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Amino Acids 785, 787 of the Na +/H + Exchanger Cytoplasmic Tail Modulate Protein Activity and Tail Conformation. Int J Mol Sci 2021; 22:ijms222111349. [PMID: 34768780 PMCID: PMC8583816 DOI: 10.3390/ijms222111349] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 10/14/2021] [Accepted: 10/18/2021] [Indexed: 11/30/2022] Open
Abstract
The mammalian Na+/H+ exchanger isoform 1 (NHE1) is a plasma membrane protein ubiquitously present in humans. It regulates intracellular pH by removing an intracellular proton in exchange for an extracellular sodium. It consists of a 500 amino acid membrane domain plus a 315 amino acid, regulatory cytosolic tail. Here, we investigated the effect of mutation of two amino acids of the regulatory tail, Ser785 and Ser787, that were similar in location and context to two amino acids of the Arabidopsis Na+/H+ exchanger SOS1. Mutation of these two amino acids to either Ala or phosphomimetic Glu did not affect surface targeting but led to a slight reduction in the level of protein expressed. The activity of the NHE1 protein was reduced in the phosphomimetic mutations and the effect was due to a decrease in Vmax activity. The Ser to Glu mutations also caused a change in the apparent molecular weight of both the full-length protein and of the cytosolic tail of NHE1. A conformational change in this region was indicated by differential trypsin sensitivity. We also found that a peptide containing amino acids 783–790 bound to several more proximal regions of the NHE1 tail in in vitro protein interaction experiments. The results are the first characterization of these two amino acids and show that they have significant effects on enzyme kinetics and the structure of the NHE1 protein.
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Pedersen SF, Counillon L. The SLC9A-C Mammalian Na +/H + Exchanger Family: Molecules, Mechanisms, and Physiology. Physiol Rev 2019; 99:2015-2113. [PMID: 31507243 DOI: 10.1152/physrev.00028.2018] [Citation(s) in RCA: 103] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Na+/H+ exchangers play pivotal roles in the control of cell and tissue pH by mediating the electroneutral exchange of Na+ and H+ across cellular membranes. They belong to an ancient family of highly evolutionarily conserved proteins, and they play essential physiological roles in all phyla. In this review, we focus on the mammalian Na+/H+ exchangers (NHEs), the solute carrier (SLC) 9 family. This family of electroneutral transporters constitutes three branches: SLC9A, -B, and -C. Within these, each isoform exhibits distinct tissue expression profiles, regulation, and physiological roles. Some of these transporters are highly studied, with hundreds of original articles, and some are still only rudimentarily understood. In this review, we present and discuss the pioneering original work as well as the current state-of-the-art research on mammalian NHEs. We aim to provide the reader with a comprehensive view of core knowledge and recent insights into each family member, from gene organization over protein structure and regulation to physiological and pathophysiological roles. Particular attention is given to the integrated physiology of NHEs in the main organ systems. We provide several novel analyses and useful overviews, and we pinpoint main remaining enigmas, which we hope will inspire novel research on these highly versatile proteins.
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Affiliation(s)
- S F Pedersen
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark; and Université Côte d'Azur, CNRS, Laboratoire de Physiomédecine Moléculaire, LP2M, France, and Laboratories of Excellence Ion Channel Science and Therapeutics, Nice, France
| | - L Counillon
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark; and Université Côte d'Azur, CNRS, Laboratoire de Physiomédecine Moléculaire, LP2M, France, and Laboratories of Excellence Ion Channel Science and Therapeutics, Nice, France
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Structural and Functional Changes in the Na +/H + Exchanger Isoform 1, Induced by Erk1/2 Phosphorylation. Int J Mol Sci 2019; 20:ijms20102378. [PMID: 31091671 PMCID: PMC6566726 DOI: 10.3390/ijms20102378] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 05/08/2019] [Accepted: 05/09/2019] [Indexed: 12/15/2022] Open
Abstract
The human Na+/H+ exchanger isoform 1 (NHE1) is a plasma membrane transport protein that plays an important role in pH regulation in mammalian cells. Because of the generation of protons by intermediary metabolism as well as the negative membrane potential, protons accumulate within the cytosol. Extracellular signal-regulated kinase (ERK)-mediated regulation of NHE1 is important in several human pathologies including in the myocardium in heart disease, as well as in breast cancer as a trigger for growth and metastasis. NHE1 has a N-terminal, a 500 amino acid membrane domain, and a C-terminal 315 amino acid cytosolic domain. The C-terminal domain regulates the membrane domain and its effects on transport are modified by protein binding and phosphorylation. Here, we discuss the physiological regulation of NHE1 by ERK, with an emphasis on the critical effects on structure and function. ERK binds directly to the cytosolic domain at specific binding domains. ERK also phosphorylates NHE1 directly at multiple sites, which enhance NHE1 activity with subsequent downstream physiological effects. The NHE1 cytosolic regulatory tail possesses both ordered and disordered regions, and the disordered regions are stabilized by ERK-mediated phosphorylation at a phosphorylation motif. Overall, ERK pathway mediated phosphorylation modulates the NHE1 tail, and affects the activity, structure, and function of this membrane protein.
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A new method for high-resolution and high-precision analysis of flunitrazepam and 7-aminoflunitrazepam in human body fluids using a Monolithic SPE SpinTip and UPLC–Q-ToF–MS. Forensic Toxicol 2019. [DOI: 10.1007/s11419-019-00471-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Díaz RG, Escudero DS, Brea MS, Morgan PE, Pérez NG. p38 mitogen activated protein kinase mediates cardiac Na +/H + exchanger inhibition induced by Sildenafil. Eur J Pharmacol 2019; 849:96-105. [PMID: 30721701 DOI: 10.1016/j.ejphar.2019.01.070] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 01/11/2019] [Accepted: 01/21/2019] [Indexed: 10/27/2022]
Abstract
Since the original description as potent antianginal compounds, phosphodiesterase 5A inhibitors have continuously increased their possible therapeutic applications. In the heart, Sildenafil was shown to protect against an ischemic insult by decreasing cardiac Na+/H+ exchanger (NHE1) activity, action that was mediated by protein kinase G. p38 mitogen activated protein kinase (p38MAPK) activation was described in cardiac ischemia, but its precise role remains elusive. It has been shown that p38MAPK is activated by protein kinase G (PKG) in certain non-cardiac tissues, while in others modulates NHE1 activity. Current study was aimed to seek the role of p38MAPK in the Sildenafil-triggered pathway leading to NHE1 inhibition in myocardium. Rat isolated papillary muscles were used to evaluate NHE1 activity during intracellular pH recovery from an acidic load. Protein kinases phosphorylation (activation) was determined by western blot. Sustained acidosis promoted NHE1 hyperactivity by enhancing Ser703 phosphorylation, effect that was blunted by Sildenafil. p38MAPK inhibition reversed the effect of Sildenafil on NHE1. Activation of p38MAPK, by Sodium Arsenite or Anisomycin, mimicked the inhibitory effect of Sildenafil on the exchanger. Consistently, Sildenafil induced p38MAPK phosphorylation/activation during acidosis. Neither Sildenafil nor p38MAPK inhibition affected extracellular signal-regulated kinases 1/2 phosphorylation, kinases upstream NHE1. Furthermore, inhibition of NHE1 after p38MAPK activation was precluded by preventing the activation of protein phosphatase 2A with Okadaic Acid. Taken together, these results suggest that activation of p38MAPK is a necessary step to trigger the inhibitory effect of Sildenafil on cardiac NHE1 activity, thorough a mechanism that involves protein phosphatase 2A-mediated exchanger dephosphorylation.
