London, United Kingdom.
| | - William Kerrison
- Division of Molecular Pathology, The Institute of Cancer Research, London, United Kingdom.
| | - Yuen B. Tam
- Division of Molecular Pathology, The Institute of Cancer Research, London, United Kingdom.
| | - Madhumeeta Chadha
- Division of Molecular Pathology, The Institute of Cancer Research, London, United Kingdom.
| | - Jessica Burns
- Division of Molecular Pathology, The Institute of Cancer Research, London, United Kingdom.
| | - Christopher P. Wilding
- Division of Molecular Pathology, The Institute of Cancer Research, London, United Kingdom.
| | - Liang Chen
- Precision Sarcoma Research Group, German Cancer Research Center (DKFZ), Heidelberg, Germany.
- National Center for Tumor Diseases, Heidelberg, Germany.
| | - Avirup Chowdhury
- Division of Molecular Pathology, The Institute of Cancer Research, London, United Kingdom.
| | - Emma Perkins
- Division of Molecular Pathology, The Institute of Cancer Research, London, United Kingdom.
| | | | - Louise Howell
- Light Microscopy Facility, The Institute of Cancer Research, London, United Kingdom.
| | - Nafia Guljar
- Division of Molecular Pathology, The Institute of Cancer Research, London, United Kingdom.
| | - Karen Sisley
- Division of Clinical Medicine, The Medical School, University of Sheffield, Sheffield, United Kingdom.
| | - Cyril Fisher
- University Hospitals Birmingham NHS Foundation Trust, Birmingham, United Kingdom.
| | - Priya Chudasama
- Precision Sarcoma Research Group, German Cancer Research Center (DKFZ), Heidelberg, Germany.
- National Center for Tumor Diseases, Heidelberg, Germany.
| | - Khin Thway
- Division of Molecular Pathology, The Institute of Cancer Research, London, United Kingdom.
- The Royal Marsden NHS Foundation Trust, London, United Kingdom.
| | - Robin L. Jones
- The Royal Marsden NHS Foundation Trust, London, United Kingdom.
- Division of Clinical Studies, The Institute of Cancer Research, London, United Kingdom.
| | - Paul H. Huang
- Division of Molecular Pathology, The Institute of Cancer Research, London, United Kingdom.
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Hernandez RA, Hearn JI, Bhoopalan V, Hamzeh AR, Kwong K, Diamand K, Davies A, Li FJ, Padmanabhan H, Milne R, Ballard F, Spensberger D, Gardiner EE, Miraghazadeh B, Enders A, Cook MC. L-plastin associated syndrome of immune deficiency and hematologic cytopenia. J Allergy Clin Immunol 2024:S0091-6749(24)00458-5. [PMID: 38710235 DOI: 10.1016/j.jaci.2024.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 04/01/2024] [Accepted: 05/01/2024] [Indexed: 05/08/2024]
Abstract
BACKGROUND LCP1 encodes L-plastin, an actin-bundling protein primarily expressed in hematopoietic cells. In mouse and fish models, LCP1 deficiency has been shown to result in hematologic and immune defects. OBJECTIVE This study aimed to determine the nature of a human inborn error of immunity resulting from a novel genetic variant of LCP1. METHODS We performed genetic, protein, and cellular analysis of PBMCs from a kindred with apparent autosomal dominant immune deficiency. We identified a candidate causal mutation in LCP1, which we evaluated by engineering the orthologous mutation in mice and Jurkat cells. RESULTS A splice-site variant in LCP1 segregated with lymphopenia, neutropenia, and thrombocytopenia. The splicing defect resulted in at least 2 aberrant transcripts, producing an in-frame deletion of 24 nucleotides, and a frameshift deletion of exon 8. Cellular analysis of the kindred revealed a proportionate reduction of T and B cells and a mild expansion of transitional B cells. Similarly, mice carrying the orthologous genetic variant exhibited the same in-frame aberrant transcript, reduced expression Lcp1 and gene dose-dependent leukopenia, mild thrombocytopenia, and lymphopenia, with a significant reduction of T-cell populations. Functional analysis revealed that LCP1c740-1G>A confers a defect in platelet development and function with aberrant spreading on collagen. Immunologic analysis revealed defective actin organization in T cells, reduced migration of PBMCs from patients, splenocytes from mutant mice, and a mutant Jurkat cell line in response to CXCL12; impaired germinal center B-cell expansion after immunization; and reduced cytokinesis during T cell proliferation. CONCLUSIONS We describe a unique human hematopoietic defect affecting neutrophils, lymphocytes, and platelets arising from partial LCP1 deficiency.
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Affiliation(s)
- Raquel A Hernandez
- Division of Immunology and Infectious Diseases, John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - James I Hearn
- Division of Genome Sciences and Cancer, John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - Vijay Bhoopalan
- Division of Genome Sciences and Cancer, John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | | | - Kristy Kwong
- Australian Phenomics Facility and John Curtin School of Medical Research, Australian National University, Canberra, Australia; Cambridge Institute of Therapeutic Immunology and Infectious Disease, Department of Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Koula Diamand
- Australian Phenomics Facility and John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - Ainsley Davies
- Australian Phenomics Facility and John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - Fei-Ju Li
- Australian Phenomics Facility and John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - Harish Padmanabhan
- Australian Phenomics Facility and John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - Rachel Milne
- Australian Phenomics Facility and John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - Fiona Ballard
- Division of Immunology and Infectious Diseases, John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - Dominik Spensberger
- Australian Phenomics Facility and John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - Elizabeth E Gardiner
- Division of Genome Sciences and Cancer, John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - Bahar Miraghazadeh
- Division of Immunology and Infectious Diseases, John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - Anselm Enders
- Division of Immunology and Infectious Diseases, John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - Matthew C Cook
- Division of Immunology and Infectious Diseases, John Curtin School of Medical Research, Australian National University, Canberra, Australia; Canberra Clinical Genomics, Canberra, Australia; Cambridge Institute of Therapeutic Immunology and Infectious Disease, Department of Medicine, University of Cambridge, Cambridge, United Kingdom.
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3
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Linehan JB, Zepeda JL, Mitchell TA, LeClair EE. Follow that cell: leukocyte migration in L-plastin mutant zebrafish. Cytoskeleton (Hoboken) 2022; 79:26-37. [PMID: 35811499 DOI: 10.1002/cm.21717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 06/21/2022] [Accepted: 07/07/2022] [Indexed: 11/09/2022]
Abstract
Actin assemblies are important in motile cells such as leukocytes which form dynamic plasma membrane extensions or podia. L-plastin (LCP1) is a leukocyte-specific calcium-dependent actin-bundling protein that, in mammals, is known to affect immune cell migration. Previously, we generated CRISPR/Cas9 engineered zebrafish lacking L-plastin (lcp1-/-) and reported that they had reduced survival to adulthood, suggesting that lack of this actin-bundler might negatively affect the immune system. To test this hypothesis, we examined the distribution and migration of neutrophils and macrophages in the transparent tail of early zebrafish larvae using cell-specific markers and an established wound-migration assay. Knockout larvae were similar to their heterozygous siblings in having equal body sizes and comparable numbers of neutrophils in caudal hematopoietic tissue at two days post-fertilization, indicating no gross defect in neutrophil production or developmental migration. When stimulated by a tail wound, all genotypes of neutrophils were equally migratory in a two-hour window. However for macrophages we observed both migration defects and morphological differences. L-plastin knockout macrophages (lcp1 -/-) still homed to wounds but were slower, less directional and had a star-like morphology with many leading and trailing projections. In contrast, heterozygous macrophages lcp1 (+/-) were faster, more directional, and had a streamlined, slug-like morphology. Overall, these findings show that in larval zebrafish L-plastin knockout primarily affects the macrophage response with possible consequences for organismal immunity. Consistent with our observations, we propose a model in which cytoplasmic L-plastin negatively regulates macrophage integrin adhesion by holding these transmembrane heterodimers in a 'clasped', inactive form and is a necessary part of establishing macrophage polarity during chemokine-induced motility. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- J B Linehan
- Department of Biological Sciences, DePaul University, USA
| | - J L Zepeda
- Department of Biological Sciences, DePaul University, USA
| | - T A Mitchell
- Department of Biological Sciences, DePaul University, USA
| | - E E LeClair
- Department of Biological Sciences, DePaul University, USA
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4
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Joshi H, Morley SC. Efficient T Cell Migration and Activation Require L-Plastin. Front Immunol 2022; 13:916137. [PMID: 35844504 PMCID: PMC9277003 DOI: 10.3389/fimmu.2022.916137] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 06/02/2022] [Indexed: 11/28/2022] Open
Abstract
Rapid re-organization of the actin cytoskeleton supports T-cell trafficking towards immune sites and interaction with antigen presenting cells (APCs). F-actin rearrangement enables T-cell trafficking by stabilizing adhesion to vascular endothelial cells and promoting transendothelial migration. T-cell/APC immune synapse (IS) maturation also relies upon f-actin-anchored LFA-1:ICAM-1 ligation. Therefore, efficient T-cell responses require tight regulation of f-actin dynamics. In this review, we summarize how the actin-bundling protein L-plastin (LPL) regulates T-cell activation and migration. LPL enhances f-actin polymerization and also directly binds to the β2 chain of the integrin LFA-1 to support intercellular adhesion and IS formation in human and murine T cells. LPL- deficient T cells migrate slowly in response to chemo-attractants such as CXCL12, CCL19, and poorly polarize towards ICAM-1. Loss of LPL impairs thymic egress and intranodal motility. LPL is also required for T-cell IS maturation with APCs, and therefore for efficient cytokine production and proliferation. LPL-/- mice are less susceptible to T-cell mediated pathologies, such as allograft rejection and experimental autoimmune encephalomyelitis (EAE). LPL activity is regulated by its N-terminal “headpiece”, which contains serine and threonine phosphorylation and calcium- and calmodulin-binding sites. LPL phosphorylation is required for lamellipodia formation during adhesion and migration, and also for LFA-1 clustering during IS formation. However, the precise molecular interactions by which LPL supports T-cell functional responses remain unclear. Future studies elucidating LPL-mediated regulation of T-cell migration and/or activation may illuminate pathways for therapeutic targeting in T-cell-mediated diseases.
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Affiliation(s)
- Hemant Joshi
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, United States
- Division of Immunobiology, Department of Immunology and Pathology, Washington University School of Medicine, St. Louis, MO, United States
| | - Sharon Celeste Morley
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, United States
- Division of Immunobiology, Department of Immunology and Pathology, Washington University School of Medicine, St. Louis, MO, United States
- *Correspondence: Sharon Celeste Morley,
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5
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Allosteric regulation controls actin-bundling properties of human plastins. Nat Struct Mol Biol 2022; 29:519-528. [PMID: 35589838 DOI: 10.1038/s41594-022-00771-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 04/05/2022] [Indexed: 11/08/2022]
Abstract
Plastins/fimbrins are conserved actin-bundling proteins contributing to motility, cytokinesis and other cellular processes by organizing strikingly different actin assemblies as in aligned bundles and branched networks. We propose that this ability of human plastins stems from an allosteric communication between their actin-binding domains (ABD1/2) engaged in a tight spatial association. Here we show that ABD2 can bind actin three orders of magnitude stronger than ABD1, unless the domains are involved in an equally strong inhibitory engagement. A mutation mimicking physiologically relevant phosphorylation at the ABD1-ABD2 interface greatly weakened their association, dramatically potentiating actin cross-linking. Cryo-EM reconstruction revealed the ABD1-actin interface and enabled modeling of the plastin bridge and domain separation in parallel bundles. We predict that a strong and tunable allosteric inhibition between the domains allows plastins to modulate the cross-linking strength, contributing to remodeling of actin assemblies of different morphologies defining the unique place of plastins in actin organization.
