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Torres Robles J, Lou HJ, Shi G, Pan PL, Turk BE. Linear motif specificity in signaling through p38α and ERK2 mitogen-activated protein kinases. Proc Natl Acad Sci U S A 2023; 120:e2316599120. [PMID: 37988460 PMCID: PMC10691213 DOI: 10.1073/pnas.2316599120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 10/26/2023] [Indexed: 11/23/2023] Open
Abstract
Mitogen-activated protein kinase (MAPK) cascades are essential for eukaryotic cells to integrate and respond to diverse stimuli. Maintaining specificity in signaling through MAPK networks is key to coupling distinct inputs to appropriate cellular responses. Docking sites-short linear motifs found in MAPK substrates, regulators, and scaffolds-can promote signaling specificity through selective interactions, but how they do so remains unresolved. Here, we screened a proteomic library for sequences interacting with the MAPKs extracellular signal-regulated kinase 2 (ERK2) and p38α, identifying selective and promiscuous docking motifs. Sequences specific for p38α had high net charge and lysine content, and selective binding depended on a pair of acidic residues unique to the p38α docking interface. Finally, we validated a set of full-length proteins harboring docking sites selected in our screens to be authentic MAPK interactors and substrates. This study identifies features that help define MAPK signaling networks and explains how specific docking motifs promote signaling integrity.
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Affiliation(s)
- Jaylissa Torres Robles
- Department of Chemistry, Yale University, New Haven, CT06520
- Department of Pharmacology, Yale School of Medicine, New Haven, CT06520
| | - Hua Jane Lou
- Department of Pharmacology, Yale School of Medicine, New Haven, CT06520
| | - Guangda Shi
- Department of Pharmacology, Yale School of Medicine, New Haven, CT06520
| | | | - Benjamin E. Turk
- Department of Pharmacology, Yale School of Medicine, New Haven, CT06520
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2
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Bardwell L, Thorner J. Mitogen-activated protein kinase (MAPK) cascades-A yeast perspective. Enzymes 2023; 54:137-170. [PMID: 37945169 DOI: 10.1016/bs.enz.2023.07.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2023]
Abstract
Discovery of the class of protein kinase now dubbed a mitogen (or messenger)-activated protein kinase (MAPK) is an illustrative example of how disparate lines of investigation can converge and reveal an enzyme family universally conserved among eukaryotes, from single-celled microbes to humans. Moreover, elucidation of the circuitry controlling MAPK function defined a now overarching principle in enzyme regulation-the concept of an activation cascade mediated by sequential phosphorylation events. Particularly ground-breaking for this field of exploration were the contributions of genetic approaches conducted using several model organisms, but especially the budding yeast Saccharomyces cerevisiae. Notably, examination of how haploid yeast cells respond to their secreted peptide mating pheromones was crucial in pinpointing genes encoding MAPKs and their upstream activators. Fully contemporaneous biochemical analysis of the activities elicited upon stimulation of mammalian cells by insulin and other growth- and differentiation-inducing factors lead eventually to the demonstration that components homologous to those in yeast were involved. Continued studies of these pathways in yeast were integral to other foundational discoveries in MAPK signaling, including the roles of tethering, scaffolding and docking interactions.
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Affiliation(s)
- Lee Bardwell
- Department of Developmental and Cell Biology, School of Biological Sciences, University of California, Irvine, Irvine, CA, United States
| | - Jeremy Thorner
- Division of Biochemistry, Biophysics and Structural Biology, Department of Molecular and Cell Biology, College of Letters and Science, University of California, Berkeley, Berkeley, CA, United States.
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3
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O’Shaughnessy WJ, Dewangan PS, Paiz EA, Reese ML. Not your Mother's MAPKs: Apicomplexan MAPK function in daughter cell budding. PLoS Pathog 2022; 18:e1010849. [PMID: 36227859 PMCID: PMC9560070 DOI: 10.1371/journal.ppat.1010849] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Reversible phosphorylation by protein kinases is one of the core mechanisms by which biological signals are propagated and processed. Mitogen-activated protein kinases, or MAPKs, are conserved throughout eukaryotes where they regulate cell cycle, development, and stress response. Here, we review advances in our understanding of the function and biochemistry of MAPK signaling in apicomplexan parasites. As expected for well-conserved signaling modules, MAPKs have been found to have multiple essential roles regulating both Toxoplasma tachyzoite replication and sexual differentiation in Plasmodium. However, apicomplexan MAPK signaling is notable for the lack of the canonical kinase cascade that normally regulates the networks, and therefore must be regulated by a distinct mechanism. We highlight what few regulatory relationships have been established to date, and discuss the challenges to the field in elucidating the complete MAPK signaling networks in these parasites.
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Affiliation(s)
- William J. O’Shaughnessy
- Department of Pharmacology, University of Texas, Southwestern Medical Center, Dallas, Texas, United States of America
| | - Pravin S. Dewangan
- Department of Pharmacology, University of Texas, Southwestern Medical Center, Dallas, Texas, United States of America
| | - E. Ariana Paiz
- Department of Pharmacology, University of Texas, Southwestern Medical Center, Dallas, Texas, United States of America
| | - Michael L. Reese
- Department of Pharmacology, University of Texas, Southwestern Medical Center, Dallas, Texas, United States of America,Department of Biochemistry, University of Texas, Southwestern Medical Center, Dallas, Texas, United States of America,* E-mail:
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4
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Kliche J, Ivarsson Y. Orchestrating serine/threonine phosphorylation and elucidating downstream effects by short linear motifs. Biochem J 2022; 479:1-22. [PMID: 34989786 PMCID: PMC8786283 DOI: 10.1042/bcj20200714] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 12/16/2021] [Accepted: 12/20/2021] [Indexed: 12/13/2022]
Abstract
Cellular function is based on protein-protein interactions. A large proportion of these interactions involves the binding of short linear motifs (SLiMs) by folded globular domains. These interactions are regulated by post-translational modifications, such as phosphorylation, that create and break motif binding sites or tune the affinity of the interactions. In addition, motif-based interactions are involved in targeting serine/threonine kinases and phosphatases to their substrate and contribute to the specificity of the enzymatic actions regulating which sites are phosphorylated. Here, we review how SLiM-based interactions assist in determining the specificity of serine/threonine kinases and phosphatases, and how phosphorylation, in turn, affects motif-based interactions. We provide examples of SLiM-based interactions that are turned on/off, or are tuned by serine/threonine phosphorylation and exemplify how this affects SLiM-based protein complex formation.
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Affiliation(s)
- Johanna Kliche
- Department of Chemistry – BMC, Uppsala University, Husargatan 3, Box 576 751 23 Uppsala, Sweden
| | - Ylva Ivarsson
- Department of Chemistry – BMC, Uppsala University, Husargatan 3, Box 576 751 23 Uppsala, Sweden
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5
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Alexa A, Ember O, Szabó I, Mo'ath Y, Póti ÁL, Reményi A, Bánóczi Z. Peptide Based Inhibitors of Protein Binding to the Mitogen-Activated Protein Kinase Docking Groove. Front Mol Biosci 2021; 8:690429. [PMID: 34277705 PMCID: PMC8281026 DOI: 10.3389/fmolb.2021.690429] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 06/18/2021] [Indexed: 11/21/2022] Open
Abstract
Mitogen-activated protein kinases (MAPK) are important regulatory units in cells and they take part in the regulation of many cellular functions such as cell division, differentiation or apoptosis. All MAPKs have a shallow docking groove that interacts with linear binding motifs of their substrate proteins and their regulatory proteins such as kinases, phosphatases, scaffolds. Inhibition of these protein–protein interactions may reduce or abolish the activity of the targeted kinase. Based on the wide range of their biological activity, this kind of inhibition can be useful in the treatment of many disorders like tumors, inflammation or undesired cell apoptosis. In this study a linear binding motif from the RHDF1 protein—a 15 amino acids long peptide—was selected for optimization to increase its cellular uptake but retaining its low micromolar binding affinity. First, we synthesized an octaarginine conjugate that showed efficient cellular uptake. Next, we set out to reduce the size of this construct. We were able to decrease the length of the original peptide, and to increase its cellular uptake with specific chemical modifications. These new constructs bound better to ERK2 and p38 kinases than the original peptide and they showed markedly increased cellular uptake. The new octaarginine conjugate and one of the minimized bicyclic derivatives could inhibit the phosphorylation of intracellular ERK or p38. However, the modulation of MAPK phosphorylation levels by these cell-penetrating peptides were complex, despite that in biochemical assays they all inhibited MAPK-substrate binding as well as phosphorylation. The optimized peptides depending on the applied concentration caused an expected decrease, but also some unexpected increase in MAPK phosphorylation patterns in the cell. This possibly reflects the complexity of MAPK docking groove mediated protein–protein interactions including bone fide MAPK clients such activator kinases, deactivating phosphatases or regulatory scaffolds. Thus, our findings with optimized cell-penetrating “inhibitory” peptides highlight the opportunities but also the pitfalls of docking peptide based MAPK activity regulation and call for a better quantitative understanding of MAPK mediated protein–protein interactions in cells.
