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Yuan Y, Li P, Li J, Zhao Q, Chang Y, He X. Protein lipidation in health and disease: molecular basis, physiological function and pathological implication. Signal Transduct Target Ther 2024; 9:60. [PMID: 38485938 PMCID: PMC10940682 DOI: 10.1038/s41392-024-01759-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 12/31/2023] [Accepted: 01/24/2024] [Indexed: 03/18/2024] Open
Abstract
Posttranslational modifications increase the complexity and functional diversity of proteins in response to complex external stimuli and internal changes. Among these, protein lipidations which refer to lipid attachment to proteins are prominent, which primarily encompassing five types including S-palmitoylation, N-myristoylation, S-prenylation, glycosylphosphatidylinositol (GPI) anchor and cholesterylation. Lipid attachment to proteins plays an essential role in the regulation of protein trafficking, localisation, stability, conformation, interactions and signal transduction by enhancing hydrophobicity. Accumulating evidence from genetic, structural, and biomedical studies has consistently shown that protein lipidation is pivotal in the regulation of broad physiological functions and is inextricably linked to a variety of diseases. Decades of dedicated research have driven the development of a wide range of drugs targeting protein lipidation, and several agents have been developed and tested in preclinical and clinical studies, some of which, such as asciminib and lonafarnib are FDA-approved for therapeutic use, indicating that targeting protein lipidations represents a promising therapeutic strategy. Here, we comprehensively review the known regulatory enzymes and catalytic mechanisms of various protein lipidation types, outline the impact of protein lipidations on physiology and disease, and highlight potential therapeutic targets and clinical research progress, aiming to provide a comprehensive reference for future protein lipidation research.
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Affiliation(s)
- Yuan Yuan
- Department of Gastroenterology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Peiyuan Li
- Department of Gastroenterology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jianghui Li
- Department of Gastroenterology, Zhongnan Hospital of Wuhan University, Wuhan, China
- Hubei Clinical Center and Key Laboratory of Intestinal and Colorectal Diseases, Wuhan, China
| | - Qiu Zhao
- Department of Gastroenterology, Zhongnan Hospital of Wuhan University, Wuhan, China.
- Hubei Clinical Center and Key Laboratory of Intestinal and Colorectal Diseases, Wuhan, China.
| | - Ying Chang
- Department of Gastroenterology, Zhongnan Hospital of Wuhan University, Wuhan, China.
- Hubei Clinical Center and Key Laboratory of Intestinal and Colorectal Diseases, Wuhan, China.
| | - Xingxing He
- Department of Gastroenterology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
- Department of Gastroenterology, Zhongnan Hospital of Wuhan University, Wuhan, China.
- Hubei Clinical Center and Key Laboratory of Intestinal and Colorectal Diseases, Wuhan, China.
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2
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Whitley JA, Kim S, Lou L, Ye C, Alsaidan OA, Sulejmani E, Cai J, Desrochers EG, Beharry Z, Rickman CB, Klingeborn M, Liu Y, Xie Z, Cai H. Encapsulating Cas9 into extracellular vesicles by protein myristoylation. J Extracell Vesicles 2022; 11:e12196. [PMID: 35384352 PMCID: PMC8982324 DOI: 10.1002/jev2.12196] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 01/20/2022] [Accepted: 02/02/2022] [Indexed: 01/29/2023] Open
Abstract
CRISPR/Cas9 genome editing is a very promising avenue for the treatment of a variety of genetic diseases. However, it is still very challenging to encapsulate CRISPR/Cas9 machinery for delivery. Protein N-myristoylation is an irreversible co/post-translational modification that results in the covalent attachment of the myristoyl-group to the N-terminus of a target protein. It serves as an anchor for a protein to associate with the cell membrane and determines its intracellular trafficking and activity. Extracellular vesicles (EVs) are secreted vesicles that mediate cell-cell communication. In this study, we demonstrate that myristoylated proteins were preferentially encapsulated into EVs. The octapeptide derived from the leading sequence of the N-terminus of Src kinase was a favourable substrate for N-myristoyltransferase 1, the enzyme that catalyzes myristoylation. The fusion of the octapeptide onto the N-terminus of Cas9 promoted the myristoylation and encapsulation of Cas9 into EVs. Encapsulation of Cas9 and sgRNA-eGFP inside EVs was confirmed using protease digestion assays. Additionally, to increase the transfection potential, VSV-G was introduced into the EVs. The encapsulated Cas9 in EVs accounted for 0.7% of total EV protein. Importantly, the EVs coated with VSV-G encapsulating Cas9/sgRNA-eGFP showed up to 42% eGFP knock out efficiency with limited off-target effects in recipient cells. Our study provides a novel approach to encapsulate CRISPR/Cas9 protein and sgRNA into EVs. This strategy may open an effective avenue to utilize EVs as vehicles to deliver CRISPR/Cas9 for genome-editing-based gene therapy.