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6
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Chellaiah MA. L-Plastin Phosphorylation: Possible Regulation by a TNFR1 Signaling Cascade in Osteoclasts. Cells 2021; 10:2432. [PMID: 34572081 PMCID: PMC8464874 DOI: 10.3390/cells10092432] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 08/25/2021] [Accepted: 09/09/2021] [Indexed: 12/30/2022] Open
Abstract
Tumor necrosis factor-alpha (TNF-α) signaling regulates phosphorylation of L-plastin, which is involved in forming the nascent sealing zone, a precursor zone for the matured sealing ring. This study aimed to illustrate the molecular mechanisms of L-plastin phosphorylation and the subsequent formation of the nascent sealing zone in osteoclasts treated with TNF-α. Here, we report that anti-TNF-receptor 1, inhibitors of signaling proteins (Src, PI3-K, Rho, and Rho-kinase), and siRNA of TRAF-6 attenuated the phosphorylation of LPL and filamentous actin content significantly in the presence of TNF-α. An inhibitor of integrin αvβ3, PKC, or PKA did not inhibit TNF-α-induced L-plastin phosphorylation. Inhibitors of Src and PI3-K and not Rho or Rho-kinase reduced tyrosine phosphorylation of TRAF-6, suggesting that Src and PI3-K regulate TRAF-6 phosphorylation, and Rho and Rho-kinase are downstream of TRAF-6 regulation. Osteoclasts expressing constitutively active or kinase-defective Src proteins were used to determine the role of Src on L-plastin phosphorylation; similarly, the effect of Rho was confirmed by transducing TAT-fused constitutively active (V14) or dominant-negative (N19) Rho proteins into osteoclasts. Pull-down analysis with glutathione S-transferase-fused SH2 and SH3 domains of Src and PI3-K demonstrated coprecipitation of L-plastin and TRAF-6 with the SH3 and SH2 domains of the PI3-K and Src proteins. However, the actual order of the interaction of proteins requires further elucidation; a comprehensive screening should corroborate the initial findings of protein interactions via the SH2/SH3 domains. Ultimately, inhibition of the interaction of proteins with SH2/SH3 could reduce L-plastin phosphorylation and affect NSZ formation and bone resorption in conditions that display osteoclast activation and bone loss.
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Affiliation(s)
- Meenakshi A Chellaiah
- Department of Oncology and Diagnostic Sciences, School of Dentistry, University of Maryland, Baltimore, MD 21201, USA
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7
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Wabnitz GH, Honus S, Habicht J, Orlik C, Kirchgessner H, Samstag Y. LFA-1 cluster formation in T-cells depends on L-plastin phosphorylation regulated by P90 RSK and PP2A. Cell Mol Life Sci 2021; 78:3543-3564. [PMID: 33449151 PMCID: PMC11072591 DOI: 10.1007/s00018-020-03744-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 11/21/2020] [Accepted: 12/15/2020] [Indexed: 10/25/2022]
Abstract
The integrin LFA-1 is crucial for T-cell/ APC interactions and sensitive recognition of antigens. Precise nanoscale organization and valency regulation of LFA-1 are mandatory for an appropriate function of the immune system. While the inside-out signals regulating the LFA-1 affinity are well described, the molecular mechanisms controlling LFA-1 avidity are still not fully understood. Here, we show that activation of the actin-bundling protein L-plastin (LPL) through phosphorylation at serine-5 enables the formation of clusters containing LFA-1 in high-affinity conformation. Phosphorylation of LPL is induced by an nPKC-MEK-p90RSK pathway and counter-regulated by the serine-threonine phosphatase PP2A. Interestingly, recruitment of LFA-1 into the T-cell/APC contact zone is not affected by LPL phosphorylation. Instead, for this process, activation of the actin-remodeling protein cofilin through dephosphorylation is essential. Together, this study reveals a dichotomic spatial regulation of LFA-1 clustering and microscale movement in T-cells by two different actin-binding proteins, LPL and cofilin.
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Affiliation(s)
- Guido H Wabnitz
- Institute of Immunology, Section Molecular Immunology, Heidelberg University, Im Neuenheimer Feld 305, 69120, Heidelberg, Germany.
| | - Sibylle Honus
- Institute of Immunology, Section Molecular Immunology, Heidelberg University, Im Neuenheimer Feld 305, 69120, Heidelberg, Germany
| | - Jüri Habicht
- Institute of Immunology, Section Molecular Immunology, Heidelberg University, Im Neuenheimer Feld 305, 69120, Heidelberg, Germany
| | - Christian Orlik
- Institute of Immunology, Section Molecular Immunology, Heidelberg University, Im Neuenheimer Feld 305, 69120, Heidelberg, Germany
| | - Henning Kirchgessner
- Institute of Immunology, Section Molecular Immunology, Heidelberg University, Im Neuenheimer Feld 305, 69120, Heidelberg, Germany
| | - Yvonne Samstag
- Institute of Immunology, Section Molecular Immunology, Heidelberg University, Im Neuenheimer Feld 305, 69120, Heidelberg, Germany
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8
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Schaffner-Reckinger E, Machado RAC. The actin-bundling protein L-plastin-A double-edged sword: Beneficial for the immune response, maleficent in cancer. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2020; 355:109-154. [PMID: 32859369 DOI: 10.1016/bs.ircmb.2020.05.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The dynamic organization of the actin cytoskeleton into bundles and networks is orchestrated by a large variety of actin-binding proteins. Among them, the actin-bundling protein L-plastin is normally expressed in hematopoietic cells, where it is involved in the immune response. However, L-plastin is also often ectopically expressed in malignant cancer cells of non-hematopoietic origin and is even considered as a marker for cancer progression. Post-translational modification modulates L-plastin activity. In particular, L-plastin Ser5 phosphorylation has been shown to be important for the immune response in leukocytes as well as for invasion and metastasis formation of carcinoma cells. This chapter discusses the physiological and pathological role of L-plastin with a special focus on the importance of L-plastin Ser5 phosphorylation for the protein functions. The potential use of Ser5 phosphorylated L-plastin as a biomarker and/or therapeutic target will be evoked.
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Affiliation(s)
- Elisabeth Schaffner-Reckinger
- Cancer Cell Biology and Drug Discovery Group, Faculty of Science, Technology and Medicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg.
| | - Raquel A C Machado
- Cancer Cell Biology and Drug Discovery Group, Faculty of Science, Technology and Medicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
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9
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Yang T, Yang WX. The dynamics and regulation of microfilament during spermatogenesis. Gene 2020; 744:144635. [PMID: 32244053 DOI: 10.1016/j.gene.2020.144635] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 02/28/2020] [Accepted: 03/30/2020] [Indexed: 12/22/2022]
Abstract
Spermatogenesis is a highly complex physiological process which contains spermatogonia proliferation, spermatocyte meiosis and spermatid morphogenesis. In the past decade, actin binding proteins and signaling pathways which are critical for regulating the actin cytoskeleton in testis had been found. In this review, we summarized 5 actin-binding proteins that have been proven to play important roles in the seminiferous epithelium. Lack of them perturbs spermatids polarity and the transport of spermatids. The loss of Arp2/3 complex, Formin1, Eps8, Palladin and Plastin3 cause sperm release failure suggesting their irreplaceable role in spermatogenesis. Actin regulation relies on multiple signal pathways. The PI3K/Akt signaling pathway positively regulate the mTOR pathway to promote actin reorganization in seminiferous epithelium. Conversely, TSC1/TSC2 complex, the upstream of mTOR, is activated by the LKB1/AMPK pathway to inhibit cell proliferation, differentiation and migration. The increasing researches focus on the function of actin binding proteins (ABPs), however, their collaborative regulation of actin patterns and potential regulatory signaling networks remains unclear. We reviewed ABPs that play important roles in mammalian spermatogenesis and signal pathways involved in the regulation of microfilaments. We suggest that more relevant studies should be performed in the future.
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Affiliation(s)
- Tong Yang
- The Sperm Laboratory, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Wan-Xi Yang
- The Sperm Laboratory, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
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Intermittent rolling is a defect of the extravasation cascade caused by Myosin1e-deficiency in neutrophils. Proc Natl Acad Sci U S A 2019; 116:26752-26758. [PMID: 31811025 DOI: 10.1073/pnas.1902502116] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Neutrophil extravasation is a migratory event in response to inflammation that depends on cytoskeletal dynamics regulated by myosins. Myosin-1e (Myo1e) is a long-tailed class-I myosin that has not yet been studied in the context of neutrophil-endothelial interactions and neutrophil extravasation. Intravital microscopy of TNFα-inflamed cremaster muscles in Myo1e-deficient mice revealed that Myo1e is required for efficient neutrophil extravasation. Specifically, Myo1e deficiency caused increased rolling velocity, decreased firm adhesion, aberrant crawling, and strongly reduced transmigration. Interestingly, we observed a striking discontinuous rolling behavior termed "intermittent rolling," during which Myo1e-deficient neutrophils showed alternating rolling and jumping movements. Surprisingly, chimeric mice revealed that these effects were due to Myo1e deficiency in leukocytes. Vascular permeability was not significantly altered in Myo1e KO mice. Myo1e-deficient neutrophils showed diminished arrest, spreading, uropod formation, and chemotaxis due to defective actin polymerization and integrin activation. In conclusion, Myo1e critically regulates adhesive interactions of neutrophils with the vascular endothelium and neutrophil extravasation. Myo1e may therefore be an interesting target in chronic inflammatory diseases characterized by excessive neutrophil recruitment.
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11
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Engineering of L-Plastin Peptide-Loaded Biodegradable Nanoparticles for Sustained Delivery and Suppression of Osteoclast Function In Vitro. Int J Cell Biol 2019; 2019:6943986. [PMID: 31191656 PMCID: PMC6525930 DOI: 10.1155/2019/6943986] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Revised: 04/09/2019] [Accepted: 04/15/2019] [Indexed: 12/15/2022] Open
Abstract
We have recently demonstrated that a small molecular weight amino-terminal peptide of L-plastin (10 amino acids; “MARGSVSDEE”) suppressed the phosphorylation of endogenous L-plastin. Therefore, the formation of nascent sealing zones (NSZs) and bone resorption are reduced. The aim of this study was to develop a biodegradable and biocompatible PLGA nanocarrier that could be loaded with the L-plastin peptide of interest and determine the efficacy in vitro in osteoclast cultures. L-plastin MARGSVSDEE (P1) and scrambled control (P3) peptide-loaded PLGA-PEG nanoparticles (NP1 and NP3, respectively) were synthesized by double emulsion technique. The biological effect of nanoparticles on osteoclasts was evaluated by immunoprecipitation, immunoblotting, rhodamine-phalloidin staining of actin filaments, and pit forming assays. Physical characterization of well-dispersed NP1 and NP3 demonstrated ~130-150 nm size, < 0.07 polydispersity index, ~-3 mV ζ-potential, and a sustained release of the peptide for three weeks. Biological characterization in osteoclast cultures demonstrated the following: NP1 significantly reduced (a) endogenous L-plastin phosphorylation; (b) formation of NSZs and sealing rings; (c) resorption. However, the assembly of podosomes which are critical for cell adhesion was not affected. L-plastin peptide-loaded PLGA-PEG nanocarriers have promising potential for the treatment of diseases associated with bone loss. Future studies will use this sustained release of peptide strategy to systematically suppress osteoclast bone resorption activity in vivo in mouse models demonstrating bone loss.
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Dual inhibition of ABCE1 and LCP1 by microRNA-96 results in an additive effect in breast cancer mouse model. Oncotarget 2019; 10:2086-2094. [PMID: 31007850 PMCID: PMC6459344 DOI: 10.18632/oncotarget.26747] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Accepted: 02/19/2019] [Indexed: 12/17/2022] Open
Abstract
MicroRNAs (miRNAs) are short non-coding RNAs that regulate the expression of target genes at the post-transcriptional level. Each miRNA can modulate multiple genes and, as a result, a single miRNA may have a profound effect on a specific biological pathway consisting of several of its target genes. Recent studies have indicated that specific miRNA signatures are correlated with tumor aggressiveness and clinical outcome in breast cancer. We previously demonstrated that miR-96 has a suppressive effect on breast cancer aggressiveness and that this effect was mediated by ABCE1 gene regulation. In this study we investigated whether other miR-96 regulated genes can enhance ABCE1’s anti-cancer effects. We identified one such gene – LCP1 – and proved its negative effect on breast cancer progression. Interestingly, dual inhibition of ABCE1 and LCP1 resulted in an additive effect on cancer cell migration, invasion, and proliferation. Furthermore, in vivo analysis of dual ABCE1 and LCP1 knockdown resulted in significant tumor growth inhibition, decreased metastatic activity, and contributed to survival compared to either gene, separately. This indicates that the combined downregulation of two miR-96 gene targets has an additive effect on reducing cancer aggressiveness. Overall, our work supports seeking more than one target in miRNA-based studies in order to enhance functional effects and better characterize the miRNA wide-spread activity.
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13
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Ten Broeke T, Honing H, Brandsma AM, Jacobino S, Bakema JE, Kanters D, van der Linden JAM, Bracke M, Koenderman L, Leusen JHW. FcαRI Dynamics Are Regulated by GSK-3 and PKCζ During Cytokine Mediated Inside-Out Signaling. Front Immunol 2019; 9:3191. [PMID: 30766540 PMCID: PMC6365424 DOI: 10.3389/fimmu.2018.03191] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 12/31/2018] [Indexed: 12/03/2022] Open
Abstract
IgA binding to FcαRI (CD89) is rapidly enhanced by cytokine induced inside-out signaling. Dephosphorylation of serine 263 in the intracellular tail of FcαRI by PP2A and PI3K activation are instrumental in this process. To further investigate these signaling pathways, we targeted downstream kinases of PI3K. Our experiments revealed that PI3K activates PKCζ, which subsequently inhibits GSK-3, a constitutively active kinase in resting cells and found here to be associated with FcαRI. We propose that GSK-3 maintains FcαRI in an inactive state at homeostatic conditions. Upon cytokine stimulation, GSK-3 is inactivated through a PI3K-PKCζ pathway, preventing the maintenance of phosphorylated inactive FcαRI. The concomitantly activated PP2A is then able to dephosphorylate and activate FcαRI. Moreover, FRAP and FLIP studies showed that FcαRI activation coincides with an increased mobile fraction of the receptor. This can enhance FcαRI valency and contribute to stronger avidity for IgA immune complexes. This tightly regulated inside-out signaling pathway allows leukocytes to respond rapidly and efficiently to their environment and could be exploited to enhance the efficacy of future IgA therapeutics.