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Affiliation(s)
- Anita Alexa
- Biomolecular Interactions Laboratory, Institute of Organic Chemistry, Research Centre for Natural Sciences, Budapest, Hungary
| | - Orsolya Ember
- Biomolecular Interactions Laboratory, Institute of Organic Chemistry, Research Centre for Natural Sciences, Budapest, Hungary.,Department of Organic Chemistry, Institute of Chemistry, Eötvös Loránd University, Budapest, Hungary
| | - Ildikó Szabó
- MTA-ELTE Research Group of Peptide Chemistry, Eötvös Loránd Research Network (ELKH), Eötvös L. University, Budapest, Hungary
| | - Yousef Mo'ath
- Department of Organic Chemistry, Institute of Chemistry, Eötvös Loránd University, Budapest, Hungary
| | - Ádám L Póti
- Biomolecular Interactions Laboratory, Institute of Organic Chemistry, Research Centre for Natural Sciences, Budapest, Hungary
| | - Attila Reményi
- Biomolecular Interactions Laboratory, Institute of Organic Chemistry, Research Centre for Natural Sciences, Budapest, Hungary
| | - Zoltán Bánóczi
- Department of Organic Chemistry, Institute of Chemistry, Eötvös Loránd University, Budapest, Hungary
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6
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Kumar GS, Page R, Peti W. The interaction of p38 with its upstream kinase MKK6. Protein Sci 2021; 30:908-913. [PMID: 33554397 DOI: 10.1002/pro.4039] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 01/29/2021] [Accepted: 02/02/2021] [Indexed: 02/06/2023]
Abstract
Mitogen-activated protein kinase (MAPK; p38, ERK, and JNK) cascades are evolutionarily conserved signaling pathways that regulate the cellular response to a variety of extracellular stimuli, such as growth factors and interleukins. The MAPK p38 is activated by its specific upstream MAPK kinases, MKK6 and MKK3. However, a comprehensive molecular understanding of how these cognate upstream kinases bind and activate p38 is still missing. Here, we combine NMR spectroscopy and isothermal titration calorimetry to define the binding interface between full-length MKK6 and p38. It was shown that p38 engages MKK6 not only via its hydrophobic docking groove, but also influences helix αF, a secondary structural element that plays a key role in organizing the kinase core. It was also shown that, unlike MAPK phosphatases, the p38 conserved docking (CD) site is much less affected by MKK6 binding. Finally, it was demonstrated that these interactions with p38 are conserved independent of the MKK6 activation state. Together, the results revealed differences between specificity markers of p38 regulation by upstream kinases, which do not effectively engage the CD site, and downstream phosphatases, which require the CD site for productive binding.
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Affiliation(s)
- Ganesan Senthil Kumar
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, Connecticut, USA
| | - Rebecca Page
- Department of Cell Biology, University of Connecticut Health Center, Farmington, Connecticut, USA
| | - Wolfgang Peti
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, Connecticut, USA
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7
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Adhikari N, Kuburich NA, Hadwiger JA. Mitogen-activated protein kinase regulation of the phosphodiesterase RegA in early Dictyostelium development. MICROBIOLOGY-SGM 2020; 166:129-140. [PMID: 31730032 DOI: 10.1099/mic.0.000868] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Mitogen-activated protein kinase (MAPK) regulation of cAMP-specific phosphodiesterase function has been demonstrated in mammalian cells and suspected to occur in other eukaryotes. Epistasis analysis in the soil amoeba Dictyostelium discoideum suggests the atypical MAPK Erk2 downregulates the function of the cAMP-specific phosphodiesterase RegA to regulate progression of the developmental life cycle. A putative MAPK docking motif located near a predicted MAPK phosphorylation site was characterized for contributions to RegA function and binding to Erk2 because a similar docking motif has been previously characterized in the mammalian PDE4D phosphodiesterase. The overexpression of RegA with alterations to this docking motif (RegAD-) restored RegA function to regA- cells based on developmental phenotypes, but low-level expression of RegAD- from the endogenous regA promoter failed to rescue wild-type morphogenesis. Co-immunoprecipitation analysis indicated that Erk2 associates with both RegA and RegAD-, suggesting the docking motif is not required for this association. Epistasis analysis between regA and the only other Dictyostelium MAPK, erk1, suggests Erk1 and RegA can function in different pathways but that some erk1- phenotypes may require cAMP signalling. These results imply that MAPK downregulation of RegA in Dictyostelium is accomplished through a different mechanism than MAPK regulation of cAMP-specific phosphodiesterases in mammalian cells and that the regulation in Dictyostelium does not require a proximal MAPK docking motif.
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Affiliation(s)
- Nirakar Adhikari
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74078-3020, USA
| | - Nick A Kuburich
- Present address: Department of Translational Molecular Pathology, University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA.,Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74078-3020, USA
| | - Jeffrey A Hadwiger
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74078-3020, USA
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Ancient MAPK ERK7 is regulated by an unusual inhibitory scaffold required for Toxoplasma apical complex biogenesis. Proc Natl Acad Sci U S A 2020; 117:12164-12173. [PMID: 32409604 PMCID: PMC7275706 DOI: 10.1073/pnas.1921245117] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Apicomplexan parasites include organisms that cause widespread and devastating human diseases such as malaria, cryptosporidiosis, and toxoplasmosis. These parasites are named for a structure, called the “apical complex,” that organizes their invasion and secretory machinery. We found that two proteins, apical cap protein 9 (AC9) and an enzyme called ERK7, work together to facilitate apical complex assembly. Intriguingly, ERK7 is an ancient molecule that is found throughout Eukaryota, though its regulation and function are poorly understood. AC9 is a scaffold that concentrates ERK7 at the base of the developing apical complex. In addition, AC9 binding likely confers substrate selectivity upon ERK7. This simple competitive regulatory model may be a powerful but largely overlooked mechanism throughout biology. Apicomplexan parasites use a specialized cilium structure called the apical complex to organize their secretory organelles and invasion machinery. The apical complex is integrally associated with both the parasite plasma membrane and an intermediate filament cytoskeleton called the inner-membrane complex (IMC). While the apical complex is essential to the parasitic lifestyle, little is known about the regulation of apical complex biogenesis. Here, we identify AC9 (apical cap protein 9), a largely intrinsically disordered component of the Toxoplasma gondii IMC, as essential for apical complex development, and therefore for host cell invasion and egress. Parasites lacking AC9 fail to successfully assemble the tubulin-rich core of their apical complex, called the conoid. We use proximity biotinylation to identify the AC9 interaction network, which includes the kinase extracellular signal-regulated kinase 7 (ERK7). Like AC9, ERK7 is required for apical complex biogenesis. We demonstrate that AC9 directly binds ERK7 through a conserved C-terminal motif and that this interaction is essential for ERK7 localization and function at the apical cap. The crystal structure of the ERK7–AC9 complex reveals that AC9 is not only a scaffold but also inhibits ERK7 through an unusual set of contacts that displaces nucleotide from the kinase active site. ERK7 is an ancient and autoactivating member of the mitogen-activated kinase (MAPK) family and its regulation is poorly understood in all organisms. We propose that AC9 dually regulates ERK7 by scaffolding and concentrating it at its site of action while maintaining it in an “off” state until the specific binding of a true substrate.
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9
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Zhan Y, Liang J, Tian K, Che Z, Wang Z, Yang X, Su Y, Lin X, Song F, Zhao J, Xu J, Liu Q, Zhou B. Vindoline Inhibits RANKL-Induced Osteoclastogenesis and Prevents Ovariectomy-Induced Bone Loss in Mice. Front Pharmacol 2020; 10:1587. [PMID: 32038256 PMCID: PMC6987431 DOI: 10.3389/fphar.2019.01587] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 12/09/2019] [Indexed: 12/31/2022] Open
Abstract
Osteolytic bone diseases, for example postmenopausal osteoporosis, arise from the imbalances between osteoclasts and osteoblasts in the bone remodeling process, whereby osteoclastic bone resorption greatly exceeds osteoblastic bone formation resulting in severe bone loss and deterioration in bone structure and microarchitecture. Therefore, the identification of agents that can inhibit osteoclast formation and/or function for the treatment of osteolytic bone disease has been the focus of bone and orthopedic research. Vindoline (Vin), an indole alkaloid extracted from the medicinal plant Catharanthus roseus, has been shown to possess extensive biological and pharmacological benefits, but its effects on bone metabolism remains to be documented. Our study demonstrated for the first time, that Vin could inhibit osteoclast differentiation from bone marrow macrophages (BMMs) precursor cells as well as mature osteoclastic bone resorption. We further determined that the underlying molecular mechanism of action of Vin is in part due to its inhibitory effect against the activation of MAPK including p38, JNK, and ERK and intracellular reactive oxygen species (ROS) production. This effect ultimately suppressed the induction of c-Fos and NFATc1, which consequently downregulated the expression of the genes required for osteoclast formation and bone resorption. Consistent with our in vitro findings, in vivo administration of Vin protected mice against ovariectomy (OVX)-induced bone loss and trabecular bone deterioration. These results provided promising evidence for the potential therapeutic application of Vin as a novel treatment option against osteolytic diseases.
