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Lange KI, Best S, Tsiropoulou S, Berry I, Johnson CA, Blacque OE. Interpreting ciliopathy-associated missense variants of uncertain significance (VUS) in Caenorhabditis elegans. Hum Mol Genet 2022; 31:1574-1587. [PMID: 34964473 PMCID: PMC9122650 DOI: 10.1093/hmg/ddab344] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 11/16/2021] [Accepted: 11/17/2021] [Indexed: 12/26/2022] Open
Abstract
Better methods are required to interpret the pathogenicity of disease-associated variants of uncertain significance (VUS), which cannot be actioned clinically. In this study, we explore the use of an animal model (Caenorhabditis elegans) for in vivo interpretation of missense VUS alleles of TMEM67, a cilia gene associated with ciliopathies. CRISPR/Cas9 gene editing was used to generate homozygous knock-in C. elegans worm strains carrying TMEM67 patient variants engineered into the orthologous gene (mks-3). Quantitative phenotypic assays of sensory cilia structure and function (neuronal dye filling, roaming and chemotaxis assays) measured how the variants impacted mks-3 gene function. Effects of the variants on mks-3 function were further investigated by looking at MKS-3::GFP localization and cilia ultrastructure. The quantitative assays in C. elegans accurately distinguished between known benign (Asp359Glu, Thr360Ala) and known pathogenic (Glu361Ter, Gln376Pro) variants. Analysis of eight missense VUS generated evidence that three are benign (Cys173Arg, Thr176Ile and Gly979Arg) and five are pathogenic (Cys170Tyr, His782Arg, Gly786Glu, His790Arg and Ser961Tyr). Results from worms were validated by a genetic complementation assay in a human TMEM67 knock-out hTERT-RPE1 cell line that tests a TMEM67 signalling function. We conclude that efficient genome editing and quantitative functional assays in C. elegans make it a tractable in vivo animal model for rapid, cost-effective interpretation of ciliopathy-associated missense VUS alleles.
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Affiliation(s)
- Karen I Lange
- School of Biomolecular and Biomedical Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - Sunayna Best
- Division of Molecular Medicine, Leeds Institute of Medical Research, University of Leeds, Leeds, West Yorkshire, UK
| | - Sofia Tsiropoulou
- School of Biomolecular and Biomedical Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - Ian Berry
- Bristol Genetics Laboratory, Pathology Sciences, Southmead Hospital, Bristol BS10 5NB, UK
| | - Colin A Johnson
- Division of Molecular Medicine, Leeds Institute of Medical Research, University of Leeds, Leeds, West Yorkshire, UK
| | - Oliver E Blacque
- School of Biomolecular and Biomedical Science, University College Dublin, Belfield, Dublin 4, Ireland
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Park K, Li C, Tsiropoulou S, Gonçalves J, Kondratev C, Pelletier L, Blacque OE, Leroux MR. CDKL kinase regulates the length of the ciliary proximal segment. Curr Biol 2021; 31:2359-2373.e7. [PMID: 33857430 DOI: 10.1016/j.cub.2021.03.068] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 01/25/2021] [Accepted: 03/19/2021] [Indexed: 11/16/2022]
Abstract
Cilia are organelles found throughout most unicellular eukaryotes and different metazoan cell types. To accomplish their essential roles in cell motility, fluid flow, and signaling, cilia are divided into subcompartments with variable structures, compositions, and functions. How these specific subcompartments are built remains almost completely unexplored. Here, we show that C. elegans CDKL-1, related to the human CDKL kinase family (CDKL1/CDKL2/CDKL3/CDKL4/CDKL5), specifically controls the length of the proximal segment, a ciliary subdomain conserved in evolution from Tetrahymena motile cilia to C. elegans chemosensory, mammalian olfactory, and photoreceptor non-motile cilia. CDKL-1 associates with intraflagellar transport (IFT), influences the distribution of the IFT anterograde motors heterotrimeric kinesin-II and homodimeric OSM-3-kinesin/KIF17 in the proximal segment, and shifts the boundary between the proximal and distal segments (PS/DS boundary). CDKL-1 appears to function independently from several factors that influence cilium length, namely the kinases DYF-5 (mammalian CILK1/MAK) and NEKL-1 (NEK9), as well as the depolymerizing kinesins KLP-13 (KIF19) and KLP-7 (KIF2). However, a different kinase, DYF-18 (CCRK), is needed for the correct localization and function of CDKL-1 and similarly influences the length of the proximal segment. Loss of CDKL-1, which affects proximal segment length without impairing overall ciliary microtubule structural integrity, also impairs cilium-dependent processes, namely cGMP-signaling-dependent body length control and CO2 avoidance. Collectively, our findings suggest that cilium length is regulated by various pathways and that the IFT-associated kinase CDKL-1 is essential for the construction of a specific ciliary compartment and contributes to development and sensory physiology.
