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Huang K, Wu H, Xu X, Wu L, Li Q, Han L. Identification of TGF-β-related genes in cardiac hypertrophy and heart failure based on single cell RNA sequencing. Aging (Albany NY) 2023; 15:7187-7218. [PMID: 37498303 PMCID: PMC10415570 DOI: 10.18632/aging.204901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 06/19/2023] [Indexed: 07/28/2023]
Abstract
BACKGROUND Heart failure (HF) remains a huge medical burden worldwide. Pathological cardiac hypertrophy is one of the most significant phenotypes of HF. Several studies have reported that the TGF-β pathway plays a double-sided role in HF. Therefore, TGF-β-related genes (TRGs) may be potential therapeutic targets for cardiac hypertrophy and HF. However, the roles of TRGs in HF at the single-cell level remain unclear. METHOD In this study, to analyze the expression pattern of TRGs during the progress of cardiac hypertrophy and HF, we used three public single-cell RNA sequencing datasets for HF (GSE161470, GSE145154, and GSE161153), one HF transcriptome data (GSE57338), and one hypertrophic cardiomyopathy transcriptome data (GSE141910). Weighted gene co-expression network analysis (WGCNA), functional enrichment analysis and machine learning algorithms were used to filter hub genes. Transverse aortic constriction mice model, CCK-8, wound healing assay, quantitative real-time PCR and western blotting were used to validate bioinformatics results. RESULTS We observed that cardiac fibroblasts (CFs) and endothelial cells showed high TGF-β activity during the progress of HF. Three modules (royalblue, brown4, and darkturquoize) were identified to be significantly associated with TRGs in HF. Six hub genes (TANC2, ADAMTS2, DYNLL1, MRC2, EGR1, and OTUD1) showed anomaly trend in cardiac hypertrophy. We further validated the regulation of the TGF-β-MYC-ADAMTS2 axis on CFs activation in vitro. CONCLUSIONS This study identified six hub genes (TANC2, ADAMTS2, DYNLL1, MRC2, EGR1, and OTUD1) by integrating scRNA and transcriptome data. These six hub genes might be therapeutic targets for cardiac hypertrophy and HF.
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Affiliation(s)
- Kai Huang
- Department of Cardiovascular Surgery, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Hao Wu
- Department of Cardiovascular Surgery, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Xiangyang Xu
- Department of Cardiovascular Surgery, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Lujia Wu
- Department of Cardiovascular Surgery, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Qin Li
- Department of Cardiovascular Surgery, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Lin Han
- Department of Cardiovascular Surgery, Changhai Hospital, Second Military Medical University, Shanghai, China
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2
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Talà A, Guerra F, Calcagnile M, Romano R, Resta SC, Paiano A, Chiariello M, Pizzolante G, Bucci C, Alifano P. HrpA anchors meningococci to the dynein motor and affects the balance between apoptosis and pyroptosis. J Biomed Sci 2022; 29:45. [PMID: 35765029 PMCID: PMC9241232 DOI: 10.1186/s12929-022-00829-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 06/22/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In Neisseria meningitidis the HrpA/HrpB two-partner secretion system (TPS) was implicated in diverse functions including meningococcal competition, biofilm formation, adherence to epithelial cells, intracellular survival and vacuolar escape. These diverse functions could be attributed to distinct domains of secreted HrpA. METHODS A yeast two-hybrid screening, in vitro pull-down assay and immunofluorescence microscopy experiments were used to investigate the interaction between HrpA and the dynein light-chain, Tctex-type 1 (DYNLT1). In silico modeling was used to analyze HrpA structure. Western blot analysis was used to investigate apoptotic and pyroptotic markers. RESULTS The HrpA carboxy-terminal region acts as a manganese-dependent cell lysin, while the results of a yeast two-hybrid screening demonstrated that the HrpA middle region has the ability to bind the dynein light-chain, Tctex-type 1 (DYNLT1). This interaction was confirmed by in vitro pull-down assay and immunofluorescence microscopy experiments showing co-localization of N. meningitidis with DYNLT1 in infected epithelial cells. In silico modeling revealed that the HrpA-M interface interacting with the DYNLT1 has similarity with capsid proteins of neurotropic viruses that interact with the DYNLT1. Indeed, we found that HrpA plays a key role in infection of and meningococcal trafficking within neuronal cells, and is implicated in the modulation of the balance between apoptosis and pyroptosis. CONCLUSIONS Our findings revealed that N. meningitidis is able to effectively infect and survive in neuronal cells, and that this ability is dependent on HrpA, which establishes a direct protein-protein interaction with DYNLTI in these cells, suggesting that the HrpA interaction with dynein could be fundamental for N. meningitidis spreading inside the neurons. Moreover, we found that the balance between apoptotic and pyroptotic pathways is heavily affected by HrpA.