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Affiliation(s)
- Joseph Andrew Whitley
- Department of Pharmaceutical and Biomedical SciencesCollege of PharmacyUniversity of GeorgiaAthensGeorgiaUSA
| | - Sungjin Kim
- Department of Pharmaceutical and Biomedical SciencesCollege of PharmacyUniversity of GeorgiaAthensGeorgiaUSA
| | - Lei Lou
- School of Electrical and Computer EngineeringCollege of EngineeringUniversity of GeorgiaAthensGeorgiaUSA
| | - Chenming Ye
- Department of Pharmaceutical and Biomedical SciencesCollege of PharmacyUniversity of GeorgiaAthensGeorgiaUSA
| | - Omar Awad Alsaidan
- Department of Pharmaceutical and Biomedical SciencesCollege of PharmacyUniversity of GeorgiaAthensGeorgiaUSA
| | - Essilvo Sulejmani
- Department of Pharmaceutical and Biomedical SciencesCollege of PharmacyUniversity of GeorgiaAthensGeorgiaUSA
| | - Jingwen Cai
- Department of Cellular Biology and AnatomyAugusta UniversityAugustaGeorgiaUSA
| | - Ellison Gerona Desrochers
- School of Electrical and Computer EngineeringCollege of EngineeringUniversity of GeorgiaAthensGeorgiaUSA
| | - Zanna Beharry
- Department of Chemical and Physical SciencesUniversity of Virgin IslandsSt. ThomasVirgin Islands
| | - Catherine Bowes Rickman
- Department of OphthalmologyDuke UniversityDurhamNorth CarolinaUSA
- Department of Cell BiologyDuke UniversityDurhamNorth CarolinaUSA
| | | | - Yutao Liu
- Department of Cellular Biology and AnatomyAugusta UniversityAugustaGeorgiaUSA
| | - Zhong‐Ru Xie
- School of Electrical and Computer EngineeringCollege of EngineeringUniversity of GeorgiaAthensGeorgiaUSA
| | - Houjian Cai
- Department of Pharmaceutical and Biomedical SciencesCollege of PharmacyUniversity of GeorgiaAthensGeorgiaUSA
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Li W, Li F, Zhang X, Lin HK, Xu C. Insights into the post-translational modification and its emerging role in shaping the tumor microenvironment. Signal Transduct Target Ther 2021; 6:422. [PMID: 34924561 PMCID: PMC8685280 DOI: 10.1038/s41392-021-00825-8] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 11/02/2021] [Accepted: 11/05/2021] [Indexed: 12/11/2022] Open
Abstract
More and more in-depth studies have revealed that the occurrence and development of tumors depend on gene mutation and tumor heterogeneity. The most important manifestation of tumor heterogeneity is the dynamic change of tumor microenvironment (TME) heterogeneity. This depends not only on the tumor cells themselves in the microenvironment where the infiltrating immune cells and matrix together forming an antitumor and/or pro-tumor network. TME has resulted in novel therapeutic interventions as a place beyond tumor beds. The malignant cancer cells, tumor infiltrate immune cells, angiogenic vascular cells, lymphatic endothelial cells, cancer-associated fibroblastic cells, and the released factors including intracellular metabolites, hormonal signals and inflammatory mediators all contribute actively to cancer progression. Protein post-translational modification (PTM) is often regarded as a degradative mechanism in protein destruction or turnover to maintain physiological homeostasis. Advances in quantitative transcriptomics, proteomics, and nuclease-based gene editing are now paving the global ways for exploring PTMs. In this review, we focus on recent developments in the PTM area and speculate on their importance as a critical functional readout for the regulation of TME. A wealth of information has been emerging to prove useful in the search for conventional therapies and the development of global therapeutic strategies.
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Affiliation(s)
- Wen Li
- grid.54549.390000 0004 0369 4060Integrative Cancer Center & Cancer Clinical Research Center, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, 610042 Chengdu, P. R. China
| | - Feifei Li
- grid.54549.390000 0004 0369 4060Integrative Cancer Center & Cancer Clinical Research Center, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, 610042 Chengdu, P. R. China ,grid.256607.00000 0004 1798 2653Guangxi Collaborative Innovation Center for Biomedicine (Guangxi-ASEAN Collaborative Innovation Center for Major Disease Prevention and Treatment), Guangxi Medical University, 530021 Nanning, Guangxi China
| | - Xia Zhang
- grid.410570.70000 0004 1760 6682Institute of Pathology and Southwest Cancer Center, Southwest Hospital, Third Military Medical University (Army Medical University), 400038 Chongqing, China
| | - Hui-Kuan Lin
- grid.241167.70000 0001 2185 3318Department of Cancer Biology, Wake Forest Baptist Medical Center, Wake Forest University, Winston Salem, NC 27101 USA
| | - Chuan Xu
- Integrative Cancer Center & Cancer Clinical Research Center, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, 610042, Chengdu, P. R. China. .,Department of Cancer Biology, Wake Forest Baptist Medical Center, Wake Forest University, Winston Salem, NC, 27101, USA.
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4
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Protein N-myristoylation: functions and mechanisms in control of innate immunity. Cell Mol Immunol 2021; 18:878-888. [PMID: 33731917 PMCID: PMC7966921 DOI: 10.1038/s41423-021-00663-2] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 02/18/2021] [Indexed: 02/08/2023] Open
Abstract
Protein N-myristoylation is an important fatty acylation catalyzed by N-myristoyltransferases (NMTs), which are ubiquitous enzymes in eukaryotes. Specifically, attachment of a myristoyl group is vital for proteins participating in various biological functions, including signal transduction, cellular localization, and oncogenesis. Recent studies have revealed unexpected mechanisms indicating that protein N-myristoylation is involved in host defense against microbial and viral infections. In this review, we describe the current understanding of protein N-myristoylation (mainly focusing on myristoyl switches) and summarize its crucial roles in regulating innate immune responses, including TLR4-dependent inflammatory responses and demyristoylation-induced innate immunosuppression during Shigella flexneri infection. Furthermore, we examine the role of myristoylation in viral assembly, intracellular host interactions, and viral spread during human immunodeficiency virus-1 (HIV-1) infection. Deeper insight into the relationship between protein N-myristoylation and innate immunity might enable us to clarify the pathogenesis of certain infectious diseases and better harness protein N-myristoylation for new therapeutics.
