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Lan WH, He H, Bayley H, Qing Y. Location of Phosphorylation Sites within Long Polypeptide Chains by Binder-Assisted Nanopore Detection. J Am Chem Soc 2024; 146:24265-24270. [PMID: 38986019 PMCID: PMC11378271 DOI: 10.1021/jacs.4c03912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/12/2024]
Abstract
The detection and mapping of protein phosphorylation sites are essential for understanding the mechanisms of various cellular processes and for identifying targets for drug development. The study of biopolymers at the single-molecule level has been revolutionized by nanopore technology. In this study, we detect protein phosphorylation within long polypeptides (>700 amino acids), after the attachment of binders that interact with phosphate monoesters; electro-osmosis is used to drive the tagged chains through engineered protein nanopores. By monitoring the ionic current carried by a nanopore, phosphorylation sites are located within individual polypeptide chains, providing a valuable step toward nanopore proteomics.
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Affiliation(s)
- Wei-Hsuan Lan
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
| | - Hanxiao He
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
| | - Hagan Bayley
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
| | - Yujia Qing
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
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Matsumura F, Murayama T, Kuriyama R, Matsumura A, Yamashiro S. Myosin phosphatase targeting subunit1 controls localization and motility of Rab7-containing vesicles: Is myosin phosphatase a cytoplasmic dynein regulator? Cytoskeleton (Hoboken) 2024. [PMID: 38700016 DOI: 10.1002/cm.21871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 04/11/2024] [Accepted: 04/12/2024] [Indexed: 05/05/2024]
Abstract
Myosin phosphatase targeting subunit1 (MYPT1) is a critical subunit of myosin phosphatase (MP), which brings PP1Cδ phosphatase and its substrate together. We previously showed that MYPT1 depletion resulted in oblique chromatid segregation. Therefore, we hypothesized that MYPT1 may control microtubule-dependent motor activity. Dynein, a minus-end microtubule motor, is known to be involved in mitotic spindle assembly. We thus examined whether MYPT1 and dynein may interact. Proximity ligation assay and co-immunoprecipitation revealed that MYPT1 and dynein intermediate chain (DIC) were associated. We found that DIC phosphorylation is increased in MYPT1-depleted cells in vivo, and that MP was able to dephosphorylate DIC in vitro. MYPT1 depletion also altered the localization and motility of Rab7-containing vesicles. MYPT1-depletion dispersed the perinuclear Rab7 localization to the peripheral in interphase cells. The dispersed Rab7 localization was rescued by microinjection of a constitutively active, truncated MYPT1 mutant, supporting that MP is responsible for the altered Rab7 localization. Analyses of Rab7 vesicle trafficking also revealed that minus-end transport was reduced in MYPT1-depleted cells. These results suggest an unexpected role of MP: MP controls dynein activity in both mitotic and interphase cells, possibly by dephosphorylating dynein subunits including DIC.
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Affiliation(s)
- Fumio Matsumura
- Department of Molecular Biology & Biochemistry, Rutgers University, Piscataway, New Jersey, USA
| | - Takashi Murayama
- Department of Pharmacology, Juntendo University School of Medicine, Tokyo, Japan
| | - Ryoko Kuriyama
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, Minnesota, USA
| | - Aya Matsumura
- Department of Molecular Biology & Biochemistry, Rutgers University, Piscataway, New Jersey, USA
| | - Shigeko Yamashiro
- Department of Molecular Biology & Biochemistry, Rutgers University, Piscataway, New Jersey, USA
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Hirano H, Shirakawa J. Recent developments in Phos-tag electrophoresis for the analysis of phosphoproteins in proteomics. Expert Rev Proteomics 2022; 19:103-114. [PMID: 35285370 DOI: 10.1080/14789450.2022.2052850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
INTRODUCTION Phosphate-binding tag (Phos-tag) sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) is an important development capable of analyzing the phosphorylation state of proteins. Conventionally, proteins were separated via SDS-PAGE and Phos-tag SDS-PAGE that use different gels to identify phosphorylated proteins. However, it was often difficult to compare the electrophoretic mobility of the proteins in the different gels used. The recently developed Phos-tag diagonal electrophoresis has been able to solve this problem. It can indicate the SDS-PAGE and Phos-tag SDS-PAGE patterns on a single gel; therefore, phosphorylated proteins can be distinguished easily from non-phosphorylated proteins. AREAS COVERED This review assesses the importance of Phos-tag electrophoresis, which enables the analysis of protein phosphorylation states, in the field of proteomics. Additionally, this review describes the significance and actual experimental technique of Phos-tag diagonal electrophoresis, which was recently developed to overcome the drawbacks of Phos-tag SDS-PAGE. EXPERT OPINION Although shotgun analysis of proteins allows detecting many phosphorylation sites, it is challenging to clarify the differences in the phosphorylation states of protein molecules using this technique. Therefore, Phos-tag SDS-PAGE is frequently used to determine the phosphorylation state of proteins. This technique has become more powerful with the recent development of Phos-tag diagonal electrophoresis.