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Affiliation(s)
- Adelfia Talà
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, Via Provinciale Monteroni n. 165, 73100, Lecce, Italy
| | - Flora Guerra
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, Via Provinciale Monteroni n. 165, 73100, Lecce, Italy
| | - Matteo Calcagnile
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, Via Provinciale Monteroni n. 165, 73100, Lecce, Italy
| | - Roberta Romano
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, Via Provinciale Monteroni n. 165, 73100, Lecce, Italy
| | - Silvia Caterina Resta
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, Via Provinciale Monteroni n. 165, 73100, Lecce, Italy
| | - Aurora Paiano
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, Via Provinciale Monteroni n. 165, 73100, Lecce, Italy
| | - Mario Chiariello
- Core Research Laboratory-Siena, Institute for Cancer Research and Prevention (ISPRO), 53100, Siena, Italy.,Institute of Clinical Physiology (IFC), National Research Council (CNR), 53100, Siena, Italy
| | - Graziano Pizzolante
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, Via Provinciale Monteroni n. 165, 73100, Lecce, Italy
| | - Cecilia Bucci
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, Via Provinciale Monteroni n. 165, 73100, Lecce, Italy.
| | - Pietro Alifano
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, Via Provinciale Monteroni n. 165, 73100, Lecce, Italy.
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3
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Pajkos M, Dosztányi Z. Functions of intrinsically disordered proteins through evolutionary lenses. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2021; 183:45-74. [PMID: 34656334 DOI: 10.1016/bs.pmbts.2021.06.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Protein sequences are the result of an evolutionary process that involves the balancing act of experimenting with novel mutations and selecting out those that have an undesirable functional outcome. In the case of globular proteins, the function relies on a well-defined conformation, therefore, there is a strong evolutionary pressure to preserve the structure. However, different evolutionary rules might apply for the group of intrinsically disordered regions and proteins (IDR/IDPs) that exist as an ensemble of fluctuating conformations. The function of IDRs can directly originate from their disordered state or arise through different types of molecular recognition processes. There is an amazing variety of ways IDRs can carry out their functions, and this is also reflected in their evolutionary properties. In this chapter we give an overview of the different types of evolutionary behavior of disordered proteins and associated functions in normal and disease settings.
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Affiliation(s)
- Mátyás Pajkos
- Department of Biochemistry, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Zsuzsanna Dosztányi
- Department of Biochemistry, ELTE Eötvös Loránd University, Budapest, Hungary.
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4
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Probert F, Yeo T, Zhou Y, Sealey M, Arora S, Palace J, Claridge TDW, Hillenbrand R, Oechtering J, Leppert D, Kuhle J, Anthony DC. Integrative biochemical, proteomics and metabolomics cerebrospinal fluid biomarkers predict clinical conversion to multiple sclerosis. Brain Commun 2021; 3:fcab084. [PMID: 33997784 PMCID: PMC8111065 DOI: 10.1093/braincomms/fcab084] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 03/18/2021] [Accepted: 03/19/2021] [Indexed: 12/23/2022] Open
Abstract
Eighty-five percent of multiple sclerosis cases begin with a discrete attack termed clinically isolated syndrome, but 37% of clinically isolated syndrome patients do not experience a relapse within 20 years of onset. Thus, the identification of biomarkers able to differentiate between individuals who are most likely to have a second clinical attack from those who remain in the clinically isolated syndrome stage is essential to apply a personalized medicine approach. We sought to identify biomarkers from biochemical, metabolic and proteomic screens that predict clinically defined conversion from clinically isolated syndrome to multiple sclerosis and generate a multi-omics-based algorithm with higher prognostic accuracy than any currently available test. An integrative multi-variate approach was applied to the analysis of cerebrospinal fluid samples taken from 54 individuals at the point of clinically isolated syndrome with 2-10 years of subsequent follow-up enabling stratification into clinical converters and non-converters. Leukocyte counts were significantly elevated at onset in the clinical converters and predict the occurrence of a second attack with 70% accuracy. Myo-inositol levels were significantly increased in clinical converters while glucose levels were decreased, predicting transition to multiple sclerosis with accuracies of 72% and 63%, respectively. Proteomics analysis identified 89 novel gene products related to conversion. The identified biochemical and protein biomarkers were combined to produce an algorithm with predictive accuracy of 83% for the transition to clinically defined multiple sclerosis, outperforming any individual biomarker in isolation including oligoclonal bands. The identified protein biomarkers are consistent with an exaggerated immune response, perturbed energy metabolism and multiple sclerosis pathology in the clinical converter group. The new biomarkers presented provide novel insight into the molecular pathways promoting disease while the multi-omics algorithm provides a means to more accurately predict whether an individual is likely to convert to clinically defined multiple sclerosis.