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Kosciuk T, Lin H. N-Myristoyltransferase as a Glycine and Lysine Myristoyltransferase in Cancer, Immunity, and Infections. ACS Chem Biol 2020; 15:1747-1758. [PMID: 32453941 DOI: 10.1021/acschembio.0c00314] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Protein myristoylation, the addition of a 14-carbon saturated acyl group, is an abundant modification implicated in biological events as diverse as development, immunity, oncogenesis, and infections. N-Myristoyltransferase (NMT) is the enzyme that catalyzes this modification. Many elegant studies have established the rules guiding the catalysis including substrate amino acid sequence requirements with the indispensable N-terminal glycine, and a co-translational mode of action. Recent advances in technology such as the development of fatty acid analogs, small molecule inhibitors, and new proteomic strategies, allowed a deeper insight into the NMT activity and function. Here we focus on discussing recent work demonstrating that NMT is also a lysine myristoyltransferase, the enzyme's regulation by a previously unnoticed solvent channel, and the mechanism of NMT regulation by protein-protein interactions. We also summarize recent findings on NMT's role in cancer, immunity, and infections and the advances in pharmacological targeting of myristoylation. Our analyses highlight opportunities for further understanding and discoveries.
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Affiliation(s)
- Tatsiana Kosciuk
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853, United States
| | - Hening Lin
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
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Wen Z, Jin K, Shen Y, Yang Z, Li Y, Wu B, Tian L, Shoor S, Roche NE, Goronzy JJ, Weyand CM. N-myristoyltransferase deficiency impairs activation of kinase AMPK and promotes synovial tissue inflammation. Nat Immunol 2019; 20:313-325. [PMID: 30718913 PMCID: PMC6396296 DOI: 10.1038/s41590-018-0296-7] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 12/06/2018] [Indexed: 01/24/2023]
Abstract
N-myristoyltransferase (NMT) attaches the fatty acid myristate to the N-terminal glycine of proteins to sort them into soluble and membrane-bound fractions. Function of the energy-sensing AMP-activated protein kinase, AMPK, is myristoylation dependent. In rheumatoid arthritis (RA), pathogenic T cells shift glucose away from adenosine tri-phosphate production toward synthetic and proliferative programs, promoting proliferation, cytokine production, and tissue invasion. We found that RA T cells had a defect in NMT1 function, which prevented AMPK activation and enabled unopposed mTORC1 signaling. Lack of the myristate lipid tail disrupted the lysosomal translocation and activation of AMPK. Instead, myristoylation-incompetent RA T cells hyperactivated the mTORC1 pathway and differentiated into pro-inflammatory TH1 and TH17 helper T cells. In vivo, NMT1 loss caused robust synovial tissue inflammation, whereas forced NMT1 overexpression rescued AMPK activation and suppressed synovitis. Thus, NMT1 has tissue-protective functions by facilitating lysosomal recruitment of AMPK and dampening mTORC1 signaling.
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Affiliation(s)
- Zhenke Wen
- Division of Immunology and Rheumatology, Stanford University School of Medicine, Stanford, CA, USA
| | - Ke Jin
- Division of Immunology and Rheumatology, Stanford University School of Medicine, Stanford, CA, USA
| | - Yi Shen
- Division of Immunology and Rheumatology, Stanford University School of Medicine, Stanford, CA, USA
| | - Zhen Yang
- Division of Immunology and Rheumatology, Stanford University School of Medicine, Stanford, CA, USA
| | - Yinyin Li
- Division of Immunology and Rheumatology, Stanford University School of Medicine, Stanford, CA, USA
| | - Bowen Wu
- Division of Immunology and Rheumatology, Stanford University School of Medicine, Stanford, CA, USA
| | - Lu Tian
- Department of Biomedical Data Science, Stanford University School of Medicine, Stanford, CA, USA
| | - Stanford Shoor
- Division of Immunology and Rheumatology, Stanford University School of Medicine, Stanford, CA, USA
| | - Niall E Roche
- Arthritis Center, Stanford Health Care-ValleyCare, Pleasanton, CA, USA
| | - Jorg J Goronzy
- Division of Immunology and Rheumatology, Stanford University School of Medicine, Stanford, CA, USA
| | - Cornelia M Weyand
- Division of Immunology and Rheumatology, Stanford University School of Medicine, Stanford, CA, USA.
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Human in vivo-generated monocyte-derived dendritic cells and macrophages cross-present antigens through a vacuolar pathway. Nat Commun 2018; 9:2570. [PMID: 29967419 PMCID: PMC6028641 DOI: 10.1038/s41467-018-04985-0] [Citation(s) in RCA: 134] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2017] [Accepted: 06/08/2018] [Indexed: 12/20/2022] Open
Abstract
Presentation of exogenous antigens on MHC-I molecules, termed cross-presentation, is essential for cytotoxic CD8+ T cell responses. In mice, dendritic cells (DCs) that arise from monocytes (mo-DCs) during inflammation have a key function in these responses by cross-presenting antigens locally in peripheral tissues. Whether human naturally-occurring mo-DCs can cross-present is unknown. Here, we use human mo-DCs and macrophages directly purified from ascites to address this question. Single-cell RNA-seq data show that ascites CD1c+ DCs contain exclusively monocyte-derived cells. Both ascites mo-DCs and monocyte-derived macrophages cross-present efficiently, but are inefficient for transferring exogenous proteins into their cytosol. Inhibition of cysteine proteases, but not of proteasome, abolishes cross-presentation in these cells. We conclude that human monocyte-derived cells cross-present exclusively using a vacuolar pathway. Finally, only ascites mo-DCs provide co-stimulatory signals to induce effector cytotoxic CD8+ T cells. Our findings thus provide important insights on how to harness cross-presentation for therapeutic purposes.
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Schlott AC, Holder AA, Tate EW. N-Myristoylation as a Drug Target in Malaria: Exploring the Role of N-Myristoyltransferase Substrates in the Inhibitor Mode of Action. ACS Infect Dis 2018; 4:449-457. [PMID: 29363940 DOI: 10.1021/acsinfecdis.7b00203] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Malaria continues to be a significant cause of death and morbidity worldwide, and there is a need for new antimalarial drugs with novel targets. We have focused as a potential target for drug development on N-myristoyl transferase (NMT), an enzyme that acylates a wide range of substrate proteins. The NMT substrates in Plasmodium falciparum include some proteins that are common to processes in eukaryotes such as secretory transport and others that are unique to apicomplexan parasites. Myristoylation facilitates a protein interaction with membranes that may be strengthened by further lipidation, and the inhibition of NMT results in incorrect protein localization and the consequent disruption of function. The diverse roles of NMT substrates mean that NMT inhibition has a pleiotropic and severe impact on parasite development, growth, and multiplication. To study the mode of action underlying NMT inhibition, it is important to consider the function of proteins upstream and downstream of NMT. In this work, we therefore present our current perspective on the different functions of known NMT substrates as well as compare the inhibition of cotranslational myristoylation to the inhibition of known targets upstream of NMT.