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Affiliation(s)
- Romina G Díaz
- Centro de Investigaciones Cardiovasculares "Dr. Horacio E. Cingolani", Facultad de Ciencias Médicas, Universidad Nacional de La Plata, Calle 60 y 120, 1900 La Plata, Argentina
| | - Daiana S Escudero
- Centro de Investigaciones Cardiovasculares "Dr. Horacio E. Cingolani", Facultad de Ciencias Médicas, Universidad Nacional de La Plata, Calle 60 y 120, 1900 La Plata, Argentina
| | - María S Brea
- Centro de Investigaciones Cardiovasculares "Dr. Horacio E. Cingolani", Facultad de Ciencias Médicas, Universidad Nacional de La Plata, Calle 60 y 120, 1900 La Plata, Argentina
| | - Patricio E Morgan
- Centro de Investigaciones Cardiovasculares "Dr. Horacio E. Cingolani", Facultad de Ciencias Médicas, Universidad Nacional de La Plata, Calle 60 y 120, 1900 La Plata, Argentina.
| | - Néstor G Pérez
- Centro de Investigaciones Cardiovasculares "Dr. Horacio E. Cingolani", Facultad de Ciencias Médicas, Universidad Nacional de La Plata, Calle 60 y 120, 1900 La Plata, Argentina.
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Amith SR, Wilkinson JM, Fliegel L. Na+/H+ exchanger NHE1 regulation modulates metastatic potential and epithelial-mesenchymal transition of triple-negative breast cancer cells. Oncotarget 2018; 7:21091-113. [PMID: 27049728 PMCID: PMC5008271 DOI: 10.18632/oncotarget.8520] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 03/24/2016] [Indexed: 12/20/2022] Open
Abstract
In triple-negative breast cancer (TNBC), the high recurrence rate, increased invasion and aggressive metastatic formation dictate patient survival. We previously demonstrated a critical role for the Na+/H+ exchanger isoform 1 (NHE1) in controlling metastasis of triple-negative cells. Here, we investigated the effect of changes to three regulatory loci of NHE1. Two via the Ras/Raf/ERK/p90RSK pathway: p90RSK/14-3-3 (S703A) and ERK1/2 (S766,770,771A, SSSA) and a third via a calmodulin-binding domain (K641,R643,645,647E, 1K3R4E). MDA-MB-231 cells with a mutation at the p90RSK site (S703A-NHE1) changed from a wild-type mesenchymal morphology to a smaller epithelial-like phenotype with a loss of expression of mesenchymal marker vimentin. S703A cells also had reduced metastatic potential and markedly decreased rates of migration, invasion, spheroid growth, anchorage-dependent and soft agar colony formation. Similarly, BI-D1870, a specific inhibitor of p90RSK, significantly inhibited the metastatic potential of highly invasive MDA-MB-231 and moderately invasive MDA-MB-468 TNBC cells, but was minimally effective in non-invasive Hs578T TNBC cells. In contrast, invasion and spheroid growth were unaffected in cells containing NHE1 with mutations interfering with its activation by ERK1/2 (SSSA), though rates of migration and colony formation were reduced. Cells with a constitutive activation of NHE1 via the 1K3R4E mutation exhibited higher rates of migration, invasion, and spheroid growth. Taken together, our data demonstrate the critical role of NHE1 in metastasis, and suggest a novel link between NHE1 and the expression and cytosolic organization of vimentin, a key factor in epithelial-mesenchymal transition, that is dependent on p90RSK/14-3-3-mediated activation of the exchanger.
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Affiliation(s)
- Schammim Ray Amith
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | | | - Larry Fliegel
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
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Dumas JF, Brisson L, Chevalier S, Mahéo K, Fromont G, Moussata D, Besson P, Roger S. Metabolic reprogramming in cancer cells, consequences on pH and tumour progression: Integrated therapeutic perspectives with dietary lipids as adjuvant to anticancer treatment. Semin Cancer Biol 2017; 43:90-110. [DOI: 10.1016/j.semcancer.2017.03.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Revised: 03/10/2017] [Accepted: 03/13/2017] [Indexed: 02/07/2023]
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Hendus-Altenburger R, Pedraz-Cuesta E, Olesen CW, Papaleo E, Schnell JA, Hopper JTS, Robinson CV, Pedersen SF, Kragelund BB. The human Na(+)/H(+) exchanger 1 is a membrane scaffold protein for extracellular signal-regulated kinase 2. BMC Biol 2016; 14:31. [PMID: 27083547 PMCID: PMC4833948 DOI: 10.1186/s12915-016-0252-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 03/29/2016] [Indexed: 11/22/2022] Open
Abstract
Background Extracellular signal-regulated kinase 2 (ERK2) is an S/T kinase with more than 200 known substrates, and with critical roles in regulation of cell growth and differentiation and currently no membrane proteins have been linked to ERK2 scaffolding. Methods and results Here, we identify the human Na+/H+ exchanger 1 (hNHE1) as a membrane scaffold protein for ERK2 and show direct hNHE1-ERK1/2 interaction in cellular contexts. Using nuclear magnetic resonance (NMR) spectroscopy and immunofluorescence analysis we demonstrate that ERK2 scaffolding by hNHE1 occurs by one of three D-domains and by two non-canonical F-sites located in the disordered intracellular tail of hNHE1, mutation of which reduced cellular hNHE1-ERK1/2 co-localization, as well as reduced cellular ERK1/2 activation. Time-resolved NMR spectroscopy revealed that ERK2 phosphorylated the disordered tail of hNHE1 at six sites in vitro, in a distinct temporal order, with the phosphorylation rates at the individual sites being modulated by the docking sites in a distant dependent manner. Conclusions This work characterizes a new type of scaffolding complex, which we term a “shuffle complex”, between the disordered hNHE1-tail and ERK2, and provides a molecular mechanism for the important ERK2 scaffolding function of the membrane protein hNHE1, which regulates the phosphorylation of both hNHE1 and ERK2. Electronic supplementary material The online version of this article (doi:10.1186/s12915-016-0252-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ruth Hendus-Altenburger
- Cell and Developmental Biology, Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen Ø, Denmark.,Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, DK-2200, Copenhagen N, Denmark
| | - Elena Pedraz-Cuesta
- Cell and Developmental Biology, Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen Ø, Denmark
| | - Christina W Olesen
- Cell and Developmental Biology, Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen Ø, Denmark
| | - Elena Papaleo
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, DK-2200, Copenhagen N, Denmark
| | - Jeff A Schnell
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, DK-2200, Copenhagen N, Denmark
| | - Jonathan T S Hopper
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QZ, UK
| | - Carol V Robinson
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QZ, UK
| | - Stine F Pedersen
- Cell and Developmental Biology, Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen Ø, Denmark.
| | - Birthe B Kragelund
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, DK-2200, Copenhagen N, Denmark.
