1
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Rivoire O. A role for conformational changes in enzyme catalysis. Biophys J 2024; 123:1563-1578. [PMID: 38704639 PMCID: PMC11213973 DOI: 10.1016/j.bpj.2024.04.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 04/15/2024] [Accepted: 04/29/2024] [Indexed: 05/06/2024] Open
Abstract
The role played by conformational changes in enzyme catalysis is controversial. In addition to examining specific enzymes, studying formal models can help identify the conditions under which conformational changes promote catalysis. Here, we present a model demonstrating how conformational changes can break a generic trade-off due to the conflicting requirements of successive steps in catalytic cycles, namely high specificity for the transition state to accelerate the chemical transformation and low affinity for the products to favor their release. The mechanism by which the trade-off is broken is a transition between conformations with different affinities for the substrate. The role of the effector that induces the transition is played by a substrate "handle," a part of the substrate that is not chemically transformed but whose interaction with the enzyme is nevertheless essential to rapidly complete the catalytic cycle. A key element of the model is the formalization of the constraints causing the trade-off that the presence of multiple states breaks, which we attribute to the strong chemical similarity between successive reaction states-substrates, transition states, and products. For the sake of clarity, we present our model for irreversible one-step unimolecular reactions. In this context, we demonstrate how the different forms that chemical similarities between reaction states can take impose limits on the overall catalytic turnover. We first analyze catalysts without internal degrees of freedom and then show how two-state catalysts can overcome their limitations. Our results recapitulate previous proposals concerning the role of conformational changes and substrate handles in a formalism that makes explicit the constraints that elicit these features. In addition, our approach establishes links with studies in the field of heterogeneous catalysis, where the same trade-offs are observed and where overcoming them is a well-recognized challenge.
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2
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Liu GY, Jouandin P, Bahng RE, Perrimon N, Sabatini DM. An evolutionary mechanism to assimilate new nutrient sensors into the mTORC1 pathway. Nat Commun 2024; 15:2517. [PMID: 38514639 PMCID: PMC10957897 DOI: 10.1038/s41467-024-46680-3] [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: 05/15/2023] [Accepted: 03/06/2024] [Indexed: 03/23/2024] Open
Abstract
Animals sense and respond to nutrient availability in their environments, a task coordinated in part by the mTOR complex 1 (mTORC1) pathway. mTORC1 regulates growth in response to nutrients and, in mammals, senses specific amino acids through specialized sensors that bind the GATOR1/2 signaling hub. Given that animals can occupy diverse niches, we hypothesized that the pathway might evolve distinct sensors in different metazoan phyla. Whether such customization occurs, and how the mTORC1 pathway might capture new inputs, is unknown. Here, we identify the Drosophila melanogaster protein Unmet expectations (CG11596) as a species-restricted methionine sensor that directly binds the fly GATOR2 complex in a fashion antagonized by S-adenosylmethionine (SAM). We find that in Dipterans GATOR2 rapidly evolved the capacity to bind Unmet and to thereby repurpose a previously independent methyltransferase as a SAM sensor. Thus, the modular architecture of the mTORC1 pathway allows it to co-opt preexisting enzymes to expand its nutrient sensing capabilities, revealing a mechanism for conferring evolvability on an otherwise conserved system.
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Affiliation(s)
- Grace Y Liu
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Department of Biology, 455 Main Street, Cambridge, MA, USA.
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, USA.
- Koch Institute for Integrative Cancer Research and Massachusetts Institute of Technology, Department of Biology, 77 Massachusetts Avenue, Cambridge, MA, USA.
| | - Patrick Jouandin
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA
- Institut de Recherche en Cancérologie de Montpellier, Inserm U1194-UM-ICM, Campus Val d'Aurelle, Montpellier, Cedex 5, France
| | - Raymond E Bahng
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Department of Biology, 455 Main Street, Cambridge, MA, USA
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, USA
- Koch Institute for Integrative Cancer Research and Massachusetts Institute of Technology, Department of Biology, 77 Massachusetts Avenue, Cambridge, MA, USA
| | - Norbert Perrimon
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA.
- Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA.
| | - David M Sabatini
- Institute of Organic Chemistry and Biochemistry, Flemingovo n. 2, 166 10 Praha 6, Prague, Czech Republic.
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3
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Mathy CJP, Kortemme T. Emerging maps of allosteric regulation in cellular networks. Curr Opin Struct Biol 2023; 80:102602. [PMID: 37150039 PMCID: PMC10960510 DOI: 10.1016/j.sbi.2023.102602] [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: 12/29/2022] [Revised: 03/24/2023] [Accepted: 04/04/2023] [Indexed: 05/09/2023]
Abstract
Allosteric regulation is classically defined as action at a distance, where a perturbation outside of a protein active site affects function. While this definition has motivated many studies of allosteric mechanisms at the level of protein structure, translating these insights to the allosteric regulation of entire cellular processes - and their crosstalk - has received less attention, despite the broad importance of allostery for cellular regulation foreseen by Jacob and Monod. Here, we revisit an evolutionary model for the widespread emergence of allosteric regulation in colocalized proteins, describe supporting evidence, and discuss emerging advances in mapping allostery in cellular networks that link precise and often allosteric perturbations at the molecular level to functional changes at the pathway and systems levels.
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Affiliation(s)
- Christopher J P Mathy
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, 94158, USA; Quantitative Biosciences Institute, University of California, San Francisco, CA, 94158, USA; The UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, San Francisco, CA, 94158, USA.
| | - Tanja Kortemme
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, 94158, USA; Quantitative Biosciences Institute, University of California, San Francisco, CA, 94158, USA; The UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, San Francisco, CA, 94158, USA; Chan Zuckerberg Biohub, San Francisco, CA, 94158, USA.
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4
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Liu GY, Jouandin P, Bahng RE, Perrimon N, Sabatini DM. An evolutionary mechanism to assimilate new nutrient sensors into the mTORC1 pathway. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.25.541239. [PMID: 37292894 PMCID: PMC10245982 DOI: 10.1101/2023.05.25.541239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Animals must sense and respond to nutrient availability in their local niche. This task is coordinated in part by the mTOR complex 1 (mTORC1) pathway, which regulates growth and metabolism in response to nutrients1-5. In mammals, mTORC1 senses specific amino acids through specialized sensors that act through the upstream GATOR1/2 signaling hub6-8. To reconcile the conserved architecture of the mTORC1 pathway with the diversity of environments that animals can occupy, we hypothesized that the pathway might maintain plasticity by evolving distinct nutrient sensors in different metazoan phyla1,9,10. Whether such customization occurs-and how the mTORC1 pathway might capture new nutrient inputs-is not known. Here, we identify the Drosophila melanogaster protein Unmet expectations (Unmet, formerly CG11596) as a species-restricted nutrient sensor and trace its incorporation into the mTORC1 pathway. Upon methionine starvation, Unmet binds to the fly GATOR2 complex to inhibit dTORC1. S-adenosylmethionine (SAM), a proxy for methionine availability, directly relieves this inhibition. Unmet expression is elevated in the ovary, a methionine-sensitive niche11, and flies lacking Unmet fail to maintain the integrity of the female germline under methionine restriction. By monitoring the evolutionary history of the Unmet-GATOR2 interaction, we show that the GATOR2 complex evolved rapidly in Dipterans to recruit and repurpose an independent methyltransferase as a SAM sensor. Thus, the modular architecture of the mTORC1 pathway allows it to co-opt preexisting enzymes and expand its nutrient sensing capabilities, revealing a mechanism for conferring evolvability on an otherwise highly conserved system.
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Affiliation(s)
- Grace Y. Liu
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Department of Biology; 455 Main Street, Cambridge, Massachusetts 02142, USA
- Department of Biology, Massachusetts Institute of Technology; 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA
- Koch Institute for Integrative Cancer Research and Massachusetts Institute of Technology, Department of Biology; 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA
| | - Patrick Jouandin
- Department of Genetics, Blavatnik Institute, Harvard Medical School; Boston, MA 02115, USA
- Howard Hughes Medical Institute, Harvard Medical School; Boston, MA 02115, USA
- Present address: Institut de Recherche en Cancérologie de Montpellier, Inserm U1194-UM-ICM; Campus Val d’Aurelle, F-34298 Montpellier Cedex 5, France
| | - Raymond E. Bahng
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Department of Biology; 455 Main Street, Cambridge, Massachusetts 02142, USA
- Department of Biology, Massachusetts Institute of Technology; 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA
- Koch Institute for Integrative Cancer Research and Massachusetts Institute of Technology, Department of Biology; 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA
| | - Norbert Perrimon
- Department of Genetics, Blavatnik Institute, Harvard Medical School; Boston, MA 02115, USA
- Howard Hughes Medical Institute, Harvard Medical School; Boston, MA 02115, USA
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5
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Steube N, Moldenhauer M, Weiland P, Saman D, Kilb A, Ramírez Rojas AA, Garg SG, Schindler D, Graumann PL, Benesch JLP, Bange G, Friedrich T, Hochberg GKA. Fortuitously compatible protein surfaces primed allosteric control in cyanobacterial photoprotection. Nat Ecol Evol 2023; 7:756-767. [PMID: 37012377 PMCID: PMC10172135 DOI: 10.1038/s41559-023-02018-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 02/21/2023] [Indexed: 04/05/2023]
Abstract
Highly specific interactions between proteins are a fundamental prerequisite for life, but how they evolve remains an unsolved problem. In particular, interactions between initially unrelated proteins require that they evolve matching surfaces. It is unclear whether such surface compatibilities can only be built by selection in small incremental steps, or whether they can also emerge fortuitously. Here, we used molecular phylogenetics, ancestral sequence reconstruction and biophysical characterization of resurrected proteins to retrace the evolution of an allosteric interaction between two proteins that act in the cyanobacterial photoprotection system. We show that this interaction between the orange carotenoid protein (OCP) and its unrelated regulator, the fluorescence recovery protein (FRP), evolved when a precursor of FRP was horizontally acquired by cyanobacteria. FRP's precursors could already interact with and regulate OCP even before these proteins first encountered each other in an ancestral cyanobacterium. The OCP-FRP interaction exploits an ancient dimer interface in OCP, which also predates the recruitment of FRP into the photoprotection system. Together, our work shows how evolution can fashion complex regulatory systems easily out of pre-existing components.
