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Fuggetta N, Rigolli N, Magdeleine M, Seminara A, Drin G. Reconstitution of ORP-mediated lipid exchange process coupled to PI(4)P metabolism. bioRxiv 2023:2023.08.04.551917. [PMID: 37577629 PMCID: PMC10418177 DOI: 10.1101/2023.08.04.551917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Lipid distribution in the eukaryotic cells depends on tight couplings between lipid transfer and lipid metabolism. Yet these couplings remain poorly described. Notably, it is unclear to what extent lipid exchangers of the OSBP-related proteins (ORPs) family, coupled to PI(4)P metabolism, contribute to the formation of sterol and phosphatidylserine gradient between the endoplasmic reticulum (ER) and other cell regions. To address this question, we have examined in vitro the activity of Osh4p, a representative ORP, between Golgi mimetic membranes in which PI(4)P is produced by a PI 4-kinase and ER mimetic membranes in which PI(4)P is hydrolyzed by the phosphatase Sac1p. Using quantitative, real-time assays, we demonstrate that Osh4p creates a sterol gradient between the two membranes by sterol/PI(4)P exchange as soon as a PI(4)P gradient is generated at this interface following ATP addition, and define how much PI(4)P must be synthesized for this process. Then, using a kinetic model supported by our in vitro data, we estimate to what extent PI(4)P metabolism can drive lipid transfer in cells. Finally, we show that Sec14p, by transferring phosphatidylinositol between membranes, can support the synthesis of PI(4)P and the creation of a sterol gradient by Osh4p. These results indicate to what extent ORPs, under the control of PI(4)P metabolism, can distribute lipids in the cell.
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Affiliation(s)
- Nicolas Fuggetta
- Université Côte d'Azur, Centre National de la Recherche Scientifique, Institut de Pharmacologie Moléculaire et Cellulaire, 660 route des lucioles, 06560 Valbonne, France
| | - Nicola Rigolli
- Laboratoire de Physique, École Normale Supérieure (LPENS), 75005 Paris, France
| | - Maud Magdeleine
- Université Côte d'Azur, Centre National de la Recherche Scientifique, Institut de Pharmacologie Moléculaire et Cellulaire, 660 route des lucioles, 06560 Valbonne, France
| | - Agnese Seminara
- Malga, Department of Civil, Chemical and Environmental Engineering, University of Genoa, Villa Cambiaso 1, 16145 Genoa, Italy
| | - Guillaume Drin
- Université Côte d'Azur, Centre National de la Recherche Scientifique, Institut de Pharmacologie Moléculaire et Cellulaire, 660 route des lucioles, 06560 Valbonne, France
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Cai S, Wu Y, Guillén-Samander A, Hancock-Cerutti W, Liu J, De Camilli P. In situ architecture of the lipid transport protein VPS13C at ER-lysosome membrane contacts. Proc Natl Acad Sci U S A 2022; 119:e2203769119. [PMID: 35858323 DOI: 10.1073/pnas.2203769119] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
VPS13 is a eukaryotic lipid transport protein localized at membrane contact sites. Previous studies suggested that it may transfer lipids between adjacent bilayers by a bridge-like mechanism. Direct evidence for this hypothesis from a full-length structure and from electron microscopy (EM) studies in situ is still missing, however. Here, we have capitalized on AlphaFold predictions to complement the structural information already available about VPS13 and to generate a full-length model of human VPS13C, the Parkinson's disease-linked VPS13 paralog localized at contacts between the endoplasmic reticulum (ER) and endo/lysosomes. Such a model predicts an ∼30-nm rod with a hydrophobic groove that extends throughout its length. We further investigated whether such a structure can be observed in situ at ER-endo/lysosome contacts. To this aim, we combined genetic approaches with cryo-focused ion beam (cryo-FIB) milling and cryo-electron tomography (cryo-ET) to examine HeLa cells overexpressing this protein (either full length or with an internal truncation) along with VAP, its anchoring binding partner at the ER. Using these methods, we identified rod-like densities that span the space separating the two adjacent membranes and that match the predicted structures of either full-length VPS13C or its shorter truncated mutant, thus providing in situ evidence for a bridge model of VPS13 in lipid transport.