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Affiliation(s)
- Toine Ten Broeke
- Laboratory of Translational Immunology, University Medical Center, Utrecht, Netherlands
| | - Henk Honing
- Department of Respiratory Medicine, University Medical Center, Utrecht, Netherlands
| | - Arianne M Brandsma
- Laboratory of Translational Immunology, University Medical Center, Utrecht, Netherlands
| | - Shamir Jacobino
- Laboratory of Translational Immunology, University Medical Center, Utrecht, Netherlands
| | - Jantine E Bakema
- Laboratory of Translational Immunology, University Medical Center, Utrecht, Netherlands.,Tumor Biology Section, Department of Otolaryngology, Head-Neck Surgery, VU University Medical Center, Amsterdam, Netherlands
| | - Deon Kanters
- Laboratory of Translational Immunology, University Medical Center, Utrecht, Netherlands.,Department of Respiratory Medicine, University Medical Center, Utrecht, Netherlands
| | - Jan A M van der Linden
- Laboratory of Translational Immunology, University Medical Center, Utrecht, Netherlands.,Department of Respiratory Medicine, University Medical Center, Utrecht, Netherlands
| | - Madelon Bracke
- Department of Pharmacoepidemiology and Pharmacotherapy, University Medical Center, Utrecht, Netherlands
| | - Leo Koenderman
- Laboratory of Translational Immunology, University Medical Center, Utrecht, Netherlands.,Department of Respiratory Medicine, University Medical Center, Utrecht, Netherlands
| | - Jeanette H W Leusen
- Laboratory of Translational Immunology, University Medical Center, Utrecht, Netherlands
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14
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Tseng HY, Samarelli AV, Kammerer P, Scholze S, Ziegler T, Immler R, Zent R, Sperandio M, Sanders CR, Fässler R, Böttcher RT. LCP1 preferentially binds clasped αMβ2 integrin and attenuates leukocyte adhesion under flow. J Cell Sci 2018; 131:jcs.218214. [PMID: 30333137 DOI: 10.1242/jcs.218214] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 09/07/2018] [Indexed: 12/13/2022] Open
Abstract
Integrins are α/β heterodimers that interconvert between inactive and active states. In the active state the α/β cytoplasmic domains recruit integrin-activating proteins and separate the transmembrane and cytoplasmic (TMcyto) domains (unclasped TMcyto). Conversely, in the inactive state the α/β TMcyto domains bind integrin-inactivating proteins, resulting in the association of the TMcyto domains (clasped TMcyto). Here, we report the isolation of integrin cytoplasmic tail interactors using either lipid bicelle-incorporated integrin TMcyto domains (α5, αM, αIIb, β1, β2 and β3 integrin TMcyto) or a clasped, lipid bicelle-incorporated αMβ2 TMcyto. Among the proteins found to preferentially bind clasped rather than the isolated αM and β2 subunits was L-plastin (LCP1, also known as plastin-2), which binds to and maintains the inactive state of αMβ2 integrin in vivo and thereby regulates leukocyte adhesion to integrin ligands under flow. Our findings offer a global view on cytoplasmic proteins interacting with different integrins and provide evidence for the existence of conformation-specific integrin interactors.
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Affiliation(s)
- Hui-Yuan Tseng
- Department of Molecular Medicine, Max Planck Institute for Biochemistry, 82152 Martinsried, Germany
| | - Anna V Samarelli
- Department of Molecular Medicine, Max Planck Institute for Biochemistry, 82152 Martinsried, Germany
| | - Patricia Kammerer
- Department of Molecular Medicine, Max Planck Institute for Biochemistry, 82152 Martinsried, Germany
| | - Sarah Scholze
- Department of Molecular Medicine, Max Planck Institute for Biochemistry, 82152 Martinsried, Germany
| | - Tilman Ziegler
- Department of Molecular Medicine, Max Planck Institute for Biochemistry, 82152 Martinsried, Germany
| | - Roland Immler
- Walter Brendel Center for Experimental Medicine, Ludwig-Maximilians-University, 81377 Munich, Germany
| | - Roy Zent
- Division of Nephrology, Department of Medicine, Vanderbilt University, Nashville, 37232 Tennessee, USA.,Department of Medicine, Veterans Affairs Medical Center, Nashville, 37232 Tennessee, USA
| | - Markus Sperandio
- Walter Brendel Center for Experimental Medicine, Ludwig-Maximilians-University, 81377 Munich, Germany
| | - Charles R Sanders
- Department of Biochemistry, Center for Structural Biology, and Institute of Chemical Biology, Vanderbilt University School of Medicine, Nashville, 37232 Tennessee, USA
| | - Reinhard Fässler
- Department of Molecular Medicine, Max Planck Institute for Biochemistry, 82152 Martinsried, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, 80802 Munich, Germany
| | - Ralph T Böttcher
- Department of Molecular Medicine, Max Planck Institute for Biochemistry, 82152 Martinsried, Germany .,DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, 80802 Munich, Germany
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15
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Chellaiah MA, Majumdar S, Aljohani H. Peptidomimetic inhibitors of L-plastin reduce the resorptive activity of osteoclast but not the bone forming activity of osteoblasts in vitro. PLoS One 2018; 13:e0204209. [PMID: 30248139 PMCID: PMC6152981 DOI: 10.1371/journal.pone.0204209] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 09/05/2018] [Indexed: 12/19/2022] Open
Abstract
Sealing ring formation is a requirement for osteoclast function. We have recently identified the role of an actin-bundling protein L-plastin in the assembly of nascent sealing zones (NSZs) at the early phase of sealing ring formation in osteoclasts. TNF-α signaling regulates this actin assembly by the phosphorylation of L-plastin on serine -5 and -7 residues at the amino-terminal end. These NSZs function as a core for integrin localization and coordinating integrin signaling required for maturation into fully functional sealing rings. Our goal is to elucidate the essential function of L-plastin phosphorylation in actin bundling, a process required for NSZs formation. The present study was undertaken to determine whether targeting serine phosphorylation of cellular L-plastin would be the appropriate approach to attenuate the formation of NSZs. Our approach is to use TAT-fused small molecular weight amino-terminal L-plastin peptides (10 amino acids) containing phospho- Ser-5 and Ser-7. We used peptides unsubstituted (P1) and substituted (P2- P4) at serine-to-alanine residues. Immunoblotting, actin staining, and dentine resorption analyses were done to determine cellular L-plastin phosphorylation, NSZ or sealing ring formation, and osteoclast function, respectively. Immunoblotting for bone formation markers, Alizarin red staining and alkaline phosphatase activity assay have been done to determine the effect of peptides on the mineralization process mediated by osteoblasts. Transduction of unsubstituted (P1) and substituted peptides at either Serine 5 or Serine 7 with Alanine (P3 and P4) demonstrated variable inhibitory effects on the phosphorylation of cellular L-plastin protein. Peptide P1 reduces the following processes substantially: 1) cellular L-plastin phosphorylation; 2) formation of nascent sealing zones and sealing rings; 3) bone resorption. Substitution of both Serine-5 and -7 with Alanine (P2) had no effects on the inhibitory activities described above. Furthermore, either the L-plastin (P1-P5) or (P6) control peptides had a little or no impact on the a) assembly/disassembly of podosomes and migration of osteoclasts; b) mineralization process mediated by osteoblasts in vitro. Small molecular weight peptidomimetics of L-plastin inhibits bone resorption by osteoclasts via attenuation of NSZ and sealing ring formation but not bone formation by osteoblasts in vitro. The L-plastin may be a valuable therapeutic target to treat and prevent diseases associated with bone loss without affecting bone formation.
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Affiliation(s)
- Meenakshi A. Chellaiah
- Department of Oncology and Diagnostic Sciences, School of Dentistry, University of Maryland, Baltimore, Maryland, United States of America
| | - Sunipa Majumdar
- Department of Oncology and Diagnostic Sciences, School of Dentistry, University of Maryland, Baltimore, Maryland, United States of America
| | - Hanan Aljohani
- Department of Oncology and Diagnostic Sciences, School of Dentistry, University of Maryland, Baltimore, Maryland, United States of America
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16
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Chellaiah MA, Ma T, Majumdar S. L-plastin phosphorylation regulates the early phase of sealing ring formation by actin bundling process in mouse osteoclasts. Exp Cell Res 2018; 372:73-82. [PMID: 30244178 DOI: 10.1016/j.yexcr.2018.09.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 09/05/2018] [Accepted: 09/19/2018] [Indexed: 10/28/2022]
Abstract
The process of sealing ring formation requires major actin filament reorganization. We previously demonstrated that an actin-bundling protein L-plastin has a role in the cross-linking of actin filaments into tight bundles and forms actin aggregates (denoted as nascent sealing zones). These nascent sealing zones mature into fully functional sealing rings. We have shown here that TNF-alpha signaling regulates the phosphorylation of serine-5 and -7 in L-plastin which increases the actin bundling capacity of L-plastin and hence the formation of nascent sealing zones in mouse osteoclasts. Using the TAT-mediated transduction method, we confirmed the role of L-plastin in nascent sealing zones formation at the early phase of the sealing ring assembly. Transduction of TAT-fused full-length L-plastin peptide significantly increases the number of nascent sealing zones and therefore sealing rings. But, transduction of amino-terminal L-plastin peptides consisting of the serine-5 and -7 reduces the formation of both nascent sealing zones and sealing rings. Therefore, bone resorption in vitro was reduced considerably. The decrease was associated with the selective inhibition of cellular L-plastin phosphorylation by the transduced peptides. Neither the formation of podosomes nor the migration was affected in these osteoclasts. Phosphorylation of L- plastin on serine 5 and -7 residues increases the F-actin bundling capacity. The significance of our studies stands on laying the groundwork for a better understanding of L-plastin as a potential regulator at the early phase of sealing ring formation and could be a new therapeutic target to treat bone loss.
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Affiliation(s)
- Meenakshi A Chellaiah
- Department of Oncology and Diagnostic Sciences Dental School, University of Maryland, Baltimore, Maryland.
| | - Tao Ma
- Department of Oncology and Diagnostic Sciences Dental School, University of Maryland, Baltimore, Maryland
| | - Sunipa Majumdar
- Department of Oncology and Diagnostic Sciences Dental School, University of Maryland, Baltimore, Maryland
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17
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Si M, Goodluck H, Zeng C, Pan S, Todd EM, Morley SC, Qin X, Mohan S, Xing W. LRRK1 regulation of actin assembly in osteoclasts involves serine 5 phosphorylation of L-plastin. J Cell Biochem 2018; 119:10351-10357. [PMID: 30136304 PMCID: PMC6218268 DOI: 10.1002/jcb.27377] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 07/02/2018] [Indexed: 12/11/2022]
Abstract
Mice with disruption of Lrrk1 and patients with nonfunctional mutant Lrrk1 exhibit severe osteopetrosis phenotypes because of osteoclast cytoskeletal dysfunction. To understand how Lrrk1 regulates osteoclast function by modulating cytoskeleton rearrangement, we examined the proteins that are differentially phosphorylated in wild‐type mice and Lrrk1‐deficient osteoclasts by metal affinity purification coupled liquid chromatography/mass spectrometry (LC/MS) analyses. One of the candidates that we identified by LC/MS is L‐plastin, an actin bundling protein. We found that phosphorylation of L‐plastin at serine (Ser) residues 5 was present in wild‐type osteoclasts but not in Lrrk1‐deficient cells. Western blot analyses with antibodies specific for Ser5 phosphorylated L‐plastin confirmed the reduced L‐plastin Ser5 phosphorylation in Lrrk1 knockout (KO) osteoclasts. micro computed tomography (Micro‐CT) analyses revealed that the trabecular bone volume of the distal femur was increased by 27% in the 16 to 21‐week‐old L‐plastin KO females as compared with the wild‐type control mice. The ratio of bone volume to tissue volume and connectivity density were increased by 44% and 47% (both P < 0.05), respectively, in L‐plastin KO mice. Our data suggest that targeted disruption of L‐plastin increases trabecular bone volume, and phosphorylation of Ser5 in L‐plastin in the Lrrk1 signaling pathway may in part contribute to actin assembly in mature osteoclasts.