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Affiliation(s)
- Niklas Steube
- Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Marcus Moldenhauer
- Institute of Chemistry PC14, Technische Universität Berlin, Berlin, Germany
| | - Paul Weiland
- Department of Chemistry, University of Marburg, Marburg, Germany
- Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany
| | - Dominik Saman
- Department of Chemistry, Oxford University, Oxford, UK
- Kavli Institute for Nanoscience Discovery, Oxford University, Oxford, UK
| | - Alexandra Kilb
- Department of Chemistry, University of Marburg, Marburg, Germany
- Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany
| | | | - Sriram G Garg
- Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Daniel Schindler
- Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
- Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany
| | - Peter L Graumann
- Department of Chemistry, University of Marburg, Marburg, Germany
- Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany
| | - Justin L P Benesch
- Department of Chemistry, Oxford University, Oxford, UK
- Kavli Institute for Nanoscience Discovery, Oxford University, Oxford, UK
| | - Gert Bange
- Department of Chemistry, University of Marburg, Marburg, Germany
- Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany
| | - Thomas Friedrich
- Institute of Chemistry PC14, Technische Universität Berlin, Berlin, Germany.
| | - Georg K A Hochberg
- Max Planck Institute for Terrestrial Microbiology, Marburg, Germany.
- Department of Chemistry, University of Marburg, Marburg, Germany.
- Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany.
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6
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Pillai AS, Hochberg GK, Thornton JW. Simple mechanisms for the evolution of protein complexity. Protein Sci 2022; 31:e4449. [PMID: 36107026 PMCID: PMC9601886 DOI: 10.1002/pro.4449] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 09/01/2022] [Accepted: 09/10/2022] [Indexed: 01/26/2023]
Abstract
Proteins are tiny models of biological complexity: specific interactions among their many amino acids cause proteins to fold into elaborate structures, assemble with other proteins into higher-order complexes, and change their functions and structures upon binding other molecules. These complex features are classically thought to evolve via long and gradual trajectories driven by persistent natural selection. But a growing body of evidence from biochemistry, protein engineering, and molecular evolution shows that naturally occurring proteins often exist at or near the genetic edge of multimerization, allostery, and even new folds, so just one or a few mutations can trigger acquisition of these properties. These sudden transitions can occur because many of the physical properties that underlie these features are present in simpler proteins as fortuitous by-products of their architecture. Moreover, complex features of proteins can be encoded by huge arrays of sequences, so they are accessible from many different starting points via many possible paths. Because the bridges to these features are both short and numerous, random chance can join selection as a key factor in explaining the evolution of molecular complexity.
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Affiliation(s)
- Arvind S. Pillai
- Department of Ecology and EvolutionUniversity of ChicagoChicagoIllinoisUSA
- Institute for Protein DesignUniversity of WashingtonSeattleWAUSA
| | - Georg K.A. Hochberg
- Max Planck Institute for Terrestrial MicrobiologyMarburgGermany
- Department of Chemistry, Center for Synthetic MicrobiologyPhilipps University MarburgMarburgGermany
| | - Joseph W. Thornton
- Department of Ecology and EvolutionUniversity of ChicagoChicagoIllinoisUSA
- Departments of Human Genetics and Ecology and EvolutionUniversity of ChicagoChicagoIllinoisUSA
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7
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Iorio A, Brochier-Armanet C, Mas C, Sterpone F, Madern D. Protein Conformational Space at the Edge of Allostery: Turning a Non-allosteric Malate Dehydrogenase into an "Allosterized" Enzyme using Evolution Guided Punctual Mutations. Mol Biol Evol 2022; 39:6691310. [PMID: 36056899 PMCID: PMC9486893 DOI: 10.1093/molbev/msac186] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We unveil the intimate relationship between protein dynamics and allostery by following the trajectories of model proteins in their conformational and sequence spaces. Starting from a nonallosteric hyperthermophilic malate dehydrogenase, we have tracked the role of protein dynamics in the evolution of the allosteric capacity. Based on a large phylogenetic analysis of the malate (MalDH) and lactate dehydrogenase (LDH) superfamily, we identified two amino acid positions that could have had a major role for the emergence of allostery in LDHs, which we targeted for investigation by site-directed mutagenesis. Wild-type MalDH and the single and double mutants were tested with respect to their substrate recognition profiles. The double mutant displayed a sigmoid-shaped profile typical of homotropic activation in LDH. By using molecular dynamics simulations, we showed that the mutations induce a drastic change in the protein sampling of its conformational landscape, making transiently T-like (inactive) conformers, typical of allosteric LDHs, accessible. Our data fit well with the seminal key concept linking protein dynamics and evolvability. We showed that the selection of a new phenotype can be achieved by a few key dynamics-enhancing mutations causing the enrichment of low-populated conformational substates.
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Affiliation(s)
- Antonio Iorio
- CNRS, Université de Paris, UPR 9080, Laboratoire de Biochimie Théorique, Paris, France; Institut de Biologie Physico-Chimique-Fondation Edmond de Rothschild, PSL Research University, Paris, France
| | - Céline Brochier-Armanet
- Univ Lyon, Université Lyon 1, CNRS, UMR5558, Laboratoire de Biométrie et Biologie Évolutive, 43 bd du 11 novembre 1918, F-69622, Villeurbanne, France
| | - Caroline Mas
- Univ. Grenoble Alpes, CEA, CNRS, IBS, 38000 Grenoble, France
| | - Fabio Sterpone
- CNRS, Université de Paris, UPR 9080, Laboratoire de Biochimie Théorique, Paris, France; Institut de Biologie Physico-Chimique-Fondation Edmond de Rothschild, PSL Research University, Paris, France
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8
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Jayaraman V, Toledo‐Patiño S, Noda‐García L, Laurino P. Mechanisms of protein evolution. Protein Sci 2022; 31:e4362. [PMID: 35762715 PMCID: PMC9214755 DOI: 10.1002/pro.4362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 05/11/2022] [Accepted: 05/14/2022] [Indexed: 11/06/2022]
Abstract
How do proteins evolve? How do changes in sequence mediate changes in protein structure, and in turn in function? This question has multiple angles, ranging from biochemistry and biophysics to evolutionary biology. This review provides a brief integrated view of some key mechanistic aspects of protein evolution. First, we explain how protein evolution is primarily driven by randomly acquired genetic mutations and selection for function, and how these mutations can even give rise to completely new folds. Then, we also comment on how phenotypic protein variability, including promiscuity, transcriptional and translational errors, may also accelerate this process, possibly via "plasticity-first" mechanisms. Finally, we highlight open questions in the field of protein evolution, with respect to the emergence of more sophisticated protein systems such as protein complexes, pathways, and the emergence of pre-LUCA enzymes.
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Affiliation(s)
- Vijay Jayaraman
- Department of Molecular Cell BiologyWeizmann Institute of ScienceRehovotIsrael
| | - Saacnicteh Toledo‐Patiño
- Protein Engineering and Evolution UnitOkinawa Institute of Science and Technology Graduate UniversityOkinawaJapan
| | - Lianet Noda‐García
- Department of Plant Pathology and Microbiology, Institute of Environmental Sciences, Robert H. Smith Faculty of Agriculture, Food and EnvironmentHebrew University of JerusalemRehovotIsrael
| | - Paola Laurino
- Protein Engineering and Evolution UnitOkinawa Institute of Science and Technology Graduate UniversityOkinawaJapan
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9
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Coyote-Maestas W, Nedrud D, Suma A, He Y, Matreyek KA, Fowler DM, Carnevale V, Myers CL, Schmidt D. Probing ion channel functional architecture and domain recombination compatibility by massively parallel domain insertion profiling. Nat Commun 2021; 12:7114. [PMID: 34880224 PMCID: PMC8654947 DOI: 10.1038/s41467-021-27342-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 11/16/2021] [Indexed: 11/10/2022] Open
Abstract
Protein domains are the basic units of protein structure and function. Comparative analysis of genomes and proteomes showed that domain recombination is a main driver of multidomain protein functional diversification and some of the constraining genomic mechanisms are known. Much less is known about biophysical mechanisms that determine whether protein domains can be combined into viable protein folds. Here, we use massively parallel insertional mutagenesis to determine compatibility of over 300,000 domain recombination variants of the Inward Rectifier K+ channel Kir2.1 with channel surface expression. Our data suggest that genomic and biophysical mechanisms acted in concert to favor gain of large, structured domain at protein termini during ion channel evolution. We use machine learning to build a quantitative biophysical model of domain compatibility in Kir2.1 that allows us to derive rudimentary rules for designing domain insertion variants that fold and traffic to the cell surface. Positional Kir2.1 responses to motif insertion clusters into distinct groups that correspond to contiguous structural regions of the channel with distinct biophysical properties tuned towards providing either folding stability or gating transitions. This suggests that insertional profiling is a high-throughput method to annotate function of ion channel structural regions.
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Affiliation(s)
- Willow Coyote-Maestas
- grid.17635.360000000419368657Department of Biochemistry, Molecular Biology & Biophysics, University of Minnesota, Minneapolis, MN 55455 USA
| | - David Nedrud
- grid.17635.360000000419368657Department of Biochemistry, Molecular Biology & Biophysics, University of Minnesota, Minneapolis, MN 55455 USA
| | - Antonio Suma
- grid.264727.20000 0001 2248 3398Department of Chemistry, Temple University, Philadelphia, PA 19122 USA
| | - Yungui He
- grid.17635.360000000419368657Department of Genetics, Cell Biology & Development, University of Minnesota, Minneapolis, MN 55455 USA
| | - Kenneth A. Matreyek
- grid.67105.350000 0001 2164 3847Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, OH 44106 USA
| | - Douglas M. Fowler
- grid.34477.330000000122986657Department of Genome Sciences, University of Washington, Seattle, WA 98115 USA ,grid.34477.330000000122986657Department of Bioengineering, University of Washington, Seattle, WA 98115 USA
| | - Vincenzo Carnevale
- grid.264727.20000 0001 2248 3398Department of Chemistry, Temple University, Philadelphia, PA 19122 USA
| | - Chad L. Myers
- grid.17635.360000000419368657Department of Computer Science and Engineering, University of Minnesota, Minneapolis, MN 55455 USA
| | - Daniel Schmidt
- Department of Genetics, Cell Biology & Development, University of Minnesota, Minneapolis, MN, 55455, USA.