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Popp J, Trendelenburg V, Niggemann B, Randow S, Völker E, Vogel L, Reuter A, Spiric J, Schiller D, Beyer K, Holzhauser T. Pea (Pisum sativum) allergy in children: Pis s 1 is an immunodominant major pea allergen and presents IgE binding sites with potential diagnostic value. Clin Exp Allergy 2020; 50:625-635. [PMID: 32078204 DOI: 10.1111/cea.13590] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 02/07/2020] [Accepted: 02/15/2020] [Indexed: 11/27/2022]
Abstract
BACKGROUND Food allergy to pea (Pisum sativum) has been rarely studied in children at the clinical and molecular levels. OBJECTIVE To elucidate the allergenic relevance and diagnostic value of pea 7S globulin Pis s 1, nsLTP, and 2S albumins PA1 and PA2 in children. METHODS Children with pea-specific IgE ≥ 0.35 kUA /L and clinical evidence of pea allergy or tolerance were included in the study. IgE binding against pea total protein extract, recombinant (r) rPis s 1, rPA1, rPA2, and natural nsLTP was analysed using IgE immunoblot/inhibition. Mediator release potency was investigated in passively sensitized rat basophil leukaemia (RBL) 2H3-cells. IgE binding to synthetic overlapping peptides of Pis s 1 was detected on multipeptide microarrays. RESULTS 19 pea-sensitized children were included, 14 with doctors' diagnosed allergy and 5 with tolerance to pea (median age 3.5 and 4.5 years, respectively). 11/14 (78%) pea-allergic and 1/5 (20%) tolerant children were sensitized to Pis s 1. Under the reducing conditions of immunoblot analysis, IgE binding to rPA1 was negligible, sensitization to rPA2 and nsLTP undetectable. Compared to pea total protein extract, rPis s 1 displayed on average 58% IgE binding capacity and a 20-fold higher mediator release potency. Selected Pis s 1-related peptides displayed IgE binding in pea-allergic but not in pea-tolerant children. CONCLUSIONS AND CLINICAL RELEVANCE In this study group, Pis s 1 is a major immunodominant allergen in pea-allergic children. Evidence for sensitization to nsLTP and 2S albumins was low but requires further verification with regard to conformational epitopes. Recombinant Pis s 1 and related peptides which were exclusively recognized by pea-allergic children may improve in vitro diagnosis of pea allergy once verified in prospective studies with larger study groups.
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Affiliation(s)
- Jasmin Popp
- Division of Allergology, Paul-Ehrlich-Institut, Langen, Germany
| | - Valérie Trendelenburg
- Department of Pediatric Pulmonology, Immunology and Intensive Care Medicine, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Bodo Niggemann
- Department of Pediatric Pulmonology, Immunology and Intensive Care Medicine, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Stefanie Randow
- Division of Allergology, Paul-Ehrlich-Institut, Langen, Germany
| | - Elke Völker
- Division of Allergology, Paul-Ehrlich-Institut, Langen, Germany
| | - Lothar Vogel
- Division of Allergology, Paul-Ehrlich-Institut, Langen, Germany
| | - Andreas Reuter
- Division of Allergology, Paul-Ehrlich-Institut, Langen, Germany
| | - Jelena Spiric
- Division of Allergology, Paul-Ehrlich-Institut, Langen, Germany
| | - Dirk Schiller
- Division of Allergology, Paul-Ehrlich-Institut, Langen, Germany
| | - Kirsten Beyer
- Department of Pediatric Pulmonology, Immunology and Intensive Care Medicine, Charité Universitätsmedizin Berlin, Berlin, Germany
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Péresse T, Kovacs D, Subra M, Bigay J, Tsai MC, Polidori J, Gautier R, Desrat S, Fleuriot L, Debayle D, Litaudon M, Pham VC, Bignon J, Antonny B, Roussi F, Mesmin B. Molecular and cellular dissection of the oxysterol-binding protein cycle through a fluorescent inhibitor. J Biol Chem 2020; 295:4277-4288. [PMID: 32075908 PMCID: PMC7105299 DOI: 10.1074/jbc.ra119.012012] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [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: 11/21/2019] [Revised: 02/09/2020] [Indexed: 01/02/2023] Open
Abstract