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Affiliation(s)
- Yunfei Zhan
- Guangxi Key Laboratory of Regenerative Medicine, Guangxi Medical University, Nanning, China
| | - Jiamin Liang
- Guangxi Key Laboratory of Regenerative Medicine, Guangxi Medical University, Nanning, China
| | - Kun Tian
- Guangxi Key Laboratory of Regenerative Medicine, Guangxi Medical University, Nanning, China
| | - Zhigang Che
- Guangxi Key Laboratory of Regenerative Medicine, Guangxi Medical University, Nanning, China
| | - Ziyi Wang
- School of Biomedical Sciences, The University of Western Australia, Perth, WA, Australia
| | - Xue Yang
- Guangxi Key Laboratory of Regenerative Medicine, Guangxi Medical University, Nanning, China
| | - Yuangang Su
- Guangxi Key Laboratory of Regenerative Medicine, Guangxi Medical University, Nanning, China
| | - Xixi Lin
- Guangxi Key Laboratory of Regenerative Medicine, Guangxi Medical University, Nanning, China
| | - Fangming Song
- Guangxi Key Laboratory of Regenerative Medicine, Guangxi Medical University, Nanning, China.,School of Biomedical Sciences, The University of Western Australia, Perth, WA, Australia
| | - Jinmin Zhao
- Guangxi Key Laboratory of Regenerative Medicine, Guangxi Medical University, Nanning, China.,Department of Trauma Orthopedic and Hand Surgery, Research Centre for Regenerative Medicine, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Jiake Xu
- Guangxi Key Laboratory of Regenerative Medicine, Guangxi Medical University, Nanning, China.,School of Biomedical Sciences, The University of Western Australia, Perth, WA, Australia
| | - Qian Liu
- Guangxi Key Laboratory of Regenerative Medicine, Guangxi Medical University, Nanning, China.,Department of Trauma Orthopedic and Hand Surgery, Research Centre for Regenerative Medicine, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Bo Zhou
- Guangxi Key Laboratory of Regenerative Medicine, Guangxi Medical University, Nanning, China
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10
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Petrides A, Vinnicombe G. Enzyme sequestration by the substrate: An analysis in the deterministic and stochastic domains. PLoS Comput Biol 2018; 14:e1006107. [PMID: 29771922 PMCID: PMC5976211 DOI: 10.1371/journal.pcbi.1006107] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 05/30/2018] [Accepted: 03/26/2018] [Indexed: 11/19/2022] Open
Abstract
This paper is concerned with the potential multistability of protein concentrations in the cell. That is, situations where one, or a family of, proteins may sit at one of two or more different steady state concentrations in otherwise identical cells, and in spite of them being in the same environment. For models of multisite protein phosphorylation for example, in the presence of excess substrate, it has been shown that the achievable number of stable steady states can increase linearly with the number of phosphosites available. In this paper, we analyse the consequences of adding enzyme docking to these and similar models, with the resultant sequestration of phosphatase and kinase by the fully unphosphorylated and by the fully phosphorylated substrates respectively. In the large molecule numbers limit, where deterministic analysis is applicable, we prove that there are always values for these rates of sequestration which, when exceeded, limit the extent of multistability. For the models considered here, these numbers are much smaller than the affinity of the enzymes to the substrate when it is in a modifiable state. As substrate enzyme-sequestration is increased, we further prove that the number of steady states will inevitably be reduced to one. For smaller molecule numbers a stochastic analysis is more appropriate, where multistability in the large molecule numbers limit can manifest itself as multimodality of the probability distribution; the system spending periods of time in the vicinity of one mode before jumping to another. Here, we find that substrate enzyme sequestration can induce bimodality even in systems where only a single steady state can exist at large numbers. To facilitate this analysis, we develop a weakly chained diagonally dominant M-matrix formulation of the Chemical Master Equation, allowing greater insights in the way particular mechanisms, like enzyme sequestration, can shape probability distributions and therefore exhibit different behaviour across different regimes.
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Affiliation(s)
- Andreas Petrides
- Department of Engineering, University of Cambridge, Cambridge, United Kingdom
| | - Glenn Vinnicombe
- Department of Engineering, University of Cambridge, Cambridge, United Kingdom
- * E-mail:
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11
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Yu ZH, Zhang ZY. Regulatory Mechanisms and Novel Therapeutic Targeting Strategies for Protein Tyrosine Phosphatases. Chem Rev 2018; 118:1069-1091. [PMID: 28541680 PMCID: PMC5812791 DOI: 10.1021/acs.chemrev.7b00105] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
An appropriate level of protein phosphorylation on tyrosine is essential for cells to react to extracellular stimuli and maintain cellular homeostasis. Faulty operation of signal pathways mediated by protein tyrosine phosphorylation causes numerous human diseases, which presents enormous opportunities for therapeutic intervention. While the importance of protein tyrosine kinases in orchestrating the tyrosine phosphorylation networks and in target-based drug discovery has long been recognized, the significance of protein tyrosine phosphatases (PTPs) in cellular signaling and disease biology has historically been underappreciated, due to a large extent to an erroneous assumption that they are largely constitutive and housekeeping enzymes. Here, we provide a comprehensive examination of a number of regulatory mechanisms, including redox modulation, allosteric regulation, and protein oligomerization, that control PTP activity. These regulatory mechanisms are integral to the myriad PTP-mediated biochemical events and reinforce the concept that PTPs are indispensable and specific modulators of cellular signaling. We also discuss how disruption of these PTP regulatory mechanisms can cause human diseases and how these diverse regulatory mechanisms can be exploited for novel therapeutic development.
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Affiliation(s)
- Zhi-Hong Yu
- Department of Medicinal Chemistry and Molecular Pharmacology, Department of Chemistry, Center for Cancer Research, and Institute for Drug Discovery, Purdue University, 720 Clinic Drive, West Lafayette, IN 47907
| | - Zhong-Yin Zhang
- Department of Medicinal Chemistry and Molecular Pharmacology, Department of Chemistry, Center for Cancer Research, and Institute for Drug Discovery, Purdue University, 720 Clinic Drive, West Lafayette, IN 47907
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12
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Jang Y, Kim MA, Kim Y. Two faces of competition: target-mediated reverse signalling in microRNA and mitogen-activated protein kinase regulatory networks. IET Syst Biol 2017; 11:105-113. [PMID: 28721939 PMCID: PMC8687413 DOI: 10.1049/iet-syb.2016.0042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2016] [Revised: 03/14/2017] [Accepted: 03/29/2017] [Indexed: 11/19/2022] Open
Abstract
Biomolecular regulatory networks are organised around hubs, which can interact with a large number of targets. These targets compete with each other for access to their common hubs, but whether the effect of this competition would be significant in magnitude and in function is not clear. In this review, the authors discuss recent in vivo studies that analysed the system level retroactive effects induced by target competition in microRNA and mitogen-activated protein kinase regulatory networks. The results of these studies suggest that downstream targets can regulate the overall state of their upstream regulators, and thus cannot be ignored in analysing biomolecular networks.
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Affiliation(s)
- Yongjin Jang
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea
| | - Min A Kim
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea
| | - Yoosik Kim
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea.
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13
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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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Bardwell AJ, Bardwell L. Two hydrophobic residues can determine the specificity of mitogen-activated protein kinase docking interactions. J Biol Chem 2015; 290:26661-74. [PMID: 26370088 DOI: 10.1074/jbc.m115.691436] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Indexed: 11/06/2022] Open
Abstract
MAPKs bind to many of their upstream regulators and downstream substrates via a short docking motif (the D-site) on their binding partner. MAPKs that are in different families (e.g. ERK, JNK, and p38) can bind selectively to D-sites in their authentic substrates and regulators while discriminating against D-sites in other pathways. Here we demonstrate that the short hydrophobic region at the distal end of the D-site plays a critical role in determining the high selectivity of JNK MAPKs for docking sites in their cognate MAPK kinases. Changing just 1 or 2 key hydrophobic residues in this submotif is sufficient to turn a weak JNK-binding D-site into a strong one, or vice versa. These specificity-determining differences are also found in the D-sites of the ETS family transcription factors Elk-1 and Net. Moreover, swapping two hydrophobic residues between these D-sites switches the relative efficiency of Elk-1 and Net as substrates for ERK versus JNK, as predicted. These results provide new insights into docking specificity and suggest that this specificity can evolve rapidly by changes to just 1 or 2 amino acids.
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Affiliation(s)
- A Jane Bardwell
- From the Department of Developmental and Cell Biology, Center for Complex Biological Systems, University of California, Irvine, California 92697
| | - Lee Bardwell
- From the Department of Developmental and Cell Biology, Center for Complex Biological Systems, University of California, Irvine, California 92697
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Mapping the binding interface of ERK and transcriptional repressor Capicua using photocrosslinking. Proc Natl Acad Sci U S A 2015; 112:8590-5. [PMID: 26124095 DOI: 10.1073/pnas.1501373112] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Extracellular signal-regulated kinase (ERK) coordinates cellular responses to a range of stimuli by phosphorylating its numerous substrates. One of these substrates, Capicua (Cic), is a transcriptional repressor that was first identified in Drosophila and has been implicated in a number of human diseases. Here we use a chemical biology approach to map the binding interface of ERK and Cic. The noncanonical amino acid p-azidophenylalanine (AzF) was introduced into the ERK-binding region of Drosophila Cic, and photocrosslinking and tandem mass spectrometry were used to pinpoint its binding site on ERK. We also identified the ERK-binding region of human Cic and showed that it binds to the same site on ERK despite lacking conservation with the Drosophila Cic binding region. Finally, we mapped the amino acids involved in human Cic binding to ERK using AzF-labeled ERK. These results reveal the molecular details of the ERK-Cic interaction and demonstrate that the photocrosslinking approach is complementary to existing methods for mapping kinase-substrate binding interfaces.
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Luo ML, Gong C, Chen CH, Hu H, Huang P, Zheng M, Yao Y, Wei S, Wulf G, Lieberman J, Zhou XZ, Song E, Lu KP. The Rab2A GTPase promotes breast cancer stem cells and tumorigenesis via Erk signaling activation. Cell Rep 2015; 11:111-24. [PMID: 25818297 PMCID: PMC4401741 DOI: 10.1016/j.celrep.2015.03.002] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 01/14/2015] [Accepted: 02/26/2015] [Indexed: 12/31/2022] Open
Abstract
Proline-directed phosphorylation is regulated by the prolyl isomerase Pin1, which plays a fundamental role in driving breast cancer stem-like cells (BCSCs). Rab2A is a small GTPase critical for vesicle trafficking. Here, we show that Pin1 increases Rab2A transcription to promote BCSC expansion and tumorigenesis in vitro and in vivo. Mechanistically, Rab2A directly interacts with and prevents dephosphorylation/inactivation of Erk1/2 by the MKP3 phosphatase, resulting in Zeb1 upregulation and β-catenin nuclear translocation. In cancer cells, Rab2A is activated via gene amplification, mutation or Pin1 overexpression. Rab2A overexpression or mutation endows BCSC traits to primary normal human breast epithelial cells, whereas silencing Rab2A potently inhibits the expansion and tumorigenesis of freshly isolated BCSCs. Finally, Rab2A overexpression correlates with poor clinical outcome in breast cancer patients. Thus, Pin1/Rab2A/Erk drives BCSC expansion and tumorigenicity, suggesting potential drug targets.