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Odunewu-Aderibigbe A, Fliegel L. The Na+/H+exchanger and pH regulation in the heart. IUBMB Life 2014; 66:679-85. [DOI: 10.1002/iub.1323] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2014] [Accepted: 10/15/2014] [Indexed: 11/11/2022]
Affiliation(s)
| | - Larry Fliegel
- Department of Biochemistry; University of Alberta; Edmonton AB Canada
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Sun X, Chiu JF, He QY. Application of immobilized metal affinity chromatography in proteomics. Expert Rev Proteomics 2014; 2:649-57. [PMID: 16209645 DOI: 10.1586/14789450.2.5.649] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
It has been proved that the progress of proteomics is mostly determined by the development of advanced and sensitive protein separation technologies. Immobilized metal affinity chromatography (IMAC) is a powerful protein fractionation method used to enrich metal-associated proteins and peptides. In proteomics, IMAC has been widely employed as a prefractionation method to increase the resolution in protein separation. The combination of IMAC with other protein analytical technologies has been successfully utilized to characterize metalloproteome and post-translational modifications. In the near future, newly developed IMAC integrated with other proteomic methods will greatly contribute to the revolution of expression, cell-mapping and structural proteomics.
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Affiliation(s)
- Xuesong Sun
- Department of Chemistry, University of Hong Kong, Pokfulam, Hong Kong.
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Piatkivskyi A, Pyatkivskyy Y, Ryzhov V. Evaluation of various silicon-and boron-containing compounds for the detection of phosphorylation in peptides via gas-phase ion-molecule reactions. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2014; 20:337-344. [PMID: 25420346 DOI: 10.1255/ejms.1286] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Gas-phase ion-molecule reactions [IMR] of various boron- and silicon-containing neutrals were investigated as a potential route for detecting phosphorylation within peptides in the negative ion mode. Trimethyl borate (TMB), triethyl borate (TEB) and N,O- Bis(trimethylsilyl)acetamide (TMSA), unlike diethylmethoxyborane (DEMB), diisopropoxymethylborane [DiPMB] and chlorotrimethylsi- Lane (TMSCIL], reacted differently if a phosphate moiety was present and thus are suitable to detect phosphorylation. During multistage collision-induced dissociation experiments of the reaction products of IMR with TMB and TEB, the [LSsF - 4H + B]- ion formed a modified y2 fragment allowing the phosphorylation site to be assigned, unlike reaction products of DEMB and DiPMB which lost both the phos- phoric acid and the boron-containing moiety.
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12
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Hendus-Altenburger R, Kragelund BB, Pedersen SF. Structural dynamics and regulation of the mammalian SLC9A family of Na⁺/H⁺ exchangers. CURRENT TOPICS IN MEMBRANES 2014; 73:69-148. [PMID: 24745981 DOI: 10.1016/b978-0-12-800223-0.00002-5] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Mammalian Na⁺/H⁺ exchangers of the SLC9A family are widely expressed and involved in numerous essential physiological processes. Their primary function is to mediate the 1:1 exchange of Na⁺ for H⁺ across the membrane in which they reside, and they play central roles in regulation of body, cellular, and organellar pH. Their function is tightly regulated through mechanisms involving interactions with multiple protein and lipid-binding partners, phosphorylations, and other posttranslational modifications. Biochemical and mutational analyses indicate that the SLC9As have a short intracellular N-terminus, 12 transmembrane (TM) helices necessary and sufficient for ion transport, and a C-terminal cytoplasmic tail region with essential regulatory roles. No high-resolution structures of the SLC9As exist; however, models based on crystal structures of the bacterial NhaAs support the 12 TM organization and suggest that TMIV and XI may form a central part of the ion-translocation pathway, whereas pH sensing may involve TMII, TMIX, and several intracellular loops. Similar to most ion transporters studied, SLC9As likely exist as coupled dimers in the membrane, and this appears to be important for the well-studied cooperativity of H⁺ binding. The aim of this work is to summarize and critically discuss the currently available evidence on the structural dynamics, regulation, and binding partner interactions of SLC9As, focusing in particular on the most widely studied isoform, SLC9A1/NHE1. Further, novel bioinformatic and structural analyses are provided that to some extent challenge the existing paradigm on how ions are transported by mammalian SLC9As.
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Affiliation(s)
- Ruth Hendus-Altenburger
- Section for Biomolecular Sciences, Department of Biology, University of Copenhagen, Copenhagen, Denmark; Section for Cell and Developmental Biology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Birthe B Kragelund
- Section for Biomolecular Sciences, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Stine Falsig Pedersen
- Section for Cell and Developmental Biology, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
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Huang SY, Hsu JL, Chen SH. Two-step Immobilized Metal Affinity Chromatography (IMAC) for Phosphoproteomics Using Mass Spectrometry. J CHIN CHEM SOC-TAIP 2013. [DOI: 10.1002/jccs.200500107] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Odunewu A, Fliegel L. Acidosis-mediated regulation of the NHE1 isoform of the Na⁺/H⁺ exchanger in renal cells. Am J Physiol Renal Physiol 2013; 305:F370-81. [PMID: 23678047 DOI: 10.1152/ajprenal.00598.2012] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The mammalian Na⁺/H⁺ exchanger isoform 1 (NHE1) is a ubiquitous plasma membrane protein that regulates intracellular pH by removing a proton in exchange for extracellular sodium. Renal tissues are subject to metabolic and respiratory acidosis, and acidosis has been shown to acutely activate NHE1 activity in other cell types. We examined if NHE1 is activated by acute acidosis in HEK293 and Madin-Darby canine kidney (MDCK) cells. Acute sustained intracellular acidosis (SIA) activated NHE1 in both cell types. We expressed wild-type and mutant NHE1 cDNAs in MDCK cells. All the cDNAs had a L163F/G174S mutation, which conferred a 100-fold resistance to EMD87580, an NHE1-specific inhibitor. We assayed exogenous NHE1 activity while inhibiting endogenous activity with EMD87580 and while inhibiting the NHE3 isoform of the Na⁺/H⁺ exchanger using the isoform-specific inhibitor S3226. We examined the activation and phosphorylation of the wild-type and mutant NHE1 proteins in response to SIA. In MDCK cells we demonstrated that the amino acids Ser⁷⁷¹, Ser⁷⁷⁶, Thr⁷⁷⁹, and Ser⁷⁸⁵ are important for NHE1 phosphorylation and activation after acute SIA. SIA activated ERK-dependent pathways in MDCK cells, and this was blocked by treatment with the MEK inhibitor U0126. Treatment with U0126 also blocked activation of NHE1 by SIA. These results suggest that acute acidosis activates NHE1 in mammalian kidney cells and that in MDCK cells this activation occurs through an ERK-dependent pathway affecting phosphorylation of a distinct set of amino acids in the cytosolic regulatory tail of NHE1.