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Affiliation(s)
- Anja C. Schlott
- Malaria Parasitology, The Francis Crick Institute, 1 Midland Road, NW1 1AT London, United Kingdom
- Department of Chemistry, Imperial College London, Imperial College Road, SW7 2AZ London, United Kingdom
| | - Anthony A. Holder
- Malaria Parasitology, The Francis Crick Institute, 1 Midland Road, NW1 1AT London, United Kingdom
| | - Edward W. Tate
- Department of Chemistry, Imperial College London, Imperial College Road, SW7 2AZ London, United Kingdom
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In silico identification of microRNAs predicted to regulate N-myristoyltransferase and Methionine Aminopeptidase 2 functions in cancer and infectious diseases. PLoS One 2018; 13:e0194612. [PMID: 29579063 PMCID: PMC5868815 DOI: 10.1371/journal.pone.0194612] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2017] [Accepted: 03/06/2018] [Indexed: 01/16/2023] Open
Abstract
Protein myristoylation is a key protein modification carried out by N-Myristoyltransferase (NMT) after Methionine aminopeptidase 2 (MetAP2) removes methionine from the amino-terminus of the target protein. Protein myristoylation by NMT augments several signaling pathways involved in a myriad of cellular processes, including developmental pathways and pathways that when dysregulated lead to cancer or immune dysfunction. The emerging evidence pointing to NMT-mediated myristoylation as a major cellular regulator underscores the importance of understanding the framework of this type of signaling event. Various studies have investigated the role that myristoylation plays in signaling dysfunction by examining differential gene or protein expression between normal and diseased states, such as cancers or following HIV-1 infection, however no study exists that addresses the role of microRNAs (miRNAs) in the regulation of myristoylation. By performing a large scale bioinformatics and functional analysis of the miRNAs that target key genes involved in myristoylation (NMT1, NMT2, MetAP2), we have narrowed down a list of promising candidates for further analysis. Our condensed panel of miRNAs identifies 35 miRNAs linked to cancer, 21 miRNAs linked to developmental and immune signaling pathways, and 14 miRNAs linked to infectious disease (primarily HIV). The miRNAs panel that was analyzed revealed several NMT-targeting mRNAs (messenger RNA) that are implicated in diseases associated with NMT signaling alteration, providing a link between the realms of miRNA and myristoylation signaling. These findings verify miRNA as an additional facet of myristoylation signaling that must be considered to gain a full perspective. This study provides the groundwork for future studies concerning NMT-transcript-binding miRNAs, and will potentially lead to the development of new diagnostic/prognostic biomarkers and therapeutic targets for several important diseases.
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Jiang H, Zhang X, Chen X, Aramsangtienchai P, Tong Z, Lin H. Protein Lipidation: Occurrence, Mechanisms, Biological Functions, and Enabling Technologies. Chem Rev 2018; 118:919-988. [PMID: 29292991 DOI: 10.1021/acs.chemrev.6b00750] [Citation(s) in RCA: 275] [Impact Index Per Article: 45.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Protein lipidation, including cysteine prenylation, N-terminal glycine myristoylation, cysteine palmitoylation, and serine and lysine fatty acylation, occurs in many proteins in eukaryotic cells and regulates numerous biological pathways, such as membrane trafficking, protein secretion, signal transduction, and apoptosis. We provide a comprehensive review of protein lipidation, including descriptions of proteins known to be modified and the functions of the modifications, the enzymes that control them, and the tools and technologies developed to study them. We also highlight key questions about protein lipidation that remain to be answered, the challenges associated with answering such questions, and possible solutions to overcome these challenges.
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Affiliation(s)
- Hong Jiang
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Xiaoyu Zhang
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Xiao Chen
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Pornpun Aramsangtienchai
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Zhen Tong
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Hening Lin
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
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Kim S, Yang X, Li Q, Wu M, Costyn L, Beharry Z, Bartlett MG, Cai H. Myristoylation of Src kinase mediates Src-induced and high-fat diet-accelerated prostate tumor progression in mice. J Biol Chem 2017; 292:18422-18433. [PMID: 28939770 DOI: 10.1074/jbc.m117.798827] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 09/21/2017] [Indexed: 12/11/2022] Open
Abstract
Exogenous fatty acids provide substrates for energy production and biogenesis of the cytoplasmic membrane, but they also enhance cellular signaling during cancer cell proliferation. However, it remains controversial whether dietary fatty acids are correlated with tumor progression. In this study, we demonstrate that increased Src kinase activity is associated with high-fat diet-accelerated progression of prostate tumors and that Src kinases mediate this pathological process. Moreover, in the in vivo prostate regeneration assay, host SCID mice carrying Src(Y529F)-transduced regeneration tissues were fed a low-fat diet or a high-fat diet and treated with vehicle or dasatinib. The high-fat diet not only accelerated Src-induced prostate tumorigenesis in mice but also compromised the inhibitory effect of the anticancer drug dasatinib on Src kinase oncogenic potential in vivo We further show that myristoylation of Src kinase is essential to facilitate Src-induced and high-fat diet-accelerated tumor progression. Mechanistically, metabolism of exogenous myristic acid increased the biosynthesis of myristoyl CoA and myristoylated Src and promoted Src kinase-mediated oncogenic signaling in human cells. Of the fatty acids tested, only exogenous myristic acid contributed to increased intracellular myristoyl CoA levels. Our results suggest that targeting Src kinase myristoylation, which is required for Src kinase association at the cellular membrane, blocks dietary fat-accelerated tumorigenesis in vivo Our findings uncover the molecular basis of how the metabolism of myristic acid stimulates high-fat diet-mediated prostate tumor progression.