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10
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Verkhivker GM. Making the invisible visible: Toward structural characterization of allosteric states, interaction networks, and allosteric regulatory mechanisms in protein kinases. Curr Opin Struct Biol 2021; 71:71-78. [PMID: 34237520 DOI: 10.1016/j.sbi.2021.06.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 05/27/2021] [Accepted: 06/03/2021] [Indexed: 02/07/2023]
Abstract
Despite the established view of protein kinases as dynamic and versatile allosteric regulatory machines, our knowledge of allosteric functional states, allosteric interaction networks, and the intrinsic folding energy landscapes is surprisingly limited. We discuss the latest developments in structural characterization of allosteric molecular events underlying protein kinase dynamics and functions using structural, biophysical, and computational biology approaches. The recent studies highlighted progress in making the invisible aspects of protein kinase 'life' visible, including the determination of hidden allosteric states and mapping of allosteric energy landscapes, discovery of new mechanisms underlying ligand-induced modulation of allosteric activity, evolutionary adaptation of kinase allostery, and characterization of allosteric interaction networks as the intrinsic driver of kinase adaptability and signal transmission in the regulatory assemblies.
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Affiliation(s)
- Gennady M Verkhivker
- Keck Center for Science and Engineering, Schmid College of Science and Technology, Chapman University, One University Drive, Orange, CA, 92866, USA; Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, 9401 Jeronimo Road, Irvine, CA, 92618, USA.
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11
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Pack LR, Daigh LH, Chung M, Meyer T. Clinical CDK4/6 inhibitors induce selective and immediate dissociation of p21 from cyclin D-CDK4 to inhibit CDK2. Nat Commun 2021; 12:3356. [PMID: 34099663 PMCID: PMC8184839 DOI: 10.1038/s41467-021-23612-z] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 05/06/2021] [Indexed: 12/11/2022] Open
Abstract
Since their discovery as drivers of proliferation, cyclin-dependent kinases (CDKs) have been considered therapeutic targets. Small molecule inhibitors of CDK4/6 are used and tested in clinical trials to treat multiple cancer types. Despite their clinical importance, little is known about how CDK4/6 inhibitors affect the stability of CDK4/6 complexes, which bind cyclins and inhibitory proteins such as p21. We develop an assay to monitor CDK complex stability inside the nucleus. Unexpectedly, treatment with CDK4/6 inhibitors-palbociclib, ribociclib, or abemaciclib-immediately dissociates p21 selectively from CDK4 but not CDK6 complexes. This effect mediates indirect inhibition of CDK2 activity by p21 but not p27 redistribution. Our work shows that CDK4/6 inhibitors have two roles: non-catalytic inhibition of CDK2 via p21 displacement from CDK4 complexes, and catalytic inhibition of CDK4/6 independent of p21. By broadening the non-catalytic displacement to p27 and CDK6 containing complexes, next-generation CDK4/6 inhibitors may have improved efficacy and overcome resistance mechanisms.
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Affiliation(s)
- Lindsey R Pack
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
| | - Leighton H Daigh
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
| | - Mingyu Chung
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
| | - Tobias Meyer
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA.
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12
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Abstract
Most proteins associate into multimeric complexes with specific architectures1,2, which often have functional properties like cooperative ligand binding or allosteric regulation3. No detailed knowledge is available about how any multimer and its functions arose during historical evolution. Here we use ancestral protein reconstruction and biophysical assays to dissect the origins of vertebrate hemoglobin (Hb), a heterotetramer of paralogous α and β subunits, which mediates respiratory oxygen transport and exchange by cooperatively binding oxygen with moderate affinity. We show that modern Hb evolved from an ancient monomer and characterize the historical “missing-link” through which the modern tetramer evolved–a noncooperative homodimer with high oxygen affinity, which existed before the gene duplication that generated distinct α and β subunits. Reintroducing just two post-duplication historical substitutions into the ancestral protein is sufficient to cause strong tetramerization by creating favorable contacts with more ancient residues on the opposing subunit. These surface substitutions dramatically reduce oxygen affinity and even confer weak cooperativity, because of an ancient structural linkage between the oxygen binding site and the multimerization interface. Our findings establish that evolution can produce new complex molecular structures and functions via simple genetic mechanisms, which recruit existing biophysical features into higher-level architectures.
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13
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Hadzipasic A, Wilson C, Nguyen V, Kern N, Kim C, Pitsawong W, Villali J, Zheng Y, Kern D. Ancient origins of allosteric activation in a Ser-Thr kinase. Science 2020; 367:912-917. [PMID: 32079772 DOI: 10.1126/science.aay9959] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Revised: 12/09/2019] [Accepted: 01/15/2020] [Indexed: 12/23/2022]
Abstract
A myriad of cellular events are regulated by allostery; therefore, evolution of this process is of fundamental interest. Here, we use ancestral sequence reconstruction to resurrect ancestors of two colocalizing proteins, Aurora A kinase and its allosteric activator TPX2 (targeting protein for Xklp2), to experimentally characterize the evolutionary path of allosteric activation. Autophosphorylation of the activation loop is the most ancient activation mechanism; it is fully developed in the oldest kinase ancestor and has remained stable over 1 billion years of evolution. As the microtubule-associated protein TPX2 appeared, efficient kinase binding to TPX2 evolved, likely owing to increased fitness by virtue of colocalization. Subsequently, TPX2-mediated allosteric kinase regulation gradually evolved. Surprisingly, evolution of this regulation is encoded in the kinase and did not arise by a dominating mechanism of coevolution.
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Affiliation(s)
- Adelajda Hadzipasic
- Department of Biochemistry, Brandeis University, Waltham, MA 02454, USA.,Howard Hughes Medical Institute, Brandeis University, Waltham, MA 02454, USA
| | - Christopher Wilson
- Department of Biochemistry, Brandeis University, Waltham, MA 02454, USA.,Howard Hughes Medical Institute, Brandeis University, Waltham, MA 02454, USA
| | - Vy Nguyen
- Department of Biochemistry, Brandeis University, Waltham, MA 02454, USA.,Howard Hughes Medical Institute, Brandeis University, Waltham, MA 02454, USA
| | - Nadja Kern
- Department of Biochemistry, Brandeis University, Waltham, MA 02454, USA.,Howard Hughes Medical Institute, Brandeis University, Waltham, MA 02454, USA
| | - Chansik Kim
- Department of Biochemistry, Brandeis University, Waltham, MA 02454, USA.,Howard Hughes Medical Institute, Brandeis University, Waltham, MA 02454, USA
| | - Warintra Pitsawong
- Department of Biochemistry, Brandeis University, Waltham, MA 02454, USA.,Howard Hughes Medical Institute, Brandeis University, Waltham, MA 02454, USA
| | - Janice Villali
- Department of Biochemistry, Brandeis University, Waltham, MA 02454, USA.,Howard Hughes Medical Institute, Brandeis University, Waltham, MA 02454, USA
| | - Yuejiao Zheng
- Department of Biochemistry, Brandeis University, Waltham, MA 02454, USA.,Howard Hughes Medical Institute, Brandeis University, Waltham, MA 02454, USA
| | - Dorothee Kern
- Department of Biochemistry, Brandeis University, Waltham, MA 02454, USA. .,Howard Hughes Medical Institute, Brandeis University, Waltham, MA 02454, USA
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14
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Bhat AS, Dustin Schaeffer R, Kinch L, Medvedev KE, Grishin NV. Recent advances suggest increased influence of selective pressure in allostery. Curr Opin Struct Biol 2020; 62:183-188. [PMID: 32302874 DOI: 10.1016/j.sbi.2020.02.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 02/21/2020] [Accepted: 02/25/2020] [Indexed: 12/19/2022]
Abstract
Allosteric regulation of protein functions is ubiquitous in organismal biology, but the principles governing its evolution are not well understood. Here we discuss recent studies supporting the large-scale existence of latent allostery in ancestor proteins of superfamilies. As suggested, the evolution of allostery could be driven by the need for specificity in paralogs of slow evolving protein complexes with conserved active sites. The same slow evolution is displayed by purifying selection exhibited in allosteric proteins with somatic mutations involved in cancer, where disease-associated mutations are enriched in both orthosteric and allosteric sites. Consequently, disease-associated variants can be used to identify druggable allosteric sites that are specific for paralogs in protein superfamilies with otherwise similar functions.
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Affiliation(s)
- Archana S Bhat
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390-9050, United States
| | - Richard Dustin Schaeffer
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390-9050, United States
| | - Lisa Kinch
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390-9050, United States
| | - Kirill E Medvedev
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390-9050, United States
| | - Nick V Grishin
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390-9050, United States; Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390-9050, United States.