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Affiliation(s)
- Ayodeji Odunewu
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
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15
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Huang SY, Chen YC. Magnetic Nanoparticle-Based Platform for Characterization of Histidine-Rich Proteins and Peptides. Anal Chem 2013; 85:3347-54. [DOI: 10.1021/ac4000128] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Shin-Yi Huang
- Department of Applied Chemistry, National Chiao Tung University, Hsinchu 300, Taiwan
| | - Yu-Chie Chen
- Department of Applied Chemistry, National Chiao Tung University, Hsinchu 300, Taiwan
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16
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17
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Dong M, Ye M, Cheng K, Song C, Pan Y, Wang C, Bian Y, Zou H. Depletion of Acidic Phosphopeptides by SAX To Improve the Coverage for the Detection of Basophilic Kinase Substrates. J Proteome Res 2012; 11:4673-81. [DOI: 10.1021/pr300503z] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mingming Dong
- CAS Key Lab
of Separation Sciences
for Analytical Chemistry, National Chromatographic Research and Analysis
Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- Graduate School of Chinese Academy of Sciences, Beijing 100049, China
| | - Mingliang Ye
- CAS Key Lab
of Separation Sciences
for Analytical Chemistry, National Chromatographic Research and Analysis
Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Kai Cheng
- CAS Key Lab
of Separation Sciences
for Analytical Chemistry, National Chromatographic Research and Analysis
Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- Graduate School of Chinese Academy of Sciences, Beijing 100049, China
| | - Chunxia Song
- CAS Key Lab
of Separation Sciences
for Analytical Chemistry, National Chromatographic Research and Analysis
Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- Graduate School of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanbo Pan
- CAS Key Lab
of Separation Sciences
for Analytical Chemistry, National Chromatographic Research and Analysis
Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- Graduate School of Chinese Academy of Sciences, Beijing 100049, China
| | - Chunli Wang
- CAS Key Lab
of Separation Sciences
for Analytical Chemistry, National Chromatographic Research and Analysis
Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- Graduate School of Chinese Academy of Sciences, Beijing 100049, China
| | - Yangyang Bian
- CAS Key Lab
of Separation Sciences
for Analytical Chemistry, National Chromatographic Research and Analysis
Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- Graduate School of Chinese Academy of Sciences, Beijing 100049, China
| | - Hanfa Zou
- CAS Key Lab
of Separation Sciences
for Analytical Chemistry, National Chromatographic Research and Analysis
Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
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18
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Serafino A, Moroni N, Psaila R, Zonfrillo M, Andreola F, Wannenes F, Mercuri L, Rasi G, Pierimarchi P. Anti-proliferative effect of atrial natriuretic peptide on colorectal cancer cells: Evidence for an Akt-mediated cross-talk between NHE-1 activity and Wnt/β-catenin signaling. Biochim Biophys Acta Mol Basis Dis 2012; 1822:1004-18. [DOI: 10.1016/j.bbadis.2012.02.016] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Revised: 02/14/2012] [Accepted: 02/15/2012] [Indexed: 01/26/2023]
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19
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Atakay M, Çelikbıçak Ö, Salih B. Amine-Functionalized Sol–Gel-Based Lab-in-a-Pipet-Tip Approach for the Fast Enrichment and Specific Purification of Phosphopeptides in MALDI-MS Applications. Anal Chem 2012; 84:2713-20. [DOI: 10.1021/ac203008u] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Mehmet Atakay
- Hacettepe University, Department
of Chemistry, 06800 Ankara, Turkey
| | - Ömür Çelikbıçak
- Hacettepe University, Department
of Chemistry, 06800 Ankara, Turkey
| | - Bekir Salih
- Hacettepe University, Department
of Chemistry, 06800 Ankara, Turkey
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20
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Phosphorylation and activation of the plasma membrane Na+/H+ exchanger (NHE1) during osmotic cell shrinkage. PLoS One 2011; 6:e29210. [PMID: 22216214 PMCID: PMC3247252 DOI: 10.1371/journal.pone.0029210] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Accepted: 11/22/2011] [Indexed: 11/19/2022] Open
Abstract
The Na(+)/H(+)Exchanger isoform 1 (NHE1) is a highly versatile, broadly distributed and precisely controlled transport protein that mediates volume and pH regulation in most cell types. NHE1 phosphorylation contributes to Na(+)/H(+) exchange activity in response to phorbol esters, growth factors or protein phosphatase inhibitors, but has not been observed during activation by osmotic cell shrinkage (OCS). We examined the role of NHE1 phosphorylation during activation by OCS, using an ideal model system, the Amphiuma tridactylum red blood cell (atRBC). Na(+)/H(+) exchange in atRBCs is mediated by an NHE1 homolog (atNHE1) that is 79% identical to human NHE1 at the amino acid level. NHE1 activity in atRBCs is exceptionally robust in that transport activity can increase more than 2 orders of magnitude from rest to full activation. Michaelis-Menten transport kinetics indicates that either OCS or treatment with the phosphatase inhibitor calyculin-A (CLA) increase Na(+) transport capacity without affecting transport affinity (K(m)=44 mM) in atRBCs. CLA and OCS act non-additively to activate atNHE1, indicating convergent, phosphorylation-dependent signaling in atNHE1 activation. In situ(32)P labeling and immunoprecipitation demonstrates that the net phosphorylation of atNHE1 is increased 4-fold during OCS coinciding with a more than 2-order increase in Na(+) transport activity. This is the first reported evidence of increased NHE1 phosphorylation during OCS in any vertebrate cell type. Finally, liquid chromatography and mass spectrometry (LC-MS/MS) analysis of atNHE1 immunoprecipitated from atRBC membranes reveals 9 phosphorylated serine/threonine residues, suggesting that activation of atNHE1 involves multiple phosphorylation and/or dephosphorylation events.
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21
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El Idrissi K, Eddarir S, Tokarski C, Rolando C. Immobilized metal affinity chromatography using open tubular capillary for phosphoprotein analysis: Comparison between polymer brush coating and surface functionalization. J Chromatogr B Analyt Technol Biomed Life Sci 2011; 879:2852-9. [DOI: 10.1016/j.jchromb.2011.08.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2011] [Revised: 08/02/2011] [Accepted: 08/04/2011] [Indexed: 11/27/2022]
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22
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Zhang L, Wang H, Liang Z, Yang K, Zhang L, Zhang Y. Facile preparation of monolithic immobilized metal affinity chromatography capillary columns for selective enrichment of phosphopeptides. J Sep Sci 2011; 34:2122-30. [DOI: 10.1002/jssc.201100169] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Revised: 04/09/2011] [Accepted: 04/11/2011] [Indexed: 01/23/2023]
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23
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Eyrich B, Sickmann A, Zahedi RP. Catch me if you can: mass spectrometry-based phosphoproteomics and quantification strategies. Proteomics 2011; 11:554-70. [PMID: 21226000 DOI: 10.1002/pmic.201000489] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2010] [Revised: 09/13/2010] [Accepted: 09/21/2010] [Indexed: 01/16/2023]
Abstract
Phosphorylation of proteins is one of the most prominent PTMs and for instance a key regulator of signal transduction. In order to improve our understanding of cellular phosphorylation events, considerable effort has been devoted to improving the analysis of phosphorylation by MS-based proteomics. Different enrichment strategies for phosphorylated peptides/proteins, such as immunoaffinity chromatography (IMAC) or titanium dioxide, have been established and constantly optimized for subsequent MS analysis. Concurrently, specific MS techniques were developed for more confident identification and phosphorylation site localization. In addition, more attention is paid to the LC-MS instrumentation to avoid premature loss of phosphorylated peptides within the analytical system. Despite major advances in all of these fields, the analysis of phosphopeptides still remains far from being routine in proteomics. However, to reveal cellular regulation by phosphorylation events, not only qualitative information about the phosphorylation status of proteins but also, in particular, quantitative information about distinct changes in phosphorylation patterns upon specific stimulation is mandatory. Thus, yielded insights are of outstanding importance for the emerging field of systems biology. In this review, we will give an insight into the historical development of phosphoproteome analysis and discuss its recent progress particularly regarding phosphopeptide quantification and assessment of phosphorylation stoichiometry.