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Affiliation(s)
- Man-Li Luo
- Department of Medicine and Cancer Research Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; Breast Tumor Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Chang Gong
- Breast Tumor Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Chun-Hau Chen
- Department of Medicine and Cancer Research Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Hai Hu
- Department of Medicine and Cancer Research Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Pengyu Huang
- Department of Medicine and Cancer Research Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Min Zheng
- Department of Medicine and Cancer Research Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; Institute for Translational Medicine, Fujian Medical University, Fuzhou 350108, China
| | - Yandan Yao
- Department of Medicine and Cancer Research Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; Breast Tumor Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Shuo Wei
- Department of Medicine and Cancer Research Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Gerburg Wulf
- Department of Medicine and Cancer Research Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Judy Lieberman
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Xiao Zhen Zhou
- Department of Medicine and Cancer Research Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Erwei Song
- Breast Tumor Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Kun Ping Lu
- Department of Medicine and Cancer Research Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; Institute for Translational Medicine, Fujian Medical University, Fuzhou 350108, China.
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17
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Prabakaran S, Gunawardena J, Sontag E. Paradoxical results in perturbation-based signaling network reconstruction. Biophys J 2015; 106:2720-8. [PMID: 24940789 DOI: 10.1016/j.bpj.2014.04.031] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 04/18/2014] [Accepted: 04/23/2014] [Indexed: 11/29/2022] Open
Abstract
Mathematical models are extensively employed to understand physicochemical processes in biological systems. In the absence of detailed mechanistic knowledge, models are often based on network inference methods, which in turn rely upon perturbations to nodes by biochemical means. We have discovered a potential pitfall of the approach underpinning such methods when applied to signaling networks. We first show experimentally, and then explain mathematically, how even in the simplest signaling systems, perturbation methods may lead to paradoxical conclusions: for any given pair of two components X and Y, and depending upon the specific intervention on Y, either an activation or a repression of X could be inferred. This effect is of a different nature from incomplete network identification due to underdetermined data and is a phenomenon intrinsic to perturbations. Our experiments are performed in an in vitro minimal system, thus isolating the effect and showing that it cannot be explained by feedbacks due to unknown intermediates. Moreover, our in vitro system utilizes proteins from a pathway in mammalian (and other eukaryotic) cells that play a central role in proliferation, gene expression, differentiation, mitosis, cell survival, and apoptosis. This pathway is the perturbation target of contemporary therapies for various types of cancers. The results presented here show that the simplistic view of intracellular signaling networks being made up of activation and repression links is seriously misleading, and call for a fundamental rethinking of signaling network analysis and inference methods.
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Affiliation(s)
| | - Jeremy Gunawardena
- Department of Systems Biology, Harvard Medical School, Boston Massachusetts
| | - Eduardo Sontag
- Department of Mathematics & BioMaPs Institute for Quantitative Biology, Rutgers University, Piscataway, New Jersey.
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18
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Zhang X, Wang L, Xu X, Cai C, Guo W. Genome-wide identification of mitogen-activated protein kinase gene family in Gossypium raimondii and the function of their corresponding orthologs in tetraploid cultivated cotton. BMC PLANT BIOLOGY 2014; 14:345. [PMID: 25492847 PMCID: PMC4270029 DOI: 10.1186/s12870-014-0345-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Accepted: 11/20/2014] [Indexed: 05/18/2023]
Abstract
BACKGROUND Mitogen-activated protein kinase (MAPK) cascades play a crucial role in plant growth and development as well as biotic and abiotic stress responses. Knowledge about the MAPK gene family in cotton is limited, and systematic investigation of MAPK family proteins has not been reported. RESULTS By performing a bioinformatics homology search, we identified 28 putative MAPK genes in the Gossypium raimondii genome. These MAPK members were anchored onto 11 chromosomes in G. raimondii, with uneven distribution. Phylogenetic analysis showed that the MAPK candidates could be classified into the four known A, B, C and D groups, with more MAPKs containing the TEY phosphorylation site (18 members) than the TDY motif (10 members). Furthermore, 21 cDNA sequences of MAPKs with complete open reading frames (ORFs) were identified in G. hirsutum via PCR-based approaches, including 13 novel MAPKs and eight with homologs reported previously in tetraploid cotton. The expression patterns of 23 MAPK genes reveal their important roles in diverse functions in cotton, in both various developmental stages of vegetative and reproductive growth and in the stress response. Using a reverse genetics approach based on tobacco rattle virus-induced gene silencing (TRV-VIGS), we further verified that MPK9, MPK13 and MPK25 confer resistance to defoliating isolates of Verticillium dahliae in cotton. Silencing of MPK9, MPK13 and MPK25 can significantly enhance cotton susceptibility to this pathogen. CONCLUSIONS This study presents a comprehensive identification of 28 mitogen-activated protein kinase genes in G. raimondii. Their phylogenetic relationships, transcript expression patterns and responses to various stressors were verified. This study provides the first systematic analysis of MAPKs in cotton, improving our understanding of defense responses in general and laying the foundation for future crop improvement using MAPKs.
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Affiliation(s)
- Xueying Zhang
- State Key Laboratory of Crop Genetics & Germplasm Enhancement, Hybrid Cotton R & D Engineering Research Center, MOE, Nanjing Agricultural University, Nanjing, 210095, Jiangsu Province, P. R. China.
| | - Liman Wang
- State Key Laboratory of Crop Genetics & Germplasm Enhancement, Hybrid Cotton R & D Engineering Research Center, MOE, Nanjing Agricultural University, Nanjing, 210095, Jiangsu Province, P. R. China.
| | - Xiaoyang Xu
- State Key Laboratory of Crop Genetics & Germplasm Enhancement, Hybrid Cotton R & D Engineering Research Center, MOE, Nanjing Agricultural University, Nanjing, 210095, Jiangsu Province, P. R. China.
| | - Caiping Cai
- State Key Laboratory of Crop Genetics & Germplasm Enhancement, Hybrid Cotton R & D Engineering Research Center, MOE, Nanjing Agricultural University, Nanjing, 210095, Jiangsu Province, P. R. China.
| | - Wangzhen Guo
- State Key Laboratory of Crop Genetics & Germplasm Enhancement, Hybrid Cotton R & D Engineering Research Center, MOE, Nanjing Agricultural University, Nanjing, 210095, Jiangsu Province, P. R. China.
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19
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Cao Y, Du M, Luo S, Xia Y. Calcineurin modulates growth, stress tolerance, and virulence in Metarhizium acridum and its regulatory network. Appl Microbiol Biotechnol 2014; 98:8253-65. [DOI: 10.1007/s00253-014-5876-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2014] [Revised: 05/23/2014] [Accepted: 05/29/2014] [Indexed: 10/25/2022]
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20
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Veide Vilg J, Dahal S, Ljungdahl T, Grøtli M, Tamás MJ. Application of a peptide-based assay to characterize inhibitors targeting protein kinases from yeast. Curr Genet 2014; 60:193-200. [DOI: 10.1007/s00294-014-0424-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 02/27/2014] [Indexed: 11/29/2022]
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21
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Ahmed S, Grant KG, Edwards LE, Rahman A, Cirit M, Goshe MB, Haugh JM. Data-driven modeling reconciles kinetics of ERK phosphorylation, localization, and activity states. Mol Syst Biol 2014; 10:718. [PMID: 24489118 PMCID: PMC4023404 DOI: 10.1002/msb.134708] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The extracellular signal‐regulated kinase (ERK) signaling pathway controls cell proliferation and differentiation in metazoans. Two hallmarks of its dynamics are adaptation of ERK phosphorylation, which has been linked to negative feedback, and nucleocytoplasmic shuttling, which allows active ERK to phosphorylate protein substrates in the nucleus and cytosol. To integrate these complex features, we acquired quantitative biochemical and live‐cell microscopy data to reconcile phosphorylation, localization, and activity states of ERK. While maximal growth factor stimulation elicits transient ERK phosphorylation and nuclear translocation responses, ERK activities available to phosphorylate substrates in the cytosol and nuclei show relatively little or no adaptation. Free ERK activity in the nucleus temporally lags the peak in nuclear translocation, indicating a slow process. Additional experiments, guided by kinetic modeling, show that this process is consistent with ERK's modification of and release from nuclear substrate anchors. Thus, adaptation of whole‐cell ERK phosphorylation is a by‐product of transient protection from phosphatases. Consistent with this interpretation, predictions concerning the dose‐dependence of the pathway response and its interruption by inhibition of MEK were experimentally confirmed.
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Affiliation(s)
- Shoeb Ahmed
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
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22
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Combining docking site and phosphosite predictions to find new substrates: identification of smoothelin-like-2 (SMTNL2) as a c-Jun N-terminal kinase (JNK) substrate. Cell Signal 2013; 25:2518-29. [PMID: 23981301 DOI: 10.1016/j.cellsig.2013.08.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 08/05/2013] [Accepted: 08/06/2013] [Indexed: 12/20/2022]
Abstract
Specific docking interactions between mitogen-activated protein kinases (MAPKs), their regulators, and their downstream substrates, are crucial for efficient and accurate signal transmission. To identify novel substrates of the c-Jun N-terminal kinase (JNK) family of MAPKs, we searched the human genome for proteins that contained (1), a predicted JNK-docking site (D-site); and (2), a cluster of putative JNK target phosphosites located close to the D-site. Here we describe a novel JNK substrate that emerged from this analysis, the functionally uncharacterized protein smoothelin-like 2 (SMTNL2). SMTNL2 protein bound with high-affinity to multiple MAPKs including JNK1-3 and ERK2; furthermore, the identity of conserved amino acids in the predicted docking site (residues 180-193) was necessary for this high-affinity binding. In addition, purified full-length SMTNL2 protein was phosphorylated by JNK1-3 in vitro, and this required the integrity of the D-site. Using mass spectrometry and mutagenesis, we identified four D-site-dependent phosphoacceptor sites in close proximity to the docking site, at S217, S241, T236 and T239. A short peptide comprised of the SMTNL2 D-site inhibited JNK-mediated phosphorylation of the ATF2 transcription factor, showing that SMTNL2 can compete with other substrates for JNK binding. Moreover, when transfected into HEK293 cells, SMTNL2 was phosphorylated by endogenous JNK in a D-site dependent manner, on the same residues identified in vitro. SMTNL2 protein was expressed in many mammalian tissues, with a notably high expression in skeletal muscle. Consistent with the hypothesis that SMTNL2 has a function in skeletal muscle, SMTNL2 protein expression was strongly induced during the transition from myoblasts to myotubes in differentiating C2C12 cells.