ORPphilins are bioactive natural products that strongly and selectively inhibit the growth of some cancer cell lines and are proposed to target intracellular lipid-transfer proteins of the oxysterol-binding protein (OSBP) family. These conserved proteins exchange key lipids, such as cholesterol and phosphatidylinositol 4-phosphate (PI(4)P), between organelle membranes. Among ORPphilins, molecules of the schweinfurthin family interfere with intracellular lipid distribution and metabolism, but their functioning at the molecular level is poorly understood. We report here that cell line sensitivity to schweinfurthin G (SWG) is inversely proportional to cellular OSBP levels. By taking advantage of the intrinsic fluorescence of SWG, we followed its fate in cell cultures and show that its incorporation at the trans-Golgi network depends on cellular abundance of OSBP. Using in vitro membrane reconstitution systems and cellular imaging approaches, we also report that SWG inhibits specifically the lipid transfer activity of OSBP. As a consequence, post-Golgi trafficking, membrane cholesterol levels, and PI(4)P turnover were affected. Finally, using intermolecular FRET analysis, we demonstrate that SWG directly binds to the lipid-binding cavity of OSBP. Collectively these results describe SWG as a specific and intrinsically fluorescent pharmacological tool for dissecting OSBP properties at the cellular and molecular levels. Our findings indicate that SWG binds OSBP with nanomolar affinity, that this binding is sensitive to the membrane environment, and that SWG inhibits the OSBP-catalyzed lipid exchange cycle.
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Affiliation(s)
- Tiphaine Péresse
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris-Saclay, Gif-sur-Yvette, France
| | - David Kovacs
- Université Côte d'Azur, Inserm, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne, France
| | - Mélody Subra
- Université Côte d'Azur, Inserm, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne, France
| | - Joëlle Bigay
- Université Côte d'Azur, Inserm, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne, France
| | - Meng-Chen Tsai
- Université Côte d'Azur, Inserm, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne, France
| | - Joël Polidori
- Université Côte d'Azur, Inserm, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne, France
| | - Romain Gautier
- Université Côte d'Azur, Inserm, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne, France
| | - Sandy Desrat
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Lucile Fleuriot
- Université Côte d'Azur, Inserm, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne, France
| | - Delphine Debayle
- Université Côte d'Azur, Inserm, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne, France
| | - Marc Litaudon
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Van-Cuong Pham
- Advanced Center for Bioorganic Chemistry of the Institute of Marine Biochemistry, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, 8404, Caugiay, Hanoi, Vietnam
| | - Jérôme Bignon
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Bruno Antonny
- Université Côte d'Azur, Inserm, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne, France
| | - Fanny Roussi
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris-Saclay, Gif-sur-Yvette, France.
| | - Bruno Mesmin
- Université Côte d'Azur, Inserm, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne, France.
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Guillén-Samander A, Bian X, De Camilli P. PDZD8 mediates a Rab7-dependent interaction of the ER with late endosomes and lysosomes. Proc Natl Acad Sci U S A 2019; 116:22619-23. [PMID: 31636202 DOI: 10.1073/pnas.1913509116] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Contacts between the endoplasmic reticulum (ER) and other membranes are hot spots for protein-mediated lipid transport between the 2 adjacent bilayers. Compiling a molecular inventory of lipid transport proteins present at these sites is a premise to the elucidation of their function. Here we show that PDZD8, an intrinsic membrane protein of the ER with a lipid transport module of the SMP domain family, concentrates at contacts between the ER and late endosomes/lysosomes, where it interacts with GTP-Rab7. These findings suggest that PDZD8 may cooperate with other proteins that function at the ER-endo/lysosome interface in coordinating endocytic flow with lipid transport between endocytic membranes and the ER.