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15
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Trevelyan SJ, Brewster JL, Burgess AE, Crowther JM, Cadell AL, Parker BL, Croucher DR, Dobson RCJ, Murphy JM, Mace PD. Structure-based mechanism of preferential complex formation by apoptosis signal–regulating kinases. Sci Signal 2020; 13:13/622/eaay6318. [DOI: 10.1126/scisignal.aay6318] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Apoptosis signal–regulating kinases (ASK1, ASK2, and ASK3) are activators of the p38 and c-Jun N-terminal kinase (JNK) mitogen-activated protein kinase (MAPK) pathways. ASK1–3 form oligomeric complexes known as ASK signalosomes that initiate signaling cascades in response to diverse stress stimuli. Here, we demonstrated that oligomerization of ASK proteins is driven by previously uncharacterized sterile-alpha motif (SAM) domains that reside at the carboxy-terminus of each ASK protein. SAM domains from ASK1–3 exhibited distinct behaviors, with the SAM domain of ASK1 forming unstable oligomers, that of ASK2 remaining predominantly monomeric, and that of ASK3 forming a stable oligomer even at a low concentration. In contrast to their behavior in isolation, the ASK1 and ASK2 SAM domains preferentially formed a stable heterocomplex. The crystal structure of the ASK3 SAM domain, small-angle x-ray scattering, and mutagenesis suggested that ASK3 oligomers and ASK1-ASK2 complexes formed discrete, quasi-helical rings through interactions between the mid-loop of one molecule and the end helix of another molecule. Preferential ASK1-ASK2 binding was consistent with mass spectrometry showing that full-length ASK1 formed hetero-oligomeric complexes incorporating large amounts of ASK2. Accordingly, disrupting the association between SAM domains impaired ASK activity in the context of electrophilic stress induced by 4-hydroxy-2-nonenal (HNE). These findings provide a structural template for how ASK proteins assemble foci that drive inflammatory signaling and reinforce the notion that strategies to target ASK proteins should consider the concerted actions of multiple ASK family members.
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Affiliation(s)
- Sarah J. Trevelyan
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, P.O. Box 56, 710 Cumberland St., Dunedin 9054, New Zealand
| | - Jodi L. Brewster
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, P.O. Box 56, 710 Cumberland St., Dunedin 9054, New Zealand
| | - Abigail E. Burgess
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, P.O. Box 56, 710 Cumberland St., Dunedin 9054, New Zealand
| | - Jennifer M. Crowther
- Biomolecular Interaction Centre, School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
| | - Antonia L. Cadell
- Kinghorn Cancer Centre, Garvan Institute of Medical Research, Sydney, New South Wales 2010, Australia
| | - Benjamin L. Parker
- Department of Physiology, School of Biomedical Sciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | - David R. Croucher
- Kinghorn Cancer Centre, Garvan Institute of Medical Research, Sydney, New South Wales 2010, Australia
- St Vincent’s Hospital Clinical School, University of New South Wales, Sydney, New South Wales, 2052, Australia
- School of Medicine and Medical Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - Renwick C. J. Dobson
- Biomolecular Interaction Centre, School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria 3010, Australia
| | - James M. Murphy
- Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Peter D. Mace
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, P.O. Box 56, 710 Cumberland St., Dunedin 9054, New Zealand
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16
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Rivoire O. Parsimonious evolutionary scenario for the origin of allostery and coevolution patterns in proteins. Phys Rev E 2020; 100:032411. [PMID: 31640027 DOI: 10.1103/physreve.100.032411] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Indexed: 12/16/2022]
Abstract
Proteins display generic properties that are challenging to explain by direct selection, notably allostery, the capacity to be regulated through long-range effects, and evolvability, the capacity to adapt to new selective pressures. An evolutionary scenario is proposed where proteins acquire these two features indirectly as a by-product of their selection for a more fundamental property, exquisite discrimination, the capacity to bind discriminatively very similar ligands. Achieving this task is shown to typically require proteins to undergo a conformational change. We argue that physical and evolutionary constraints impel this change to be controlled by a group of sites extending from the binding site. Proteins can thus acquire a latent potential for allosteric regulation and evolutionary adaptation because of long-range effects that initially arise as evolutionary spandrels. This scenario accounts for the groups of conserved and coevolving residues observed in multiple sequence alignments. However, we propose that most pairs of coevolving and contacting residues inferred from such alignments have a different origin, related to thermal stability. A physical model is presented that illustrates this evolutionary scenario and its implications. The scenario can be implemented in experiments of protein evolution to directly test its predictions.
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Affiliation(s)
- Olivier Rivoire
- Center for Interdisciplinary Research in Biology, Collège de France, Centre National de la Recherche Scientifique, INSERM, PSL Research University, 75005 Paris, France
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17
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Campitelli P, Modi T, Kumar S, Ozkan SB. The Role of Conformational Dynamics and Allostery in Modulating Protein Evolution. Annu Rev Biophys 2020; 49:267-288. [PMID: 32075411 DOI: 10.1146/annurev-biophys-052118-115517] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Advances in sequencing techniques and statistical methods have made it possible not only to predict sequences of ancestral proteins but also to identify thousands of mutations in the human exome, some of which are disease associated. These developments have motivated numerous theories and raised many questions regarding the fundamental principles behind protein evolution, which have been traditionally investigated horizontally using the tip of the phylogenetic tree through comparative studies of extant proteins within a family. In this article, we review a vertical comparison of the modern and resurrected ancestral proteins. We focus mainly on the dynamical properties responsible for a protein's ability to adapt new functions in response to environmental changes. Using the Dynamic Flexibility Index and the Dynamic Coupling Index to quantify the relative flexibility and dynamic coupling at a site-specific, single-amino-acid level, we provide evidence that the migration of hinges, which are often functionally critical rigid sites, is a mechanism through which proteins can rapidly evolve. Additionally, we show that disease-associated mutations in proteins often result in flexibility changes even at positions distal from mutational sites, particularly in the modulation of active site dynamics.
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Affiliation(s)
- Paul Campitelli
- Center for Biological Physics, Department of Physics, Arizona State University, Tempe, Arizona 85281, USA; , ,
| | - Tushar Modi
- Center for Biological Physics, Department of Physics, Arizona State University, Tempe, Arizona 85281, USA; , ,
| | - Sudhir Kumar
- Institute for Genomics and Evolutionary Medicine, Temple University, Philadelphia, Pennsylvania 19122, USA; .,Department of Biology, Temple University, Philadelphia, Pennsylvania 19122, USA.,Center for Excellence in Genome Medicine and Research, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - S Banu Ozkan
- Center for Biological Physics, Department of Physics, Arizona State University, Tempe, Arizona 85281, USA; , ,
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18
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McCormick JW, Pincus D, Resnekov O, Reynolds KA. Strategies for Engineering and Rewiring Kinase Regulation. Trends Biochem Sci 2019; 45:259-271. [PMID: 31866305 DOI: 10.1016/j.tibs.2019.11.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 11/13/2019] [Accepted: 11/15/2019] [Indexed: 12/31/2022]
Abstract
Eukaryotic protein kinases (EPKs) catalyze the transfer of a phosphate group onto another protein in response to appropriate regulatory cues. In doing so, they provide a primary means for cellular information transfer. Consequently, EPKs play crucial roles in cell differentiation and cell-cycle progression, and kinase dysregulation is associated with numerous disease phenotypes including cancer. Nonnative cues for synthetically regulating kinases are thus much sought after, both for dissecting cell signaling pathways and for pharmaceutical development. In recent years advances in protein engineering and sequence analysis have led to new approaches for manipulating kinase activity, localization, and in some instances specificity. These tools have revealed fundamental principles of intracellular signaling and suggest paths forward for the design of therapeutic allosteric kinase regulators.
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Affiliation(s)
- James W McCormick
- The Green Center for Systems Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - David Pincus
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA; Center for Physics of Evolving Systems, University of Chicago, Chicago, IL 60637, USA
| | | | - Kimberly A Reynolds
- The Green Center for Systems Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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19
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Negative Feedback Phosphorylation of Gγ Subunit Ste18 and the Ste5 Scaffold Synergistically Regulates MAPK Activation in Yeast. Cell Rep 2019; 23:1504-1515. [PMID: 29719261 PMCID: PMC5987779 DOI: 10.1016/j.celrep.2018.03.135] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 12/15/2017] [Accepted: 03/29/2018] [Indexed: 01/08/2023] Open
Abstract
Heterotrimeric G proteins (Gαβγ) are essential transducers in G protein signaling systems in all eukaryotes. In yeast, G protein signaling differentially activates mitogen-activated protein kinases (MAPKs)—Fus3 and Kss1—a phenomenon controlled by plasma membrane (PM) association of the scaffold protein Ste5. Here, we show that phosphorylation of the yeast Gγ subunit (Ste18), together with Fus3 docking on Ste5, controls the rate and stability of Ste5/PM association. Disruption of either element alone by point mutation has mild but reciprocal effects on MAPK activation. Disabling both elements results in ultra-fast and stable bulk Ste5/PM localization and Fus3 activation that is 6 times faster and 4 times more amplified compared to wild-type cells. These results further resolve the mechanism by which MAPK negative feedback phosphorylation controls pathway activation and provides compelling evidence that Gγ subunits can serve as intrinsic regulators of G protein signaling.
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20
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Coyote-Maestas W, He Y, Myers CL, Schmidt D. Domain insertion permissibility-guided engineering of allostery in ion channels. Nat Commun 2019; 10:290. [PMID: 30655517 PMCID: PMC6336875 DOI: 10.1038/s41467-018-08171-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 12/17/2018] [Indexed: 01/01/2023] Open
Abstract
Allostery is a fundamental principle of protein regulation that remains hard to engineer, particularly in membrane proteins such as ion channels. Here we use human Inward Rectifier K+ Channel Kir2.1 to map site-specific permissibility to the insertion of domains with different biophysical properties. We find that permissibility is best explained by dynamic protein properties, such as conformational flexibility. Several regions in Kir2.1 that are equivalent to those regulated in homologs, such as G-protein-gated inward rectifier K+ channels (GIRK), have differential permissibility; that is, for these sites permissibility depends on the structural properties of the inserted domain. Our data and the well-established link between protein dynamics and allostery led us to propose that differential permissibility is a metric of latent allosteric capacity in Kir2.1. In support of this notion, inserting light-switchable domains into sites with predicted latent allosteric capacity renders Kir2.1 activity sensitive to light. Allostery is a fundamental principle of protein regulation that remains challenging to engineer. Here authors screen human Inward Rectifier K + Channel Kir2.1 for permissibility to domain insertions and propose that differential permissibility is a metric of latent allosteric capacity in Kir2.1.