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Affiliation(s)
- Mingjue Si
- Department of Radiology, Shanghai Ninth People's Hospital, Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China.,Department of Medicine, Loma Linda University, Loma Linda, California
| | - Helen Goodluck
- Musculoskeletal Disease Center, Jerry L. Pettis Memorial VA Medical Center, Loma Linda, California
| | - Canjun Zeng
- Musculoskeletal Disease Center, Jerry L. Pettis Memorial VA Medical Center, Loma Linda, California.,Department of Orthopedics, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China
| | - Songqin Pan
- Proteomics Core Facility, University of California, Riverside, California
| | - Elizabeth M Todd
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Sharon Celeste Morley
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri.,Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri
| | - Xuezhong Qin
- Department of Medicine, Loma Linda University, Loma Linda, California.,Musculoskeletal Disease Center, Jerry L. Pettis Memorial VA Medical Center, Loma Linda, California
| | - Subburaman Mohan
- Department of Medicine, Loma Linda University, Loma Linda, California.,Musculoskeletal Disease Center, Jerry L. Pettis Memorial VA Medical Center, Loma Linda, California
| | - Weirong Xing
- Department of Medicine, Loma Linda University, Loma Linda, California.,Musculoskeletal Disease Center, Jerry L. Pettis Memorial VA Medical Center, Loma Linda, California.,Department of Orthopedics, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China
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18
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Miao Y, Tipakornsaowapak T, Zheng L, Mu Y, Lewellyn E. Phospho-regulation of intrinsically disordered proteins for actin assembly and endocytosis. FEBS J 2018; 285:2762-2784. [PMID: 29722136 DOI: 10.1111/febs.14493] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 04/04/2018] [Accepted: 04/26/2018] [Indexed: 12/13/2022]
Abstract
Actin filament assembly contributes to the endocytic pathway pleiotropically, with active roles in clathrin-dependent and clathrin-independent endocytosis as well as subsequent endosomal trafficking. Endocytosis comprises a series of dynamic events, including the initiation of membrane curvature, bud invagination, vesicle abscission and subsequent vesicular transport. The ultimate success of endocytosis requires the coordinated activities of proteins that trigger actin polymerization, recruit actin-binding proteins (ABPs) and organize endocytic proteins (EPs) that promote membrane curvature through molecular crowding or scaffolding mechanisms. A particularly interesting phenomenon is that multiple EPs and ABPs contain a substantial percentage of intrinsically disordered regions (IDRs), which can contribute to protein coacervation and phase separation. In addition, intrinsically disordered proteins (IDPs) frequently contain sites for post-translational modifications (PTMs) such as phosphorylation, and these modifications exhibit a high preference for IDR residues [Groban ES et al. (2006) PLoS Comput Biol 2, e32]. PTMs are implicated in regulating protein function by modulating the protein conformation, protein-protein interactions and the transition between order and disorder states of IDPs. The molecular mechanisms by which IDRs of ABPs and EPs fine-tune actin assembly and endocytosis remain mostly unexplored and elusive. In this review, we analyze protein sequences of budding yeast EPs and ABPs, and discuss the potential underlying mechanisms for regulating endocytosis and actin assembly through the emerging concept of IDR-mediated protein multivalency, coacervation, and phase transition, with an emphasis on the phospho-regulation of IDRs. Finally, we summarize the current understanding of how these mechanisms coordinate actin cytoskeleton assembly and membrane curvature formation during endocytosis in budding yeast.
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Affiliation(s)
- Yansong Miao
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.,School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore
| | | | - Liangzhen Zheng
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Yuguang Mu
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Eric Lewellyn
- Department of Biology, Division of Natural Sciences, St Norbert College, De Pere, WI, USA
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19
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Targeted deletion of the zebrafish actin-bundling protein L-plastin (lcp1). PLoS One 2018; 13:e0190353. [PMID: 29293625 PMCID: PMC5749806 DOI: 10.1371/journal.pone.0190353] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2017] [Accepted: 12/13/2017] [Indexed: 01/09/2023] Open
Abstract
Regulation of the cytoskeleton is essential for cell migration in health and disease. Lymphocyte cytosolic protein 1 (lcp1, also called L-plastin) is a hematopoietic-specific actin-bundling protein that is highly conserved in zebrafish, mice and humans. In addition, L-plastin expression is documented as both a genetic marker and a cellular mechanism contributing to the invasiveness of tumors and transformed cell lines. Despite L-plastin’s role in both immunity and cancer, in zebrafish there are no direct studies of its function, and no mutant, knockout or reporter lines available. Using CRISPR-Cas9 genome editing, we generated null alleles of zebrafish lcp1 and examined the phenotypes of these fish throughout the life cycle. Our editing strategy used gRNA to target the second exon of lcp1, producing F0 mosaic fish that were outcrossed to wild types to confirm germline transmission. F1 heterozygotes were then sequenced to identify three unique null alleles, here called ‘Charlie’, ‘Foxtrot’ and ‘Lima’. In silico, each allele truncates the endogenous protein to less than 5% normal size and removes both essential actin-binding domains (ABD1 and ABD2). Although none of the null lines express detectable LCP1 protein, homozygous mutant zebrafish (-/-) can develop and reproduce normally, a finding consistent with that of the L-plastin null mouse (LPL -/-). However, such mice do have a profound immune defect when challenged by lung bacteria. Interestingly, we observed reduced long-term survival of zebrafish lcp1 -/- homozygotes (~30% below the expected numbers) in all three of our knockout lines, with greatest mortality corresponding to the period (4–6 weeks post-fertilization) when the innate immune system is functional, but the adaptive immune system is not yet mature. This suggests that null zebrafish may have reduced capacity to combat opportunistic infections, which are more easily transmissible in the aquatic environment. Overall, our novel mutant lines establish a sound genetic model and an enhanced platform for further studies of L-plastin gene function in hematopoiesis and cancer.
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20
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Mild traumatic brain injury induces memory deficits with alteration of gene expression profile. Sci Rep 2017; 7:10846. [PMID: 28883638 PMCID: PMC5589921 DOI: 10.1038/s41598-017-11458-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 08/24/2017] [Indexed: 01/11/2023] Open
Abstract
Repeated mild traumatic brain injury (rmTBI), the most common type of traumatic brain injuries, can result in neurological dysfunction and cognitive deficits. However, the molecular mechanisms and the long-term consequence of rmTBI remain elusive. In this study, we developed a modified rmTBI mouse model and found that rmTBI-induced transient neurological deficits and persistent impairments of spatial memory function. Furthermore, rmTBI mice had long-lasting detrimental effect on cognitive function, exhibiting memory deficits even 12 weeks after rmTBI. Microarray analysis of whole genome gene expression showed that rmTBI significantly altered the expression level of 87 genes which are involved in apoptosis, stress response, metabolism, and synaptic plasticity. The results indicate the potential mechanism underlying rmTBI-induced acute neurological deficits and its chronic effect on memory impairments. This study suggests that long-term monitoring and interventions for rmTBI individuals are essential for memory function recovery and reducing the risk of developing neurodegenerative diseases.
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21
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Schwebach CL, Agrawal R, Lindert S, Kudryashova E, Kudryashov DS. The Roles of Actin-Binding Domains 1 and 2 in the Calcium-Dependent Regulation of Actin Filament Bundling by Human Plastins. J Mol Biol 2017; 429:2490-2508. [PMID: 28694070 DOI: 10.1016/j.jmb.2017.06.021] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 06/30/2017] [Accepted: 06/30/2017] [Indexed: 01/04/2023]
Abstract
The actin cytoskeleton is a complex network controlled by a vast array of intricately regulated actin-binding proteins. Human plastins (PLS1, PLS2, and PLS3) are evolutionary conserved proteins that non-covalently crosslink actin filaments into tight bundles. Through stabilization of such bundles, plastins contribute, in an isoform-specific manner, to the formation of kidney and intestinal microvilli, inner ear stereocilia, immune synapses, endocytic patches, adhesion contacts, and invadosomes of immune and cancer cells. All plastins comprise an N-terminal Ca2+-binding regulatory headpiece domain followed by two actin-binding domains (ABD1 and ABD2). Actin bundling occurs due to simultaneous binding of both ABDs to separate actin filaments. Bundling is negatively regulated by Ca2+, but the mechanism of this inhibition remains unknown. In this study, we found that the bundling abilities of PLS1 and PLS2 were similarly sensitive to Ca2+ (pCa50 ~6.4), whereas PLS3 was less sensitive (pCa50 ~5.9). At the same time, all three isoforms bound to F-actin in a Ca2+-independent manner, suggesting that binding of only one of the ABDs is inhibited by Ca2+. Using limited proteolysis and mass spectrometry, we found that in the presence of Ca2+ the EF-hands of human plastins bound to an immediately adjacent sequence homologous to canonical calmodulin-binding peptides. Furthermore, our data from differential centrifugation, Förster resonance energy transfer, native electrophoresis, and chemical crosslinking suggest that Ca2+ does not affect ABD1 but inhibits the ability of ABD2 to interact with actin. A structural mechanism of signal transmission from Ca2+ to ABD2 through EF-hands remains to be established.
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Affiliation(s)
- Christopher L Schwebach
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA; Molecular, Cellular, and Developmental Biology Program, The Ohio State University, Columbus, OH 43210, USA
| | - Richa Agrawal
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
| | - Steffen Lindert
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
| | - Elena Kudryashova
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
| | - Dmitri S Kudryashov
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA; Molecular, Cellular, and Developmental Biology Program, The Ohio State University, Columbus, OH 43210, USA.
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22
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Witherel CE, Gurevich D, Collin JD, Martin P, Spiller KL. Host–Biomaterial Interactions in Zebrafish. ACS Biomater Sci Eng 2017; 4:1233-1240. [DOI: 10.1021/acsbiomaterials.6b00760] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Claire E. Witherel
- School of Biomedical Engineering, Science, and Health Systems, Drexel University, 3141 Chestnut Street, Philadelphia, Pennsylvania 19104 United States
| | | | - John D. Collin
- Bristol Royal Infirmary, University Hospitals Bristol NHS Trust, Upper Maudlin Street, Bristol BS2 8HW, United Kingdom
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23
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The Calcium-Dependent Switch Helix of L-Plastin Regulates Actin Bundling. Sci Rep 2017; 7:40662. [PMID: 28145401 PMCID: PMC5286426 DOI: 10.1038/srep40662] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 12/09/2016] [Indexed: 01/14/2023] Open
Abstract
L-plastin is a calcium-regulated actin-bundling protein that is expressed in cells of hematopoietic origin and in most metastatic cancer cells. These cell types are mobile and require the constant remodeling of their actin cytoskeleton, where L-plastin bundles filamentous actin. The calcium-dependent regulation of the actin-bundling activity of L-plastin is not well understood. We have used NMR spectroscopy to determine the solution structure of the EF-hand calcium-sensor headpiece domain. Unexpectedly, this domain does not bind directly to the four CH-domains of L-plastin. A novel switch helix is present immediately after the calcium-binding region and it binds tightly to the EF-hand motifs in the presence of calcium. We demonstrate that this switch helix plays a major role during actin-bundling. Moreover a peptide that competitively inhibits the association between the EF-hand motifs and the switch helix was shown to deregulate the actin-bundling activity of L-plastin. Overall, these findings may help to develop new drugs that target the L-plastin headpiece and interfere in the metastatic activity of cancer cells.
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24
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Wabnitz G, Balta E, Samstag Y. L-plastin regulates the stability of the immune synapse of naive and effector T-cells. Adv Biol Regul 2017; 63:107-114. [PMID: 27720134 DOI: 10.1016/j.jbior.2016.09.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 09/22/2016] [Accepted: 09/25/2016] [Indexed: 06/06/2023]
Abstract
T-cells need to be tightly regulated during their activation and effector phase to assure an appropriate defence against cancer or pathogens and - vice versa - to avoid autoimmune reactions. Regulatory signals are provided via the immune synapse between T-cells and antigen-presenting cells (APCs) or target cells. The stability and kinetics of immune synapse formation is critical for proper T-cell functions. It requires dynamic rearrangements of the actin cytoskeleton necessary for organized spatio-temporal redistribution of receptors and adhesion molecules. We identified glucocorticoid-sensitive phosphorylation of serine 5 on the actin-bundling protein L-plastin as one important signalling event for this regulation. Using imaging flow cytometry as well as confocal and super-resolution microscopy we showed that L-plastin relocalizes to the immune synapse upon antigen encounter, where it associates with the β2-subunit of LFA-1 (CD11a/CD18). Interfering with L-plastin expression or activation leads to a defective LFA-1 recruitment and unstable T-cell/APC contacts. Consequently, the lack of L-plastin diminishes T-cell activation, proliferation and proximal effector responses such as cytokine production. On the other hand, a pro-oxidative milieu leads to prolonged activation of L-plastin resulting in a stronger enrichment of LFA-1 in the cytolytic immune synapse. Concomitant stabilization of conjugates formed by cytotoxic T-cells (CTLs) and their target cells impairs the ability of CTLs to kill more than one target cells (serial killing), which de facto leads to a downregulation of T-cell cytotoxicity. Together, we demonstrate that activation and spacial distribution of L-plastin regulates the maturation and stability of activating and cytolytic immune synapses important for T-cell activation and effector functions.