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Mann JK, Wood JF, Stephan AF, Tzanakakis ES, Ferkey DM, Park S. Epitope-guided engineering of monobody binders for in vivo inhibition of Erk-2 signaling. ACS Chem Biol 2013; 8:608-16. [PMID: 23227961 PMCID: PMC3600092 DOI: 10.1021/cb300579e] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Although the affinity optimization of protein binders is straightforward, engineering epitope specificity is more challenging. Targeting a specific surface patch is important because the biological relevance of protein binders depends on how they interact with the target. They are particularly useful to test hypotheses motivated by biochemical and structural studies. We used yeast display to engineer monobodies that bind a defined surface patch on the mitogen activated protein kinase (MAPK) Erk-2. The targeted area ("CD" domain) is known to control the specificity and catalytic efficiency of phosphorylation by the kinase by binding a linear peptide ("D" peptide) on substrates and regulators. An inhibitor of the interaction should thus be useful for regulating Erk-2 signaling in vivo. Although the CD domain constitutes only a small percentage of the surface area of the enzyme (~5%), sorting a yeast displayed monobody library with wild type (wt) Erk-2 and a rationally designed mutant led to isolation of high affinity clones with desired epitope specificity. The engineered binders inhibited the activity of Erk-2 in vitro and in mammalian cells. Furthermore, they specifically inhibited the activity of Erk-2 orthologs in yeast and suppressed a mutant phenotype in round worms caused by overactive MAPK signaling. The study therefore shows that positive and negative screening can be used to bias the evolution of epitope specificity and predictably design inhibitors of biologically relevant protein-protein interaction.
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Affiliation(s)
- Jasdeep K. Mann
- Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, NY 14260
| | - Jordan F. Wood
- Department of Biological Sciences, University at Buffalo, State University of New York, NY 14260
| | - Anne Fleur Stephan
- Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, NY 14260
| | - Emmanuel S. Tzanakakis
- Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, NY 14260
- Department of Biomedical Engineering, University at Buffalo, State University of New York, NY 14260
- Western New York Stem Cell Culture and Analysis Center, University at Buffalo, State University of New York, NY 14260
| | - Denise M. Ferkey
- Department of Biological Sciences, University at Buffalo, State University of New York, NY 14260
| | - Sheldon Park
- Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, NY 14260
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From FRET Imaging to Practical Methodology for Kinase Activity Sensing in Living Cells. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 113:145-216. [DOI: 10.1016/b978-0-12-386932-6.00005-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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25
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Garai Á, Zeke A, Gógl G, Törő I, Fördős F, Blankenburg H, Bárkai T, Varga J, Alexa A, Emig D, Albrecht M, Reményi A. Specificity of linear motifs that bind to a common mitogen-activated protein kinase docking groove. Sci Signal 2012; 5:ra74. [PMID: 23047924 DOI: 10.1126/scisignal.2003004] [Citation(s) in RCA: 122] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Mitogen-activated protein kinases (MAPKs) have a docking groove that interacts with linear "docking" motifs in binding partners. To determine the structural basis of binding specificity between MAPKs and docking motifs, we quantitatively analyzed the ability of 15 docking motifs from diverse MAPK partners to bind to c-Jun amino-terminal kinase 1 (JNK1), p38α, and extracellular signal-regulated kinase 2 (ERK2). Classical docking motifs mediated highly specific binding only to JNK1, and only those motifs with a sequence pattern distinct from the classical MAPK binding docking motif consensus differentiated between the topographically similar docking grooves of ERK and p38α. Crystal structures of four complexes of MAPKs with docking peptides, representing JNK-specific, ERK-specific, or ERK- and p38-selective binding modes, revealed that the regions located between consensus positions in the docking motifs showed conformational diversity. Although the consensus positions in the docking motifs served as anchor points that bound to common MAPK surface features and mostly contributed to docking in a nondiscriminatory fashion, the conformation of the intervening region between the anchor points mostly determined specificity. We designed peptides with tailored MAPK binding profiles by rationally changing the length and amino acid composition of intervening regions located between anchor points. These results suggest a coherent structural model for MAPK docking specificity that reveals how short linear motifs binding to a common kinase docking groove can mediate diverse interaction patterns and contribute to correct MAPK partner selection in signaling networks.
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Affiliation(s)
- Ágnes Garai
- Department of Biochemistry, Eötvös Loránd University, Pázmány Péter sétány 1/C, 1117 Budapest, Hungary
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26
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Napolitano C, Palwai VR, Eriksson LA, Murphy PV. Synthesis, kinase activity and molecular modeling of a resorcylic acid lactone incorporating an amide and a trans-enone in the macrocycle. Tetrahedron 2012. [DOI: 10.1016/j.tet.2012.04.082] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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27
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Hirashima T. A kinetic model of ERK cyclic pathway on substrate control. Math Biosci 2012; 239:207-12. [PMID: 22705338 DOI: 10.1016/j.mbs.2012.05.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Revised: 05/20/2012] [Accepted: 05/22/2012] [Indexed: 12/23/2022]
Abstract
Extracellular signal-regulated kinase (ERK) is a key factor in the widely used signaling cascade of phosphorylation-dephosphorylation cycles and plays pivotal roles in many aspects of biological processes. Experimental studies in yeast and in Drosophila embryo have suggested that the phosphorylation and spatial localization of ERK are influenced by the level of its downstream substrates. However, the mechanism, through which these substrates control properties of ERK signaling, has been unclear. I propose a mass-action kinetic model of ERK cycle with its substrate, and demonstrate that the substrate can modulate the ERK activity by directly interacting with ERK. The model shows that the addition of substrate controls the level of ERK phosphorylation positively or negatively, depending on the balance between dissociation constants of ERK-substrate interaction and properties of ERK cyclic signaling in the absence of the substrate. In addition, by considering cellular compartments, cytosol and nucleus, the substrate can lead to nuclear accumulation of ERK, suggesting that the substrate can act as a nuclear anchor of ERK. The model gives a possible mechanism that can account for substrate-mediated modulation of ERK signaling.
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Affiliation(s)
- Tsuyoshi Hirashima
- Department of Anatomy and Developmental Biology, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan.
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28
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Liu P, Kevrekidis IG, Shvartsman SY. Substrate-dependent control of ERK phosphorylation can lead to oscillations. Biophys J 2012; 101:2572-81. [PMID: 22261044 DOI: 10.1016/j.bpj.2011.10.025] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Revised: 09/13/2011] [Accepted: 10/07/2011] [Indexed: 01/01/2023] Open
Abstract
The extracellular signal-regulated kinase (ERK) controls cellular processes by phosphorylating multiple substrates. The ERK protein can use the same domains to interact with phosphatases, which dephosphorylate and deactivate ERK, and with substrates, which connect ERK to its downstream effects. As a consequence, substrates can compete with phosphatases and control the level of ERK phosphorylation. We propose that this effect can qualitatively change the dynamics of a network that controls ERK activation. On its own, this network can be bistable, but in a larger system, where ERK accelerates the degradation of a substrate competing with a phosphatase, this network can oscillate. Previous studies proposed that oscillatory ERK signaling requires a negative feedback in which active ERK reduces the rate at which it is phosphorylated by upstream kinase. We argue that oscillations can also emerge even when this rate is constant, due to substrate-dependent control of ERK phosphorylation.
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Affiliation(s)
- Ping Liu
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey, USA
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29
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Matsumoto T, Kinoshita T, Matsuzaka H, Nakai R, Kirii Y, Yokota K, Tada T. Crystal structure of non-phosphorylated MAP2K6 in a putative auto-inhibition state. J Biochem 2012; 151:541-9. [DOI: 10.1093/jb/mvs023] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
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30
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Li M, Liu J, Zhang C. Evolutionary history of the vertebrate mitogen activated protein kinases family. PLoS One 2011; 6:e26999. [PMID: 22046431 PMCID: PMC3202601 DOI: 10.1371/journal.pone.0026999] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2011] [Accepted: 10/07/2011] [Indexed: 11/18/2022] Open
Abstract
Background The mitogen activated protein kinases (MAPK) family pathway is implicated in diverse cellular processes and pathways essential to most organisms. Its evolution is conserved throughout the eukaryotic kingdoms. However, the detailed evolutionary history of the vertebrate MAPK family is largely unclear. Methodology/Principal Findings The MAPK family members were collected from literatures or by searching the genomes of several vertebrates and invertebrates with the known MAPK sequences as queries. We found that vertebrates had significantly more MAPK family members than invertebrates, and the vertebrate MAPK family originated from 3 progenitors, suggesting that a burst of gene duplication events had occurred after the divergence of vertebrates from invertebrates. Conservation of evolutionary synteny was observed in the vertebrate MAPK subfamilies 4, 6, 7, and 11 to 14. Based on synteny and phylogenetic relationships, MAPK12 appeared to have arisen from a tandem duplication of MAPK11 and the MAPK13-MAPK14 gene unit was from a segmental duplication of the MAPK11-MAPK12 gene unit. Adaptive evolution analyses reveal that purifying selection drove the evolution of MAPK family, implying strong functional constraints of MAPK genes. Intriguingly, however, intron losses were specifically observed in the MAPK4 and MAPK7 genes, but not in their flanking genes, during the evolution from teleosts to amphibians and mammals. The specific occurrence of intron losses in the MAPK4 and MAPK7 subfamilies might be associated with adaptive evolution of the vertebrates by enhancing the gene expression level of both MAPK genes. Conclusions/Significance These results provide valuable insight into the evolutionary history of the vertebrate MAPK family.