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Affiliation(s)
- Kwangjin Park
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada; Centre for Cell Biology, Development, and Disease, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Chunmei Li
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada; Centre for Cell Biology, Development, and Disease, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Sofia Tsiropoulou
- School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - João Gonçalves
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada
| | - Christine Kondratev
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada; Centre for Cell Biology, Development, and Disease, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Laurence Pelletier
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Oliver E Blacque
- School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - Michel R Leroux
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada; Centre for Cell Biology, Development, and Disease, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.
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Lange KI, Tsiropoulou S, Kucharska K, Blacque OE. Interpreting the pathogenicity of Joubert syndrome missense variants in Caenorhabditis elegans. Dis Model Mech 2021; 14:dmm.046631. [PMID: 33234550 PMCID: PMC7859701 DOI: 10.1242/dmm.046631] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 11/13/2020] [Indexed: 12/26/2022] Open
Abstract
Ciliopathies are inherited disorders caused by defects in motile and non-motile (primary) cilia. Ciliopathy syndromes and associated gene variants are often highly pleiotropic and represent exemplars for interrogating genotype-phenotype correlations. Towards understanding disease mechanisms in the context of ciliopathy mutations, we have used a leading model organism for cilia and ciliopathy research, Caenorhabditis elegans, together with gene editing, to characterise two missense variants (P74S and G155S) in mksr-2/B9D2 associated with Joubert syndrome (JBTS). B9D2 functions within the Meckel syndrome (MKS) module at the ciliary base transition zone (TZ) compartment and regulates the molecular composition and sensory/signalling functions of the cilium. Quantitative assays of cilium/TZ structure and function, together with knock-in reporters, confirm that both variant alleles are pathogenic in worms. G155S causes a more severe overall phenotype and disrupts endogenous MKSR-2 organisation at the TZ. Recapitulation of the patient biallelic genotype shows that compound heterozygous worms phenocopy worms homozygous for P74S. The P74S and G155S alleles also reveal evidence of a very close functional association between the B9D2-associated B9 complex and MKS-2/TMEM216. Together, these data establish C. elegans as a model for interpreting JBTS mutations and provide further insight into MKS module organisation. This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Karen I Lange
- School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Dublin 4, Ireland
| | - Sofia Tsiropoulou
- School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Dublin 4, Ireland
| | - Katarzyna Kucharska
- School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Dublin 4, Ireland
| | - Oliver E Blacque
- School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Dublin 4, Ireland
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Akella JS, Carter SP, Nguyen K, Tsiropoulou S, Moran AL, Silva M, Rizvi F, Kennedy BN, Hall DH, Barr MM, Blacque OE. Ciliary Rab28 and the BBSome negatively regulate extracellular vesicle shedding. eLife 2020; 9:e50580. [PMID: 32101165 PMCID: PMC7043889 DOI: 10.7554/elife.50580] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 02/02/2020] [Indexed: 12/15/2022] Open
Abstract
Cilia both receive and send information, the latter in the form of extracellular vesicles (EVs). EVs are nano-communication devices that influence cell, tissue, and organism behavior. Mechanisms driving ciliary EV biogenesis are almost entirely unknown. Here, we show that the ciliary G-protein Rab28, associated with human autosomal recessive cone-rod dystrophy, negatively regulates EV levels in the sensory organs of Caenorhabditis elegans in a cilia specific manner. Sequential targeting of lipidated Rab28 to periciliary and ciliary membranes is highly dependent on the BBSome and the prenyl-binding protein phosphodiesterase 6 subunit delta (PDE6D), respectively, and BBSome loss causes excessive and ectopic EV production. We also find that EV defective mutants display abnormalities in sensory compartment morphogenesis. Together, these findings reveal that Rab28 and the BBSome are key in vivo regulators of EV production at the periciliary membrane and suggest that EVs may mediate signaling between cilia and glia to shape sensory organ compartments. Our data also suggest that defects in the biogenesis of cilia-related EVs may contribute to human ciliopathies.