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Affiliation(s)
- Fay Probert
- Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK.,Department of Chemistry, University of Oxford, Oxford OX1 3TA, UK
| | - Tianrong Yeo
- Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK.,Department of Neurology, National Neuroscience Institute, Singapore 308437, Singapore
| | - Yifan Zhou
- Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK
| | - Megan Sealey
- Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK
| | - Siddharth Arora
- Mathematical Institute, University of Oxford, Oxford OX2 6GG, UK
| | - Jacqueline Palace
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
| | | | | | - Johanna Oechtering
- Neurology, Departments of Medicine, Clinical Research and Biomedicine, University Hospital Basel, University of Basel, Basel CH-4031, Switzerland
| | - David Leppert
- Neurology, Departments of Medicine, Clinical Research and Biomedicine, University Hospital Basel, University of Basel, Basel CH-4031, Switzerland
| | - Jens Kuhle
- Neurology, Departments of Medicine, Clinical Research and Biomedicine, University Hospital Basel, University of Basel, Basel CH-4031, Switzerland
| | - Daniel C Anthony
- Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK
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5
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Silencing of Tctex1 impairs autophagy lysosomal degradation of α-synuclein and cell viability. Neuroreport 2018; 29:385-392. [PMID: 29406369 DOI: 10.1097/wnr.0000000000000979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Tctex1 is an important element of the dynein motor unit in mammalian cells that helps move targets along microtubules and toward the centrosome for degradation. Here, we analyzed the role of Tctex1 in the α-synuclein autophagy-lysosome degradation pathway using Tctex1-siRNA in SH-SY5Y cells. Results showed that siRNA silencing of Tctex1 suppressed cellular viability and promoted cell apoptosis. Protein and mRNA expression of Tctex1 and dynein decreased after Tctex1 knockdown, whereas α-synuclein, LC3-II, and LAMP2 increased. Consistently, fluorescence intensity of Tctex1 was weaker in siRNA-Tctex1-transfected cells, and that of α-synuclein, LC3-II, and LAMP2 was increased. Tctex1 inhibition reduced cell viability and promoted apoptosis. These results show that Tctex1 plays an important role in α-synuclein autophagic degradation and in maintaining cellular homeostasis.
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6
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Structural atlas of dynein motors at atomic resolution. Biophys Rev 2018; 10:677-686. [PMID: 29478092 DOI: 10.1007/s12551-018-0402-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Accepted: 02/05/2018] [Indexed: 12/17/2022] Open
Abstract
Dynein motors are biologically important bio-nanomachines, and many atomic resolution structures of cytoplasmic dynein components from different organisms have been analyzed by X-ray crystallography, cryo-EM, and NMR spectroscopy. This review provides a historical perspective of structural studies of cytoplasmic and axonemal dynein including accessory proteins. We describe representative structural studies of every component of dynein and summarize them as a structural atlas that classifies the cytoplasmic and axonemal dyneins. Based on our review of all dynein structures in the Protein Data Bank, we raise two important points for understanding the two types of dynein motor and discuss the potential prospects of future structural studies.
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7
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Sandí MJ, Marshall CB, Balan M, Coyaud É, Zhou M, Monson DM, Ishiyama N, Chandrakumar AA, La Rose J, Couzens AL, Gingras AC, Raught B, Xu W, Ikura M, Morrison DK, Rottapel R. MARK3-mediated phosphorylation of ARHGEF2 couples microtubules to the actin cytoskeleton to establish cell polarity. Sci Signal 2017; 10:10/503/eaan3286. [PMID: 29089450 DOI: 10.1126/scisignal.aan3286] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The PAR-1-MARK pathway controls cell polarity through the phosphorylation of microtubule-associated proteins. Rho-Rac guanine nucleotide exchange factor 2 (ARHGEF2), which activates Ras homolog family member A (RHOA), is anchored to the microtubule network and sequestered in an inhibited state through binding to dynein light chain Tctex-1 type 1 (DYNLT1). We showed in mammalian cells that liver kinase B1 (LKB1) activated the microtubule affinity-regulating kinase 3 (MARK3), which in turn phosphorylated ARHGEF2 at Ser151 This modification disrupted the interaction between ARHGEF2 and DYNLT1 by generating a 14-3-3 binding site in ARHGEF2, thus causing ARHGEF2 to dissociate from microtubules. Phosphorylation of ARHGEF2 by MARK3 stimulated RHOA activation and the formation of stress fibers and focal adhesions, and was required for organized cellular architecture in three-dimensional culture. Protein phosphatase 2A (PP2A) dephosphorylated Ser151 in ARHGEF2 to restore the inhibited state. Thus, we have identified a regulatory switch controlled by MARK3 that couples microtubules to the actin cytoskeleton to establish epithelial cell polarity through ARHGEF2.