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Affiliation(s)
- Beate Eyrich
- Leibniz-Institut für Analytische Wissenschaften-ISAS-eV, Dortmund, Germany
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24
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Hou C, Ma J, Tao D, Shan Y, Liang Z, Zhang L, Zhang Y. Organic−Inorganic Hybrid Silica Monolith Based Immobilized Titanium Ion Affinity Chromatography Column for Analysis of Mitochondrial Phosphoproteome. J Proteome Res 2010; 9:4093-101. [DOI: 10.1021/pr100294z] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Chunyan Hou
- Key Laboratory of Separation Science for Analytical Chemistry, National Chromatographic Research and Analysis Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China, and Graduate School of the Chinese Academy of Sciences, Beijing 100039, China
| | - Junfeng Ma
- Key Laboratory of Separation Science for Analytical Chemistry, National Chromatographic Research and Analysis Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China, and Graduate School of the Chinese Academy of Sciences, Beijing 100039, China
| | - Dingyin Tao
- Key Laboratory of Separation Science for Analytical Chemistry, National Chromatographic Research and Analysis Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China, and Graduate School of the Chinese Academy of Sciences, Beijing 100039, China
| | - Yichu Shan
- Key Laboratory of Separation Science for Analytical Chemistry, National Chromatographic Research and Analysis Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China, and Graduate School of the Chinese Academy of Sciences, Beijing 100039, China
| | - Zhen Liang
- Key Laboratory of Separation Science for Analytical Chemistry, National Chromatographic Research and Analysis Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China, and Graduate School of the Chinese Academy of Sciences, Beijing 100039, China
| | - Lihua Zhang
- Key Laboratory of Separation Science for Analytical Chemistry, National Chromatographic Research and Analysis Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China, and Graduate School of the Chinese Academy of Sciences, Beijing 100039, China
| | - Yukui Zhang
- Key Laboratory of Separation Science for Analytical Chemistry, National Chromatographic Research and Analysis Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China, and Graduate School of the Chinese Academy of Sciences, Beijing 100039, China
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25
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Kumazawa T, Hasegawa C, Lee XP, Sato K. New and unique methods of solid-phase extraction for use before instrumental analysis of xenobiotics in human specimens. Forensic Toxicol 2010. [DOI: 10.1007/s11419-010-0097-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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26
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The use of liquid phase deposition prepared phosphonate grafted silica nanoparticle-deposited capillaries in the enrichment of phosphopeptides. J Sep Sci 2010; 33:1806-15. [DOI: 10.1002/jssc.201000029] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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27
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Yang C, Wang S, Chang C, Wang Y, Hu X. Capillary Isoelectric Focusing with an Open Tubular Immobilized pH Gradient. Anal Chem 2010; 82:1580-3. [DOI: 10.1021/ac902223y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Chun Yang
- College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China
| | - Shuangshou Wang
- College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China
| | - Chunyan Chang
- College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China
| | - Yang Wang
- College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China
| | - Xiaoya Hu
- College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China
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28
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Kim JS, Cui E, Kim HJ. Picolinamidination of phosphopeptides for MALDI-TOF-TOF mass spectrometric sequencing with enhanced sensitivity. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2009; 20:1751-1758. [PMID: 19586781 DOI: 10.1016/j.jasms.2009.05.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2009] [Revised: 05/25/2009] [Accepted: 05/26/2009] [Indexed: 05/28/2023]
Abstract
Two orders of magnitude matrix-assisted laser desorption/ionization (MALDI) signal enhancement of phosphopeptides has been achieved by picolinamidination of N-terminal amine group and epsilon-amine group of lysine residues. Due to the presence of picolinamidination tag at the N-terminal amine of peptides, MS/MS spectra with a strong b-ion series was obtained, which greatly facilitated sequencing and identification of the phosphorylation site. Phosphorylation site of a phosphopeptide could be identified from MALDI TOF/TOF spectrum obtained from a tryptic or a chymotryptic phosphopeptide, which was not even detected in the positive ion mode, without signal enhancement by picolinamidination, due to the negative charge of the phosphate group in the presence of other peptides.
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Affiliation(s)
- Jong-Seo Kim
- Department of Chemistry, Seoul National University, Seoul, Korea
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29
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Coccaro E, Karki P, Cojocaru C, Fliegel L. Phenylephrine and sustained acidosis activate the neonatal rat cardiomyocyte Na+/H+ exchanger through phosphorylation of amino acids Ser770 and Ser771. Am J Physiol Heart Circ Physiol 2009; 297:H846-58. [PMID: 19542484 DOI: 10.1152/ajpheart.01231.2008] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The mammalian Na(+)/H(+) exchanger isoform 1 (NHE1) is a ubiquitously expressed membrane protein that regulates intracellular pH in the myocardium. NHE1 is also important in mediating myocardial hypertrophy, and the blockage of NHE1 activity prevents hypertrophy and reduces ischemia-reperfusion injury in animal models. We recently demonstrated that extracellular-regulated kinase (ERK)-mediated activation of NHE1 occurs during ischemia-reperfusion of the myocardium. To understand the regulation of NHE1 in the myocardium by phosphorylation, we expressed a series of adenoviruses that express wild-type and mutant cDNA for NHE1. All exogenous cDNA for NHE1 had additional mutations [Leu(163)Phe/Gly(174)Ser], which increases NHE1 resistance to EMD-87580 (a specific blocker of NHE1) 100-fold, and allowed the measurement of exogenous NHE1 while inhibiting endogenous NHE1. By examining the effects of a series of mutations of the NHE1 cytosolic region, we determined that the amino acids Ser(770) and Ser(771) were essential for the acute activation of NHE1 activity in rat cardiomyocytes. The specific mutation of either residue prevented the rapid activation of exchanger activity by a sustained intracellular acidosis through ERK-dependent pathways. The same amino acids were critical to phenylephrine-mediated, ERK-dependent activation of NHE1 activity and increased the phosphorylation in intact rat cardiomyocytes. The results demonstrate that both sustained intracellular acidosis and phenylephrine rapidly activate the NHE1 protein in intact cardiac cells through ERK-dependent pathways that act on a common pathway mediated by amino acids Ser(770) and Ser(771) of the cytosolic tail of the protein.
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Affiliation(s)
- Ersilia Coccaro
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
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30
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Xue Y, Wei J, Han H, Zhao L, Cao D, Wang J, Yang X, Zhang Y, Qian X. Application of open tubular capillary columns coated with zirconium phosphonate for enrichment of phosphopeptides. J Chromatogr B Analyt Technol Biomed Life Sci 2009; 877:757-64. [DOI: 10.1016/j.jchromb.2009.02.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2008] [Revised: 02/05/2009] [Accepted: 02/05/2009] [Indexed: 11/17/2022]
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31
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Fliegel L. Regulation of the Na+/H+exchanger in the healthy and diseased myocardium. Expert Opin Ther Targets 2008; 13:55-68. [PMID: 19063706 DOI: 10.1517/14728220802600707] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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32
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Pyatkivskyy Y, Ryzhov V. Coupling of ion-molecule reactions with liquid chromatography on a quadrupole ion trap mass spectrometer. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2008; 22:1288-1294. [PMID: 18351715 DOI: 10.1002/rcm.3494] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We report for the first time a coupling of gas-phase ion-molecule reactions with chromatographic separations on a quadrupole ion trap mass spectrometer. The interface was accomplished by using a pulsed valve for the introduction of a volatile neutral into the ion trap. The pulsed valve controller is synchronized with the mass spectrometer software. The setup requires some minor modifications to the vacuum system of the commercial quadrupole ion trap but most of the modifications are external to the mass spectrometer. Two applications of this interface are described: differentiation between two phosphoglucose positional isomers and detection of a phosphopeptide in a peptide mixture. Both applications are using the reactivity of trimethoxyborate towards a phosphate moiety in the negative ion mode. The detection of phosphopeptides hinges on our findings that non-phosphorylated peptide anions do not react with trimethoxyborate. This LC/MS detection can be easily visualized in terms of selected reaction monitoring.