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Affiliation(s)
- Jyothi S Akella
- Department of Genetics and Human Genetics Institute of New Jersey, Rutgers UniversityPiscatawayUnited States
| | - Stephen P Carter
- School of Biomolecular and Biomedical Science, Conway Institute, University College DublinDublinIreland
| | - Ken Nguyen
- Center for C. elegans Anatomy, Albert Einstein College of MedicineBronxUnited States
| | - Sofia Tsiropoulou
- School of Biomolecular and Biomedical Science, Conway Institute, University College DublinDublinIreland
| | - Ailis L Moran
- School of Biomolecular and Biomedical Science, Conway Institute, University College DublinDublinIreland
| | - Malan Silva
- Department of Genetics and Human Genetics Institute of New Jersey, Rutgers UniversityPiscatawayUnited States
- Department of Biology, University of UtahSalt Lake CityUnited States
| | - Fatima Rizvi
- Department of Genetics and Human Genetics Institute of New Jersey, Rutgers UniversityPiscatawayUnited States
| | - Breandan N Kennedy
- School of Biomolecular and Biomedical Science, Conway Institute, University College DublinDublinIreland
| | - David H Hall
- Center for C. elegans Anatomy, Albert Einstein College of MedicineBronxUnited States
| | - Maureen M Barr
- Department of Genetics and Human Genetics Institute of New Jersey, Rutgers UniversityPiscatawayUnited States
| | - Oliver E Blacque
- School of Biomolecular and Biomedical Science, Conway Institute, University College DublinDublinIreland
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Camargo LL, Harvey AP, Rios FJ, Tsiropoulou S, Da Silva RDNO, Cao Z, Graham D, McMaster C, Burchmore RJ, Hartley RC, Bulleid N, Montezano AC, Touyz RM. Vascular Nox (NADPH Oxidase) Compartmentalization, Protein Hyperoxidation, and Endoplasmic Reticulum Stress Response in Hypertension. Hypertension 2018; 72:235-246. [PMID: 29844144 DOI: 10.1161/hypertensionaha.118.10824] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 01/21/2018] [Accepted: 04/27/2018] [Indexed: 12/31/2022]
Abstract
Vascular Nox (NADPH oxidase)-derived reactive oxygen species and endoplasmic reticulum (ER) stress have been implicated in hypertension. However, relationships between these processes are unclear. We hypothesized that Nox isoforms localize in a subcellular compartment-specific manner, contributing to oxidative and ER stress, which influence the oxidative proteome and vascular function in hypertension. Nox compartmentalization (cell fractionation), O2- (lucigenin), H2O2 (amplex red), reversible protein oxidation (sulfenylation), irreversible protein oxidation (protein tyrosine phosphatase, peroxiredoxin oxidation), and ER stress (PERK [protein kinase RNA-like endoplasmic reticulum kinase], IRE1α [inositol-requiring enzyme 1], and phosphorylation/oxidation) were studied in spontaneously hypertensive rat (SHR) vascular smooth muscle cells (VSMCs). VSMC proliferation was measured by fluorescence-activated cell