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Affiliation(s)
- Sungjin Kim
- From the Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, Georgia 30602 and
| | - Xiangkun Yang
- From the Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, Georgia 30602 and
| | - Qianjin Li
- From the Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, Georgia 30602 and
| | - Meng Wu
- From the Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, Georgia 30602 and
| | - Leah Costyn
- From the Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, Georgia 30602 and
| | - Zanna Beharry
- the Department of Chemistry and Physics, Florida Gulf Coast University, Fort Myers, Florida 33965
| | - Michael G Bartlett
- From the Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, Georgia 30602 and
| | - Houjian Cai
- From the Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, Georgia 30602 and
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12
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Udenwobele DI, Su RC, Good SV, Ball TB, Varma Shrivastav S, Shrivastav A. Myristoylation: An Important Protein Modification in the Immune Response. Front Immunol 2017; 8:751. [PMID: 28713376 PMCID: PMC5492501 DOI: 10.3389/fimmu.2017.00751] [Citation(s) in RCA: 112] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 06/13/2017] [Indexed: 01/24/2023] Open
Abstract
Protein N-myristoylation is a cotranslational lipidic modification specific to the alpha-amino group of an N-terminal glycine residue of many eukaryotic and viral proteins. The ubiquitous eukaryotic enzyme, N-myristoyltransferase, catalyzes the myristoylation process. Precisely, attachment of a myristoyl group increases specific protein–protein interactions leading to subcellular localization of myristoylated proteins with its signaling partners. The birth of the field of myristoylation, a little over three decades ago, has led to the understanding of the significance of protein myristoylation in regulating cellular signaling pathways in several biological processes especially in carcinogenesis and more recently immune function. This review discusses myristoylation as a prerequisite step in initiating many immune cell signaling cascades. In particular, we discuss the hitherto unappreciated implication of myristoylation during myelopoiesis, innate immune response, lymphopoiesis for T cells, and the formation of the immunological synapse. Furthermore, we discuss the role of myristoylation in inducing the virological synapse during human immunodeficiency virus infection as well as its clinical implication. This review aims to summarize existing knowledge in the field and to highlight gaps in our understanding of the role of myristoylation in immune function so as to further investigate into the dynamics of myristoylation-dependent immune regulation.
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Affiliation(s)
- Daniel Ikenna Udenwobele
- Department of Biology, University of Winnipeg, Winnipeg, MB, Canada.,Department of Biochemistry, University of Nigeria, Nsukka, Enugu, Nigeria
| | - Ruey-Chyi Su
- JC Wilt Infectious Diseases Research Institute, National HIV and Retrovirology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada
| | - Sara V Good
- Department of Biology, University of Winnipeg, Winnipeg, MB, Canada
| | - Terry Blake Ball
- JC Wilt Infectious Diseases Research Institute, National HIV and Retrovirology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada.,Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, MB, Canada
| | - Shailly Varma Shrivastav
- Department of Biology, University of Winnipeg, Winnipeg, MB, Canada.,VastCon Inc., Winnipeg, MB, Canada
| | - Anuraag Shrivastav
- Department of Biology, University of Winnipeg, Winnipeg, MB, Canada.,Department of Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, MB, Canada
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Rampoldi F, Bonrouhi M, Boehm ME, Lehmann WD, Popovic ZV, Kaden S, Federico G, Brunk F, Gröne HJ, Porubsky S. Immunosuppression and Aberrant T Cell Development in the Absence of N-Myristoylation. THE JOURNAL OF IMMUNOLOGY 2015; 195:4228-43. [DOI: 10.4049/jimmunol.1500622] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 09/01/2015] [Indexed: 01/01/2023]
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14
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Kumar S, Sharma RK. N-terminal region of the catalytic domain of human N-myristoyltransferase 1 acts as an inhibitory module. PLoS One 2015; 10:e0127661. [PMID: 26000639 PMCID: PMC4441422 DOI: 10.1371/journal.pone.0127661] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 04/17/2015] [Indexed: 11/18/2022] Open
Abstract
N-myristoyltransferase (NMT) plays critical roles in the modulation of various signaling molecules, however, the regulation of this enzyme in diverse cellular states remains poorly understood. We provide experimental evidence to show for the first time that for the isoform 1 of human NMT (hNMT1), the regulatory roles extend into the catalytic core. In our present study, we expressed, purified, and characterized a truncation mutant devoid of 28 N-terminal amino acids from the catalytic module (Δ28-hNMT1s) and compared its properties to the full-length catalytic domain of hNMT1. The deletion of the N-terminal peptide had no effect on the enzyme stability. Our findings suggest that the N-terminal region in the catalytic module of hNMT1 functions serves as a regulatory control element. The observations of an ~3 fold increase in enzymatic efficiency following removal of the N-terminal peptide of hNMT1s indicates that N-terminal amino acids acts as an inhibitory segment and negatively regulate the enzyme activity. Our findings that the N-terminal region confers control over activity, taken together with the earlier observations that the N-terminal of hNMT1 is differentially processed in diverse cellular states, suggests that the proteolytic processing of the peptide segment containing the inhibitory region provides a molecular mechanism for physiological up-regulation of myristoyltransferase activity.