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Kumagai K, Hanada K. Structure, functions and regulation of CERT, a lipid-transfer protein for the delivery of ceramide at the ER-Golgi membrane contact sites. FEBS Lett 2019; 593:2366-2377. [PMID: 31254361 DOI: 10.1002/1873-3468.13511] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [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: 05/17/2019] [Revised: 06/26/2019] [Accepted: 06/26/2019] [Indexed: 12/17/2022]
Abstract
The inter-organelle transport of lipids must be regulated to ensure appropriate lipid composition of each organelle. In mammalian cells, ceramide synthesised in the endoplasmic reticulum (ER) is transported to the trans-Golgi regions, where ceramide is converted to sphingomyelin (SM) with the concomitant production of diacylglycerol. Ceramide transport protein (CERT) transports ceramide from the ER to the trans-Golgi regions at the ER-Golgi membrane contact sites (MCS). The function of CERT is down-regulated by multisite phosphorylation of a serine-repeat motif (SRM) and up-regulated by phosphorylation of serine 315 in CERT. Multisite phosphorylation of the SRM is primed by protein kinase D, which is activated by diacylglycerol. The function of CERT is regulated by a phosphorylation-dependent feedback mechanism in response to cellular requirements of SM. CERT-dependent ceramide transport is also affected by the pool of phosphatidylinositol (PtdIns)-4-phosphate (PtdIns(4)P) in the trans-Golgi regions, while the PtdIns(4)P pool is regulated by PtdIns-4-kinases and oxysterol-binding protein. The ER-Golgi MCS may serve as inter-organelle communication zones, in which many factors work in concert to serve as an extensive rheostat of SM, diacylglycerol, cholesterol and PtdIns(4)P.
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Affiliation(s)
- Keigo Kumagai
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Kentaro Hanada
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Tokyo, Japan
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Sun EW, Guillén-Samander A, Bian X, Wu Y, Cai Y, Messa M, De Camilli P. Lipid transporter TMEM24/C2CD2L is a Ca 2+-regulated component of ER-plasma membrane contacts in mammalian neurons. Proc Natl Acad Sci U S A 2019; 116:5775-84. [PMID: 30819882 DOI: 10.1073/pnas.1820156116] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Close appositions between the endoplasmic reticulum (ER) and the plasma membrane (PM) are a general feature of all cells and are abundant in neurons. A function of these appositions is lipid transport between the two adjacent bilayers via tethering proteins that also contain lipid transport modules. However, little is known about the properties and dynamics of these proteins in neurons. Here we focused on TMEM24/C2CD2L, an ER-localized SMP domain containing phospholipid transporter expressed at high levels in the brain, previously shown to be a component of ER-PM contacts in pancreatic β-cells. TMEM24 is enriched in neurons versus glial cells and its levels increase in parallel with neuronal differentiation. It populates ER-PM contacts in resting neurons, but elevations of cytosolic Ca2+ mediated by experimental manipulations or spontaneous activity induce its transient redistribution throughout the entire ER. Dissociation of TMEM24 from the plasma membrane is mediated by phosphorylation of an array of sites in the C-terminal region of the protein. These sites are only partially conserved in C2CD2, the paralogue of TMEM24 primarily expressed in nonneuronal tissues, which correspondingly display a much lower sensitivity to Ca2+ elevations. ER-PM contacts in neurons are also sites where Kv2 (the major delayed rectifier K+ channels in brain) and other PM and ER ion channels are concentrated, raising the possibility of a regulatory feedback mechanism between neuronal excitability and lipid exchange between the ER and the PM.