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Affiliation(s)
- Yuriy Pyatkivskyy
- Department of Chemistry and Biochemistry, Northern Illinois University, DeKalb, IL 60115, USA
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33
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Wang H, Duan J, Zhang L, Liang Z, Zhang W, Zhang Y. Characterization of multi-phosphopeptides by μHPLC–ESI-MS/MS with alkaline phosphatase treatment. J Sep Sci 2008; 31:480-7. [DOI: 10.1002/jssc.200700445] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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34
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Li Y, Wu J, Qi D, Xu X, Deng C, Yang P, Zhang X. Novel approach for the synthesis of Fe3O4@TiO2core–shell microspheres and their application to the highly specific capture of phosphopeptides for MALDI-TOF MS analysis. Chem Commun (Camb) 2008:564-6. [DOI: 10.1039/b716055k] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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35
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Yu LR, Issaq HJ, Veenstra TD. Phosphoproteomics for the discovery of kinases as cancer biomarkers and drug targets. Proteomics Clin Appl 2007; 1:1042-57. [DOI: 10.1002/prca.200700102] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2007] [Indexed: 12/31/2022]
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36
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Malo ME, Fliegel L. Physiological role and regulation of the Na+/H+ exchanger. Can J Physiol Pharmacol 2007; 84:1081-95. [PMID: 17218973 DOI: 10.1139/y06-065] [Citation(s) in RCA: 167] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In mammalian eukaryotic cells, the Na+/H+ exchanger is a family of membrane proteins that regulates ions fluxes across membranes. Plasma membrane isoforms of this protein extrude 1 intracellular proton in exchange for 1 extracellular sodium. The family of Na+/H+ exchangers (NHEs) consists of 9 known isoforms, NHE1-NHE9. The NHE1 isoform was the first discovered, is the best characterized, and exists on the plasma membrane of all mammalian cells. It contains an N-terminal 500 amino acid membrane domain that transports ions, plus a 315 amino acid C-terminal, the intracellular regulatory domain. The Na+/H+ exchanger is regulated by both post-translational modifications including protein kinase-mediated phosphorylation, plus by a number of regulatory-binding proteins including phosphatidylinositol-4,5-bisphosphate, calcineurin homologous protein, ezrin, radixin and moesin, calmodulin, carbonic anhydrase II, and tescalcin. The Na+/H+ exchanger is involved in a variety of complex physiological and pathological events that include regulation of intracellular pH, cell movement, heart disease, and cancer. This review summarizes recent advances in the understanding of the physiological role and regulation of this protein.
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Affiliation(s)
- Mackenzie E Malo
- Department of Biochemistry, 347 Medical Science Building, University of Alberta, Edmonton, AB T6G 2H7, Canada
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37
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Imanishi SY, Kochin V, Eriksson JE. Optimization of phosphopeptide elution conditions in immobilized Fe(III) affinity chromatography. Proteomics 2007; 7:174-6. [PMID: 17152096 DOI: 10.1002/pmic.200600571] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
While immobilized metal affinity chromatography (IMAC) has been widely used for affinity purification of phosphopeptides, the technique suffers from insufficient specificity. Therefore, there is an urgent need for IMAC optimization to yield the selectivity and sensitivity that is required for more challenging analyses. Recently, 2,5-dihydroxybenzoic acid (DHB) and phosphoric acid mixture has been reported as an efficient IMAC eluant. The disadvantage of DHB is that is not suitable for electrospray ionization-mass spectrometry. While further developing the IMAC elution protocol to overcome this problem, we noticed that DHB is not necessary and found a novel combination of phosphoric acid and acetonitrile to be more efficient. The purification efficacy of the novel protocol is superior to all previously described methods, while still being compatible with the most commonly used mass-spectrometric techniques in phosphoproteomics.
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Affiliation(s)
- Susumu Y Imanishi
- Turku Centre for Biotechnology, University of Turku and Abo Akademi University, Turku, Finland
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38
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Feng S, Pan C, Jiang X, Xu S, Zhou H, Ye M, Zou H. Fe3+ immobilized metal affinity chromatography with silica monolithic capillary column for phosphoproteome analysis. Proteomics 2007; 7:351-60. [PMID: 17177250 DOI: 10.1002/pmic.200600045] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Immobilized metal affinity chromatography (IMAC) is a commonly used technique for phosphoproteome analysis due to its high affinity for adsorption of phosphopeptides. Miniaturization of IMAC column is essential for the analysis of a small amount of sample. Nanoscale IMAC column was prepared by chemical modification of silica monolith with iminodiacetic acid (IDA) followed by the immobilization of Fe3+ ion inside the capillary. It was demonstrated that Fe3+-IDA silica monolithic IMAC capillary column could specifically capture the phosphopeptides from tryptic digest of alpha-casein with analysis by MALDI-TOF MS. The silica monolithic IMAC capillary column was manually coupled with nanoflow RPLC/nanospray ESI mass spectrometer (muRPLC-nanoESI MS) for phosphoproteome analysis. The system was validated by analysis of standard phosphoproteins and then it was applied to the analysis of protein phosphorylation in mouse liver lysate. Besides MS/MS spectra, MS/MS/MS spectra were also collected for neutral loss peak. After database search and manual validation with conservative criteria, 29 singly phosphorylated peptides were identified by analyzing a tryptic digest of only 12 mug mouse liver lysate. The results demonstrated that the silica monolithic IMAC capillary column coupled with muRPLC-nanoESI MS was very suitable for the phosphoproteome analysis of minute sample.
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Affiliation(s)
- Shun Feng
- National Chromatographic R&A Center, Dalian Institute of Chemical Physics, The Chinese Academy of Sciences, Dalian, China
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39
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Malo ME, Li L, Fliegel L. Mitogen-activated protein kinase-dependent activation of the Na+/H+ exchanger is mediated through phosphorylation of amino acids Ser770 and Ser771. J Biol Chem 2007; 282:6292-9. [PMID: 17209041 DOI: 10.1074/jbc.m611073200] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
We investigated regulation of the type 1 isoform of the Na(+)/H(+) exchanger by phosphorylation. Four specific groups of serine and threonine residues in the regulatory carboxyl-terminal tail were mutated to alanine residues: group 1, S693A; group 2, T718A and S723A/S726A/S729A; group 3, S766A/S770A/S771A; and group 4, T779A and S785A. The proteins were expressed in Na(+)/H(+) exchanger-deficient cells, and the activity was characterized. All of the mutants had proper expression, localization, and normal basal activity relative to wild type NHE1. Sustained intracellular acidosis was used to activate NHE1 via an ERK-dependent pathway that could be blocked with the MEK inhibitor U0126. Immunoprecipitation of (32)P-labeled Na(+)/H(+) exchanger from intact cells showed that sustained intracellular acidosis increased Na(+)/H(+) exchanger phosphorylation in vivo. This was blocked by U0126. The Na(+)/H(+) exchanger activity of mutants 1 and 2 was stimulated similar to wild type Na(+)/H(+) exchanger. Mutant 4 showed a partially reduced level of activation. However, mutant 3 was not stimulated by sustained intracellular acidosis, and loss of stimulation of activity correlated to a loss of sustained acidosis-mediated phosphorylation in vivo. Mutation of the individual amino acids within mutant 3, Ser(766), Ser(770), and Ser(771), showed that Ser(770) and Ser(771) are responsible for mediating increases in NHE1 activity through sustained acidosis. Both intact Ser(770) and Ser(771) were required for sustained acidosis-mediated activation of NHE1. Our results suggest that amino acids Ser(770) and Ser(771) mediate ERK-dependent activation of the Na(+)/H(+) exchanger in vivo.