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Affiliation(s)
- Sujeet Kumar
- Department of Pathology and Laboratory Medicine, Cancer Cluster, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Rajendra K. Sharma
- Department of Pathology and Laboratory Medicine, Cancer Cluster, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
- * E-mail: (RKS)
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15
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Kumar A, Jaggi AS, Singh N. Pharmacology of Src family kinases and therapeutic implications of their modulators. Fundam Clin Pharmacol 2015; 29:115-30. [PMID: 25545125 DOI: 10.1111/fcp.12097] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 11/18/2014] [Accepted: 12/02/2014] [Indexed: 12/23/2022]
Abstract
Src family kinases (SFKs), the largest family of nonreceptor tyrosine kinases, include 10 members. Src was the first gene product discovered to have intrinsic protein tyrosine kinase activity. Src is widely expressed in many cell types and can have different locations within a cell; the subcellular location of Src can affect its function. Src can associate with cellular membranes, such as the plasma membrane, the perinuclear membrane, and the endosomal membrane. SFKs actions on mammalian cells are pleiotropic and include effect on cell morphology, adhesion, migration, invasion, proliferation, differentiation, and survival. SFKs at one end have been documented to play some important physiological functions; on the other end, they have been described in the pathophysiology of some disorders. In this review article, an exhaustive attempt has been made to unearth pharmacology of SFKs and therapeutic implications of SFKs modulators.
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Affiliation(s)
- Amit Kumar
- CNS and CVS Research Laboratory, Pharmacology Division, Department of Pharmaceutical Sciences and Drug Research, Faculty of Medicine, Punjabi University, Patiala, 147002, Punjab, India
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16
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Periostin secreted by glioblastoma stem cells recruits M2 tumour-associated macrophages and promotes malignant growth. Nat Cell Biol 2015; 17:170-82. [PMID: 25580734 PMCID: PMC4312504 DOI: 10.1038/ncb3090] [Citation(s) in RCA: 631] [Impact Index Per Article: 70.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 11/26/2014] [Indexed: 02/06/2023]
Abstract
Tumor-associated macrophages (TAMs) are enriched in glioblastoma (GBM) that contains glioma stem cells (GSCs) at the apex of its cellular hierarchy. The correlation between TAM density and glioma grade suggests a supportive role of TAMs in tumor progression. Here we interrogated the molecular link between GSCs and TAM recruitment in GBMs and demonstrated that GSCs secrete Periostin (POSTN) to recruit TAMs. TAM density correlates with POSTN levels in human GBMs. Silencing POSTN in GSCs markedly reduced TAM density, inhibited tumor growth, and increased survival of mice bearing GSC-derived xenografts. We found that TAMs in GBMs are not brain-resident microglia, but mainly monocyte-derived macrophages from peripheral blood. Disrupting POSTN specifically attenuated the tumor supportive M2 type of TAMs in xenografts. POSTN recruits TAMs through integrin αvβ3 as blocking this signaling by an RGD peptide inhibited TAM recruitment. Our findings highlight the possibility of improving GBM treatment by targeting POSTN-mediated TAM recruitment.
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17
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Bhat S, Mary S, Banarjee R, Giri AP, Kulkarni MJ. Immune response to chemically modified proteome. Proteomics Clin Appl 2014; 8:19-34. [PMID: 24375944 DOI: 10.1002/prca.201300068] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 12/06/2013] [Accepted: 12/09/2013] [Indexed: 11/10/2022]
Abstract
Both enzymatic and nonenzymatic PTMs of proteins involve chemical modifications. Some of these modifications are prerequisite for the normal functioning of cell, while other chemical modifications render the proteins as "neo-self" antigens, which are recognized as "non-self" leading to aberrant cellular and humoral immune responses. However, these modifications could be a secondary effect of autoimmune diseases, as in the case of type I diabetes, hyperglycemia leads to protein glycation. The enigma of chemical modifications and immune response is akin to the "chick-and-egg" paradox. Nevertheless, chemical modifications regulate immune response. In some of the well-known autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, and multiple sclerosis, chemically modified proteins act as autoantigens forming immune complexes. In some instances, chemical modifications are also involved in regulating immune response during pathogen infection. Further, the usefulness of proteomic analysis of immune complexes is briefly discussed.
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Affiliation(s)
- Shweta Bhat
- Proteomics Facility, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune, India
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18
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Recent Advances in The Discovery ofN-Myristoyltransferase Inhibitors. ChemMedChem 2014; 9:2425-37. [DOI: 10.1002/cmdc.201402174] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Revised: 07/17/2014] [Indexed: 01/08/2023]
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19
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Comprehensive review on the HSC70 functions, interactions with related molecules and involvement in clinical diseases and therapeutic potential. Pharmacol Ther 2012; 136:354-74. [PMID: 22960394 DOI: 10.1016/j.pharmthera.2012.08.014] [Citation(s) in RCA: 193] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Accepted: 08/14/2012] [Indexed: 12/28/2022]
Abstract
Heat shock cognate protein 70 (HSC70) is a constitutively expressed molecular chaperone which belongs to the heat shock protein 70 (HSP70) family. HSC70 shares some of the structural and functional similarity with HSP70. HSC70 also has different properties compared with HSP70 and other heat shock family members. HSC70 performs its full functions by the cooperation of co-chaperones. It interacts with many other molecules as well and regulates various cellular functions. It is also involved in various diseases and may become a biomarker for diagnosis and potential therapeutic targets for design, discovery, and development of novel drugs to treat various diseases. In this article, we provide a comprehensive review on HSC70 from the literatures including the basic general information such as classification, structure and cellular location, genetics and function, as well as its protein association and interaction with other proteins. In addition, we also discussed the relationship of HSC70 and related clinical diseases such as cancer, cardiovascular, neurological, hepatic and many other diseases and possible therapeutic potential and highlight the progress and prospects of research in this field. Understanding the functions of HSC70 and its interaction with other molecules will help us to reveal other novel properties of this protein. Scientists may be able to utilize this protein as a biomarker and therapeutic target to make significant advancement in scientific research and clinical setting in the future.