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Affiliation(s)
- Meng Li
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, China
| | - Jun Liu
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, China
| | - Chiyu Zhang
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, China
- * E-mail:
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Recruitment interactions can override catalytic interactions in determining the functional identity of a protein kinase. Proc Natl Acad Sci U S A 2011; 108:9809-14. [PMID: 21628578 DOI: 10.1073/pnas.1016337108] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The yeast Saccharomyces cerevisae has four distinct mitogen-activated protein kinase kinases (MAPKKs), each of which has a distinct functional identity characterized by communication with specific upstream and downstream partners to form distinct functional pathways. These four kinases belong to one family, sharing closely related catalytic domains. How have these four related kinases diverged to take on four distinct functional roles? The specificity of an enzyme for a particular substrate is often thought to reside in differences in the catalytic domain. However, many kinases, including MAPKKs, have modular interaction domains and motifs that have been shown to play an important role in determining the specificity of kinases through recruitment to specific partners and complexes. Here we probe the relative importance of catalytic domain interactions versus recruitment interactions in defining the functional identity of MAPKKs by asking whether we can use recruitment interactions to force other MAPKK catalytic domains to play the functional role of the mating MAPKK, Ste7. We find that two alternative MAPKKs, Pbs2 and Mkk2, can be forced to functionally replace the mating MAPKK Ste7, but only if the proper set of recruitment interactions are grafted onto their catalytic domains. These results show that within a family of kinases, recruitment interactions can play a dominant role in defining functional identity, and is consistent with a model in which new kinase functions can arise through recombination of existing catalytic domains with new interaction modules.
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Substrate-dependent control of MAPK phosphorylation in vivo. Mol Syst Biol 2011; 7:467. [PMID: 21283143 PMCID: PMC3063690 DOI: 10.1038/msb.2010.121] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Accepted: 12/17/2010] [Indexed: 11/09/2022] Open
Abstract
Shvartsman and colleagues demonstrate that downstream nuclear substrates can regulate Drosophila MAPK phosphorylation levels by counteracting cytoplasmic phosphatases, providing in vivo evidence for significant retroactivity in a cellular signaling system. Phosphorylation of the mitogen-activated protein kinase (MAPK) is essential for its enzymatic activity and ability to control multiple substrates inside a cell. According to the current models, control of MAPK phosphorylation is independent of its substrates, which are viewed as mere sensors of MAPK activity. Contrary to this modular view of MAPK signaling, our studies in the Drosophila embryo demonstrate that substrates can regulate the level of MAPK phosphorylation in vivo. We demonstrate that a twofold change in the gene dosage of a single substrate can induce a significant change in the phosphorylation level of MAPK and in the conversion of other substrates. Our results support a model where substrates of MAPK counteract its dephosphorylation by phosphatases. Substrate-dependent control of MAPK phosphorylation is a manifestation of a more general retroactive effect that should be intrinsic to all networks with covalent modification cycles.
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Hadwiger JA, Nguyen HN. MAPKs in development: insights from Dictyostelium signaling pathways. Biomol Concepts 2011; 2:39-46. [PMID: 21666837 DOI: 10.1515/bmc.2011.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Mitogen activated protein kinases (MAPKs) play important roles in the development of eukaryotic organisms through the regulation of signal transduction pathways stimulated by external signals. MAPK signaling pathways have been associated with the regulation of cell growth, differentiation, and chemotaxis, indicating MAPKs contribute to a diverse set of developmental processes. In most eukaryotes, the diversity of external signals is likely to far exceed the diversity of MAPKs, suggesting that multiple signaling pathways might share MAPKs. Do different signaling pathways converge before MAPK function or can MAPKs maintain signaling specificity through interactions with specific proteins? The genetic and biochemical analysis of MAPK pathways in simple eukaryotes such as Dictyostelium offers opportunities to investigate functional specificity of MAPKs in G protein-mediated signal transduction pathways. This review considers the regulation and specificity of MAPK function in pathways that control Dictyostelium growth and development.
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Affiliation(s)
- Jeffrey A Hadwiger
- Department of Microbiology and Molecular Genetics Oklahoma State University 74078-3020, USA
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Napolitano C, Natoni A, Santocanale C, Evensen L, Lorens JB, Murphy PV. Isosteric replacement of the Z-enone with haloethyl ketone and E-enone in a resorcylic acid lactone series and biological evaluation. Bioorg Med Chem Lett 2011; 21:1167-70. [DOI: 10.1016/j.bmcl.2010.12.100] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2010] [Revised: 12/17/2010] [Accepted: 12/21/2010] [Indexed: 10/18/2022]
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Rose BA, Force T, Wang Y. Mitogen-activated protein kinase signaling in the heart: angels versus demons in a heart-breaking tale. Physiol Rev 2010; 90:1507-46. [PMID: 20959622 PMCID: PMC3808831 DOI: 10.1152/physrev.00054.2009] [Citation(s) in RCA: 539] [Impact Index Per Article: 38.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Among the myriad of intracellular signaling networks that govern the cardiac development and pathogenesis, mitogen-activated protein kinases (MAPKs) are prominent players that have been the focus of extensive investigations in the past decades. The four best characterized MAPK subfamilies, ERK1/2, JNK, p38, and ERK5, are the targets of pharmacological and genetic manipulations to uncover their roles in cardiac development, function, and diseases. However, information reported in the literature from these efforts has not yet resulted in a clear view about the roles of specific MAPK pathways in heart. Rather, controversies from contradictive results have led to a perception that MAPKs are ambiguous characters in heart with both protective and detrimental effects. The primary object of this review is to provide a comprehensive overview of the current progress, in an effort to highlight the areas where consensus is established verses the ones where controversy remains. MAPKs in cardiac development, cardiac hypertrophy, ischemia/reperfusion injury, and pathological remodeling are the main focuses of this review as these represent the most critical issues for evaluating MAPKs as viable targets of therapeutic development. The studies presented in this review will help to reveal the major challenges in the field and the limitations of current approaches and point to a critical need in future studies to gain better understanding of the fundamental mechanisms of MAPK function and regulation in the heart.
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Affiliation(s)
- Beth A Rose
- Departments of Anesthesiology, Physiology, and Medicine, David Geffen School of Medicine, Molecular Biology, Institute, University of California at Los Angeles, Los Angeles, CA 90095, USA
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Computational prediction and experimental verification of new MAP kinase docking sites and substrates including Gli transcription factors. PLoS Comput Biol 2010; 6. [PMID: 20865152 PMCID: PMC2928751 DOI: 10.1371/journal.pcbi.1000908] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2010] [Accepted: 07/28/2010] [Indexed: 12/14/2022] Open
Abstract
In order to fully understand protein kinase networks, new methods are needed to identify regulators and substrates of kinases, especially for weakly expressed proteins. Here we have developed a hybrid computational search algorithm that combines machine learning and expert knowledge to identify kinase docking sites, and used this algorithm to search the human genome for novel MAP kinase substrates and regulators focused on the JNK family of MAP kinases. Predictions were tested by peptide array followed by rigorous biochemical verification with in vitro binding and kinase assays on wild-type and mutant proteins. Using this procedure, we found new ‘D-site’ class docking sites in previously known JNK substrates (hnRNP-K, PPM1J/PP2Czeta), as well as new JNK-interacting proteins (MLL4, NEIL1). Finally, we identified new D-site-dependent MAPK substrates, including the hedgehog-regulated transcription factors Gli1 and Gli3, suggesting that a direct connection between MAP kinase and hedgehog signaling may occur at the level of these key regulators. These results demonstrate that a genome-wide search for MAP kinase docking sites can be used to find new docking sites and substrates. Protein kinases are enzymes that regulate key cellular processes by covalently attaching a phosphate group to substrate proteins; they are crucial components of signaling pathways involved in cancer, diabetes, and many other diseases. Identifying the substrates of particular protein kinases is challenging, and many existing biochemical methods are biased against weakly expressed proteins like transcription factors. Here we exploited the observation that mitogen-activated protein kinases (MAPKs) briefly attach to many of their substrates before phosphorylating them, docking onto a sequence known as the ‘D-site’. We developed D-finder, a computational tool that uses a combination of expert knowledge and machine learning to search genome databases for D-sites. We then verified several of D-finder's predictions using rigorous and well-established biochemical assays. The most intriguing predicted and verified substrates were the Gli1 and Gli3 transcription factors of the ‘hedgehog’ signaling pathway. Gli transcription factors are involved in embryonic development and stem cell differentiation, and have also been found to be hyperactive in several types of cancer. There is emerging evidence that crosstalk with MAPK pathways is important in Gli-mediated regulation. Our study, however, is the first to show that MAPKs directly phosphorylate Gli transcription factors.
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MAPK substrate competition integrates patterning signals in the Drosophila embryo. Curr Biol 2010; 20:446-51. [PMID: 20171100 DOI: 10.1016/j.cub.2010.01.019] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2009] [Revised: 01/04/2010] [Accepted: 01/05/2010] [Indexed: 01/06/2023]
Abstract
Terminal regions of the Drosophila embryo are patterned by the localized activation of the mitogen-activated protein kinase (MAPK) pathway. This depends on the MAPK-mediated downregulation of Capicua (Cic), a repressor of the terminal gap genes. We establish that downregulation of Cic is antagonized by the anterior patterning morphogen Bicoid (Bcd). We demonstrate that this effect does not depend on transcriptional activity of Bcd and provide evidence suggesting that Bcd, a direct substrate of MAPK, decreases the availability of MAPK for its other substrates, such as Cic. Based on the quantitative analysis of MAPK signaling in multiple mutants, we propose that MAPK substrate competition coordinates the actions of the anterior and terminal patterning systems. In addition, we identify Hunchback as a novel target of MAPK phosphorylation that can account for the previously described genetic interaction between the posterior and terminal systems. Thus, a common enzyme-substrate competition mechanism can integrate the actions of the anterior, posterior, and terminal patterning signals. Substrate competition can be a general signal integration strategy in networks where enzymes, such as MAPK, interact with their multiple regulators and targets.
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Abstract
MAPK cascade components have been the subject of structural analysis, advancing our understanding of how these enzymes are activated and how they interact. A surprising finding has been that unique inactive conformers are adopted by many of these kinases. These inactive conformers are interesting and often require experimental phases to determine their crystal structures because molecular replacement techniques are not successful. Here, we describe the preparation of MAP2K MEK6 and MAP3K TAO2 substituted with selenomethionine (SeMet) for de novo phasing. TAO2 and SeMet TAO2 were expressed in insect cells.