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Affiliation(s)
- Mackenzie E Malo
- Department of Biochemistr, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
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40
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Lee J, Xu Y, Chen Y, Sprung R, Kim SC, Xie S, Zhao Y. Mitochondrial phosphoproteome revealed by an improved IMAC method and MS/MS/MS. Mol Cell Proteomics 2007; 6:669-76. [PMID: 17208939 PMCID: PMC2902983 DOI: 10.1074/mcp.m600218-mcp200] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
IMAC in combination with mass spectrometry is a promising approach for global analysis of protein phosphorylation. Nevertheless this approach suffers from two shortcomings: inadequate efficiency of IMAC and poor fragmentation of phosphopeptides in the mass spectrometer. Here we report optimization of the IMAC procedure using (32)P-labeled tryptic peptides and development of MS/MS/MS (MS3) for identifying phosphopeptide sequences and phosphorylation sites. The improved IMAC method allowed recovery of phosphorylated tryptic peptides up to approximately 77% with only minor retention of unphosphorylated peptides. MS3 led to efficient fragmentation of the peptide backbone in phosphopeptides for sequence assignment. Proteomics of mitochondrial phosphoproteins using the resulting IMAC protocol and MS3 revealed 84 phosphorylation sites in 62 proteins, most of which have not been reported before. These results revealed diverse phosphorylation pathways involved in the regulation of mitochondrial functions. Integration of the optimized batchwise IMAC protocol with MS3 offers a relatively simple and more efficient approach for proteomics of protein phosphorylation.
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Affiliation(s)
| | | | | | | | | | | | - Yingming Zhao
- To whom correspondence should be addressed. Tel.: 214-648-7947; Fax: 214-648-2797;
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41
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Ross ARS. Identification of histidine phosphorylations in proteins using mass spectrometry and affinity-based techniques. Methods Enzymol 2007; 423:549-72. [PMID: 17609151 DOI: 10.1016/s0076-6879(07)23027-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Histidine phosphorylation plays a key role in prokaryotic signaling and accounts for approximately 6% of the protein phosphorylation events in eukaryotics. Phosphohistidines generally act as intermediates in the transfer of phosphate groups from donor to acceptor molecules. Examples include the bacterial phosphoenolpyruvate:sugar phosphotransferase system (PTS) and the histidine kinases found in two-component signal transduction pathways. The latter are utilized by bacteria and plants to sense and adapt to changing environmental conditions. Despite the importance of histidine phosphorylation in two-component signaling systems, relatively few proteins have so far been identified as containing phosphorylated histidine residues. This is largely due to the instability of phosphohistidines, which, unlike the phosphoesters formed by serine, threonine, and tyrosine, are labile and susceptible to acid hydrolysis. Nevertheless, it is possible to preserve and identify phosphorylated histidine residues in target proteins using appropriate sample preparation, affinity purification, and mass spectrometric techniques. This chapter provides a brief overview of such techniques, describes their use in confirming histidine phosphorylation of a known PTS protein (HPr), and suggests how this approach might be adapted for large-scale identification of histidine-phosphorylated proteins in two-component systems.
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Affiliation(s)
- Andrew R S Ross
- Plant biotechnology Institute, National Research Council of Canada, Saskatoon, Saskatchewan, Canada
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Tan F, Zhang Y, Wang J, Wei J, Qin P, Cai Y, Qian X. Specific capture of phosphopeptides on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry targets modified by magnetic affinity nanoparticles. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2007; 21:2407-14. [PMID: 17582624 DOI: 10.1002/rcm.3100] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Specific capture of phosphopeptides from protein digests is a critical step for identification of phosphoproteins by mass spectrometry. In this study, we report a novel phosphopeptide-capture approach based on the specific interaction of phosphopeptides with a stainless steel target modified with magnetic affinity nanoparticles. The modification which was carried out by loading the suspension of nanoparticles into sample wells of the target did not require any pretreatment procedure to the target and did not involve chemical binding reactions. To isolate phosphopeptides, digests were loaded into the wells of the modified target for 10 min incubation, followed by rinsing with washing buffer to remove unbound species; matrix was then added to the captured phosphopeptides prior to analysis by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS). Capturing the phosphopeptides on the modified target simplified significantly analytical operations and reduced sample loss. This approach has been applied to solution digests of alpha-casein, beta-casein, and a mixture of five proteins; a number of phosphopeptides were confidently detected. Phosphopeptides from digests of 10 fmol beta-casein could be isolated and detected by MALDI-TOFMS with this method. In addition, this approach has been applied successfully to the isolation of phosphopeptides from in-gel digestive products of sub-pmol phosphoproteins after separation by sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS-PAGE).
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Affiliation(s)
- Feng Tan
- State Key Laboratory of Proteomics-Beijing Proteome Research Center, 33 Life Park Road, Zhongguancun, Beijing 102206, China
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Morandell S, Stasyk T, Grosstessner-Hain K, Roitinger E, Mechtler K, Bonn GK, Huber LA. Phosphoproteomics strategies for the functional analysis of signal transduction. Proteomics 2006; 6:4047-56. [PMID: 16791829 DOI: 10.1002/pmic.200600058] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Protein phosphorylation is a key regulatory mechanism of cellular signalling processes. The analysis of phosphorylated proteins and the characterisation of phosphorylation sites under different biological conditions are some of the most challenging tasks in current proteomics research. Reduction of the sample complexity is one major step for the analysis of low-abundance kinase substrates, which can be achieved by various subcellular fractionation techniques. One strategy is the enrichment of phosphorylated proteins or peptides by immunoprecipitation or chromatography, e.g. immobilised metal affinity chromatography, prior to analysis. 2-DE gels are powerful tools for the analysis of phosphoproteins when combined with new multiplexing techniques like DIGE, phosphospecific stains, autoradiography or immunoblotting. In addition, several gel-free methods combining chromatography with highly sensitive MS have been successfully applied for the analysis of complex phosphoproteomes. Recently developed approaches like KESTREL or 'chemical genetics' and also protein microarrays offer new possibilities for the identification of specific kinase targets. This review summarises various strategies for the analyses of phosphoproteins with a special focus on the identification of novel kinase substrates.
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Affiliation(s)
- Sandra Morandell
- Division Cell Biology, Biocenter, Innsbruck Medical University, Innsbruck, Austria
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Xu S, Zhou H, Pan C, Fu Y, Zhang Y, Li X, Ye M, Zou H. Iminodiacetic acid derivatized porous silicon as a matrix support for sample pretreatment and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2006; 20:1769-75. [PMID: 16676319 DOI: 10.1002/rcm.2493] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Iminodiacetic acid (IDA)-1,2-epoxy-9-decene has been synthesized and covalently linked to the surface of porous silicon wafer through a photochemical reaction. The negatively charged carboxylic acid groups on the porous silicon wafer are capable of binding oppositely charged species from sample solutions through electrostatic interactions. This allows the removal of contaminants prior to matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) by simply washing the porous silicon surface. The carboxylic acid end groups on porous silicon can be used to selectively bind and concentrate target species in sample solutions. Furthermore, Fe(3+)-IDA-derivatized porous silicon was prepared to specifically and effectively concentrate phosphopeptides from the tryptic digests of phosphoproteins, followed by MALDI-MS analysis.