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20
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N-myristoyltransferase in the leukocytic development processes. Cell Tissue Res 2011; 345:203-11. [PMID: 21698528 DOI: 10.1007/s00441-011-1202-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Accepted: 06/03/2011] [Indexed: 02/07/2023]
Abstract
The lipidic modification of proteins has recently been shown to be of immense importance, although many of the roles of these modifications remain as yet unidentified. One of such key modifications occurring on several proteins is the covalent addition of a 14-carbon long saturated fatty acid, a process termed myristoylation. Myristoylation can occur during both co-translational protein synthesis and posttranslationally, confers lipophilicity to protein molecules, and controls protein functions. The protein myristoylation process is catalyzed by the enzyme N-myristoyltransferase (NMT), which exists as two isoforms: NMT1 and NMT2. NMT1 is essential for growth and development, during which rapid cellular proliferation is required, in a variety of organisms. NMT1 is also reported to be elevated in many cancerous states, which also involve rapid cellular growth, albeit in an unwanted and uncontrolled manner. The delineation of myristoylation-dependent cellular functions is still in a state of infancy, and many of the roles of the myristoylated proteins remain to be established. The development of cells of the leukocytic lineage represents a phase of rapid growth and development, and we have observed that NMT1 plays a role in this process. The current review outlines the roles of NMT1 in the growth and differentiation of the cells of leukocytic origin. The described studies clearly demonstrate the roles of NMT1 in the regulation of the developmental processes of the leukocytes cells and provide a basis for further research with the aim of unraveling the roles of protein myristoylation in both cellular and physiological context.
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Martin DDO, Beauchamp E, Berthiaume LG. Post-translational myristoylation: Fat matters in cellular life and death. Biochimie 2011; 93:18-31. [PMID: 21056615 DOI: 10.1016/j.biochi.2010.10.018] [Citation(s) in RCA: 152] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2010] [Accepted: 10/23/2010] [Indexed: 01/15/2023]
Abstract
Myristoylation corresponds to the irreversible covalent linkage of the 14-carbon saturated fatty acid, myristic acid, to the N-terminal glycine of many eukaryotic and viral proteins. It is catalyzed by N-myristoyltransferase. Typically, the myristate moiety participates in protein subcellular localization by facilitating protein-membrane interactions as well as protein-protein interactions. Myristoylated proteins are crucial components of a wide variety of functions, which include many signalling pathways, oncogenesis or viral replication. Initially, myristoylation was described as a co-translational reaction that occurs after the removal of the initiator methionine residue. However, it is now well established that myristoylation can also occur post-translationally in apoptotic cells. Indeed, during apoptosis hundreds of proteins are cleaved by caspases and in many cases this cleavage exposes an N-terminal glycine within a cryptic myristoylation consensus sequence, which can be myristoylated. The principal objective of this review is to provide an overview on the implication of myristoylation in health and disease with a special emphasis on post-translational myristoylation. In addition, new advancements in the detection and identification of myristoylated proteins are also briefly reviewed.
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Affiliation(s)
- Dale D O Martin
- Department of Cell Biology, School of Molecular and Systems Medicine, MSB-5-55, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
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22
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Arbiser JL. Translating cyclooxygenase signaling in patch heterozygote mice into a randomized clinical trial in basal cell carcinoma. Cancer Prev Res (Phila) 2010; 3:4-7. [PMID: 20051366 DOI: 10.1158/1940-6207.capr-09-0246] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
This different perspective on Tang et al. (beginning on p. 25 in this issue of the journal) discusses the pivotal role of cyclooxygenase (COX) signaling in the pathogenesis of basal cell carcinoma (BCC). These investigators conducted elegant experiments showing increased BCC burden in patch heterozygous mice overexpressing COX-2 in the epidermis. Genetic deletion of COX-1 or COX-2 resulted in a robust decrease in BCC burden in patch heterozygote mice. They then studied pharmacologic COX inhibition in mice and humans with loss of patch, finding a trend in humans toward decreased BCC burden. This finding has implications for public health.
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Affiliation(s)
- Jack L Arbiser
- Department of Dermatology, Emory University School of Medicine, Atlanta Veterans Administration Medical Center, GA 30322, USA.
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23
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Mills DR, Haskell MD, Callanan HM, Flanagan DL, Brilliant KE, Yang D, Hixson DC. Monoclonal antibody to novel cell surface epitope on Hsc70 promotes morphogenesis of bile ducts in newborn rat liver. Cell Stress Chaperones 2010; 15:39-53. [PMID: 19415527 PMCID: PMC2866973 DOI: 10.1007/s12192-009-0120-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2008] [Accepted: 04/19/2009] [Indexed: 12/30/2022] Open
Abstract
We previously described a cell surface reactive monoclonal antibody, MAb OC.10, which recognizes an epitope shared by rat fetal liver ductal cells, hepatic progenitor cells, mature cholangiocytes, and hepatocellular carcinomas (HCC). Here, intrasplenic injection of MAb OC.10 into newborn rats was shown by immunofluorescence microscopy to strongly label intrahepatic bile ducts. Furthermore, the in situ labeling of intrahepatic cholangiocytes by injecting MAb OC.10 increased the number of intraportal and intralobular bile ducts with well-defined lumens when compared to IgM-injected control animals. The antigen for MAb OC.10 was identified by mass spectrometry as Hsc70, a constitutively expressed heat shock protein belonging to the HSP70 family. Immunoblot analysis demonstrated that MAb OC.10 reacted with recombinant bovine Hsc70 protein, with protein immunoprecipitated from rat bile duct epithelial (BDE) cell lysates with monoclonal anti-Hsc70 antibody, and with Hsc70-FLAG protein over-expressed in human 293T cells. In addition, Hsc70-specific small interfering RNA reduced the amount of OC.10 antigen expressed in nucleofected BDE cells. Consistent with the specificity of MAb OC.10 for Hsc70, heat shock did not induce OC.10 expression in BDE cells, a characteristic of Hsp70. Immunofluorescence with BDE cells further suggested that MAb OC.10 binds a novel cell surface epitope of Hsc70. This was in contrast to a commercially available monoclonal anti-Hsc70 antibody that showed strong cytosolic reactivity. These findings demonstrate that presentation of the OC.10 epitope differs between cytosolic and surface forms of Hsc70 and may suggest distinct differences in protein conformation or epitope availability determined in part by protein-protein or protein-lipid interactions. Phage display and pepscan analysis mapped the epitope for MAb OC.10 to the N-terminal 340-384 amino acids of the ATPase domain of rat Hsc70. These findings suggest that MAb OC.10 recognizes an epitope on rat Hsc70 when presented on the cell surface that promotes morphogenic maturation of bile ducts in newborn rat liver. Furthermore, since we have shown previously that the OC.10 antigen is expressed on HCC subpopulations with oval cell characteristics, our current results indicate that Hsc70 has the potential to be expressed on the surface of certain tumor cells.