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Affiliation(s)
- Hisashi Hirano
- Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Gunma, Japan
| | - Jun Shirakawa
- Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Gunma, Japan
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Kinoshita E, Kinoshita-Kikuta E, Koike T. History of Phos-tag technology for phosphoproteomics. J Proteomics 2022; 252:104432. [PMID: 34818585 DOI: 10.1016/j.jprot.2021.104432] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 11/06/2021] [Accepted: 11/15/2021] [Indexed: 12/14/2022]
Abstract
Phos-tag is a functional molecule that selectively captures a phosphate monoester dianion in neutral aqueous solutions. The affinity of Phos-tag for phosphate monoester dianions is more than 10,000 times greater than that for other anions present in living organisms, such as carboxylic acid anions. We have developed and applied useful techniques for phosphoproteomics based on Phos-tag. This review describes the history of Phos-tag development and outlines three main technologies that have been put to practical use. The first is a technique to separate and concentrate phosphopeptides and phosphoproteins using a Phos-tag derivative with a hydrophilic chromatography carrier (Phos-tag polymer beads). The second is a technology to detect phosphopeptides and phosphoproteins on various arrays using Phos-tag biotin. The third is a technique to separate and detect phosphoproteins by electrophoresis using Phos-tag acrylamide. We hope that these three technologies will make a significant contribution to phosphoproteomics and, ultimately, to life science research. SIGNIFICANCE: The authors found that a dinuclear metal complex of 1,3-bis[bis(pyridin-2-ylmethyl)-amino]propan-2-olato acted as a novel phosphate-binding tag nanomolecule, Phos-tag, in an aqueous solution under near physiological conditions. The metal complex having a vacancy on two metal ions is suitable for the access of a phosphomonoester dianion (R-OPO32-) as a bridging ligand. A dinuclear zinc(II) complex (Zn2+-Phos-tag) strongly binds to a p-nitrophenyl phosphate dianion (Kd = 2.5 × 10-8 M) at a neutral pH. The anion selectivity indexes against SO42-, CH3COO-, Cl-, and the bisphenyl phosphate monoanion at 25 °C are 5.2 × 103, 1.6 × 104, 8.0 × 105, and > 2 × 106, respectively. We have been involved in developing technologies by using the Phos-tag molecule and its derivatives to permit the analysis of phosphorylated biomolecules. To date, Phos-tag technology has contributed to the development of several procedures for phosphoproteomics, including a phosphate-affinity chromatography technique for the separation and enrichment of phosphopeptides and phosphoproteins, a wide variety of microarray/on-chip techniques for the detection of protein phosphorylation, and a phosphate-affinity electrophoresis technique for the detection of shifts in the mobilities of phosphoproteins. In this review article, the authors introduce the impact of Phos-tag-based technological advances for phosphoproteomics.
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Affiliation(s)
- Eiji Kinoshita
- Department of Human Nutrition, Faculty of Human Sciences, Hiroshima Bunkyo University, Kabehigashi 1-2-1, Asakita-ku, Hiroshima 731-0295, Japan.