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Affiliation(s)
- Guido Wabnitz
- Institute of Immunology, Section Molecular Immunology, Ruprecht-Karls-University Heidelberg, Im Neuenheimer Feld 305, D-69120 Heidelberg, Germany.
| | - Emre Balta
- Institute of Immunology, Section Molecular Immunology, Ruprecht-Karls-University Heidelberg, Im Neuenheimer Feld 305, D-69120 Heidelberg, Germany
| | - Yvonne Samstag
- Institute of Immunology, Section Molecular Immunology, Ruprecht-Karls-University Heidelberg, Im Neuenheimer Feld 305, D-69120 Heidelberg, Germany
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25
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Wałajtys-Rode E, Dzik JM. Monocyte/Macrophage: NK Cell Cooperation-Old Tools for New Functions. Results Probl Cell Differ 2017; 62:73-145. [PMID: 28455707 DOI: 10.1007/978-3-319-54090-0_5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Monocyte/macrophage and natural killer (NK) cells are partners from a phylogenetic standpoint of innate immune system development and its evolutionary progressive interaction with adaptive immunity. The equally conservative ways of development and differentiation of both invertebrate hemocytes and vertebrate macrophages are reviewed. Evolutionary conserved molecules occurring in macrophage receptors and effectors have been inherited by vertebrates after their common ancestor with invertebrates. Cytolytic functions of mammalian NK cells, which are rooted in immune cells of invertebrates, although certain NK cell receptors (NKRs) are mammalian new events, are characterized. Broad heterogeneity of macrophage and NK cell phenotypes that depends on surrounding microenvironment conditions and expression profiles of specific receptors and activation mechanisms of both cell types are discussed. The particular tissue specificity of macrophages and NK cells, as well as their plasticity and mechanisms of their polarization to different functional subtypes have been underlined. The chapter summarized studies revealing the specific molecular mechanisms and regulation of NK cells and macrophages that enable their highly specific cross-cooperation. Attention is given to the evolving role of human monocyte/macrophage and NK cell interaction in pathogenesis of hypersensitivity reaction-based disorders, including autoimmunity, as well as in cancer surveillance and progression.
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Affiliation(s)
- Elżbieta Wałajtys-Rode
- Faculty of Chemistry, Department of Drug Technology and Biotechnology, Warsaw University of Technology, Noakowskiego 3 Str, 00-664, Warsaw, Poland.
| | - Jolanta M Dzik
- Faculty of Agriculture and Biology, Department of Biochemistry, Warsaw University of Life Sciences-SGGW, Warsaw, Poland
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26
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Astell KR, Sieger D. Investigating microglia-brain tumor cell interactions in vivo in the larval zebrafish brain. Methods Cell Biol 2016; 138:593-626. [PMID: 28129859 DOI: 10.1016/bs.mcb.2016.10.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Glioblastoma is the most frequent and aggressive primary malignant brain tumor. Gliomas exhibit high genetic diversity in addition to complex and variable clinical features. Glioblastoma tumors are highly resistant to multimodal therapies and there is significant patient mortality within the first two years after prognosis. At present clinical treatments are palliative, not curative. Glioblastomas contain a high number of microglia and infiltrating macrophages, which are positively correlated with glioma grade and invasiveness. Microglia are the resident macrophages of the central nervous system. These cells constantly scan the brain and react promptly to any abnormality, removing detrimental factors and safeguarding the central nervous system against further damage. Microglia and macrophages that have colonized the glioblastoma display protumoral functions and promote tumor growth. The optically transparent zebrafish larva facilitates imaging of fluorescently labeled cells at high spatial and temporal resolution in vivo. It is therefore an excellent model to investigate microglia-glioma cell interactions at the early stages of tumor development. Here we provide several methods that can be used to study the early stages of microglia-glioma cell interactions in the zebrafish. We present a technique for the xenotransplantation of mammalian oncogenic cells into the zebrafish brain and provide advice for image capture and analysis.
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Affiliation(s)
- K R Astell
- University of Edinburgh, Edinburgh, United Kingdom
| | - D Sieger
- University of Edinburgh, Edinburgh, United Kingdom
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27
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Cook AB, Seifert AW. Beryllium nitrate inhibits fibroblast migration to disrupt epimorphic regeneration. Development 2016; 143:3491-3505. [PMID: 27578793 DOI: 10.1242/dev.134882] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 08/12/2016] [Indexed: 11/20/2022]
Abstract
Epimorphic regeneration proceeds with or without formation of a blastema, as observed for the limb and skin, respectively. Inhibition of epimorphic regeneration provides a means to interrogate the cellular and molecular mechanisms that regulate it. In this study, we show that exposing amputated limbs to beryllium nitrate disrupts blastema formation and causes severe patterning defects in limb regeneration. In contrast, exposing full-thickness skin wounds to beryllium only causes a delay in skin regeneration. By transplanting full-thickness skin from ubiquitous GFP-expressing axolotls to wild-type hosts, we demonstrate that beryllium inhibits fibroblast migration during limb and skin regeneration in vivo Moreover, we show that beryllium also inhibits cell migration in vitro using axolotl and human fibroblasts. Interestingly, beryllium did not act as an immunostimulatory agent as it does in Anurans and mammals, nor did it affect keratinocyte migration, proliferation or re-epithelialization, suggesting that the effect of beryllium is cell type-specific. While we did not detect an increase in cell death during regeneration in response to beryllium, it did disrupt cell proliferation in mesenchymal cells. Taken together, our data show that normal blastema organogenesis cannot occur without timely infiltration of local fibroblasts and highlights the importance of positional information to instruct pattern formation during regeneration. In contrast, non-blastemal-based skin regeneration can occur despite early inhibition of fibroblast migration and cell proliferation.
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Affiliation(s)
- Adam B Cook
- Department of Biology, University of Kentucky, Lexington, KY 40506, USA
| | - Ashley W Seifert
- Department of Biology, University of Kentucky, Lexington, KY 40506, USA
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28
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Miao Y, Han X, Zheng L, Xie Y, Mu Y, Yates JR, Drubin DG. Fimbrin phosphorylation by metaphase Cdk1 regulates actin cable dynamics in budding yeast. Nat Commun 2016; 7:11265. [PMID: 27068241 PMCID: PMC4832064 DOI: 10.1038/ncomms11265] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 03/07/2016] [Indexed: 12/15/2022] Open
Abstract
Actin cables, composed of actin filament bundles nucleated by formins, mediate intracellular transport for cell polarity establishment and maintenance. We previously observed that metaphase cells preferentially promote actin cable assembly through cyclin-dependent kinase 1 (Cdk1) activity. However, the relevant metaphase Cdk1 targets were not known. Here we show that the highly conserved actin filament crosslinking protein fimbrin is a critical Cdk1 target for actin cable assembly regulation in budding yeast. Fimbrin is specifically phosphorylated on threonine 103 by the metaphase cyclin–Cdk1 complex, in vivo and in vitro. On the basis of conformational simulations, we suggest that this phosphorylation stabilizes fimbrin's N-terminal domain, and modulates actin filament binding to regulate actin cable assembly and stability in cells. Overall, this work identifies fimbrin as a key target for cell cycle regulation of actin cable assembly in budding yeast, and suggests an underlying mechanism. Metaphase cells preferentially promote actin cable assembly through cyclin-dependent kinase 1 (Cdk1) activity. Here the authors identify fimbrin as one of the main metaphase Cdk1 targets for cell cycle regulation of actin cable assembly in budding yeast.
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Affiliation(s)
- Yansong Miao
- Department of Molecular and Cell Biology, University of California, Berkeley, California 94720-3202, USA.,School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore.,School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
| | - Xuemei Han
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Liangzhen Zheng
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Ying Xie
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
| | - Yuguang Mu
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - John R Yates
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037, USA
| | - David G Drubin
- Department of Molecular and Cell Biology, University of California, Berkeley, California 94720-3202, USA
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29
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Lommel MJ, Trairatphisan P, Gäbler K, Laurini C, Muller A, Kaoma T, Vallar L, Sauter T, Schaffner-Reckinger E. L-plastin Ser5 phosphorylation in breast cancer cells and in vitro is mediated by RSK downstream of the ERK/MAPK pathway. FASEB J 2015; 30:1218-33. [PMID: 26631483 DOI: 10.1096/fj.15-276311] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 11/16/2015] [Indexed: 12/20/2022]
Abstract
Deregulated cell migration and invasion are hallmarks of metastatic cancer cells. Phosphorylation on residue Ser5 of the actin-bundling protein L-plastin activates L-plastin and has been reported to be crucial for invasion and metastasis. Here, we investigate signal transduction leading to L-plastin Ser5 phosphorylation using 4 human breast cancer cell lines. Whole-genome microarray analysis comparing cell lines with different invasive capacities and corresponding variations in L-plastin Ser5 phosphorylation level revealed that genes of the ERK/MAPK pathway are differentially expressed. It is noteworthy that in vitro kinase assays showed that ERK/MAPK pathway downstream ribosomal protein S6 kinases α-1 (RSK1) and α-3 (RSK2) are able to directly phosphorylate L-plastin on Ser5. Small interfering RNA- or short hairpin RNA-mediated knockdown and activation/inhibition studies followed by immunoblot analysis and computational modeling confirmed that ribosomal S6 kinase (RSK) is an essential activator of L-plastin. Migration and invasion assays showed that RSK knockdown led to a decrease of up to 30% of migration and invasion of MDA-MB-435S cells. Although the presence of L-plastin was not necessary for migration/invasion of these cells, immunofluorescence assays illustrated RSK-dependent recruitment of Ser5-phosphorylated L-plastin to migratory structures. Altogether, we provide evidence that the ERK/MAPK pathway is involved in L-plastin Ser5 phosphorylation in breast cancer cells with RSK1 and RSK2 kinases able to directly phosphorylate L-plastin residue Ser5.
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Affiliation(s)
- Maiti J Lommel
- *Laboratory of Cytoskeleton and Cell Plasticity and Systems Biology Group, Life Sciences Research Unit, University of Luxembourg, Luxembourg City, Luxembourg; and Genomics Research Unit, Luxembourg Institute of Health, Luxembourg City, Luxembourg
| | - Panuwat Trairatphisan
- *Laboratory of Cytoskeleton and Cell Plasticity and Systems Biology Group, Life Sciences Research Unit, University of Luxembourg, Luxembourg City, Luxembourg; and Genomics Research Unit, Luxembourg Institute of Health, Luxembourg City, Luxembourg
| | - Karoline Gäbler
- *Laboratory of Cytoskeleton and Cell Plasticity and Systems Biology Group, Life Sciences Research Unit, University of Luxembourg, Luxembourg City, Luxembourg; and Genomics Research Unit, Luxembourg Institute of Health, Luxembourg City, Luxembourg
| | - Christina Laurini
- *Laboratory of Cytoskeleton and Cell Plasticity and Systems Biology Group, Life Sciences Research Unit, University of Luxembourg, Luxembourg City, Luxembourg; and Genomics Research Unit, Luxembourg Institute of Health, Luxembourg City, Luxembourg
| | - Arnaud Muller
- *Laboratory of Cytoskeleton and Cell Plasticity and Systems Biology Group, Life Sciences Research Unit, University of Luxembourg, Luxembourg City, Luxembourg; and Genomics Research Unit, Luxembourg Institute of Health, Luxembourg City, Luxembourg
| | - Tony Kaoma
- *Laboratory of Cytoskeleton and Cell Plasticity and Systems Biology Group, Life Sciences Research Unit, University of Luxembourg, Luxembourg City, Luxembourg; and Genomics Research Unit, Luxembourg Institute of Health, Luxembourg City, Luxembourg
| | - Laurent Vallar
- *Laboratory of Cytoskeleton and Cell Plasticity and Systems Biology Group, Life Sciences Research Unit, University of Luxembourg, Luxembourg City, Luxembourg; and Genomics Research Unit, Luxembourg Institute of Health, Luxembourg City, Luxembourg
| | - Thomas Sauter
- *Laboratory of Cytoskeleton and Cell Plasticity and Systems Biology Group, Life Sciences Research Unit, University of Luxembourg, Luxembourg City, Luxembourg; and Genomics Research Unit, Luxembourg Institute of Health, Luxembourg City, Luxembourg
| | - Elisabeth Schaffner-Reckinger
- *Laboratory of Cytoskeleton and Cell Plasticity and Systems Biology Group, Life Sciences Research Unit, University of Luxembourg, Luxembourg City, Luxembourg; and Genomics Research Unit, Luxembourg Institute of Health, Luxembourg City, Luxembourg
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30
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Yıldırım C, Favre J, Weijers EM, Fontijn RD, van Wijhe MH, van Vliet SJ, Boon RA, Koolwijk P, van der Pouw Kraan TCTM, Horrevoets AJG. IFN-β affects the angiogenic potential of circulating angiogenic cells by activating calpain 1. Am J Physiol Heart Circ Physiol 2015; 309:H1667-78. [DOI: 10.1152/ajpheart.00810.2014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Accepted: 09/01/2015] [Indexed: 01/15/2023]
Abstract
Circulating angiogenic cells (CACs) are monocyte-derived cells with endothelial characteristics, which contribute to both angiogenesis and arteriogenesis in a paracrine way. Interferon-β (IFN-β) is known to inhibit these divergent processes in animals and patients. We hypothesized that IFN-β might act by affecting the differentiation and function of CACs. CACs were cultured from peripheral blood mononuclear cells and phenotypically characterized by surface expression of monocytic and endothelial markers. IFN-β significantly reduced the number of CACs by 18–64%. Apoptosis was not induced by IFN-β, neither in mononuclear cells during differentiation, nor after maturation to CACs. Rather, IFN-β impaired adhesion to, and spreading on, fibronectin, which was dependent on α5β1 (VLA-5)-integrin. IFN-β affected the function of VLA-5 in mature CACs, leading to rounding and detachment of cells, by induction of calpain 1 activity. Cell rounding and detachment was completely reversed by inhibition of calpain 1 activity in mature CACs. During in vitro capillary formation, CAC addition and calpain 1 inhibition enhanced sprouting of endothelial cells to a comparable extent, but were not sufficient to rescue tube formation in the presence of IFN-β. We show that the IFN-β-induced reduction of the numbers of in vitro differentiated CACs is based on activation of calpain 1, resulting in an attenuated adhesion to extracellular matrix proteins via VLA-5. In vivo, this could lead to inhibition of vessel formation due to reduction of the locally recruited CAC numbers and their paracrine angiogenic factors.