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Affiliation(s)
- María-José Sandí
- Princess Margaret Cancer Centre, University Health Network, 101 College Street, Princess Margaret Cancer Research Tower, Toronto, Ontario M5G 1L7, Canada
| | - Christopher B Marshall
- Princess Margaret Cancer Centre, University Health Network, 101 College Street, Princess Margaret Cancer Research Tower, Toronto, Ontario M5G 1L7, Canada
| | - Marc Balan
- Princess Margaret Cancer Centre, University Health Network, 101 College Street, Princess Margaret Cancer Research Tower, Toronto, Ontario M5G 1L7, Canada.,Department of Medical Biophysics, University of Toronto, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada
| | - Étienne Coyaud
- Princess Margaret Cancer Centre, University Health Network, 101 College Street, Princess Margaret Cancer Research Tower, Toronto, Ontario M5G 1L7, Canada
| | - Ming Zhou
- Center for Cancer Research, National Cancer Institute at Frederick, P.O. Box B, Frederick, MD 21702, USA
| | - Daniel M Monson
- Center for Cancer Research, National Cancer Institute at Frederick, P.O. Box B, Frederick, MD 21702, USA
| | - Noboru Ishiyama
- Princess Margaret Cancer Centre, University Health Network, 101 College Street, Princess Margaret Cancer Research Tower, Toronto, Ontario M5G 1L7, Canada
| | - Arun A Chandrakumar
- Princess Margaret Cancer Centre, University Health Network, 101 College Street, Princess Margaret Cancer Research Tower, Toronto, Ontario M5G 1L7, Canada.,Department of Medical Biophysics, University of Toronto, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada
| | - José La Rose
- Princess Margaret Cancer Centre, University Health Network, 101 College Street, Princess Margaret Cancer Research Tower, Toronto, Ontario M5G 1L7, Canada
| | - Amber L Couzens
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario M5G 1X5, Canada
| | - Anne-Claude Gingras
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario M5G 1X5, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Brian Raught
- Princess Margaret Cancer Centre, University Health Network, 101 College Street, Princess Margaret Cancer Research Tower, Toronto, Ontario M5G 1L7, Canada.,Department of Medical Biophysics, University of Toronto, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada
| | - Wei Xu
- Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada.,Department of Biostatistics, Princess Margaret Cancer Centre, Toronto, Ontario, Canada
| | - Mitsuhiko Ikura
- Princess Margaret Cancer Centre, University Health Network, 101 College Street, Princess Margaret Cancer Research Tower, Toronto, Ontario M5G 1L7, Canada.,Department of Medical Biophysics, University of Toronto, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada
| | - Deborah K Morrison
- Center for Cancer Research, National Cancer Institute at Frederick, P.O. Box B, Frederick, MD 21702, USA
| | - Robert Rottapel
- Princess Margaret Cancer Centre, University Health Network, 101 College Street, Princess Margaret Cancer Research Tower, Toronto, Ontario M5G 1L7, Canada. .,Department of Medical Biophysics, University of Toronto, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada.,Department of Medicine, University of Toronto, Toronto, Ontario M5S 1A8, Canada.,Department of Immunology, University of Toronto, Toronto, Ontario M5S 1A8, Canada.,Division of Rheumatology, St. Michael's Hospital, 30 Bond Street, Toronto, Ontario M5B 1W8, Canada
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8
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Costas-Insua C, Merino-Gracia J, Aicart-Ramos C, Rodríguez-Crespo I. Subcellular Targeting of Nitric Oxide Synthases Mediated by Their N-Terminal Motifs. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2017; 111:165-195. [PMID: 29459031 DOI: 10.1016/bs.apcsb.2017.07.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
From a catalytic point of view, the three mammalian nitric oxide synthases (NOSs) function in an almost identical way. The N-terminal oxygenase domain catalyzes the conversion of l-arginine to l-citrulline plus ·NO in two sequential oxidation steps. Once l-arginine binds to the active site positioned above the heme moiety, two consecutive monooxygenation reactions take place. In the first step, l-arginine is hydroxylated to make Nω-hydroxy-l-arginine in a process that requires 1 molecule of NADPH and 1 molecule of O2 per mol of l-arginine reacted. In the second step, Nω-hydroxy-l-arginine, never leaving the active site, is oxidized to ·NO plus l-citrulline and 1 molecule of O2 and 0.5 molecules of NADPH are consumed. Since nitric oxide is an important signaling molecule that participates in a number of biological processes, including neurotransmission, vasodilation, and immune response, synthesis and release of ·NO in vivo must be exquisitely regulated both in time and in space. Hence, NOSs have evolved introducing in their amino acid sequences subcellular targeting motifs, most of them located at their N-termini. Deletion studies performed on recombinant, purified NOSs have revealed that part of the N-terminus of all three NOS can be eliminated with the resulting mutant enzymes still being catalytically active. Likewise, NOS isoforms lacking part of their N-terminus when transfected in cells render mislocalized, active proteins. In this review we will comment on the current knowledge of these subcellular targeting signals present in nNOS, iNOS, and eNOS.