| | - Emiko Kinoshita-Kikuta
- Department of Functional Molecular Science, Graduate School of Biomedical & Health Sciences, Hiroshima University, Kasumi 1-2-3, Minami-ku, Hiroshima 734-8553, Japan
| | - Tohru Koike
- Department of Functional Molecular Science, Graduate School of Biomedical & Health Sciences, Hiroshima University, Kasumi 1-2-3, Minami-ku, Hiroshima 734-8553, Japan
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Phos-Tag Fluorescent Gel Staining for the Quantitative Detection of His- and Asp-Phosphorylated Proteins. Methods Mol Biol 2021; 2261:73-78. [PMID: 33420985 DOI: 10.1007/978-1-0716-1186-9_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
We describe a standard protocol for phosphate-affinity fluorescent gel staining that uses a fluorophore-labeled dizinc(II) complex of a derivative of the phosphate-binding tag molecule Phos-tag to detect His- and Asp-phosphorylated proteins separated by SDS-PAGE. The procedure permits the quantitative monitoring of phosphorylated histidine kinases (His-phosphoproteins) and their cognate phosphorylated response regulators (Asp-phosphoproteins) in bacterial two-component signaling transduction systems. The total time required for each gel staining operation is about 2 h at room temperature.
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Abstract
Posttranslational modification (PTM) of proteins occurs during or after translation and in most cases means covalent binding of a functional group to certain amino acid side chains. Among PTMs, phosphorylation is extensively studied for decades. During phosphorylation, a phosphate group is added to the target residue that is dominantly serine, threonine, and tyrosine in eukaryotes. The phosphate group attachment is catalyzed by kinases, whereas the removal of phosphate (dephosphorylation) is performed by phosphatases. Phosphorylation of phytochrome photoreceptors alters light signaling in multiple ways, thus the examination of this PTM is an expanding aspect of light signaling research. Although this chapter presents methods for detecting phosphorylated phytochrome B molecules, it can be applied on other phytochrome species. The first presented protocol of this chapter shows how the phosphorylation state of phytochrome photoreceptors can be monitored in a modified polyacrylamide gel electrophoresis system. The second protocol describes in detail how phosphorylated amino acids of a target molecule can be identified using mass spectrometry analysis.
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Affiliation(s)
- Eva Klement
- Laboratory of Proteomics Research, Biological Research Centre, Szeged, Hungary
| | - Péter Gyula
- Agricultural Biotechnology Institute, National Agricultural Research and Innovation Centre, Gödöllő, Hungary
| | - András Viczián
- Plant Biology Institute, Biological Research Centre, Szeged, Hungary.
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Kruglova NA, Meshkova TD, Kopylov AT, Mazurov DV, Filatov AV. Constitutive and activation-dependent phosphorylation of lymphocyte phosphatase-associated phosphoprotein (LPAP). PLoS One 2017; 12:e0182468. [PMID: 28827793 PMCID: PMC5565103 DOI: 10.1371/journal.pone.0182468] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Accepted: 07/19/2017] [Indexed: 12/15/2022] Open
Abstract
Lymphocyte phosphatase-associated phosphoprotein (LPAP) is a small transmembrane protein expressed exclusively in lymphocytes. LPAP is a component of a supramolecular complex composed of the phosphatase CD45, the co-receptor CD4, and the kinase Lck. In contrast to its immunologically important partners, the function of LPAP is unknown. We hypothesized that the biological role of LPAP may be determined by analyzing LPAP phosphorylation. In the present study, we identified LPAP phosphorylation sites by site-directed mutagenesis, phospho-specific antibodies, and protein immunoprecipitation coupled to mass spectrometry analysis. Our results confirmed previous reports that Ser-99, Ser-153, and Ser-163 are phosphorylated, as well as provided evidence for the phosphorylation of Ser-172. Using various SDS-PAGE techniques, we detected and quantified a set of LPAP phosphoforms that were assigned to a combination of particular phosphorylation events. The phosphorylation of LPAP appears to be a tightly regulated process. Our results support the model: following phorbol 12-myristate 13-acetate (PMA) or TCR/CD3 activation of T cells, LPAP is rapidly dephosphorylated at Ser-99 and Ser-172 and slowly phosphorylated at Ser-163. Ser-153 exhibited a high basal level of phosphorylation in both resting and activated cells. Therefore, we suggest that LPAP may function as a co-regulator of T-cell signaling.