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Affiliation(s)
- Elizabeth J Goldsmith
- Department of Biochemistry, The University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA.
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Dalkas GA, Papakyriakou A, Vlamis-Gardikas A, Spyroulias GA. Insights into the anthrax lethal factor-substrate interaction and selectivity using docking and molecular dynamics simulations. Protein Sci 2009; 18:1774-85. [PMID: 19585464 DOI: 10.1002/pro.169] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The anthrax toxin of the bacterium Bacillus anthracis consists of three distinct proteins, one of which is the anthrax lethal factor (LF). LF is a gluzincin Zn-dependent, highly specific metalloprotease with a molecular mass of approximately 90 kDa that cleaves most isoforms of the family of mitogen-activated protein kinase kinases (MEKs/MKKs) close to their amino termini, resulting in the inhibition of one or more signaling pathways. Previous studies on the crystal structures of uncomplexed LF and LF complexed with the substrate MEK2 or a MKK-based synthetic peptide provided structure-activity correlations and the basis for the rational design of efficient inhibitors. However, in the crystallographic structures, the substrate peptide was not properly oriented in the active site because of the absence of the catalytic zinc atom. In the current study, docking and molecular dynamics calculations were employed to examine the LF-MEK/MKK interaction along the catalytic channel up to a distance of 20 A from the zinc atom. This residue-specific view of the enzyme-substrate interaction provides valuable information about: (i) the substrate selectivity of LF and its inactivation of MEKs/MKKs (an issue highly important not only to anthrax infection but also to the pathogenesis of cancer), and (ii) the discovery of new, previously unexploited, hot-spots of the LF catalytic channel that are important in the enzyme/substrate binding and interaction.
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Affiliation(s)
- Georgios A Dalkas
- Department of Pharmacy, University of Patras, GR-26504, Patras, Greece
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Awale M, Kumar V, Saravanan P, Mohan CG. Homology modeling and atomic level binding study of Leishmania MAPK with inhibitors. J Mol Model 2009; 16:475-88. [PMID: 19649663 DOI: 10.1007/s00894-009-0565-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2009] [Accepted: 07/08/2009] [Indexed: 12/11/2022]
Abstract
The current therapy for leishmaniasis is not sufficient and it has two severe drawbacks, host-toxicity and drug resistance. The substantial knowledge of parasite biology is not yet translating into novel drugs for leishmaniasis. Based on this observation, a 3D structural model of Leishmania mitogen-activated protein kinase (MAPK) homologue has been developed, for the first time, by homology modeling and molecular dynamics simulation techniques. The model provided clear insight in its structure features, i.e. ATP binding pocket, phosphorylation lip, and common docking site. Sequence-structure homology recognition identified Leishmania CRK3 (LCRK3) as a distant member of the MAPK superfamily. Multiple sequence alignment and 3D structure model provided the putative ATP binding pocket of Leishmania with respect to human ERK2 and LCRK3. This analysis was helpful in identifying the binding sites and molecular function of the Leishmania specific MAPK homologue. Molecular docking study was performed on this 3D structural model, using different classes of competitive ATP inhibitors of LCRK3, to check whether they exhibit affinity and could be identified as Leishmania MAPK specific inhibitors. It is well known that MAP kinases are extracellular signal regulated kinases ERK1 and ERK2, which are components of the Ras-MAPK signal transduction pathway which is complexed with HDAC4 protein, and their inhibition is of significant therapeutic interest in cancer biology. In order to understand the mechanism of action, docking of indirubin class of molecules to the active site of histone deacetylase 4 (HDAC4) protein is performed, and the binding affinity of the protein-ligand interaction was computed. The new structural insights obtained from this study are all consistent with the available experimental data, suggesting that the homology model of the Leishmania MAPK and its ligand interaction modes are reasonable. Further the comparative molecular electrostatic potential and cavity depth analysis of Leishmania MAPK and human ERK2 suggested several important differences in its ATP binding pocket. Such differences could be exploited in the future for designing Leishmania specific MAPK inhibitors.
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Affiliation(s)
- Mahendra Awale
- National Institute of Pharmaceutical Education and Research, Nagar, Punjab, India
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41
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Modularity of MAP kinases allows deformation of their signalling pathways. Nat Cell Biol 2009; 11:484-91. [PMID: 19295513 DOI: 10.1038/ncb1856] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2008] [Accepted: 01/08/2009] [Indexed: 12/20/2022]
Abstract
Eukaryotic protein kinase pathways have both grown in number and changed their network architecture during evolution. We wondered if there are pivotal proteins in these pathways that have been repeatedly responsible for forming new connections through evolution, thus changing the topology of the network; and if so, whether the underlying properties of these proteins could be exploited to re-engineer and rewire these pathways. We addressed these questions in the context of the mitogen-activated protein kinase (MAPK) pathways. MAPK proteins were found to have repeatedly acquired new specificities and interaction partners during evolution, suggesting that these proteins are pivotal in the kinase network. Using the MAPKs Fus3 and Hog1 of the Saccharomyces cerevisiae mating and hyper-osmolar pathways, respectively, we show that these pivotal proteins can be re-designed to achieve a wide variety of changes in the input-output properties of the MAPK network. Through an analysis of our experimental results and of the sequence and structure of these proteins, we show that rewiring of the network is possible due to the underlying modular design of the MAPKs. We discuss the implications of our findings on the radiation of MAPKs through evolution and on how these proteins achieve their specificity.
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42
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Min X, Akella R, He H, Humphreys JM, Tsutakawa SE, Lee SJ, Tainer JA, Cobb MH, Goldsmith EJ. The structure of the MAP2K MEK6 reveals an autoinhibitory dimer. Structure 2009; 17:96-104. [PMID: 19141286 DOI: 10.1016/j.str.2008.11.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2008] [Revised: 10/10/2008] [Accepted: 11/13/2008] [Indexed: 12/17/2022]
Abstract
MAP2Ks are dual-specificity protein kinases functioning at the center of three-tiered MAP kinase modules. The structure of the kinase domain of the MAP2K MEK6 with phosphorylation site mimetic aspartic acid mutations (MEK6/DeltaN/DD) has been solved at 2.3 angstroms resolution. The structure reveals an autoinhibited elongated ellipsoidal dimer. The enzyme adopts an inactive conformation, based upon structural queues, despite the phosphomimetic mutations. Gel filtration and small-angle X-ray scattering analysis confirm that the crystallographically observed ellipsoidal dimer is a feature of MEK6/DeltaN/DD and full-length unphosphorylated wild-type MEK6 in solution. The interface includes the phosphate binding ribbon of each subunit, part of the activation loop, and a rare "arginine stack" between symmetry-related arginine residues in the N-terminal lobe. The autoinhibited structure likely confers specificity on active MAP2Ks. The dimer may also serve the function in unphosphorylated MEK6 of preventing activation loop phosphorylation by inappropriate kinases.
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Affiliation(s)
- Xiaoshan Min
- Department of Biochemistry, The University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Boulevard, Dallas, TX 75390-8816, USA
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Bardwell AJ, Frankson E, Bardwell L. Selectivity of docking sites in MAPK kinases. J Biol Chem 2009; 284:13165-73. [PMID: 19196711 DOI: 10.1074/jbc.m900080200] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Protein kinases often recognize their substrates and regulators through docking interactions that occur outside of the active site; these interactions can help us to understand kinase networks, and to target kinases with drugs. During mitogen-activated protein kinase (MAPK) signaling, the ability of MAPK kinases (MKKs, or MEKs) to recognize their cognate MAPKs is facilitated by a short docking motif (the D-site) in the MKK N terminus, which binds to a complementary region on the MAPK. MAPKs then recognize many of their targets using the same strategy, because many MAPK substrates also contain D-sites. The extent to which docking contributes to the specificity of MAPK transactions is incompletely understood. Here we characterize the selectivity of the interaction between MKK-derived D-sites and MAPKs by measuring the ability of D-site peptides to inhibit MAPK-mediated phosphorylation of D-site-containing substrates. We find that all MKK D-sites bind better to their cognate MAPKs than they do to non-cognate MAPKs. For instance, the MKK3 D-site peptide, which is a remarkably potent inhibitor of p38alpha (IC(50) < 10 nm), does not inhibit JNK1 or JNK2. Likewise, MAPKs generally bind as well or better to cognate D-sites than to non-cognate D-sites. For instance, JNK1 and JNK2 do not appreciably bind to any D-sites other than their cognate D-sites from MKK4 and MKK7. In general, cognate, within-pathway interactions are preferred about an order of magnitude over non-cognate interactions. However, the selectivity of MAPKs and their cognate MKK-derived D-sites for each other is limited in some cases; in particular, ERK2 is not very selective. We conclude that MAPK-docking sites in MAPK kinases bind selectively to their cognate MAPKs.
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Affiliation(s)
- A Jane Bardwell
- Department of Developmental and Cell Biology, University of California, Irvine, CA 92697-2300, USA
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Paz C, Poderoso C, Maloberti P, Maciel FC, Mendez C, Poderoso JJ, Podestá EJ. Chapter 10 Detection of a Mitochondrial Kinase Complex That Mediates PKA–MEK–ERK‐Dependent Phosphorylation of Mitochondrial Proteins Involved in the Regulation of Steroid Biosynthesis. Methods Enzymol 2009; 457:169-92. [DOI: 10.1016/s0076-6879(09)05010-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Miura K, Imaki J. Identification of ERK2-binding domain of EBITEIN1, a novel ERK2-binding protein. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2008; 1784:1319-25. [PMID: 18590835 DOI: 10.1016/j.bbapap.2008.05.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2008] [Revised: 04/24/2008] [Accepted: 05/27/2008] [Indexed: 12/12/2022]
Abstract
We recently cloned a cDNA encoding a novel extracellular signal-regulated kinase 2 (ERK2) binding protein, EBITEIN1, by yeast two-hybrid screening. In this study, we further characterized EBITEIN1. Binding experiments using various deletion mutants identified a 40-amino acid minimal sequence for binding ERK2. Binding experiments using substitution mutants indicated the crucial role of arginine residues in this sequence. Based on empirical and bioinformatic analyses, we propose two domains in EBITEIN1. One is the minimal sequence for binding ERK2 (EB domain) and the other is the EBITEIN1 C-terminal domain (ECT domain). These results might pave the way for further empirical and bioinformatic analyses of EBITEIN1- and ERK2-mediated events.