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Oyama LB, Crochet JA, Edwards JE, Girdwood SE, Cookson AR, Fernandez-Fuentes N, Hilpert K, Golyshin PN, Golyshina OV, Privé F, Hess M, Mantovani HC, Creevey CJ, Huws SA. Buwchitin: A Ruminal Peptide with Antimicrobial Potential against Enterococcus faecalis. Front Chem 2017; 5:51. [PMID: 28748180 PMCID: PMC5506224 DOI: 10.3389/fchem.2017.00051] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 06/27/2017] [Indexed: 11/14/2022] Open
Abstract
Antimicrobial peptides (AMPs) are gaining popularity as alternatives for treatment of bacterial infections and recent advances in omics technologies provide new platforms for AMP discovery. We sought to determine the antibacterial activity of a novel antimicrobial peptide, buwchitin, against Enterococcus faecalis. Buwchitin was identified from a rumen bacterial metagenome library, cloned, expressed and purified. The antimicrobial activity of the recombinant peptide was assessed using a broth microdilution susceptibility assay to determine the peptide's killing kinetics against selected bacterial strains. The killing mechanism of buwchitin was investigated further by monitoring its ability to cause membrane depolarization (diSC3(5) method) and morphological changes in E. faecalis cells. Transmission electron micrographs of buwchitin treated E. faecalis cells showed intact outer membranes with blebbing, but no major damaging effects and cell morphology changes. Buwchitin had negligible cytotoxicity against defibrinated sheep erythrocytes. Although no significant membrane leakage and depolarization was observed, buwchitin at minimum inhibitory concentration (MIC) was bacteriostatic against E. faecalis cells and inhibited growth in vitro by 70% when compared to untreated cells. These findings suggest that buwchitin, a rumen derived peptide, has potential for antimicrobial activity against E. faecalis.
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Affiliation(s)
- Linda B Oyama
- Institute of Biological Environmental and Rural Sciences, Aberystwyth UniversityAberystwyth, United Kingdom
| | - Jean-Adrien Crochet
- Institute of Biological Environmental and Rural Sciences, Aberystwyth UniversityAberystwyth, United Kingdom
| | - Joan E Edwards
- Institute of Biological Environmental and Rural Sciences, Aberystwyth UniversityAberystwyth, United Kingdom
| | - Susan E Girdwood
- Institute of Biological Environmental and Rural Sciences, Aberystwyth UniversityAberystwyth, United Kingdom
| | - Alan R Cookson
- Institute of Biological Environmental and Rural Sciences, Aberystwyth UniversityAberystwyth, United Kingdom
| | - Narcis Fernandez-Fuentes
- Institute of Biological Environmental and Rural Sciences, Aberystwyth UniversityAberystwyth, United Kingdom
| | - Kai Hilpert
- Institute of Infection and Immunity, St George's University of LondonLondon, United Kingdom
| | - Peter N Golyshin
- School of Biological Sciences, Bangor UniversityBangor, United Kingdom
| | - Olga V Golyshina
- School of Biological Sciences, Bangor UniversityBangor, United Kingdom
| | - Florence Privé
- Institute of Biological Environmental and Rural Sciences, Aberystwyth UniversityAberystwyth, United Kingdom
| | - Matthias Hess
- College of Agricultural and Environmental Sciences, University of California, DavisDavis, CA, United States
| | | | - Christopher J Creevey
- Institute of Biological Environmental and Rural Sciences, Aberystwyth UniversityAberystwyth, United Kingdom
| | - Sharon A Huws
- Medical Biology Centre, School of Biological Sciences, Queen's University BelfastBelfast, United Kingdom
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