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Pries V, Nöcker C, Khan D, Johnen P, Hong Z, Tripathi A, Keller AL, Fitz M, Perruccio F, Filipuzzi I, Thavam S, Aust T, Riedl R, Ziegler S, Bono F, Schaaf G, Bankaitis VA, Waldmann H, Hoepfner D. Target Identification and Mechanism of Action of Picolinamide and Benzamide Chemotypes with Antifungal Properties. Cell Chem Biol 2018; 25:279-290.e7. [PMID: 29307839 DOI: 10.1016/j.chembiol.2017.12.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 10/18/2017] [Accepted: 12/06/2017] [Indexed: 11/20/2022]
Abstract
Invasive fungal infections are accompanied by high mortality rates that range up to 90%. At present, only three different compound classes are available for use in the clinic, and these often suffer from low bioavailability, toxicity, and drug resistance. These issues emphasize an urgent need for novel antifungal agents. Herein, we report the identification of chemically versatile benzamide and picolinamide scaffolds with antifungal properties. Chemogenomic profiling and biochemical assays with purified protein identified Sec14p, the major phosphatidylinositol/phosphatidylcholine transfer protein in Saccharomyces cerevisiae, as the sole essential target for these compounds. A functional variomics screen identified resistance-conferring residues that localized to the lipid-binding pocket of Sec14p. Determination of the X-ray co-crystal structure of a Sec14p-compound complex confirmed binding in this cavity and rationalized both the resistance-conferring residues and the observed structure-activity relationships. Taken together, these findings open new avenues for rational compound optimization and development of novel antifungal agents.
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Hill CH, Read RJ, Deane JE. Structure of human saposin A at lysosomal pH. Acta Crystallogr F Struct Biol Commun 2015; 71:895-900. [PMID: 26144235 PMCID: PMC4498711 DOI: 10.1107/s2053230x15008584] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 05/01/2015] [Indexed: 11/10/2022]
Abstract
The saposins are essential cofactors for the normal lysosomal degradation of complex glycosphingolipids by acid hydrolase enzymes; defects in either saposin or hydrolase function lead to severe metabolic diseases. Saposin A (SapA) activates the enzyme β-galactocerebrosidase (GALC), which catalyzes the breakdown of β-D-galactocerebroside, the principal lipid component of myelin. SapA is known to bind lipids and detergents in a pH-dependent manner; this is accompanied by a striking transition from a `closed' to an `open' conformation. However, previous structures were determined at non-lysosomal pH. This work describes a 1.8 Å resolution X-ray crystal structure determined at the physiologically relevant lysosomal pH 4.8. In the absence of lipid or detergent at pH 4.8, SapA is observeed to adopt a conformation closely resembling the previously determined `closed' conformation, showing that pH alone is not sufficient for the transition to the `open' conformation. Structural alignments reveal small conformational changes, highlighting regions of flexibility.
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Affiliation(s)
- Chris H Hill
- Department of Haematology, Cambridge Institute for Medical Research, University of Cambridge, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, England
| | - Randy J Read
- Department of Haematology, Cambridge Institute for Medical Research, University of Cambridge, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, England
| | - Janet E Deane
- Department of Haematology, Cambridge Institute for Medical Research, University of Cambridge, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, England
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Weinhold A, Wielsch N, Svatoš A, Baldwin IT. Label-free nanoUPLC-MSE based quantification of antimicrobial peptides from the leaf apoplast of Nicotiana attenuata. BMC Plant Biol 2015; 15:18. [PMID: 25604123 PMCID: PMC4318441 DOI: 10.1186/s12870-014-0398-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 12/22/2014] [Indexed: 05/30/2023]
Abstract
BACKGROUND Overexpressing novel antimicrobial peptides (AMPs) in plants is a promising approach for crop disease resistance engineering. However, the in planta stability and subcellular localization of each AMP should be validated for the respective plant species, which can be challenging due to the small sizes and extreme pI ranges of AMPs which limits the utility of standard proteomic gel-based methods. Despite recent advances in quantitative shotgun proteomics, its potential for AMP analysis has not been utilized and high throughput methods are still lacking. RESULTS We created transgenic Nicotiana attenuata plants that independently express 10 different AMPs under a constitutive 35S promoter and compared the extracellular accumulation of each AMP using a universal and versatile protein quantification method. We coupled a rapid apoplastic peptide extraction with label-free protein quantification by nanoUPLC-MSE analysis using Hi3 method and identified/quantified 7 of 10 expressed AMPs in the transgenic plants ranging from 37 to 91 amino acids in length. The quantitative comparison among the transgenic plant lines showed that three particular peptides, belonging to the defensin, knottin and lipid-transfer protein families, attained the highest concentrations of 91 to 254 pmol per g leaf fresh mass, which identified them as best suited for ectopic expression in N. attenuata. The chosen mass spectrometric approach proved to be highly sensitive in the detection of different AMP types and exhibited the high level of analytical reproducibility required for label-free quantitative measurements along with a simple protocol required for the sample preparation. CONCLUSIONS Heterologous expression of AMPs in plants can result in highly variable and non-predictable peptide amounts and we present a universal quantitative method to confirm peptide stability and extracellular deposition. The method allows for the rapid quantification of apoplastic peptides without cumbersome and time-consuming purification or chromatographic steps and can be easily adapted to other plant species.