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Schummer A, Fischer S, Oeljeklaus S, Warscheid B. Study of Peroxisomal Protein Phosphorylation by Functional Proteomics. Methods Mol Biol 2017; 1595:267-289. [PMID: 28409471 DOI: 10.1007/978-1-4939-6937-1_26] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Reversible protein phosphorylation is a frequently occurring posttranslational modification mediated by protein kinases and phosphatases that plays an essential role in the regulation of a large number of cellular processes. Evidence is accumulating that protein phosphorylation is also an important mechanism governing processes associated with peroxisome biology. For an improved and detailed understanding of these processes and their regulation it is therefore crucial to study phosphorylation of peroxisome-associated proteins and to determine the phosphorylated amino acid(s). To place peroxisome-related processes into a larger, cellular context, it is further required to identify the kinases and phosphatases catalyzing phosphorylation and dephosphorylation events in peroxisomal proteins. We here provide a strategy for the targeted analysis of peroxisomal phosphoproteins of Saccharomyces cerevisiae combining affinity purification of epitope-tagged peroxisomal proteins with Phos-tag SDS-PAGE and high-resolution mass spectrometry (MS) for the identification and precise localization of in vivo phosphosites. Furthermore, we describe a protocol for an MS-based in vitro kinase assay using recombinant peroxisomal proteins and a selected kinase facilitating the site-resolved analysis of kinase-substrate relationships.
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Affiliation(s)
- Andreas Schummer
- Department of Biochemistry and Functional Proteomics, Institute of Biology II, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104, Freiburg, Germany
| | - Sven Fischer
- Department of Biochemistry and Functional Proteomics, Institute of Biology II, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104, Freiburg, Germany
| | - Silke Oeljeklaus
- Department of Biochemistry and Functional Proteomics, Institute of Biology II, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104, Freiburg, Germany.
| | - Bettina Warscheid
- Department of Biochemistry and Functional Proteomics, Institute of Biology II, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104, Freiburg, Germany.
- BIOSS Centre for Biological Signalling Studies, University of Freiburg, Schänzlestr. 18, 79104, Freiburg, Germany.
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Le NH, Molle V, Eynard N, Miras M, Stella A, Bardou F, Galandrin S, Guillet V, André-Leroux G, Bellinzoni M, Alzari P, Mourey L, Burlet-Schiltz O, Daffé M, Marrakchi H. Ser/Thr Phosphorylation Regulates the Fatty Acyl-AMP Ligase Activity of FadD32, an Essential Enzyme in Mycolic Acid Biosynthesis. J Biol Chem 2016; 291:22793-22805. [PMID: 27590338 DOI: 10.1074/jbc.m116.748053] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 08/31/2016] [Indexed: 12/21/2022] Open
Abstract
Mycolic acids are essential components of the mycobacterial cell envelope, and their biosynthetic pathway is a well known source of antituberculous drug targets. Among the promising new targets in the pathway, FadD32 is an essential enzyme required for the activation of the long meromycolic chain of mycolic acids and is essential for mycobacterial growth. Following the in-depth biochemical, biophysical, and structural characterization of FadD32, we investigated its putative regulation via post-translational modifications. Comparison of the fatty acyl-AMP ligase activity between phosphorylated and dephosphorylated FadD32 isoforms showed that the native protein is phosphorylated by serine/threonine protein kinases and that this phosphorylation induced a significant loss of activity. Mass spectrometry analysis of the native protein confirmed the post-translational modifications and identified Thr-552 as the phosphosite. Phosphoablative and phosphomimetic FadD32 mutant proteins confirmed both the position and the importance of the modification and its correlation with the negative regulation of FadD32 activity. Investigation of the mycolic acid condensation reaction catalyzed by Pks13, involving FadD32 as a partner, showed that FadD32 phosphorylation also impacts the condensation activity. Altogether, our results bring to light FadD32 phosphorylation by serine/threonine protein kinases and its correlation with the enzyme-negative regulation, thus shedding a new horizon on the mycolic acid biosynthesis modulation and possible inhibition strategies for this promising drug target.