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Affiliation(s)
- Willow Coyote-Maestas
- Department of Biochemistry, Molecular Biology & Biophysics, University of Minnesota, Minneapolis, 55455, MN, USA
| | - Yungui He
- Department of Genetics, Cell Biology & Development, University of Minnesota, Minneapolis, 55455, MN, USA
| | - Chad L Myers
- Department of Computer Science and Engineering, University of Minnesota, Minneapolis, 55455, MN, USA
| | - Daniel Schmidt
- Department of Genetics, Cell Biology & Development, University of Minnesota, Minneapolis, 55455, MN, USA.
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21
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Understanding molecular mechanisms in cell signaling through natural and artificial sequence variation. Nat Struct Mol Biol 2018; 26:25-34. [PMID: 30598552 DOI: 10.1038/s41594-018-0175-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2018] [Accepted: 11/16/2018] [Indexed: 02/08/2023]
Abstract
The functionally tolerated sequence space of proteins can now be explored in an unprecedented way, owing to the expansion of genomic databases and the development of high-throughput methods to interrogate protein function. For signaling proteins, several recent studies have shown how the analysis of sequence variation leverages the available protein-structure information to provide new insights into specificity and allosteric regulation. In this Review, we discuss recent work that illustrates how this emerging approach is providing a deeper understanding of signaling proteins.
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22
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Phillips T, Tio CW, Omerza G, Rimal A, Lokareddy RK, Cingolani G, Winter E. RNA Recognition-like Motifs Activate a Mitogen-Activated Protein Kinase. Biochemistry 2018; 57:6878-6887. [PMID: 30452242 DOI: 10.1021/acs.biochem.8b01032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Smk1 is a mitogen-activated protein kinase (MAPK) family member in the yeast Saccharomyces cerevisiae that controls the postmeiotic program of spore formation. Ssp2 is a meiosis-specific protein that activates Smk1 and triggers the autophosphorylation of its activation loop. A fragment of Ssp2 that is sufficient to activate Smk1 contains two segments that resemble RNA recognition motifs (RRMs). Mutations in either of these motifs eliminated Ssp2's ability to activate Smk1. In contrast, deletions and insertions within the segment linking the RRM-like motifs only partially reduced the activity of Ssp2. Moreover, when the two RRM-like motifs were expressed as separate proteins in bacteria, they activated Smk1. We also find that both motifs can be cross-linked to Smk1 and that at least one of the motifs binds near the ATP-binding pocket of the MAPK. These findings demonstrate that motifs related to RRMs can directly activate protein kinases.
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Affiliation(s)
- Timothy Phillips
- Department of Biochemistry and Molecular Biology , Thomas Jefferson University , Philadelphia , Pennsylvania 19107 , United States
| | - Chong Wai Tio
- Department of Biochemistry and Molecular Biology , Thomas Jefferson University , Philadelphia , Pennsylvania 19107 , United States
| | - Gregory Omerza
- Department of Biochemistry and Molecular Biology , Thomas Jefferson University , Philadelphia , Pennsylvania 19107 , United States
| | - Abhimannyu Rimal
- Department of Biochemistry and Molecular Biology , Thomas Jefferson University , Philadelphia , Pennsylvania 19107 , United States
| | - Ravi K Lokareddy
- Department of Biochemistry and Molecular Biology , Thomas Jefferson University , Philadelphia , Pennsylvania 19107 , United States
| | - Gino Cingolani
- Department of Biochemistry and Molecular Biology , Thomas Jefferson University , Philadelphia , Pennsylvania 19107 , United States
| | - Edward Winter
- Department of Biochemistry and Molecular Biology , Thomas Jefferson University , Philadelphia , Pennsylvania 19107 , United States
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23
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Pincus D, Pandey JP, Feder ZA, Creixell P, Resnekov O, Reynolds KA. Engineering allosteric regulation in protein kinases. Sci Signal 2018; 11:11/555/eaar3250. [PMID: 30401787 DOI: 10.1126/scisignal.aar3250] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Phosphoregulation, in which the addition of a negatively charged phosphate group modulates protein activity, enables dynamic cellular responses. To understand how new phosphoregulation might be acquired, we mutationally scanned the surface of a prototypical yeast kinase (Kss1) to identify potential regulatory sites. The data revealed a set of spatially distributed "hotspots" that might have coevolved with the active site and preferentially modulated kinase activity. By engineering simple consensus phosphorylation sites at these hotspots, we rewired cell signaling in yeast. Using the same approach with a homolog yeast mitogen-activated protein kinase, Hog1, we introduced new phosphoregulation that modified its localization and signaling dynamics. Beyond revealing potential use in synthetic biology, our findings suggest that the identified hotspots contribute to the diversity of natural allosteric regulatory mechanisms in the eukaryotic kinome and, given that some are mutated in cancers, understanding these hotspots may have clinical relevance to human disease.
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Affiliation(s)
- David Pincus
- Whitehead Institute for Biomedical Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.
| | - Jai P Pandey
- Whitehead Institute for Biomedical Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Zoë A Feder
- Whitehead Institute for Biomedical Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Pau Creixell
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | | | - Kimberly A Reynolds
- Green Center for Systems Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA. .,Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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24
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Creixell P, Pandey JP, Palmeri A, Bhattacharyya M, Creixell M, Ranganathan R, Pincus D, Yaffe MB. Hierarchical Organization Endows the Kinase Domain with Regulatory Plasticity. Cell Syst 2018; 7:371-383.e4. [PMID: 30243563 DOI: 10.1016/j.cels.2018.08.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 06/24/2018] [Accepted: 08/13/2018] [Indexed: 02/08/2023]
Abstract
The functional diversity of kinases enables specificity in cellular signal transduction. Yet how more than 500 members of the human kinome specifically receive regulatory inputs and convey information to appropriate substrates-all while using the common signaling output of phosphorylation-remains enigmatic. Here, we perform statistical co-evolution analysis, mutational scanning, and quantitative live-cell assays to reveal a hierarchical organization of the kinase domain that facilitates the orthogonal evolution of regulatory inputs and substrate outputs while maintaining catalytic function. We find that three quasi-independent "sectors"-groups of evolutionarily coupled residues-represent functional units in the kinase domain that encode for catalytic activity, substrate specificity, and regulation. Sector positions impact both disease and pharmacology: the catalytic sector is significantly enriched for somatic cancer mutations, and residues in the regulatory sector interact with allosteric kinase inhibitors. We propose that this functional architecture endows the kinase domain with inherent regulatory plasticity.
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Affiliation(s)
- Pau Creixell
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Departments of Biology and Bioengineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Jai P Pandey
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | | | - Moitrayee Bhattacharyya
- Department of Molecular and Cell Biology and California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Marc Creixell
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Departments of Biology and Bioengineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Rama Ranganathan
- Center for Physics of Evolving Systems, Department of Biochemistry and Molecular Biology, Institute for Molecular Engineering, University of Chicago, Chicago, IL 60637, USA
| | - David Pincus
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA.
| | - Michael B Yaffe
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Departments of Biology and Bioengineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Surgery, Beth Israel Deaconess Medical Center, Divisions of Acute Care Surgery, Trauma, and Critical Care and Surgical Oncology, Harvard Medical School, Boston 02215, USA.
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25
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Aluru M, McKinney T, Venero AKL, Choudhury S, Torres M. Mitogen-activated protein kinases, Fus3 and Kss1, regulate chronological lifespan in yeast. Aging (Albany NY) 2017; 9:2587-2609. [PMID: 29273704 PMCID: PMC5764394 DOI: 10.18632/aging.101350] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 12/11/2017] [Indexed: 04/19/2023]
Abstract
Using a systems-based approach, we have identified several genes not previously evaluated for a role(s) in chronological aging. Here, we have thoroughly investigated the chronological lifespan (CLS) of three of these genes (FUS3, KSS1 and HOG1) and their protein products, each of which have well-defined cell signaling roles in young cells. The importance of FUS3 and KSS1 in CLS are largely unknown and analyzed here for the first time. Using both qualitative and quantitative CLS assays, we show that deletion of any of the three MAPK's increases yeast lifespan. Furthermore, combined deletion of any MAPK and TOR1, most prominently fus3Δ/tor1Δ, produces a two-stage CLS response ending in lifespan increase greater than that of tor1Δ. Similar effects are achieved upon endogenous expression of a non-activatable form of Fus3. We speculate that the autophagy-promoting role of FUS3, which is inherently antagonistic to the role of TOR1, may in part be responsible for the differential aging phenotype of fus3Δ/tor1Δ. Consistent with this notion we show that nitrogen starvation, which promotes autophagy by deactivating Tor1, results in decreased CLS if FUS3 is deleted. Taken together, these results reveal a previously unrealized effect of mating-specific MAPKs in the chronological lifespan of yeast.
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Affiliation(s)
- Maneesha Aluru
- Georgia Institute of Technology, School of Biological Sciences, Atlanta, GA 30332, USA
| | - Tori McKinney
- Georgia Institute of Technology, School of Biological Sciences, Atlanta, GA 30332, USA
| | | | - Shilpa Choudhury
- Georgia Institute of Technology, School of Biological Sciences, Atlanta, GA 30332, USA
| | - Matthew Torres
- Georgia Institute of Technology, School of Biological Sciences, Atlanta, GA 30332, USA
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26
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Epigenetic control of pheromone MAPK signaling determines sexual fecundity in Candida albicans. Proc Natl Acad Sci U S A 2017; 114:13780-13785. [PMID: 29255038 DOI: 10.1073/pnas.1711141115] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Several pathogenic Candida species are capable of heritable and reversible switching between two epigenetic states, "white" and "opaque." In Candida albicans, white cells are essentially sterile, whereas opaque cells are mating-proficient. Here, we interrogate the mechanism by which the white-opaque switch regulates sexual fecundity and identify four genes in the pheromone MAPK pathway that are expressed at significantly higher levels in opaque cells than in white cells. These genes encode the β subunit of the G-protein complex (STE4), the pheromone MAPK scaffold (CST5), and the two terminal MAP kinases (CEK1/CEK2). To define the contribution of each factor to mating, C. albicans white cells were reverse-engineered to express elevated, opaque-like levels of these factors, either singly or in combination. We show that white cells co-overexpressing STE4, CST5, and CEK2 undergo mating four orders of magnitude more efficiently than control white cells and at a frequency approaching that of opaque cells. Moreover, engineered white cells recapitulate the transcriptional and morphological responses of opaque cells to pheromone. These results therefore reveal multiple bottlenecks in pheromone MAPK signaling in white cells and that alleviation of these bottlenecks enables efficient mating by these "sterile" cell types. Taken together, our findings establish that differential expression of several MAPK factors underlies the epigenetic control of mating in C. albicans We also discuss how fitness advantages could have driven the evolution of a toggle switch to regulate sexual reproduction in pathogenic Candida species.