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Affiliation(s)
- Kenji Miura
- Department of Developmental Anatomy and Regenerative Biology, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama 359-8513, Japan.
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Ember B, Kamenecka T, LoGrasso P. Kinetic mechanism and inhibitor characterization for c-jun-N-terminal kinase 3alpha1. Biochemistry 2008; 47:3076-84. [PMID: 18269248 DOI: 10.1021/bi701852z] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
c-jun-N-Terminal kinase 3alpha1 (JNK3alpha1) is a mitogen-activated protein (MAP) kinase family member expressed primarily in the brain that phosphorylates protein transcription factors including c-jun and activating transcription factor 2 (ATF2) upon activation by a variety of stress-based stimuli. In this study, the kinetic mechanism for JNK3alpha1 was determined via initial velocity patterns in the presence and absence of both ATP and ATF2 competitive inhibitors. Peptide inhibitors from both ATF2 (peptide 1) and JNK-interacting protein 1 (JIP-1) (peptide 3), derived from the homologous delta-domain JNK docking sequence, inhibited JNK3alpha1 activity in a competitive fashion versus ATF2 while being pure noncompetitive toward ATP. In contrast, peptides derived from the phosphoacceptor activation domain on ATF2 (peptides 4 and 5) were recognized neither as substrates nor as inhibitors of JNK3alpha1. AMP-PCP and compound 6, a small molecule analinopyrimidine, exhibited pure noncompetitive inhibition versus ATF2 and competitive inhibition versus ATP. Peptide inhibitors based on the delta-domain sites of JIP ( 3) and ATF2 ( 1) were not recognized by p38, also of the MAPK family, which may give insight into finding more selective inhibitors for the JNK family of kinases. Collectively these data showed that JNK3alpha1 proceeded by a random sequential kinetic mechanism and that the ATP and ATF2 substrate sites were non-interacting. Moreover, these results established the 11-mer JIP peptide ( 3) as a potent ( K i = 25 +/- 6 nM) competitive inhibitor versus ATF2 in JNK3alpha1.
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Affiliation(s)
- Brian Ember
- Department of Molecular Therapeutics and Drug Discovery, The Scripps Research Institute, Scripps Florida, 5353 Parkside Drive, Jupiter, Florida 33458, USA
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Miura K, Imaki J. Molecular cloning of Ebitein1: a novel extracellular signal-regulated kinase 2-binding protein in testis. Biochem Biophys Res Commun 2008; 368:336-42. [PMID: 18241670 DOI: 10.1016/j.bbrc.2008.01.078] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2007] [Accepted: 01/16/2008] [Indexed: 11/28/2022]
Abstract
We cloned a cDNA encoding a novel extracellular signal-regulated kinase (ERK) 2-binding protein, EBITEIN1, by yeast two-hybrid screening. Northern and Western blotting experiments showed that the transcript and protein were expressed in the testes. Furthermore, immunohistochemical experiments showed that EBITEIN1 existed at high levels in round spermatids, but at very low levels or not at all in other testicular cells. During spermatogenesis, EBITEIN1 was first translated after meiosis when cells became haploid, then the amount of EBITEIN1 protein gradually increased, reaching a maximum at Oakberg's stage 9. Subsequently, the level of EBITEIN1 decreased such that it was undetectable when the flagellum of the spermatozoon was generated. On a subcellular level, EBITEIN1 localized in the cytoplasm. Based on these results, we propose that EBITEIN1 is an interactor of ERK2 in the intracellular signal transduction pathway that occurs during the morphogenetic development of round spermatids to spermatozoa. The existence of this novel ERK2-interactor indicates that there could be a novel intracellular signaling pathway and/or regulatory mechanism by which ERK2 regulates intracellular events.
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Affiliation(s)
- Kenji Miura
- Department of Developmental Anatomy and Regenerative Biology, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama 359-8513, Japan.
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A mitochondrial kinase complex is essential to mediate an ERK1/2-dependent phosphorylation of a key regulatory protein in steroid biosynthesis. PLoS One 2008; 3:e1443. [PMID: 18197253 PMCID: PMC2175533 DOI: 10.1371/journal.pone.0001443] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2007] [Accepted: 12/13/2007] [Indexed: 12/03/2022] Open
Abstract
ERK1/2 is known to be involved in hormone-stimulated steroid synthesis, but its exact roles and the underlying mechanisms remain elusive. Both ERK1/2 phosphorylation and steroidogenesis may be triggered by cAMP/cAMP-dependent protein kinase (PKA)-dependent and-independent mechanisms; however, ERK1/2 activation by cAMP results in a maximal steroidogenic rate, whereas canonical activation by epidermal growth factor (EGF) does not. We demonstrate herein by Western blot analysis and confocal studies that temporal mitochondrial ERK1/2 activation is obligatory for PKA-mediated steroidogenesis in the Leydig-transformed MA-10 cell line. PKA activity leads to the phosphorylation of a constitutive mitochondrial MEK1/2 pool with a lower effect in cytosolic MEKs, while EGF allows predominant cytosolic MEK activation and nuclear pERK1/2 localization. These results would explain why PKA favors a more durable ERK1/2 activation in mitochondria than does EGF. By means of ex vivo experiments, we showed that mitochondrial maximal steroidogenesis occurred as a result of the mutual action of steroidogenic acute regulatory (StAR) protein –a key regulatory component in steroid biosynthesis-, active ERK1/2 and PKA. Our results indicate that there is an interaction between mitochondrial StAR and ERK1/2, involving a D domain with sequential basic-hydrophobic motifs similar to ERK substrates. As a result of this binding and only in the presence of cholesterol, ERK1/2 phosphorylates StAR at Ser232. Directed mutagenesis of Ser232 to a non-phosphorylable amino acid such as Ala (StAR S232A) inhibited in vitro StAR phosphorylation by active ERK1/2. Transient transfection of MA-10 cells with StAR S232A markedly reduced the yield of progesterone production. In summary, here we show that StAR is a novel substrate of ERK1/2, and that mitochondrial ERK1/2 is part of a multimeric protein kinase complex that regulates cholesterol transport. The role of MAPKs in mitochondrial function is underlined.
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Fernandes N, Bailey DE, Vanvranken DL, Allbritton NL. Use of docking peptides to design modular substrates with high efficiency for mitogen-activated protein kinase extracellular signal-regulated kinase. ACS Chem Biol 2007; 2:665-73. [PMID: 17918909 PMCID: PMC2597387 DOI: 10.1021/cb700158q] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The mitogen-activated protein kinase extracellular regulated kinase (ERK) plays a key role in the regulation of cellular proliferation. Mutations in the ERK cascade occur in 30% of malignant tumors. Thus understanding how the kinase identifies its cognate substrates as well as monitoring the activity of ERK is central to cancer research and therapeutic development. ERK binds to its protein targets, both downstream substrates and upstream activators, via a binding site distinct from the catalytic site of ERK. The substrate sequences that bind, or dock, to these sites on ERK influence the efficiency of phosphorylation. For this reason, simple peptide substrates containing only phosphorylation sequences typically possess low efficiencies for ERK. Appending short docking peptides derived from full-length protein substrates and activators of ERK to a phosphorylation sequence increased the affinity of ERK for the phosphorylation sequence by as much as 200-fold while only slightly diminishing the maximal velocity of the reaction. The efficiency of the phosphorylation reaction was increased by up to 150-fold, while the specificity of the substrate for ERK was preserved. Simple modular peptide substrates, which can be easily tailored to possess high phosphorylation efficiencies, will enhance our understanding of the regulation of ERK and provide a tool for the development of new kinase assays.
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Affiliation(s)
- Neychelle Fernandes
- Department of Chemical Engineering and Materials Science, University of California, Irvine, California 92697, USA
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Nordle AKL, Rios P, Gaulton A, Pulido R, Attwood TK, Tabernero L. Functional assignment of MAPK phosphatase domains. Proteins 2007; 69:19-31. [PMID: 17596826 DOI: 10.1002/prot.21477] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Mitogen-activated protein kinase (MAPK) pathways are well conserved in most organisms, from yeast to humans. The principal components of these pathways are MAP kinases whose activity is regulated by phosphorylation, implicating various MAPK protein effectors-in particular, protein phosphatases that inactivate MAPKs by dephosphorylation. The molecular basis of binding specificity of such regulatory phosphatases to MAPKs is poorly understood. To try to pinpoint potential functional regions within the sequences and to help identify new family members, we have applied a multimotif pattern-recognition approach to characterize two MAPK phosphatase subfamilies (tyrosine-specific and dual specificity) that are crucial in the regulation of MAPKs. We built "fingerprints" for these two subfamilies that are unique to, and highly discriminatory for, each group of proteins. The fingerprints were used in a genome-wide screen, identifying more than 80 MAPK phosphatase domains, several of which were in partial sequences or unclassified proteins. We confirmed experimentally that one predicted MAPK phosphatase orthologue in Xenopus binds to ERK1/2, suggesting a role in MAPK signaling and thus supporting our functional predictions. Further analysis, mapping the fingerprints on the three-dimensional structure of MAPK phosphatases, revealed that some of the fingerprint motifs reside in the N-terminal noncatalytic regions coinciding with reported MAPK binding sites, while others lie within the catalytic phosphatase domain. These results also suggest the presence of putative allosteric sites in the catalytic region for modulation of protein-protein interactions, and provide a framework for future experimental validation.
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Affiliation(s)
- Anna K L Nordle
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
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