sorting, and vascular reactivity assessed in stroke-prone SHR arteries by myography. Noxs were downregulated by short interfering RNA and pharmacologically. In SHR, Noxs were localized in specific subcellular regions: Nox1 in plasma membrane and Nox4 in ER. In SHR, oxidative stress was associated with increased protein sulfenylation and hyperoxidation of protein tyrosine phosphatases and peroxiredoxins. Inhibition of Nox1 (NoxA1ds), Nox1/4 (GKT137831), and ER stress (4-phenylbutyric acid/tauroursodeoxycholic acid) normalized SHR vascular reactive oxygen species generation. GKT137831 reduced IRE1α sulfenylation and XBP1 (X-box binding protein 1) splicing in SHR. Increased VSMC proliferation in SHR was normalized by GKT137831, 4-phenylbutyric acid, and STF083010 (IRE1-XBP1 disruptor). Hypercontractility in the stroke-prone SHR was attenuated by 4-phenylbutyric acid. We demonstrate that protein hyperoxidation in hypertension is associated with oxidative and ER stress through upregulation of plasmalemmal-Nox1 and ER-Nox4. The IRE1-XBP1 pathway of the ER stress response is regulated by Nox4/reactive oxygen species and plays a role in the hyperproliferative VSMC phenotype in SHR. Our study highlights the importance of Nox subcellular compartmentalization and interplay between cytoplasmic reactive oxygen species and ER stress response, which contribute to the VSMC oxidative proteome and vascular dysfunction in hypertension.
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Affiliation(s)
- Livia L Camargo
- From the Institute of Cardiovascular and Medical Sciences (L.L.C., A.P.H., F.J.R., S.T., D.G., A.C.M., R.M.T.)
| | - Adam P Harvey
- From the Institute of Cardiovascular and Medical Sciences (L.L.C., A.P.H., F.J.R., S.T., D.G., A.C.M., R.M.T.)
| | - Francisco J Rios
- From the Institute of Cardiovascular and Medical Sciences (L.L.C., A.P.H., F.J.R., S.T., D.G., A.C.M., R.M.T.)
| | - Sofia Tsiropoulou
- From the Institute of Cardiovascular and Medical Sciences (L.L.C., A.P.H., F.J.R., S.T., D.G., A.C.M., R.M.T.)
| | | | - Zhenbo Cao
- The Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences (Z.C., N.B.)
| | - Delyth Graham
- From the Institute of Cardiovascular and Medical Sciences (L.L.C., A.P.H., F.J.R., S.T., D.G., A.C.M., R.M.T.)
| | - Claire McMaster
- WestCHEM School of Chemistry (C.M., R.C.H.), University of Glasgow, Scotland, United Kingdom
| | - Richard J Burchmore
- Institute of Infection, Immunity and Inflammation, Polyomics Facility (R.J.B.)
| | - Richard C Hartley
- WestCHEM School of Chemistry (C.M., R.C.H.), University of Glasgow, Scotland, United Kingdom
| | - Neil Bulleid
- The Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences (Z.C., N.B.)
| | - Augusto C Montezano
- From the Institute of Cardiovascular and Medical Sciences (L.L.C., A.P.H., F.J.R., S.T., D.G., A.C.M., R.M.T.)
| | - Rhian M Touyz
- From the Institute of Cardiovascular and Medical Sciences (L.L.C., A.P.H., F.J.R., S.T., D.G., A.C.M., R.M.T.)