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Affiliation(s)
- Cansu Yıldırım
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, Amsterdam, The Netherlands
| | - Julie Favre
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, Amsterdam, The Netherlands
| | - Ester M. Weijers
- Department of Physiology, Institute for Cardiovascular Research (ICaR-VU), VU University Medical Center, Amsterdam, The Netherlands; and
| | - Ruud D. Fontijn
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, Amsterdam, The Netherlands
| | - Michiel H. van Wijhe
- Department of Physiology, Institute for Cardiovascular Research (ICaR-VU), VU University Medical Center, Amsterdam, The Netherlands; and
| | - Sandra J. van Vliet
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, Amsterdam, The Netherlands
| | - Reinier A. Boon
- Institute for Cardiovascular Regeneration, Centre for Molecular Medicine, Goethe University, Frankfurt, Germany
| | - Pieter Koolwijk
- Department of Physiology, Institute for Cardiovascular Research (ICaR-VU), VU University Medical Center, Amsterdam, The Netherlands; and
| | | | - Anton J. G. Horrevoets
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, Amsterdam, The Netherlands
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31
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Li N, Mruk DD, Wong CKC, Lee WM, Han D, Cheng CY. Actin-bundling protein plastin 3 is a regulator of ectoplasmic specialization dynamics during spermatogenesis in the rat testis. FASEB J 2015; 29:3788-805. [PMID: 26048141 DOI: 10.1096/fj.14-267997] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 05/18/2015] [Indexed: 12/13/2022]
Abstract
Ectoplasmic specialization (ES) is an actin-rich adherens junction in the seminiferous epithelium of adult mammalian testes. ES is restricted to the Sertoli-spermatid (apical ES) interface, as well as the Sertoli cell-cell (basal ES) interface at the blood-testis barrier (BTB). ES is typified by the presence of an array of bundles of actin microfilaments near the Sertoli cell plasma membrane. These actin microfilament bundles require rapid debundling to convert them from a bundled to branched/unbundled configuration and vice versa to confer plasticity to support the transport of 1) spermatids in the adluminal compartment and 2) preleptotene spermatocytes at the BTB while maintaining cell adhesion. Plastin 3 is one of the plastin family members abundantly found in yeast, plant and animal cells that confers actin microfilaments their bundled configuration. Herein, plastin 3 was shown to be a component of the apical and basal ES in the rat testis, displaying spatiotemporal expression during the epithelial cycle. A knockdown (KD) of plastin 3 in Sertoli cells by RNA interference using an in vitro model to study BTB function showed that a transient loss of plastin 3 perturbed the Sertoli cell tight junction-permeability barrier, mediated by changes in the localization of basal ES proteins N-cadherin and β-catenin. More importantly, these changes were the result of an alteration of the actin microfilaments, converting from their bundled to branched configuration when examined microscopically, and validated by biochemical assays that quantified actin-bundling and polymerization activity. Moreover, these changes were confirmed by studies in vivo by plastin 3 KD in the testis in which mis-localization of N-cadherin and β-catenin was also detected at the BTB, concomitant with defects in the transport of spermatids and phagosomes and a disruption of cell adhesion most notably in elongated spermatids due to a loss of actin-bundling capability at the apical ES, which in turn affected localization of adhesion protein complexes at the site. In summary, plastin 3 is a regulator of actin microfilament bundles at the ES in which it dictates the configuration of the filamentous actin network by assuming either a bundled or unbundled/branched configuration via changes in its spatiotemporal expression during the epithelial cycle.
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Affiliation(s)
- Nan Li
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Dolores D Mruk
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Chris K C Wong
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Will M Lee
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Daishu Han
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - C Yan Cheng
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
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32
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Öztürk VÖ, Emingil G, Osterwalder V, Bostanci N. The actin-bundling protein L-plastin: a novel local inflammatory marker associated with periodontitis. J Periodontal Res 2014; 50:337-46. [DOI: 10.1111/jre.12212] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/23/2014] [Indexed: 12/11/2022]
Affiliation(s)
- V. Ö. Öztürk
- Oral Translational Research; Institute of Oral Biology; Center of Dental Medicine; University of Zürich; Zürich Switzerland
- Department of Periodontology; School of Dentistry; Ege University; İzmir Turkey
| | - G. Emingil
- Department of Periodontology; School of Dentistry; Ege University; İzmir Turkey
| | - V. Osterwalder
- Oral Translational Research; Institute of Oral Biology; Center of Dental Medicine; University of Zürich; Zürich Switzerland
| | - N. Bostanci
- Oral Translational Research; Institute of Oral Biology; Center of Dental Medicine; University of Zürich; Zürich Switzerland
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33
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Toyooka K, Liu F, Ishii M, Saito S, Kirikae T, Asano Y, Shinomiya H. Generation and Characterization of Monoclonal Antibodies That Specifically Recognize p65/L-Plastin Isoform but Not T-Plastin Isoform. Biosci Biotechnol Biochem 2014; 70:1402-7. [PMID: 16794320 DOI: 10.1271/bbb.50659] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The 65-kDa protein (p65) was previously identified as a phosphorylated protein in activated macrophages, and has turned out to be a member of a plastin protein family characterized by a series of Ca(2+)-, calmodulin-, and beta-actin-binding domains. In mice, two isoforms, p65/L-plastin and T-plastin, have so far been identified; p65/L-plastin is expressed in hemopoietic cells and cancer cells, and T-plastin in solid tissue cells. We generated monoclonal antibodies to p65/L-plastin, examined the isoform-specificity by using recombinant (r) T-plastin, and found that the antibodies were specific for rp65/L-plastin, whereas immune sera to rp65/L-plastin showed cross-reactions to rT-plastin. One of the antibodies, p65-7B5, was demonstrated to react to native p65/L-plastin by Western blot, flow cytometric, and immunohistochemical analysis. Furthermore, p65-7B5 has made it possible to detect p65/L-plastin-expressing cells in tissues where T-plastin is abundantly expressed. These reagents and procedures should provide specific tools to investigate the role of p65/L-plastin in leukocytes.
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34
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Zhong Y, Byrd JC, Dubovsky JA. The B-cell receptor pathway: a critical component of healthy and malignant immune biology. Semin Hematol 2014; 51:206-18. [PMID: 25048784 DOI: 10.1053/j.seminhematol.2014.05.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The pathogenesis and progression of normal B-cell development to malignant transformation of chronic lymphocytic leukemia (CLL) is still poorly understood and has hampered attempts to develop targeted therapeutics for this disease. The dependence of CLL cells on B-cell receptor signaling has fostered a new area of basic and therapeutic research interest. In particular, identification of the dependence of CLL cells on both phosphatidylinositol 3-kinase delta and Bruton's tyrosine kinase signaling for survival and proliferation has come forth through well-performed preclinical studies and subsequent trials demonstrating dramatic efficacy. This review outlines essential components of B-cell receptor signaling and briefly addresses therapeutics that are emerging to target these in patients with CLL and related lymphoid malignancies.
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Affiliation(s)
- Yiming Zhong
- Division of Hematology, Department of Internal Medicine, The Ohio State University, Columbus, OH
| | - John C Byrd
- Division of Hematology, Department of Internal Medicine, The Ohio State University, Columbus, OH; Division of Medicinal Chemistry, College of Pharmacy, The Ohio State University, Columbus, OH
| | - Jason A Dubovsky
- Division of Hematology, Department of Internal Medicine, The Ohio State University, Columbus, OH.
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35
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Taylor A, Tang W, Bruscia EM, Zhang PX, Lin A, Gaines P, Wu D, Halene S. SRF is required for neutrophil migration in response to inflammation. Blood 2014; 123:3027-36. [PMID: 24574460 PMCID: PMC4014845 DOI: 10.1182/blood-2013-06-507582] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Accepted: 02/10/2014] [Indexed: 11/20/2022] Open
Abstract
Serum response factor (SRF) is a ubiquitously expressed transcription factor and master regulator of the actin cytoskeleton. We have previously shown that SRF is essential for megakaryocyte maturation and platelet formation and function. Here we elucidate the role of SRF in neutrophils, the primary defense against infections. To study the effect of SRF loss in neutrophils, we crossed Srf(fl/fl) mice with select Cre-expressing mice and studied neutrophil function in vitro and in vivo. Despite normal neutrophil numbers, neutrophil function is severely impaired in Srf knockout (KO) neutrophils. Srf KO neutrophils fail to polymerize globular actin to filamentous actin in response to N-formyl-methionine-leucine-phenylalanine, resulting in significantly disrupted cytoskeletal remodeling. Srf KO neutrophils fail to migrate to sites of inflammation in vivo and along chemokine gradients in vitro. Polarization in response to cytokine stimuli is absent and Srf KO neutrophils show markedly reduced adhesion. Integrins play an essential role in cellular adhesion, and although integrin expression levels are maintained with loss of SRF, integrin activation and trafficking are disrupted. Migration and cellular adhesion are essential for normal cell function, but also for malignant processes such as metastasis, underscoring an essential function for SRF and its pathway in health and disease.
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Affiliation(s)
- Ashley Taylor
- Section of Hematology, Department of Internal Medicine and Yale Comprehensive Cancer Center
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36
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Serrano-Pertierra E, Cernuda-Morollón E, Brdička T, Hoøejši V, López-Larrea C. L-plastin is involved in NKG2D recruitment into lipid rafts and NKG2D-mediated NK cell migration. J Leukoc Biol 2014; 96:437-45. [PMID: 24803550 DOI: 10.1189/jlb.2a1013-564r] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Membrane rafts are microdomains of the plasma membrane that have multiple biological functions. The involvement of these structures in the biology of T cells, namely in signal transduction by the TCR, has been widely studied. However, the role of membrane rafts in immunoreceptor signaling in NK cells is less well known. We studied the distribution of the activating NKG2D receptor in lipid rafts by isolating DRMs in a sucrose density gradient or by raft fractionation by β-OG-selective solubility in the NKL cell line. We found that the NKG2D-DAP10 complex and pVav are recruited into rafts upon receptor stimulation. Qualitative proteomic analysis of these fractions showed that the actin cytoskeleton is involved in this process. In particular, we found that the actin-bundling protein L-plastin plays an important role in the clustering of NKG2D into lipid rafts. Moreover, coengagement of the inhibitory receptor NKG2A partially disrupted NKG2D recruitment into rafts. Furthermore, we demonstrated that L-plastin participates in NKG2D-mediated inhibition of NK cell chemotaxis.