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Affiliation(s)
- David R. Mills
- Department of Medicine, Division of Hematology and Oncology, Rhode Island Hospital/The Warren Alpert Medical School of Brown University, Providence, RI 02903 USA
- Rhode Island Hospital, George Building Room 362, 593 Eddy Street, Providence, RI 02903 USA
| | - Michelle D. Haskell
- Department of Medicine, Division of Hematology and Oncology, Rhode Island Hospital/The Warren Alpert Medical School of Brown University, Providence, RI 02903 USA
| | - Helen M. Callanan
- Department of Medicine, Division of Hematology and Oncology, Rhode Island Hospital/The Warren Alpert Medical School of Brown University, Providence, RI 02903 USA
| | - Donna L. Flanagan
- Department of Medicine, Division of Hematology and Oncology, Rhode Island Hospital/The Warren Alpert Medical School of Brown University, Providence, RI 02903 USA
| | - Kate E. Brilliant
- Department of Medicine, Division of Hematology and Oncology, Rhode Island Hospital/The Warren Alpert Medical School of Brown University, Providence, RI 02903 USA
| | - DongQin Yang
- Department of Medicine, Division of Hematology and Oncology, Rhode Island Hospital/The Warren Alpert Medical School of Brown University, Providence, RI 02903 USA
| | - Douglas C. Hixson
- Department of Medicine, Division of Hematology and Oncology, Rhode Island Hospital/The Warren Alpert Medical School of Brown University, Providence, RI 02903 USA
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24
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Shrivastav A, Suri SS, Mohr R, Janardhan KS, Sharma RK, Singh B. Expression and activity of N-myristoyltransferase in lung inflammation of cattle and its role in neutrophil apoptosis. Vet Res 2009; 41:9. [PMID: 19796608 PMCID: PMC2775168 DOI: 10.1051/vetres/2009057] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2009] [Accepted: 10/01/2009] [Indexed: 01/11/2023] Open
Abstract
N-myristoyltransferase (NMT) attaches a 14 carbon fatty acid, myristic acid, to the N-terminal glycine residue of proteins. NMT exists in two isoforms NMT1 and NMT2. Myristoylated proteins play critical roles in protein-protein interactions, cell signaling and oncogenesis. Although elevated expression of NMT1 has been described in colorectal carcinoma, its expression and roles in normal and inflamed lungs of the cattle are unknown. Therefore, we investigated the expression and activity of NMT in a bovine model of lung inflammation induced with Mannheimia hemolytica and in vitro in neutrophils and macrophages. Western blots revealed increased expression of NMT1 in lungs from infected animals compared to control animals. Total NMT activity was reduced in inflamed lungs compared to control animals (p < 0.05) along with increased expression of enolase, a putative inhibitor of NMT. NMT1 staining was observed in the septum, vascular endothelium and the epithelium in the lungs from control as well as infected calves. NMT1 expression was intense in neutrophils in the necrotic areas in the inflamed lungs. Immuno-electron microscopy localized NMT1 in cytoplasm and nuclei of endothelium, pulmonary intravascular macrophages and airway epithelium. Total NMT activity and NMT1 expression were increased in neutrophils and macrophages exposed to Escherichia coli LPS in vitro. NMT knockdown increased apoptosis in activated neutrophils. This is the first report demonstrating expression of NMT in normal and inflamed lungs and a novel role for NMT in regulation of neutrophil lifespan.
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Affiliation(s)
- Anuraag Shrivastav
- Department of Pathology and Laboratory Medicine, College of Medicine and Saskatchewan Cancer Agency, 20 Campus Drive, Saskatoon, SK, Canada
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25
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Price HP, Güther MLS, Ferguson MAJ, Smith DF. Myristoyl-CoA:protein N-myristoyltransferase depletion in trypanosomes causes avirulence and endocytic defects. Mol Biochem Parasitol 2009; 169:55-8. [PMID: 19782106 PMCID: PMC2789243 DOI: 10.1016/j.molbiopara.2009.09.006] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2009] [Revised: 09/14/2009] [Accepted: 09/17/2009] [Indexed: 12/17/2022]
Abstract
The enzyme myristoyl-CoA:protein N-myristoyltransferase (NMT) catalyses the co-translational covalent attachment of the fatty acid myristate to the N-terminus of target proteins. NMT is known to be essential for viability in Trypanosoma brucei and Leishmania major. Here we describe phenotypic analysis of T. brucei bloodstream form cells following knockdown of NMT expression by tetracycline-inducible RNA interference. Cell death occurs from 72 h post-induction, with approximately 50% of cells displaying a defect in endocytic uptake by this time. The majority of these induced cells do not have an enlarged flagellar pocket typical of a block in endocytosis but vesicle accumulation around the flagellar pocket indicates a defect in vesicular progression following endocytic fusion. Induced parasites have a wild-type or slightly enlarged Golgi apparatus, unlike the phenotype of cells with reduced expression of a major N-myristoylated protein, ARL1. Critically we show that following NMT knockdown, T. brucei bloodstream form cells are unable to establish an infection in a mouse model, therefore providing further validation of this enzyme as a target for drug development.
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Affiliation(s)
- Helen P Price
- Centre for Immunology and Infection, Department of Biology, University of York, UK.
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