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Camargo LL, Montezano AC, Harvey A, Tsiropoulou S, Hood K, Cao Z, Burchmore R, Hartley R, Bulleid N, Touyz RM. Abstract P217: Nox Compartmentalization, Protein Oxidation and ER Stress in Vascular Smooth Muscle Cells in Hypertension. Hypertension 2017. [DOI: 10.1161/hyp.70.suppl_1.p217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In hypertension, activation of NADPH oxidases (Noxs) is associated with oxidative stress and vascular dysfunction. The exact role of each isoform in hypertension-associated vascular injury is still unclear. We investigated the compartmentalization of Noxs in VSMC from resistance arteries of Wistar Kyoto (WKY) and spontaneously hypertensive rats (SHR). Expression of Nox1 and Nox4 was increased in SHR cells (96.6±28.7% and 48.2±21.2% vs WKY, p<0.05), as well as basal ROS levels measured by chemiluminescence (110.2±26.4% vs WKY, p<0.05) and amplex red (105.2±33.2% vs WKY, p<0.05). Phosphorylation of unfolded protein response activators, PERK and IRE1α, and expression of ER chaperone BiP were elevated in SHR cells (p<0.05 vs WKY), indicating activation of ER stress response. Immunoblotting after organelle fractionation demonstrated that Noxs are expressed in an organelle-specific manner, with Nox1, 2 and 4 present in plasma membrane, ER and nucleus, but not in mitochondria. In SHR cells, NoxA1ds (Nox1 inhibitor, 10μM) and GKT136901 (Nox1/4 inhibitor, 10μM) decreased AngII-induced ROS levels (p<0.001 vs Ctl). Additionally, mito-tempol (mitochondrial-targeted antioxidant, 50nM) and 4-PBA (ER stress inhibitor, 1mM) decreased basal ROS levels in SHR cells (p<0.05 vs Ctl). Furthermore, oxidation of the antioxidant enzymes Peroxiredoxins (Prx) was increased in SHRSP compared to WKY (2.51±0.14 vs 0.56±0.07, p<0.001). One-dimensional isoelectric focusing revealed that cytosolic Prx2 and mitochondrial Prx3 were more oxidized in SHRSP than WKY cells. Using a biotin-tagged dimedone-based probe (DCP-Bio) we identified oxidation of ER stress proteins BiP and IRE1. To investigate the effect of protein oxidation in vascular function, vascular reactivity was evaluated in isolated mesenteric arteries. Inhibition of general oxidation (DTT 1mM; Emax: 111.7±33.1) and peroxiredoxin (Conoidin A 10nM; Emax: 116.0±7.3) reduces vascular contraction in response to noradrenalin in WKY rats (Emax: 166.6±30.2; p<0.05). These findings suggest an important role for Nox1/4 in redox-dependent organelle dysfunction and post-translational modification of proteins, processes that may play an important role in vascular dysfunction in hypertension.
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Affiliation(s)
| | | | | | | | - Katie Hood
- Univ of Glasgow, Glasgow, United Kingdom
| | - Zhenbo Cao
- Univ of Glasgow, Glasgow, United Kingdom
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Lucca Camargo LD, Montezano AC, Tsiropoulou S, Harvey A, Hood K, Cao Z, Burchmore R, Bulleid N, Touyz R. 181 Nox compartmentalization and protein oxidation in vascular smooth muscle cells – implications in vascular dysfunction in hypertension. Heart 2017. [DOI: 10.1136/heartjnl-2017-311726.179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Tsiropoulou S, Touyz RM. Assessment of Protein Carbonylation and Protein Tyrosine Phosphatase (PTP) Oxidation in Vascular Smooth Muscle Cells (VSMCs) Using Immunoblotting Approaches. Methods Mol Biol 2017; 1614:31-46. [PMID: 28500593 DOI: 10.1007/978-1-4939-7030-8_3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Post-translational modification of proteins, such as phosphorylation and oxidation, plays a major role in cellular signaling by influencing protein structure and function. In vascular cells, in addition to influencing phosphorylation, angiotensin II (Ang II) induces oxidation of proteins, important in redox signaling in the cardiovascular and renal systems. The present chapter describes immunoblotting approaches to assess irreversible protein carbonylation and protein tyrosine phosphatase (PTPs) oxidation status in the proteome of vascular smooth muscle cells (VSMC).Protein carbonylation is generally measured using the OxyBlot™ approach, whereby derivatization of protein carbonyl groups (C = O) on oxidized amino acids by dinitrophenylhydrazine (DNPH) results in the formation of a stable dinitrophenyl (DNP) hydrazone product. The samples are analyzed by SDS-PAGE and a primary antibody raised against the DNP moiety is used to determine levels of irreversible protein carbonylation in the sample by immunoblotting.Oxidation of PTPs can be evaluated using a monoclonal antibody against the "hyperoxidized" (SO3H) catalytic site of these enzymes. The described methodology offers the ability to discriminate between irreversible (SO3H) and reversible (SOH) PTP oxidation states. Initially, the free unmodified PTP-thiols (S-) are alkylated and the sample is split into two. One part is used to assess the PTP-SO3H form. In the other part reversibly modified PTP-thiols are first reduced and then hyperoxidized by pervanadate (PV). Both untreated and PV-treated samples are analyzed by SDS-PAGE and "hyperoxidized" PTPs are detected by immunoblotting. The proportion of reversibly oxidized PTP-SOH fraction is determined by the difference between the signals in untreated and the PV-treated samples.The above immunoassays provide general approaches to detect and quantify global levels of irreversible protein oxidation and of irreversibly/reversibly oxidized PTPs in any (patho)physiological context. Characterization of the global redox status is essential to better understand the redox-sensitive mechanisms underlying chronic diseases associated with oxidative stress. This is particularly important in systems influenced by the renin angiotensin system, because Ang II is a potent inducer of oxidative stress and redox signaling.
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Affiliation(s)
- Sofia Tsiropoulou
- Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, 126 University Place, Glasgow, G12 8TA, UK
| | - Rhian M Touyz
- Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, 126 University Place, Glasgow, G12 8TA, UK.
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Nguyen Dinh Cat A, Antunes TT, Callera GE, Sanchez A, Tsiropoulou S, Dulak-Lis MG, Anagnostopoulou A, He Y, Montezano AC, Jaisser F, Touyz RM. Adipocyte-Specific Mineralocorticoid Receptor Overexpression in Mice Is Associated With Metabolic Syndrome and Vascular Dysfunction: Role of Redox-Sensitive PKG-1 and Rho Kinase. Diabetes 2016; 65:2392-403. [PMID: 27207514 DOI: 10.2337/db15-1627] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 04/09/2016] [Indexed: 11/13/2022]
Abstract
Mineralocorticoid receptor (MR) expression is increased in adipose tissue from obese individuals and animals. We previously demonstrated that adipocyte-MR overexpression (Adipo-MROE) in mice is associated with metabolic changes. Whether adipocyte MR directly influences vascular function in these mice is unknown. We tested this hypothesis in resistant mesenteric arteries from Adipo-MROE mice using myography and in cultured adipocytes. Molecular mechanisms were probed in vessels/vascular smooth muscle cells and adipose tissue/adipocytes and focused on redox-sensitive pathways, Rho kinase activity, and protein kinase G type-1 (PKG-1) signaling. Adipo-MROE versus control-MR mice exhibited reduced vascular contractility, associated with increased generation of adipocyte-derived hydrogen peroxide, activation of vascular redox-sensitive PKG-1, and downregulation of Rho kinase activity. Associated with these vascular changes was increased elastin content in Adipo-MROE. Inhibition of PKG-1 with Rp-8-Br-PET-cGMPS normalized vascular contractility in Adipo-MROE. In the presence of adipocyte-conditioned culture medium, anticontractile effects of the adipose tissue were lost in Adipo-MROE mice but not in control-MR mice. In conclusion, adipocyte-MR upregulation leads to impaired contractility with preserved endothelial function and normal blood pressure. Increased elasticity may contribute to hypocontractility. We also identify functional cross talk between adipocyte MR and arteries and describe novel mechanisms involving redox-sensitive PKG-1 and Rho kinase. Our results suggest that adipose tissue from Adipo-MROE secrete vasoactive factors that preferentially influence vascular smooth muscle cells rather than endothelial cells. Our findings may be important in obesity/adiposity where adipocyte-MR expression/signaling is amplified and vascular risk increased.