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27
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Gardner NW, McGinness SM, Panchal J, Topp EM, Park C. A Cooperative Folding Unit as the Structural Link for Energetic Coupling within a Protein. Biochemistry 2017; 56:6555-6564. [PMID: 29166011 DOI: 10.1021/acs.biochem.7b00850] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Previously, we demonstrated that binding of a ligand to Escherichia coli cofactor-dependent phosphoglycerate mutase (dPGM), a homodimeric protein, is energetically coupled with dimerization. The equilibrium unfolding of dPGM occurs with a stable, monomeric intermediate. Binding of several nonsubstrate metabolites stabilizes the dimeric native form over the monomeric intermediate, reducing the population of the intermediate. Both the active site and the dimer interface appear to be unfolded in the intermediate. We hypothesized that a loop containing residues 118-152 was responsible for the energetic coupling between the dimer interface and the distal active site and was unfolded in the intermediate. Here, we investigated the structure of the dPGM intermediate by probing side-chain interactions and solvent accessibility of the peptide backbone. By comparing the effect of a mutation on the global stability and the stability of the intermediate, we determine an equilibrium φ value (φeq value), which provides information about whether side-chain interactions are retained or lost in the intermediate. Hydrogen/deuterium exchange coupled with mass spectrometry (HDX-MS) was used to investigate differences in the solvent accessibility of the peptide backbone in the intermediate and native forms of dPGM. The results of φeq value analysis and HDX-MS reveal the least stable folding unit of dPGM, which is unfolded in the intermediate and links the active site to the dimer interface. The structure of the intermediate reveals how the cooperative network of residues in dPGM gives rise to the observed energetic coupling between dimerization and ligand binding.
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Affiliation(s)
- Nathan W Gardner
- Department of Medicinal Chemistry and Molecular Pharmacology, ‡Interdisciplinary Life Science Graduate Program, §Department of Industrial and Physical Pharmacy, and ∥Bindley Bioscience Center, Purdue University , West Lafayette, Indiana 47907, United States
| | - Sarah M McGinness
- Department of Medicinal Chemistry and Molecular Pharmacology, ‡Interdisciplinary Life Science Graduate Program, §Department of Industrial and Physical Pharmacy, and ∥Bindley Bioscience Center, Purdue University , West Lafayette, Indiana 47907, United States
| | - Jainik Panchal
- Department of Medicinal Chemistry and Molecular Pharmacology, ‡Interdisciplinary Life Science Graduate Program, §Department of Industrial and Physical Pharmacy, and ∥Bindley Bioscience Center, Purdue University , West Lafayette, Indiana 47907, United States
| | - Elizabeth M Topp
- Department of Medicinal Chemistry and Molecular Pharmacology, ‡Interdisciplinary Life Science Graduate Program, §Department of Industrial and Physical Pharmacy, and ∥Bindley Bioscience Center, Purdue University , West Lafayette, Indiana 47907, United States
| | - Chiwook Park
- Department of Medicinal Chemistry and Molecular Pharmacology, ‡Interdisciplinary Life Science Graduate Program, §Department of Industrial and Physical Pharmacy, and ∥Bindley Bioscience Center, Purdue University , West Lafayette, Indiana 47907, United States
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Ssp2 Binding Activates the Smk1 Mitogen-Activated Protein Kinase. Mol Cell Biol 2017; 37:MCB.00607-16. [PMID: 28223369 DOI: 10.1128/mcb.00607-16] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 02/10/2017] [Indexed: 01/20/2023] Open
Abstract
Smk1 is a meiosis-specific mitogen-activated protein kinase (MAPK) in Saccharomyces cerevisiae that couples spore morphogenesis to the completion of chromosome segregation. Similar to other MAPKs, Smk1 is controlled by phosphorylation of a threonine (T) and a tyrosine (Y) in its activation loop. However, it is not activated by a dual-specificity MAPK kinase. Instead, T207 in Smk1's activation loop is phosphorylated by the cyclin-dependent kinase (CDK)-activating kinase (Cak1), and Y209 is autophosphorylated in an intramolecular reaction that requires the meiosis-specific protein Ssp2. In this study, we show that Smk1 is catalytically inert unless it is bound by Ssp2. While Ssp2 binding activates Smk1 by a mechanism that is independent of activation loop phosphorylation, binding also triggers autophosphorylation of Y209 in Smk1, which, along with Cak1-mediated phosphorylation of T207, further activates the kinase. Autophosphorylation of Smk1 on Y209 also appears to modify the specificity of the MAPK by suppressing Y kinase and enhancing S/T kinase activity. We also found that the phosphoconsensus motif preference of Ssp2/Smk1 is more extensive than that of other characterized MAPKs. This study therefore defines a novel mechanism of MAPK activation requiring binding of an activator and also shows that MAPKs can be diversified to recognize unique phosphorylation motifs.
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Pincus D, Resnekov O, Reynolds KA. An evolution-based strategy for engineering allosteric regulation. Phys Biol 2017; 14:025002. [PMID: 28266924 DOI: 10.1088/1478-3975/aa64a4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Allosteric regulation provides a way to control protein activity at the time scale of milliseconds to seconds inside the cell. An ability to engineer synthetic allosteric systems would be of practical utility for the development of novel biosensors, creation of synthetic cell signaling pathways, and design of small molecule pharmaceuticals with regulatory impact. To this end, we outline a general approach-termed rational engineering of allostery at conserved hotspots (REACH)-to introduce novel regulation into a protein of interest by exploiting latent allostery that has been hard-wired by evolution into its structure. REACH entails the use of statistical coupling analysis (SCA) to identify 'allosteric hotspots' on protein surfaces, the development and implementation of experimental assays to test hotspots for functionality, and a toolkit of allosteric modulators to impinge on endogenous cellular circuitry. REACH can be broadly applied to rewire cellular processes to respond to novel inputs.
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Affiliation(s)
- David Pincus
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, United States of America. All authors contributed equally and are listed alphabetically
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30
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Nocedal I, Mancera E, Johnson AD. Gene regulatory network plasticity predates a switch in function of a conserved transcription regulator. eLife 2017; 6:e23250. [PMID: 28327289 PMCID: PMC5391208 DOI: 10.7554/elife.23250] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2016] [Accepted: 03/21/2017] [Indexed: 12/15/2022] Open
Abstract
The rewiring of gene regulatory networks can generate phenotypic novelty. It remains an open question, however, how the large number of connections needed to form a novel network arise over evolutionary time. Here, we address this question using the network controlled by the fungal transcription regulator Ndt80. This conserved protein has undergone a dramatic switch in function-from an ancestral role regulating sporulation to a derived role regulating biofilm formation. This switch in function corresponded to a large-scale rewiring of the genes regulated by Ndt80. However, we demonstrate that the Ndt80-target gene connections were undergoing extensive rewiring prior to the switch in Ndt80's regulatory function. We propose that extensive drift in the Ndt80 regulon allowed for the exploration of alternative network structures without a loss of ancestral function, thereby facilitating the formation of a network with a new function.
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Affiliation(s)
- Isabel Nocedal
- Department of Microbiology and Immunology, University of California, San Francisco, United States
- Department of Biochemistry and Biophysics, University of California, San Francisco, United States
| | - Eugenio Mancera
- Department of Microbiology and Immunology, University of California, San Francisco, United States
- Department of Biochemistry and Biophysics, University of California, San Francisco, United States
| | - Alexander D Johnson
- Department of Microbiology and Immunology, University of California, San Francisco, United States
- Department of Biochemistry and Biophysics, University of California, San Francisco, United States
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Xing L, An Y, Shi G, Yan J, Xie P, Qu Z, Zhang Z, Liu Z, Pan D, Xu Y. Correlated evolution between CK1δ Protein and the Serine-rich Motif Contributes to Regulating the Mammalian Circadian Clock. J Biol Chem 2016; 292:161-171. [PMID: 27879317 DOI: 10.1074/jbc.m116.751214] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 11/21/2016] [Indexed: 11/06/2022] Open
Abstract
Understanding the mechanism underlying the physiological divergence of species is a long-standing issue in evolutionary biology. The circadian clock is a highly conserved system existing in almost all organisms that regulates a wide range of physiological and behavioral events to adapt to the day-night cycle. Here, the interactions between hCK1ϵ/δ/DBT (Drosophila ortholog of CK1δ/ϵ) and serine-rich (SR) motifs from hPER2 (ortholog of Drosophila per) were reconstructed in a Drosophila circadian system. The results indicated that in Drosophila, the SR mutant form hPER2S662G does not recapitulate the mouse or human mutant phenotype. However, introducing hCK1δ (but not DBT) shortened the circadian period and restored the SR motif function. We found that hCK1δ is catalytically more efficient than DBT in phosphorylating the SR motif, which demonstrates that the evolution of CK1δ activity is required for SR motif modulation. Moreover, an abundance of phosphorylatable SR motifs and the striking emergence of putative SR motifs in vertebrate proteins were observed, which provides further evidence that the correlated evolution between kinase activity and its substrates set the stage for functional diversity in vertebrates. It is possible that such correlated evolution may serve as a biomarker associated with the adaptive benefits of diverse organisms. These results also provide a concrete example of how functional synthesis can be achieved through introducing evolutionary partners in vivo.