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Affiliation(s)
- Nguyen-Hung Le
- From the Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS
| | - Virginie Molle
- the Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Université de Montpellier, CNRS UMR 5235, Place Eugène Bataillon, 34095 Montpellier Cedex 05, and
| | - Nathalie Eynard
- From the Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS
| | - Mathieu Miras
- From the Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS
| | - Alexandre Stella
- From the Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS
| | - Fabienne Bardou
- From the Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS
| | - Ségolène Galandrin
- From the Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS
| | - Valérie Guillet
- From the Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS
| | - Gwenaëlle André-Leroux
- the Institut Pasteur, Unité de Microbiologie Structurale, 25 Rue du Docteur Roux, 75724 Paris Cedex 15, France
| | - Marco Bellinzoni
- the Institut Pasteur, Unité de Microbiologie Structurale, 25 Rue du Docteur Roux, 75724 Paris Cedex 15, France
| | - Pedro Alzari
- the Institut Pasteur, Unité de Microbiologie Structurale, 25 Rue du Docteur Roux, 75724 Paris Cedex 15, France
| | - Lionel Mourey
- From the Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS
| | - Odile Burlet-Schiltz
- From the Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS
| | - Mamadou Daffé
- From the Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS,
| | - Hedia Marrakchi
- From the Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS,
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Kinoshita E, Kinoshita-Kikuta E, Kubota Y, Takekawa M, Koike T. A Phos-tag SDS-PAGE method that effectively uses phosphoproteomic data for profiling the phosphorylation dynamics of MEK1. Proteomics 2016; 16:1825-36. [DOI: 10.1002/pmic.201500494] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 04/14/2016] [Accepted: 05/02/2016] [Indexed: 12/11/2022]
Affiliation(s)
- Eiji Kinoshita
- Department of Functional Molecular Science; Institute of Biomedical and Health Sciences; Hiroshima University; Japan
| | - Emiko Kinoshita-Kikuta
- Department of Functional Molecular Science; Institute of Biomedical and Health Sciences; Hiroshima University; Japan
| | - Yuji Kubota
- Division of Cell Signaling and Molecular Medicine; Institute of Medical Science; The University of Tokyo; Japan
| | - Mutsuhiro Takekawa
- Division of Cell Signaling and Molecular Medicine; Institute of Medical Science; The University of Tokyo; Japan
| | - Tohru Koike
- Department of Functional Molecular Science; Institute of Biomedical and Health Sciences; Hiroshima University; Japan
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Filatov A, Kruglova N, Meshkova T, Mazurov D. Lymphocyte phosphatase-associated phosphoprotein proteoforms analyzed using monoclonal antibodies. Clin Transl Immunology 2015; 4:e44. [PMID: 26682052 PMCID: PMC4673442 DOI: 10.1038/cti.2015.22] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 09/03/2015] [Accepted: 09/03/2015] [Indexed: 11/09/2022] Open
Abstract
Phosphatase CD45 regulates the activation of lymphocytes by controlling the level of receptor and signal molecule phosphorylation. However, it remains unknown which molecules mediate the phosphatase activity of CD45. A candidate for such a molecule is a small transmembrane adapter protein called lymphocyte phosphatase-associated phosphoprotein (LPAP). LPAP forms a supramolecular complex that consists of not only CD45 molecule but also CD4 and Lck kinase. The function of LPAP has not been defined clearly. In our study, we determined the pattern of LPAP expression in various cell types and characterized its proteoforms using new monoclonal antibodies generated against the intracellular portion of the protein. We show that LPAP is a pan-lymphocyte marker, and its expression in cells correlates with the expression of CD45. The majority of T, B and NK cells express high levels of LPAP, whereas monocytes, granulocytes, monocyte-derived dendritic cells, platelets and red blood cells are negative for LPAP. Using one- and two-dimensional protein gel electrophoresis, we demonstrate that LPAP has at least four sites of phosphorylation. The resting cells express at least six different LPAP phosphoforms representing mono-, di- and tri-phosphorylated LPAP. T and B cells differ in the distribution of the protein between phosphoforms. The activation of lymphocytes with PMA reduces the diversity of phosphorylated forms. Our experiments on Lck-deficient Jurkat cells show that Lck kinase is not involved in LPAP phosphorylation. Thus, LPAP is a dynamically phosphorylated protein, the function of which can be understood, when all phosphosites and kinases involved in its phosphorylation will be identified.
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Affiliation(s)
- Alexander Filatov
- Laboratory of Immunochemistry, Institute of Immunology , Moscow, Russia
| | - Natalia Kruglova
- Faculty of Biology, Lomonosov Moscow State University , Moscow, Russia
| | - Tatiana Meshkova
- Faculty of Biology, Lomonosov Moscow State University , Moscow, Russia
| | - Dmitriy Mazurov
- Laboratory of Immunochemistry, Institute of Immunology , Moscow, Russia
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