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Affiliation(s)
| | - Eva Cernuda-Morollón
- Neurology Departments, Hospital Universitario Central de Asturias, Oviedo, Asturias, Spain
| | - Tomáš Brdička
- Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic; and
| | - Václav Hoøejši
- Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic; and
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37
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Riplinger SM, Wabnitz GH, Kirchgessner H, Jahraus B, Lasitschka F, Schulte B, van der Pluijm G, van der Horst G, Hämmerling GJ, Nakchbandi I, Samstag Y. Metastasis of prostate cancer and melanoma cells in a preclinical in vivo mouse model is enhanced by L-plastin expression and phosphorylation. Mol Cancer 2014; 13:10. [PMID: 24438191 PMCID: PMC3899628 DOI: 10.1186/1476-4598-13-10] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2013] [Accepted: 01/08/2014] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Tumor cell migration and metastasis require dynamic rearrangements of the actin cytoskeleton. Interestingly, the F-actin cross-linking and stabilizing protein L-plastin, originally described as a leukocyte specific protein, is aberrantly expressed in several non-hematopoietic malignant tumors. Therefore, it has been discussed as a tumor marker. However, systematic in vivo analyses of the functional relevance of L-plastin for tumor cell metastasis were so far lacking. METHODS We investigated the relevance of L-plastin expression and phosphorylation by ectopical expression of L-plastin in human melanoma cells (MV3) and knock-down of endogenous L-plastin in prostate cancer (PC3M). The growth and metastatic potential of tumor cells expressing no L-plastin, phosphorylatable or non-phosphorylatable L-plastin was analyzed in a preclinical mouse model after subcutaneous and intracardial injection of the tumor cells. RESULTS Knock-down of endogenous L-plastin in human prostate carcinoma cells led to reduced tumor cell growth and metastasis. Vice versa, and in line with these findings, ectopic expression of L-plastin in L-plastin negative melanoma cells significantly increased the number of metastases. Strikingly, the metastasis promoting effect of L-plastin was not observed if a non-phosphorylatable L-plastin mutant was expressed. CONCLUSIONS Our data provide the first in vivo evidence that expression of L-plastin promotes tumor metastasis and, importantly, that this effect depends on an additionally required phosphorylation of L-plastin. In conclusion, these findings imply that for determining the importance of tumor-associated proteins like L-plastin a characterization of posttranslational modifications is indispensable.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Yvonne Samstag
- Institute for Immunology, Ruprecht-Karls-University, Heidelberg, Germany.
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Krainer EC, Ouderkirk JL, Miller EW, Miller MR, Mersich AT, Blystone SD. The multiplicity of human formins: Expression patterns in cells and tissues. Cytoskeleton (Hoboken) 2013; 70:424-38. [PMID: 23629878 DOI: 10.1002/cm.21113] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Accepted: 04/17/2013] [Indexed: 11/06/2022]
Abstract
Formins are actin-binding proteins conserved across species from plants to humans. The formin family is defined by their common formin homology (FH2) domains. The 15 distinct human formins are involved in a broad range of cellular functions, including cell adhesion, cytokinesis, cell polarity, and cell morphogenesis. Their commonality is actin polymerization activity inherent to FH2 domains. Although still requiring much study, biochemical activity of formins has been carefully described. In contrast, much less is known of their activities in complex living systems. With the diversity of the formin family and the actin structures that they affect, an extensive future of study beckons. In this study, we report the expression level of all 15 formins in 22 different human cell and tissue types using quantitative real-time PCR. Identification of major themes in formin expression and documentation of expression profiles should facilitate the cellular study of formins.
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Affiliation(s)
- Elisabeth C Krainer
- Department of Cell and Developmental Biology, SUNY Upstate Medical University, Syracuse, New York, 13210
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Langereis JD, Koenderman L, Huttenlocher A, Ulfman LH. Gelsolin expression increases β1 -integrin affinity and L1210 cell adhesion. Cytoskeleton (Hoboken) 2013; 70:385-93. [PMID: 23595955 DOI: 10.1002/cm.21112] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2012] [Revised: 03/19/2013] [Accepted: 04/08/2013] [Indexed: 01/13/2023]
Abstract
Integrins are functionally regulated by "inside-out" signaling, in that stimulus-induced signaling pathways act on the intracellular integrin tail to regulate the activity of the receptor on the outside. Both a change in conformation (affinity) and clustering (avidity/valency) of the receptors occurs, but the mechanisms that regulate inside out signaling are not completely understood. Previously, we identified gelsolin in a proteomics screen to identify proteins involved in inside-out control of integrins using the lymphocytic leukemia cell line L1210. Furthermore, we showed that gelsolin was involved in affinity regulation of β1 -integrins in the leukemic cell line U937. Here, we examined how gelsolin regulates β1 -integrin affinity in the leukemia cell line L1210. We show that gelsolin is mainly expressed at the cell membrane and is present near β1 -integrins. The role for actin polymerization in integrin affinity regulation was examined using the actin modulating agent jasplakinolide, which decreased β1 -integrin affinity. Similarly, knock-down of gelsolin in L1210 cells also decreased β1 -integrin affinity and cell adhesion to collagen. These data suggest that increased actin polymerization through gelsolin regulates β1 -integrin affinity and cell adhesion.
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Affiliation(s)
- Jeroen D Langereis
- Department of Respiratory Medicine, University Medical Center Utrecht, Utrecht, the Netherlands
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40
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Han NY, Choi W, Park JM, Kim EH, Lee H, Hahm KB. Label-free quantification for discovering novel biomarkers in the diagnosis and assessment of disease activity in inflammatory bowel disease. J Dig Dis 2013; 14:166-74. [PMID: 23320753 DOI: 10.1111/1751-2980.12035] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE No distinctive biomarkers capable of discriminating between ulcerative colitis (UC) and Crohn's disease (CD) have yet been found. In this study, we aimed to discover these biomarkers by using advanced label-free quantification technology for proteomes. METHODS Biomarker protein expressions of colonic tissues of Korean IBD patients and controls were determined using label-free quantification to compare the protein profiles of colonic mucosa in three individuals with normal colonic tissue, four patients with UC, three with CD and two with inflammatory polyps related to UC. A computational framework and tools for discovery-based liquid chromatography-tandem mass spectrometry proteomics was applied to draw the biomarkers. RESULTS In total, 339 proteins were identified in normal sample group, 217 and 283 proteins in active and inactive UC, 345 and 366 proteins in active and inactive CD and 392 proteins in inflammatory polyps related to UC, respectively. The findings were reproducible. A Corra analysis led to the discovery of 27 potential biomarkers in UC, 37 biomarkers relevant to CD and 11 proteins commonly associated with IBD. Three novel proteins, PRG2, LCP1 and PSME1 were identified as biomarkers signifying active CD. CONCLUSION This is the first study to apply label-free quantification for discovering biomarkers in patients with different types and stages of IBD, providing additional insights for revealing the molecular pathogenesis of IBD as well as protein biomarkers of IBD predicting responses to treatment.
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Affiliation(s)
- Na-Young Han
- Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon, Korea
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41
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De Clercq S, Zwaenepoel O, Martens E, Vandekerckhove J, Guillabert A, Gettemans J. Nanobody-induced perturbation of LFA-1/L-plastin phosphorylation impairs MTOC docking, immune synapse formation and T cell activation. Cell Mol Life Sci 2013; 70:909-22. [PMID: 23001012 PMCID: PMC11113607 DOI: 10.1007/s00018-012-1169-0] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Revised: 08/24/2012] [Accepted: 09/11/2012] [Indexed: 02/05/2023]
Abstract
The T cell integrin receptor LFA-1 orchestrates adhesion between T cells and antigen-presenting cells (APCs), resulting in formation of a contact zone known as the immune synapse (IS) which is supported by the cytoskeleton. L-plastin is a leukocyte-specific actin bundling protein that rapidly redistributes to the immune synapse following T cell-APC engagement. We used single domain antibodies (nanobodies, derived from camelid heavy-chain only antibodies) directed against functional and structural modules of L-plastin to investigate its contribution to formation of an immune synapse between Raji cells and human peripheral blood mononuclear cells or Jurkat T cells. Nanobodies that interact either with the EF hands or the actin binding domains of L-plastin both trapped L-plastin in an inactive conformation, causing perturbation of IS formation, MTOC docking towards the plasma membrane, T cell proliferation and IL-2 secretion. Both nanobodies delayed Ser(5) phosphorylation of L-plastin which is required for enhanced bundling activity. Moreover, one nanobody delayed LFA-1 phosphorylation, reduced the association between LFA-1 and L-plastin and prevented LFA-1 enrichment at the IS. Our findings reveal subtle mechanistic details that are difficult to attain by conventional means and show that L-plastin contributes to immune synapse formation at distinct echelons.
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Affiliation(s)
- Sarah De Clercq
- Department of Medical Protein Research, VIB, 9000 Ghent, Belgium
- Faculty of Medicine and Health Sciences, Ghent University, A. Baertsoenkaai 3, 9000 Ghent, Belgium
| | - Olivier Zwaenepoel
- Department of Medical Protein Research, VIB, 9000 Ghent, Belgium
- Faculty of Medicine and Health Sciences, Ghent University, A. Baertsoenkaai 3, 9000 Ghent, Belgium
| | - Evelien Martens
- Department of Medical Protein Research, VIB, 9000 Ghent, Belgium
- Faculty of Medicine and Health Sciences, Ghent University, A. Baertsoenkaai 3, 9000 Ghent, Belgium
| | - Joël Vandekerckhove
- Department of Medical Protein Research, VIB, 9000 Ghent, Belgium
- Faculty of Medicine and Health Sciences, Ghent University, A. Baertsoenkaai 3, 9000 Ghent, Belgium
| | - Aude Guillabert
- Department of Medical Protein Research, VIB, 9000 Ghent, Belgium
- Faculty of Medicine and Health Sciences, Ghent University, A. Baertsoenkaai 3, 9000 Ghent, Belgium
| | - Jan Gettemans
- Department of Medical Protein Research, VIB, 9000 Ghent, Belgium
- Faculty of Medicine and Health Sciences, Ghent University, A. Baertsoenkaai 3, 9000 Ghent, Belgium
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Genetic programs expressed in resting and IL-4 alternatively activated mouse and human macrophages: similarities and differences. Blood 2013; 121:e57-69. [PMID: 23293084 DOI: 10.1182/blood-2012-06-436212] [Citation(s) in RCA: 375] [Impact Index Per Article: 34.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The molecular repertoire of macrophages in health and disease can provide novel biomarkers for diagnosis, prognosis, and treatment. Th2-IL-4–activated macrophages (M2) have been associated with important diseases in mice, yet no specific markers are available for their detection in human tissues. Although mouse models are widely used for macrophage research, translation to the human can be problematic and the human macrophage system remains poorly described. In the present study, we analyzed and compared the transcriptome and proteome of human and murine macrophages under resting conditions (M0) and after IL-4 activation (M2). We provide a resource for tools enabling macrophage detection in human tissues by identifying a set of 87 macrophage-related genes. Furthermore, we extend current understanding of M2 activation in different species and identify Transglutaminase 2 as a conserved M2 marker that is highly expressed by human macrophages and monocytes in the prototypic Th2 pathology asthma.
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Shipman M, Lubick K, Fouchard D, Guram R, Grieco P, Jutila M, Dratz EA. Proteomic and systems biology analysis of monocytes exposed to securinine, a GABA(A) receptor antagonist and immune adjuvant. PLoS One 2012; 7:e41278. [PMID: 23028424 PMCID: PMC3441550 DOI: 10.1371/journal.pone.0041278] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Accepted: 06/19/2012] [Indexed: 11/18/2022] Open
Abstract
Securinine, a GABA(A) receptor antagonist, has been reported to enhance monocyte cell killing of Coxiella burnetii without obvious adverse effects in vivo. We employed multiplex 2D gel electrophoresis using Zdyes, a new generation of covalently linked fluorescent differential protein detection dyes to analyze changes in the monocyte proteome in response to Securinine. Securinine antagonism of GABA(A) receptors triggers the activation of p38. We used the differential protein expression results to guide a search of the literature and network analysis software to construct a systems biology model of the effect of Securinine on monocytes. The model suggests that various metabolic modulators (fatty acid binding protein 5, inosine 5'-monophosphate dehydrogenase, and thioredoxin) are at least partially reshaping the metabolic landscape within the monocytes. The actin bundling protein L-plastin, and the Ca(2+) binding protein S100A4 also appear to have important roles in the immune response stimulated by Securinine. Fatty acid binding protein 5 (FABP5) may be involved in effecting lipid raft composition, inflammation, and hormonal regulation of monocytes, and the model suggests that FABP5 may be a central regulator of metabolism in activated monocytes. The model also suggests that the heat shock proteins have a significant impact on the monocyte immune response. The model provides a framework to guide future investigations into the mechanisms of Securinine action and with elaboration may help guide development of new types of immune adjuvants.