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Affiliation(s)
- Lijuan Xing
- From the Cambridge-Suda Genomic Resource Center, Soochow University, 199 Renai Road, Suzhou 215123 and
| | - Yang An
- the MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University, 12 Xuefu Road, Pukou District, Nanjing 210061, China
| | - Guangsen Shi
- From the Cambridge-Suda Genomic Resource Center, Soochow University, 199 Renai Road, Suzhou 215123 and
| | - Jie Yan
- From the Cambridge-Suda Genomic Resource Center, Soochow University, 199 Renai Road, Suzhou 215123 and
| | - Pancheng Xie
- the MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University, 12 Xuefu Road, Pukou District, Nanjing 210061, China
| | - Zhipeng Qu
- the MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University, 12 Xuefu Road, Pukou District, Nanjing 210061, China
| | - Zhihui Zhang
- the MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University, 12 Xuefu Road, Pukou District, Nanjing 210061, China
| | - Zhiwei Liu
- From the Cambridge-Suda Genomic Resource Center, Soochow University, 199 Renai Road, Suzhou 215123 and
| | - Dejing Pan
- From the Cambridge-Suda Genomic Resource Center, Soochow University, 199 Renai Road, Suzhou 215123 and
| | - Ying Xu
- From the Cambridge-Suda Genomic Resource Center, Soochow University, 199 Renai Road, Suzhou 215123 and .,the MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University, 12 Xuefu Road, Pukou District, Nanjing 210061, China
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Beenstock J, Mooshayef N, Engelberg D. How Do Protein Kinases Take a Selfie (Autophosphorylate)? Trends Biochem Sci 2016; 41:938-953. [DOI: 10.1016/j.tibs.2016.08.006] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2016] [Revised: 07/13/2016] [Accepted: 08/02/2016] [Indexed: 12/18/2022]
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Saxton RA, Chantranupong L, Knockenhauer KE, Schwartz TU, Sabatini DM. Mechanism of arginine sensing by CASTOR1 upstream of mTORC1. Nature 2016; 536:229-33. [PMID: 27487210 PMCID: PMC4988899 DOI: 10.1038/nature19079] [Citation(s) in RCA: 206] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 07/05/2016] [Indexed: 12/25/2022]
Abstract
The mechanistic Target of Rapamycin Complex 1 (mTORC1) is a major regulator of eukaryotic growth that coordinates anabolic and catabolic cellular processes with inputs such as growth factors and nutrients, including amino acids. In mammals arginine is particularly important, promoting diverse physiological effects such as immune cell activation, insulin secretion, and muscle growth, largely mediated through activation of mTORC1 (refs 4, 5, 6, 7). Arginine activates mTORC1 upstream of the Rag family of GTPases, through either the lysosomal amino acid transporter SLC38A9 or the GATOR2-interacting Cellular Arginine Sensor for mTORC1 (CASTOR1). However, the mechanism by which the mTORC1 pathway detects and transmits this arginine signal has been elusive. Here, we present the 1.8 Å crystal structure of arginine-bound CASTOR1. Homodimeric CASTOR1 binds arginine at the interface of two Aspartate kinase, Chorismate mutase, TyrA (ACT) domains, enabling allosteric control of the adjacent GATOR2-binding site to trigger dissociation from GATOR2 and downstream activation of mTORC1. Our data reveal that CASTOR1 shares substantial structural homology with the lysine-binding regulatory domain of prokaryotic aspartate kinases, suggesting that the mTORC1 pathway exploited an ancient, amino-acid-dependent allosteric mechanism to acquire arginine sensitivity. Together, these results establish a structural basis for arginine sensing by the mTORC1 pathway and provide insights into the evolution of a mammalian nutrient sensor.
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Affiliation(s)
- Robert A. Saxton
- Department of Biology, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA
- Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA
- Howard Hughes Medical Institute, Cambridge, MA 02139, USA
- Koch Institute for Integrative Cancer Research, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
- Broad Institute of Harvard and Massachusetts Institute of Technology, 415 Main Street, Cambridge MA 02142, USA
| | - Lynne Chantranupong
- Department of Biology, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA
- Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA
- Howard Hughes Medical Institute, Cambridge, MA 02139, USA
- Koch Institute for Integrative Cancer Research, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
- Broad Institute of Harvard and Massachusetts Institute of Technology, 415 Main Street, Cambridge MA 02142, USA
| | - Kevin E. Knockenhauer
- Department of Biology, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA
| | - Thomas U. Schwartz
- Department of Biology, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA
| | - David M. Sabatini
- Department of Biology, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA
- Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA
- Howard Hughes Medical Institute, Cambridge, MA 02139, USA
- Koch Institute for Integrative Cancer Research, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
- Broad Institute of Harvard and Massachusetts Institute of Technology, 415 Main Street, Cambridge MA 02142, USA
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Yanagida H, Gispan A, Kadouri N, Rozen S, Sharon M, Barkai N, Tawfik DS. The Evolutionary Potential of Phenotypic Mutations. PLoS Genet 2015; 11:e1005445. [PMID: 26244544 PMCID: PMC4526572 DOI: 10.1371/journal.pgen.1005445] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 07/15/2015] [Indexed: 01/08/2023] Open
Abstract
Errors in protein synthesis, so-called phenotypic mutations, are orders-of-magnitude more frequent than genetic mutations. Here, we provide direct evidence that alternative protein forms and phenotypic variability derived from translational errors paved the path to genetic, evolutionary adaptations via gene duplication. We explored the evolutionary origins of Saccharomyces cerevisiae IDP3 - an NADP-dependent isocitrate dehydrogenase mediating fatty acids ß-oxidation in the peroxisome. Following the yeast whole genome duplication, IDP3 diverged from a cytosolic ancestral gene by acquisition of a C-terminal peroxisomal targeting signal. We discovered that the pre-duplicated cytosolic IDPs are partially localized to the peroxisome owing to +1 translational frameshifts that bypass the stop codon and unveil cryptic peroxisomal targeting signals within the 3’-UTR. Exploring putative cryptic signals in all 3’-UTRs of yeast genomes, we found that other enzymes related to NADPH production such as pyruvate carboxylase 1 (PYC1) might be prone to peroxisomal localization via cryptic signals. Using laboratory evolution we found that these translational frameshifts are rapidly imprinted via genetic single base deletions occurring within the very same gene location. Further, as exemplified here, the sequences that promote translational frameshifts are also more prone to genetic deletions. Thus, genotypes conferring higher phenotypic variability not only meet immediate challenges by unveiling cryptic 3’-UTR sequences, but also boost the potential for future genetic adaptations. The rarity of genetic mutations limits the likelihood of adaptation. However, transcriptional and translational errors, so-called phenotypic mutations, are >105-fold more frequent, thus generating protein mutants from unmodified genes. We provide the first evidence that phenotypic mutations paved the path to what later, after gene duplication, became newly compartmentalized enzymes. Thus, gene duplication followed rather than initiated the divergence of this new trait. Our findings also show that translational infidelity and phenotypic variability comprise the origins of evolutionary innovations, and how selection for enhanced phenotypic variability also promotes the appearance of genetic mutations that lead to the very same outcome.
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Affiliation(s)
- Hayato Yanagida
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot, Israel
| | - Ariel Gispan
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Noam Kadouri
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Shelly Rozen
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot, Israel
| | - Michal Sharon
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot, Israel
| | - Naama Barkai
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Dan S. Tawfik
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot, Israel
- * E-mail:
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Ryu J, Park SH. Simple synthetic protein scaffolds can create adjustable artificial MAPK circuits in yeast and mammalian cells. Sci Signal 2015; 8:ra66. [PMID: 26126717 DOI: 10.1126/scisignal.aab3397] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
As hubs for eukaryotic cell signaling, scaffold proteins are attractive targets for engineering and manipulating signaling circuits. We designed synthetic scaffolds with a repeated PDZ domain that interacted with engineered kinases of the mitogen-activated protein kinase (MAPK) cascade involved in yeast mating to investigate how modular interactions mediate kinase cascades. The synthetic scaffolds functioned as logic gates of signaling circuits. We replaced the endogenous yeast scaffold Ste5 with designer scaffolds with a variable numbers of a PDZ domain that bound kinases or phosphatases engineered with a PDZ-binding motif. Although association with the membrane was necessary for pathway activity, surprisingly, mating responses occurred when the circuit contained a scaffold with only two PDZ domains, which could only bind two of the three kinases simultaneously. Additionally, the three tiers of the MAPK pathway exhibited decreasing positional plasticity from the top [MAPK kinase kinase (MAPKKK)] to the bottom (MAPK) tier such that binding of a MAPKKK, but not a MAPK, from the osmoregulatory pathway or protein kinase C pathway to the synthetic scaffold activated a reporter of the mating response. We also showed that the output duration and intensity could be altered by recruiting phosphatases or varying the affinity of the recruited proteins for the scaffold and that a designer MAPK scaffold functioned in mammalian cells. Thus, this synthetic approach with designer scaffolds should enable the rational manipulation or engineering of signaling pathways and provide insight into the functional roles of scaffold proteins.
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Affiliation(s)
- Jihoon Ryu
- Department of Biological Sciences, Seoul National University, Seoul 151-742, Korea
| | - Sang-Hyun Park
- Department of Biological Sciences, Seoul National University, Seoul 151-742, Korea.
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36
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Anderson DW, McKeown AN, Thornton JW. Intermolecular epistasis shaped the function and evolution of an ancient transcription factor and its DNA binding sites. eLife 2015; 4:e07864. [PMID: 26076233 PMCID: PMC4500092 DOI: 10.7554/elife.07864] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 06/13/2015] [Indexed: 02/07/2023] Open
Abstract
Complexes of specifically interacting molecules, such as transcription factor proteins (TFs) and the DNA response elements (REs) they recognize, control most biological processes, but little is known concerning the functional and evolutionary effects of epistatic interactions across molecular interfaces. We experimentally characterized all combinations of genotypes in the joint protein-DNA sequence space defined by an historical transition in TF-RE specificity that occurred some 500 million years ago in the DNA-binding domain of an ancient steroid hormone receptor. We found that rampant epistasis within and between the two molecules was essential to specific TF-RE recognition and to the evolution of a novel TF-RE complex with unique derived specificity. Permissive and restrictive epistatic mutations across the TF-RE interface opened and closed potential evolutionary paths accessible by the other, making the evolution of each molecule contingent on its partner's history and allowing a molecular complex with novel specificity to evolve.