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Affiliation(s)
- Aurelie Nguyen Dinh Cat
- Cardiovascular Research and Medical Sciences Institute, University of Glasgow, Glasgow, U.K.
| | - Tayze T Antunes
- Kidney Research Centre, Ottawa Hospital Research Institute, University of Ottawa, Ottawa, Ontario, Canada
| | - Glaucia E Callera
- Kidney Research Centre, Ottawa Hospital Research Institute, University of Ottawa, Ottawa, Ontario, Canada
| | - Ana Sanchez
- Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| | - Sofia Tsiropoulou
- Cardiovascular Research and Medical Sciences Institute, University of Glasgow, Glasgow, U.K
| | - Maria G Dulak-Lis
- Cardiovascular Research and Medical Sciences Institute, University of Glasgow, Glasgow, U.K
| | | | - Ying He
- Kidney Research Centre, Ottawa Hospital Research Institute, University of Ottawa, Ottawa, Ontario, Canada
| | - Augusto C Montezano
- Cardiovascular Research and Medical Sciences Institute, University of Glasgow, Glasgow, U.K
| | - Frederic Jaisser
- INSERM Unit 1138 Team 1, Centre de Recherche des Cordeliers, University Pierre and Marie Curie, Paris, France INSERM, Clinical Investigation Centre 1430, APHP, Henri Mondor Hospital, Pole VERDI, Paris East University, Creteil, France
| | - Rhian M Touyz
- Cardiovascular Research and Medical Sciences Institute, University of Glasgow, Glasgow, U.K. Kidney Research Centre, Ottawa Hospital Research Institute, University of Ottawa, Ottawa, Ontario, Canada
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Tsiropoulou S, Montezano AC, Scott A, Burchmore RJ, Touyz RM. 41 Vascular protein oxidation and redox proteomics in human hypertension. Heart 2015. [DOI: 10.1136/heartjnl-2015-308734.41] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Tsiropoulou S, Montezano AC, Scott A, Burchmore RJ, Touyz RM. Abstract P096: Vascular Protein Oxidation and Redox Proteomics in Human Hypertension. Hypertension 2015. [DOI: 10.1161/hyp.66.suppl_1.p096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Oxidative stress has been implicated in the pathophysiology of hypertension (HTN) through redox-sensitive processes that cause vascular damage. Despite recent advances in the field of vascular redox signalling in HTN, it still remains unclear exactly how ROS cause vascular injury. We hypothesise that regulation of redox-sensitive protein tyrosine phosphatases (PTP) through post-translational oxidative modification, is impaired in HTN where ROS levels are increased. Vascular smooth muscle cells (VSMC) from small arteries of normotensive (NT) and hypertensive (HT) individuals were stimulated with AngII (10-7 M) and ET-1 (10-7 M). Irreversible oxidation of proteins and PTPs was assessed by oxyblot and immunoblotting, respectively. Differential gel electrophoresis (DiGE) and CyDye thiol labelling were employed for screening of reversibly oxidised proteome. Irreversible protein oxidation was not affected by AngII or ET-1 in VSMCs from NT and HT subjects. PTP hyperoxidation tended to increase in VSMCs from NT upon stimulation with AngII (FC=2.12 at 60min) and ET-1 (FC=1.60 at 60min), whereas a similar trend was observed only after AngII treatment (FC=1.38 at 60min) in HTN (p>0.05). Proteomic data, filtered for FC>2, detected 2051 spots with 1899 (92.5%) being equally oxidised between NT and HT. In addition, oxidation of 57 (2.9%) spots was increased, while 95 (4.6%) were decreased in HT. Candidate proteins exhibiting consistent changes across three experimental replicates included β-actin (FC=-2.86), annexin A1 (-2.23), galectin-1 (-1.67), FK506 binding protein (-2.35) and polymerase I and transcript release factor (PTRF, -1.92). Stimulation with AngII altered the redox status in 2-3% of proteins, both in HT and NT. However, vimentin was the only target changing consistently across the replicates (FC=2.48). Our findings indicate that pro-hypertensive agents may not impact significantly on irreversible protein and PTP oxidation in health and disease, but may have effects on reversible oxidation. Our proteomic data, in agreement with our previous rat studies, support decreased reversible thiol oxidation in HTN. Moreover, these novel findings identify differentially oxidised proteins which may contribute to oxidative vascular injury in HTN.