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Affiliation(s)
- Songyun Xu
- National Chromatographic R & A Center, Dalian Institute of Chemical Physics, The Graduate School of Chinese Academy of Sciences, Chinese Academy of Sciences, Dalian 116011, China
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Zheng Y, Liu H, Coughlin J, Zheng J, Li L, Stone JC. Phosphorylation of RasGRP3 on threonine 133 provides a mechanistic link between PKC and Ras signaling systems in B cells. Blood 2005; 105:3648-54. [PMID: 15657177 DOI: 10.1182/blood-2004-10-3916] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
B-cell receptor (BCR) signaling activates a number of intracellular signaling molecules including phospholipase C-gamma2 (PLC-gamma2), which generates membrane diacylglycerol (DAG). DAG recruits both protein kinase C (PKC) and RasGRP family members to the membrane and contributes to their activation. We have hypothesized that membrane colocalization facilitates activation of RasGRP3 by PKC. Here we demonstrate that PKC phosphorylates RasGRP3 on Thr133 in vitro, as determined by mass spectrometry. RasGRP3 with a Thr133Ala substitution is a poor PKC substrate in vitro and a poor Ras activator in vivo. Antiphosphopeptide antibodies recognize Thr133-phosphorylated RasGRP3 in B cells after BCR stimulation or DAG analog treatment, but much less so in resting cells. PKC inhibitors block RasGRP3 Thr133 phosphorylation and Ras-extracellular signal-related kinase (Erk) signaling with a similar pattern. After stimulation of T-cell receptor (TCR) or DAG analog treatment of T cells, PKC-catalyzed phosphorylation of RasGRP1 occurs on the homologous residue, Thr184. These studies shed light on the proposed "PKC-Ras pathway" and support the hypothesis that RasGRP phosphorylation by PKC is a mechanism that integrates DAG signaling systems in T and B cells. PKC-mediated regulation of RasGRPs in lymphocytes may generate cooperative signaling in response to increases in DAG. The mast- and myeloid-selective family member RasGRP4 is regulated by different means.
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Affiliation(s)
- Yong Zheng
- Department of Biochemistry, University of Alberta, Edmonton AB, Canada
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Schlosser G, Vékey K, Malorni A, Pocsfalvi G. Combination of solid-phase affinity capture on magnetic beads and mass spectrometry to study non-covalent interactions: example of minor groove binding drugs. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2005; 19:3307-14. [PMID: 16217838 DOI: 10.1002/rcm.2193] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
A simple and novel approach was developed to detect non-covalent interactions. It is based on combination of solid-phase affinity capture with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS). One of the interacting molecules is bound to magnetic beads and is incubated with the target molecules in solution. The complex bound on the solid support is removed from the solution and transferred for MALDI analysis. Mass spectrometry is used only to detect the target compound, which is far more straightforward than detecting the intact non-covalent complex. To demonstrate the applicability of the method, an AT-rich oligonucleotide (5'-CCCCCAATTCCCCC-3') and its complementary biotinylated sequence (5'-biotin-GGGGGAATTGGGGG-3') were hybridized and immobilized to paramagnetic particles by streptavidin-biotin interaction. The immobilized duplex oligonucleotide was reacted with minor groove binding drugs, Netropsin, Distamycin A, Hoechst 33258 and 4',6-diamidino-2-phenylindole. The resulting DNA-drug complex bound to the particles was separated and analyzed by linear MALDI-TOFMS after washing. Drugs were selectively detected in the spectra. Relative binding strengths were also estimated using competitive complexation.
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Affiliation(s)
- Gitta Schlosser
- Proteomic and Biomolecular Mass Spectrometry Center (CeSMa-ProBio), Institute of Food Science and Technology, C.N.R., via Roma 52 a/c, 83100 Avellino, Italy
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Hur EH, Hur W, Choi JY, Kim IK, Kim HY, Yoon SK, Rhim H. Functional identification of the pro-apoptotic effector domain in human Sox4. Biochem Biophys Res Commun 2004; 325:59-67. [PMID: 15522200 DOI: 10.1016/j.bbrc.2004.09.215] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2004] [Indexed: 11/22/2022]
Abstract
Recent studies provide evidence that Sox4 is involved in regulating apoptosis as well as tumorigenesis of various human cancers; however, its role in the apoptotic machinery is not fully understood. Here we describe that the central domain containing glycine-rich region in Sox4, named CD, is a pivotal pro-apoptotic domain to induce apoptotic cell death. Deletion of the DNA-binding domain or trans-activation domain in Sox4 did not significantly affect pro-apoptotic activity, whereas transient transfection of the high mobility group box or the serine-rich region abrogated the apoptotic activity. Moreover, overexpression of the CD construct (aa 166-342) revealed the apoptotic activity comparable to that of wild-type Sox4, approximately 60% of cell death. Our data suggest that the apoptotic activity of Sox4 can be dissociated from its transcriptional trans-activation and is mediated through its CD.
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Affiliation(s)
- Eun-Hye Hur
- Research Institute of Molecular Genetics, Catholic Research Institutes of Medical Sciences, College of Medicine, The Catholic University of Korea, Seoul 137-701, Republic of Korea
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Abstract
The recent development of mass spectrometry, i.e., high sensitivity, automation of protein identification and some post-translational modifications (PTMs) significantly increased the number of large-scale proteomics projects. However, there are still considerable limitations as none of the currently available proteomics techniques allows the analysis of an entire proteome in a single step procedure. On the other hand, there are several successful studies analyzing well defined groups of proteins, e.g., proteins of purified organelles, membrane microdomains or isolated proteins with certain PTMs. Coupling of advanced separation methodologies (different prefractionation strategies, such as subcellular fractionation, affinity purification, fractionation of proteins and peptides according to their physicochemical properties) to highly sensitive mass spectrometers provides powerful means to detect and analyze dynamic changes of low abundant regulatory proteins in eukaryotic cells on the subcellular level. This review summarizes and discusses recent strategies in proteomics approaches where different fractionation strategies were successfully applied.
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Affiliation(s)
- Taras Stasyk
- Department of Histology and Molecular Cell Biology, Medical University of Innsbruck, Austria
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Fliegel L, Karmazyn M. The cardiac Na-H exchanger: a key downstream mediator for the cellular hypertrophic effects of paracrine, autocrine and hormonal factors. Biochem Cell Biol 2004; 82:626-35. [PMID: 15674430 DOI: 10.1139/o04-129] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The major mechanism by which the heart cell regulates intracellular pH is the Na+H+exchanger (NHE) with the NHE-1 isoform as the primary cardiac subtype. Although NHE-1 has been implicated in mediating ischemic injury, more recent evidence implicates the antiporter as a key mediator of hypertrophy, which is produced by various autocrine, paracrine and hormonal factors such as endothelin-1, angiotensin II, and α1adrenoceptor agonists. These agonists activate the antiporter via phosphorylation-dependent processes. NHE-1 inhibition is likely conducive to attenuating the remodelling process after myocardial infarction. These effects probably occur independently of infarct size reduction and involve attenuation of subsequent postinfarction heart failure. As such, inhibitors of NHE offer substantial promise for clinical development that will attenuate acute responses to myocardial postinfarction and chronic pos t infarction, which evolve toward heart failure. The regulation of NHE-1 is discussed as is its potential role in mediating cardiomyocyte hypertrophy.Key words: NHE-1, cardiac hypertrophy, heart failure, myocardial remodelling.
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Affiliation(s)
- Larry Fliegel
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
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