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Affiliation(s)
- Matt Shipman
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana, United States of America.
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Montresor A, Toffali L, Constantin G, Laudanna C. Chemokines and the signaling modules regulating integrin affinity. Front Immunol 2012; 3:127. [PMID: 22654882 PMCID: PMC3360201 DOI: 10.3389/fimmu.2012.00127] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2012] [Accepted: 05/03/2012] [Indexed: 01/05/2023] Open
Abstract
Integrin-mediated adhesion is a general concept referring to a series of adhesive phenomena including tethering–rolling, affinity, valency, and binding stabilization altogether controlling cell avidity (adhesiveness) for the substrate. Arrest chemokines modulate each aspect of integrin activation, although integrin affinity regulation has been recognized as the prominent event in rapid leukocyte arrest induced by chemokines. A variety of inside-out and outside-in signaling mechanisms have been related to the process of integrin-mediated adhesion in different cellular models, but only few of them have been clearly contextualized to rapid integrin affinity modulation by arrest chemokines in primary leukocytes. Complex signaling processes triggered by arrest chemokines and controlling leukocyte integrin activation have been described for ras-related rap and for rho-related small GTPases. We summarize the role of rap and rho small GTPases in the regulation of rapid integrin affinity in primary leukocytes and provide a modular view of these pro-adhesive signaling events. A potential, albeit still speculative, mechanism of rho-mediated regulation of cytoskeletal proteins controlling the last step of integrin activation is also discussed. We also discuss data suggesting a functional integration between the rho- and rap-modules of integrin activation. Finally we examine the universality of signaling mechanisms regulating integrin triggering by arrest chemokines.
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Affiliation(s)
- Alessio Montresor
- Division of General Pathology, Department of Pathology, University of Verona Verona, Italy
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45
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Chan HH, Rahim ZHA, Jessie K, Hashim OH, Taiyeb-Ali TB. Salivary proteins associated with periodontitis in patients with Type 2 diabetes mellitus. Int J Mol Sci 2012; 13:4642-4654. [PMID: 22606001 PMCID: PMC3344237 DOI: 10.3390/ijms13044642] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2012] [Revised: 03/23/2012] [Accepted: 03/31/2012] [Indexed: 02/07/2023] Open
Abstract
The objective of this study was to investigate the salivary proteins that are associated with periodontitis in patients with Type 2 diabetes mellitus (T2DM). Volunteers for the study were patients from the Diabetic Unit, University of Malaya Medical Centre, whose periodontal status was determined. The diabetic volunteers were divided into two groups, i.e., patients with periodontitis and those who were periodontally healthy. Saliva samples were collected and treated with 10% TCA/acetone/20 mM DTT to precipitate the proteins, which were then separated using two-dimensional polyacrylamide gel electrophoresis. Gel images were scanned using the GS-800TM Calibrated Densitometer. The protein spots were analyzed and expressed in percentage volumes. The percentage volume of each protein spot was subjected to Mann-Whitney statistical analysis using SPSS software and false discovery rate correction. When the expression of the salivary proteins was compared between the T2DM patients with periodontitis with those who were periodontally healthy, seven proteins, including polymeric immunoglobulin receptor, plastin-2, actin related protein 3, leukocyte elastase inhibitor, carbonic anhydrases 6, immunoglobulin J and interleukin-1 receptor antagonist, were found to be differentially expressed (p < 0.01304). This implies that the proteins may have the potential to be used as biomarkers for the prediction of T2DM patients who may be prone to periodontitis.
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Affiliation(s)
- Hang Haw Chan
- Department of Oral Biology, Faculty of Dentistry, University of Malaya, 50603 Kuala Lumpur, Malaysia; E-Mails: (H.H.C.); (K.J.)
| | - Zubaidah H. A. Rahim
- Department of Oral Biology, Faculty of Dentistry, University of Malaya, 50603 Kuala Lumpur, Malaysia; E-Mails: (H.H.C.); (K.J.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +603-79674851; Fax: +603-79674536
| | - Kala Jessie
- Department of Oral Biology, Faculty of Dentistry, University of Malaya, 50603 Kuala Lumpur, Malaysia; E-Mails: (H.H.C.); (K.J.)
| | - Onn H. Hashim
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia; E-Mail:
- University of Malaya Centre for Proteomics Research, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Tara B. Taiyeb-Ali
- Department of Oral Pathology and Oral Medicine and Periodontology, Faculty of Dentistry, University of Malaya, 50603 Kuala Lumpur, Malaysia; E-Mail:
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Plastin family of actin-bundling proteins: its functions in leukocytes, neurons, intestines, and cancer. Int J Cell Biol 2012; 2012:213492. [PMID: 22262972 PMCID: PMC3259490 DOI: 10.1155/2012/213492] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Revised: 09/29/2011] [Accepted: 10/04/2011] [Indexed: 11/25/2022] Open
Abstract
Sophisticated regulation of the actin cytoskeleton by a variety of actin-binding proteins is essential for eukaryotic cells to perform their diverse functions. The plastin (also know, as fimbrin) protein family belongs to actin-bundling proteins, and the protein family is evolutionarily conserved and expressed in yeast, plant, and animal cells. Plastins are characterized by EF-hand Ca2+-binding domains and actin-binding domains and can cross-link actin filaments into higher-order assemblies like bundles. Three isoforms have been identified in mammals. T-plastin is expressed in cells from solid tissues, such as neurons in the brain. I-plastin expression is restricted to intestine and kidney; the isoform plays a vital role in the function of absorptive epithelia in these organs. L-plastin is expressed in hematopoietic cell lineages and in many types of cancer cells; the isoform is thus considered to be a useful biomarker for cancer.
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47
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The actin-bundling protein L-plastin: a critical regulator of immune cell function. Int J Cell Biol 2011; 2012:935173. [PMID: 22194750 PMCID: PMC3238366 DOI: 10.1155/2012/935173] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Accepted: 10/12/2011] [Indexed: 01/08/2023] Open
Abstract
L-plastin is a leukocyte-specific protein that cross-links actin filaments into tight bundles, increasing the stability of actin-based structures such as podosomes and lamellipodia. While first identified as an abundant cytoplasmic protein in hematopoietically derived cells over 25 years ago, the requirement for L-plastin in multiple functions critical for immunity, such as antigen receptor signaling, adhesion, and motility, has only recently become clear. L-plastin has been identified as an important component in cellular processes critical for neutrophil, macrophage, osteoclast, eosinophil, and T- and B-lymphocyte biology. Following a brief description of the structure and function of L-plastin, the regulation of immune cell functions by L-plastin will be reviewed in detail.
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Ahn JH, Kim JH, Reuel NF, Barone PW, Boghossian AA, Zhang J, Yoon H, Chang AC, Hilmer AJ, Strano MS. Label-free, single protein detection on a near-infrared fluorescent single-walled carbon nanotube/protein microarray fabricated by cell-free synthesis. NANO LETTERS 2011; 11:2743-52. [PMID: 21627102 DOI: 10.1021/nl201033d] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Excessive sample volumes continue to be a major limitation in the analysis of protein-protein interactions, motivating the search for label-free detection methods of greater sensitivity. Herein, we report the first chemical approach for selective protein recognition using fluorescent single-walled carbon nanotubes (SWNTs) enabling label-free microarrays capable of single protein detection. Hexahistidine-tagged capture proteins directly expressed by cell-free synthesis on SWNT/chitosan microarray are bound to a Ni(2+) chelated by Nα,Nα-bis(carboxymethyl)-L-lysine grafted to chitosan surrounding the SWNT. The Ni(2+) acts as a proximity quencher with the Ni(2+)/SWNT distance altered upon docking of analyte proteins. This ability to discern single protein binding events decreases the apparent detection limit from 100 nM, for the ensemble average, to 10 pM for an observation time of 600 s. This first use of cell-free synthesis to functionalize a nanosensor extends this method to a virtually infinite number of capture proteins. To demonstrate this, the SWNT microarrays are used to analyze a network of 1156 protein-protein interactions in the staurosporine-induced apoptosis of SH-SY5Y cells, confirming literature predictions.
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Affiliation(s)
- Jin-Ho Ahn
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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Pazdrak K, Young TW, Straub C, Stafford S, Kurosky A. Priming of eosinophils by GM-CSF is mediated by protein kinase CbetaII-phosphorylated L-plastin. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2011; 186:6485-96. [PMID: 21525390 PMCID: PMC3100773 DOI: 10.4049/jimmunol.1001868] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The priming of eosinophils by cytokines leading to augmented response to chemoattractants and degranulating stimuli is a characteristic feature of eosinophils in the course of allergic inflammation and asthma. Actin reorganization and integrin activation are implicated in eosinophil priming by GM-CSF, but their molecular mechanism of action is unknown. In this regard, we investigated the role of L-plastin, an eosinophil phosphoprotein that we identified from eosinophil proteome analysis. Phosphoproteomic analysis demonstrated the upregulation of phosphorylated L-plastin after eosinophil stimulation with GM-CSF. Additionally, coimmunoprecipitation studies demonstrated a complex formation of phosphorylated L-plastin with protein kinase CβII (PKCβII), GM-CSF receptor α-chain, and two actin-associated proteins, paxilin and cofilin. Inhibition of PKCβII with 4,5-bis(4-fluoroanilino)phtalimide or PKCβII-specific small interfering RNA blocked GM-CSF-induced phosphorylation of L-plastin. Furthermore, flow cytometric analysis also showed an upregulation of α(M)β(2) integrin, which was sensitive to PKCβII inhibition. In chemotaxis assay, GM-CSF treatment allowed eosinophils to respond to lower concentrations of eotaxin, which was abrogated by the above-mentioned PKCβII inhibitors. Similarly, inhibition of PKCβII blocked GM-CSF induced priming for degranulation as assessed by release of eosinophil cationic protein and eosinophil peroxidase in response to eotaxin. Importantly, eosinophil stimulation with a synthetic L-plastin peptide (residues 2-19) phosphorylated on Ser(5) upregulated α(M)β(2) integrin expression and increased eosinophil migration in response to eotaxin independent of GM-CSF stimulation. Our results establish a causative role for PKCβII and L-plastin in linking GM-CSF-induced eosinophil priming for chemotaxis and degranulation to signaling events associated with integrin activation via induction of PKCβII-mediated L-plastin phosphorylation.
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Affiliation(s)
- Konrad Pazdrak
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555
- UTMB National Heart, Lung, and Blood Institute Proteomics Center, University of Texas Medical Branch, Galveston, TX 77555
| | - Travis W. Young
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555
- UTMB National Heart, Lung, and Blood Institute Proteomics Center, University of Texas Medical Branch, Galveston, TX 77555
| | - Christof Straub
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555
- UTMB National Heart, Lung, and Blood Institute Proteomics Center, University of Texas Medical Branch, Galveston, TX 77555
| | - Susan Stafford
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555
- UTMB National Heart, Lung, and Blood Institute Proteomics Center, University of Texas Medical Branch, Galveston, TX 77555
| | - Alexander Kurosky
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555
- UTMB National Heart, Lung, and Blood Institute Proteomics Center, University of Texas Medical Branch, Galveston, TX 77555
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Verma NK, Dempsey E, Freeley M, Botting CH, Long A, Kelleher D, Volkov Y. Analysis of dynamic tyrosine phosphoproteome in LFA-1 triggered migrating T-cells. J Cell Physiol 2011; 226:1489-98. [PMID: 20945386 DOI: 10.1002/jcp.22478] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The ordered, directional migration of T-lymphocytes is a key process during immune surveillance and response. This requires cell adhesion to the high endothelial venules or to the extracellular matrix by a series of surface receptor/ligand interactions involving adhesion molecules of the integrin family including lymphocyte function associated molecule-1 (LFA-1) and intercellular adhesion molecules (ICAMs). Reversible protein phosphorylation is emerging as a key player in the regulation of biological functions with tyrosine phosphorylation playing a crucial role in signal transduction. Thus, the study of this type of post-translational modification at the proteomic level has great biological significance. In this work, phospho-enriched cell lysates from LFA-1-triggered migrating human T-cells were subjected to immunoaffinity purification of tyrosine phosphorylated proteins, mass spectrometric, and bioinformatic analysis. In addition to the identification of several well-documented proteins, the analysis suggested involvement of a number of new and novel proteins in LFA-1 induced T-cell migration. This dataset expands the list of the signaling components of the LFA-1 induced phosphotyrosine protein complexes in migrating T-cells that will be extremely useful in the study of their specific roles within LFA-1 associated signaling pathways. Identification of proteins previously not reported in the context of LFA-1 stimulated signal transduction might provide new insights into understanding the LFA-1 signaling networks and aid in the search for new potential therapeutic targets.
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Affiliation(s)
- Navin K Verma
- Department of Clinical Medicine, Institute of Molecular Medicine, Trinity College Dublin, Ireland.
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