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Affiliation(s)
| | | | - Alan Scott
- Univ of Glasgow, Glasgow, United Kingdom
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Montezano AC, Dulak-Lis M, Tsiropoulou S, Harvey A, Briones AM, Touyz RM. Oxidative Stress and Human Hypertension: Vascular Mechanisms, Biomarkers, and Novel Therapies. Can J Cardiol 2015; 31:631-41. [DOI: 10.1016/j.cjca.2015.02.008] [Citation(s) in RCA: 205] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 02/06/2015] [Accepted: 02/06/2015] [Indexed: 02/07/2023] Open
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Tsiropoulou S, Montezano AC, Scott A, Burchmore RJ, Touyz RM. Abstract 280: Protein Tyrosine Phosphatase Oxidation and Redox Proteomics in Hypertension. Hypertension 2014. [DOI: 10.1161/hyp.64.suppl_1.280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Aberrant signalling and vascular dysfunction in hypertension (HTN) have been associated with reactive oxygen species (ROS)-induced oxidation of redox-sensitive molecules. Protein tyrosine phosphatases (PTP) are susceptible to oxidation of thiols (-SH) at their active site, which leads to PTP inactivation. We hypothesize that oxidative stress is associated with reversible PTP oxidation and consequent reduced PTP activation in HTN. VSMCs from normotensive and hypertensive rats (WKY and SHRSP) were stimulated with AngII (10-7 M) and ET-1 (10-7 M). Protein oxidation was assessed by the oxyblot assay. PTP oxidation, TC-PTP and PTP1B expression levels were assessed by immunoblotting. Differential gel electrophoresis (DiGE) of CyDye-labelled cell lysates was employed for screening of oxidized proteome. Global-protein and PTP-specific oxidation was increased in VSMCs from SHRSP versus WKY (fold change (FC)=1.29 and FC=1.53, p<0.05, respectively). AngII stimulation did not affect global oxidation in either WKY or SHRSP, but increased PTP-oxidation in WKY (FC=1.47 at 5min, p<0.05) to levels similar to SHRSP. Stimulation with ET-1 increased total oxidation only in WKY (FC=1.52 at 15min, p<0.05) but not SHRSP, and had no effects on PTPs oxidation. Moreover, stimulation with AngII and ET-1 reduced protein expression of TC-PTP (FCAngII=0.8 at 2h for WKY; FCAngII=0.9 at 1h for SHRSP; FCET1=0.8 at 2h for WKY and 1h for SHRSP) and PTPB1 (FCAngII=0.87 at 1h for WKY and SHRSP; FCET1=0.9 at 2h for WKY and SHRSP), (p<0.05). DiGE proteomic data, filtered for FC>2, detected 1777 spots of which 1388 (78.1%) were equally oxidized across SHRSP and WKY, and 264 (14.9%) exhibited increased oxidation levels in SHRSP. Our findings demonstrate that oxidation of PTPs is increased in VSMCs from hypertensive rats and that vasoactive agents differentially regulate PTP oxidation and their expression levels in HTN. Furthermore, the oxidized state of 21.9% of the global proteome is altered in disease. Ongoing studies, in both rats and humans, are focusing on the characterization of a PTP-oxidation signature in HTN. Identification of specific PTPs which are deregulated in HTN could elucidate aberrant redox signalling in vascular dysfunction and highlight novel therapeutic targets.
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Affiliation(s)
| | | | - Alan Scott
- Univ of Glasgow, Glasgow, United Kingdom
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