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Affiliation(s)
- Dave W Anderson
- Institute of Ecology and Evolution, University of Oregon, Eugene, United States
| | - Alesia N McKeown
- Institute of Ecology and Evolution, University of Oregon, Eugene, United States
| | - Joseph W Thornton
- Department of Ecology and Evolution, University of Chicago, Chicago, United States
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37
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Sikosek T, Chan HS. Biophysics of protein evolution and evolutionary protein biophysics. J R Soc Interface 2015; 11:20140419. [PMID: 25165599 DOI: 10.1098/rsif.2014.0419] [Citation(s) in RCA: 150] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The study of molecular evolution at the level of protein-coding genes often entails comparing large datasets of sequences to infer their evolutionary relationships. Despite the importance of a protein's structure and conformational dynamics to its function and thus its fitness, common phylogenetic methods embody minimal biophysical knowledge of proteins. To underscore the biophysical constraints on natural selection, we survey effects of protein mutations, highlighting the physical basis for marginal stability of natural globular proteins and how requirement for kinetic stability and avoidance of misfolding and misinteractions might have affected protein evolution. The biophysical underpinnings of these effects have been addressed by models with an explicit coarse-grained spatial representation of the polypeptide chain. Sequence-structure mappings based on such models are powerful conceptual tools that rationalize mutational robustness, evolvability, epistasis, promiscuous function performed by 'hidden' conformational states, resolution of adaptive conflicts and conformational switches in the evolution from one protein fold to another. Recently, protein biophysics has been applied to derive more accurate evolutionary accounts of sequence data. Methods have also been developed to exploit sequence-based evolutionary information to predict biophysical behaviours of proteins. The success of these approaches demonstrates a deep synergy between the fields of protein biophysics and protein evolution.
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Affiliation(s)
- Tobias Sikosek
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada M5S 1A8 Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada M5S 1A8 Department of Physics, University of Toronto, Toronto, Ontario, Canada M5S 1A8
| | - Hue Sun Chan
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada M5S 1A8 Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada M5S 1A8 Department of Physics, University of Toronto, Toronto, Ontario, Canada M5S 1A8
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38
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HAM-5 functions as a MAP kinase scaffold during cell fusion in Neurospora crassa. PLoS Genet 2014; 10:e1004783. [PMID: 25412208 PMCID: PMC4238974 DOI: 10.1371/journal.pgen.1004783] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 09/26/2014] [Indexed: 11/19/2022] Open
Abstract
Cell fusion in genetically identical Neurospora crassa germlings and in hyphae is a highly regulated process involving the activation of a conserved MAP kinase cascade that includes NRC-1, MEK-2 and MAK-2. During chemotrophic growth in germlings, the MAP kinase cascade members localize to conidial anastomosis tube (CAT) tips every ∼8 minutes, perfectly out of phase with another protein that is recruited to the tip: SOFT, a recently identified scaffold for the MAK-1 MAP kinase pathway in Sordaria macrospora. How the MAK-2 oscillation process is initiated, maintained and what proteins regulate the MAP kinase cascade is currently unclear. A global phosphoproteomics approach using an allele of mak-2 (mak-2Q100G) that can be specifically inhibited by the ATP analog 1NM-PP1 was utilized to identify MAK-2 kinase targets in germlings that were potentially involved in this process. One such putative target was HAM-5, a protein of unknown biochemical function. Previously, Δham-5 mutants were shown to be deficient for hyphal fusion. Here we show that HAM-5-GFP co-localized with NRC-1, MEK-2 and MAK-2 and oscillated with identical dynamics from the cytoplasm to CAT tips during chemotropic interactions. In the Δmak-2 strain, HAM-5-GFP localized to punctate complexes that did not oscillate, but still localized to the germling tip, suggesting that MAK-2 activity influences HAM-5 function/localization. However, MAK-2-GFP showed cytoplasmic and nuclear localization in a Δham-5 strain and did not localize to puncta. Via co-immunoprecipitation experiments, HAM-5 was shown to physically interact with NRC-1, MEK-2 and MAK-2, suggesting that it functions as a scaffold/transport hub for the MAP kinase cascade members for oscillation and chemotropic interactions during germling and hyphal fusion in N. crassa. The identification of HAM-5 as a scaffold-like protein will help to link the activation of MAK-2 cascade to upstream factors and proteins involved in this intriguing process of fungal communication. Cell fusion between genetically identical cells of the fungus Neurospora crassa occurs when germinating asexual cells (conidia) sense each other's proximity and redirect their growth. Chemotropic growth is dependent upon the assembly of a MAPK cascade (NRC-1/MEK-2/MAK-2) at the cell cortex (conidial anastomosis tubes; CATs), followed by disassembly over an ∼8 min cycle. A second protein required for fusion, SO, also assembles and disassembles at CAT tips during chemotropic growth, but with perfectly opposite dynamics to the MAK-2 complex. This process of germling chemotropism, oscillation and cell fusion is regulated by many genes and is poorly understood. Via a phosphoproteomics approach, we identify HAM-5, which functions as a scaffold for the MAK-2 signal transduction complex. HAM-5 is required for assembly/disassembly and oscillation of the MAK-2 complex during chemotropic growth. Our data supports a model whereby regulated modification of HAM-5 controls the disassembly of the MAK-2 MAPK complex and is essential for modulating the tempo of oscillation during chemotropic interactions.
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Howard CJ, Hanson-Smith V, Kennedy KJ, Miller CJ, Lou HJ, Johnson AD, Turk BE, Holt LJ. Ancestral resurrection reveals evolutionary mechanisms of kinase plasticity. eLife 2014; 3:e04126. [PMID: 25310241 PMCID: PMC4228266 DOI: 10.7554/elife.04126] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Accepted: 10/09/2014] [Indexed: 01/02/2023] Open
Abstract
Protein kinases have evolved diverse specificities to enable cellular information processing. To gain insight into the mechanisms underlying kinase diversification, we studied the CMGC protein kinases using ancestral reconstruction. Within this group, the cyclin dependent kinases (CDKs) and mitogen activated protein kinases (MAPKs) require proline at the +1 position of their substrates, while Ime2 prefers arginine. The resurrected common ancestor of CDKs, MAPKs, and Ime2 could phosphorylate substrates with +1 proline or arginine, with preference for proline. This specificity changed to a strong preference for +1 arginine in the lineage leading to Ime2 via an intermediate with equal specificity for proline and arginine. Mutant analysis revealed that a variable residue within the kinase catalytic cleft, DFGx, modulates +1 specificity. Expansion of Ime2 kinase specificity by mutation of this residue did not cause dominant deleterious effects in vivo. Tolerance of cells to new specificities likely enabled the evolutionary divergence of kinases.
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Affiliation(s)
- Conor J Howard
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Victor Hanson-Smith
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, United States
| | - Kristopher J Kennedy
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Chad J Miller
- Department of Pharmacology, Yale University School of Medicine, New Haven, United States
| | - Hua Jane Lou
- Department of Pharmacology, Yale University School of Medicine, New Haven, United States
| | - Alexander D Johnson
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, United States
| | - Benjamin E Turk
- Department of Pharmacology, Yale University School of Medicine, New Haven, United States
| | - Liam J Holt
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
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Das Adhikari AK, Qureshi MT, Kar RK, Bhat PJ. Perturbation of the interaction between Gal4p and Gal80p of the Saccharomyces cerevisiae GAL switch results in altered responses to galactose and glucose. Mol Microbiol 2014; 94:202-17. [PMID: 25135592 DOI: 10.1111/mmi.12757] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/13/2014] [Indexed: 11/30/2022]
Abstract
In S. cerevisiae, following the Whole Genome Duplication (WGD), GAL1-encoded galactokinase retained its signal transduction function but lost basal expression. On the other hand, its paralogue GAL3, lost kinase activity but retained its signalling function and basal expression, thus making it indispensable for the rapid induction of the S. cerevisiae GAL switch. However, a gal3Δ strain exhibits delayed growth kinetics due to the redundant signalling function of GAL1. The subfunctionalization between the paralogues GAL1 and GAL3 is due to expression divergence and is proposed to be due to the alteration in the Upstream Activating Sequences (UASG ). We demonstrate that the GAL switch becomes independent of GAL3 by altering the interaction between Gal4p and Gal80p without altering the configuration of UASG . In addition to the above, the altered switch of S. cerevisiae loses ultrasensitivity and stringent glucose repression. These changes caused an increase in fitness in the disaccharide melibiose at the expense of a decrease in fitness in galactose. The above altered features of the ScGAL switch are similar to the features of the GAL switch of K. lactis that diverged from S. cerevisiae before the WGD.
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Affiliation(s)
- Akshay Kumar Das Adhikari
- Laboratory of Molecular Genetics, Department of Bioscience and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
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Huang P, López Villar E. Possible mechanism and clinical potentials of allostery. Clin Transl Med 2014; 3:18. [PMID: 25024818 PMCID: PMC4091739 DOI: 10.1186/2001-1326-3-18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 06/16/2014] [Indexed: 11/10/2022] Open
Abstract
Allostery is involved in the dynamic regulation of biological functions in proteins. Advances in allostery research have recently drawn great interest and brought allostery closer to the clinic. The present commentary describes the mechanism by which allostery may involve in from a cell-wide view and its contribution to the discovery of new therapeutics to diseases.
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Affiliation(s)
- Peixin Huang
- Liver Cancer Institute, Pulmonary Department, Fudan University Zhongshan Hospital, Shanghai 200032, China
| | - Elena López Villar
- Department of Oncohematology of Children, Hospital Universitario Niño Jesús, Avda. Menéndez Pelayo, NO 65, 28009 Madrid, Spain
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Complex regulation of hydrolytic enzyme genes for cellulosic biomass degradation in filamentous fungi. Appl Microbiol Biotechnol 2014; 98:4829-37. [DOI: 10.1007/s00253-014-5707-6] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Revised: 03/17/2014] [Accepted: 03/17/2014] [Indexed: 12/17/2022]
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