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Affiliation(s)
- Arne Weinhold
- />Max Planck Institute for Chemical Ecology, Department of Molecular Ecology, Hans-Knöll-Straße 8, 07745 Jena, Germany
| | - Natalie Wielsch
- />Max Planck Institute for Chemical Ecology, Mass Spectrometry/Proteomics Research Group, Hans-Knöll-Straße 8, 07745 Jena, Germany
| | - Aleš Svatoš
- />Max Planck Institute for Chemical Ecology, Mass Spectrometry/Proteomics Research Group, Hans-Knöll-Straße 8, 07745 Jena, Germany
| | - Ian T Baldwin
- />Max Planck Institute for Chemical Ecology, Department of Molecular Ecology, Hans-Knöll-Straße 8, 07745 Jena, Germany
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Mayorga C, Gomez F, Aranda A, Koppelman SJ, Diaz-Perales A, Blanca-López N, Blazquez AB, Blanca M, Torres MJ. Basophil response to peanut allergens in Mediterranean peanut-allergic patients. Allergy 2014; 69:964-8. [PMID: 24816395 DOI: 10.1111/all.12421] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/29/2014] [Indexed: 11/30/2022]
Abstract
Ara h 1, Ara h 2, and Ara h 3 are important sensitizers in peanut allergy. Ara h 9 has also been shown to be relevant in the Mediterranean area. We evaluated the basophil response to peanut allergens and Pru p 3 in Mediterranean patients: Group 1, peanut and peach allergy; Group 2, peanut allergy and tolerance to peach; Group 3, peach allergy and tolerance to peanut; Group 4, nonallergic subjects that tolerate both peanut and peach. Compared to controls (Group 4), there was an increased basophil activation with Ara h 2 (P = 0.031) and Pru p 3 (P = 0.009) in Group 1 and with Ara h 1 (P = 0.016), Ara h 2 (P = 0.001), and Ara h 9 (P = 0.016) in Group 2. Importantly, only Ara h 2 showed an increased activation (P = 0.009) in Group 2 compared to Group 3. Ara h 2 is the best discriminating allergen for peanut allergy diagnosis in a Mediterranean population showing two patterns: patients also allergic to peach, responding to Ara h 2 and Pru p 3, and patients allergic only to peanut, responding to Ara h 1, Ara h 2, and Ara h 9.
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Affiliation(s)
- C. Mayorga
- Research Laboratory; IBIMA; Regional University Hospital of Malaga; UMA; Malaga Spain
- UGC Allergy; IBIMA; Regional University Hospital of Malaga; UMA; Malaga Spain
| | - F. Gomez
- UGC Allergy; IBIMA; Regional University Hospital of Malaga; UMA; Malaga Spain
| | - A. Aranda
- Research Laboratory; IBIMA; Regional University Hospital of Malaga; UMA; Malaga Spain
| | - S. J. Koppelman
- University of Nebraska; Lincoln NE USA
- HAL Allergy; Leiden the Netherlands
| | - A. Diaz-Perales
- Centre for Plant Biotechnology and Genomics UPM-INIA; Pozuelo de Alarcón; Madrid Spain
| | | | - A. B. Blazquez
- Research Laboratory; IBIMA; Regional University Hospital of Malaga; UMA; Malaga Spain
| | - M. Blanca
- UGC Allergy; IBIMA; Regional University Hospital of Malaga; UMA; Malaga Spain
| | - M. J. Torres
- UGC Allergy; IBIMA; Regional University Hospital of Malaga; UMA; Malaga Spain
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