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Ishida H, Kono H. Free Energy Landscape of H2A-H2B Displacement From Nucleosome. J Mol Biol 2022; 434:167707. [PMID: 35777463 DOI: 10.1016/j.jmb.2022.167707] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 06/11/2022] [Accepted: 06/23/2022] [Indexed: 12/14/2022]
Abstract
Nucleosome reconstitution plays an important role in many cellular functions. As an initial step, H2A-H2B dimer displacement, which is accompanied by disruption of many of the interactions within the nucleosome, should occur. To understand how H2A-H2B dimer displacement occurs, an adaptively biased molecular dynamics (ABMD) simulation was carried out to generate a variety of displacements of the H2A-H2B dimer from the fully wrapped to partially unwrapped nucleosome structures. With regards to these structures, the free energy landscape of the dimer displacement was investigated using umbrella sampling simulations. We found that the main contributors to the free energy were the docking domain of H2A and the C-terminal of H4. There were various paths for the dimer displacement which were dependent on the extent of nucleosomal DNA wrapping, suggesting that modulation of the intra-nucleosomal interaction by external factors such as histone chaperons could control the path for the H2A-H2B dimer displacement. Key residues which contributed to the free energy have also been reported to be involved in the mutations and posttranslational modifications (PTMs) which are important for assembling and/or reassembling the nucleosome at the molecular level and are found in cancer cells at the phenotypic level. Our results give insight into how the H2A-H2B dimer displacement proceeds along various paths according to different interactions within the nucleosome.
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Affiliation(s)
- Hisashi Ishida
- Institute for Quantum Life Science, National Institutes for Quantum Science and Technology, 619-0215 Kizugawa, Kyoto, Japan.
| | - Hidetoshi Kono
- Institute for Quantum Life Science, National Institutes for Quantum Science and Technology, 619-0215 Kizugawa, Kyoto, Japan
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2
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Torsional stress can regulate the unwrapping of two outer half superhelical turns of nucleosomal DNA. Proc Natl Acad Sci U S A 2021; 118:2020452118. [PMID: 33558240 DOI: 10.1073/pnas.2020452118] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Torsional stress has a significant impact on the structure and stability of the nucleosome. RNA polymerase imposes torsional stress on the DNA in chromatin and unwraps the DNA from the nucleosome to access the genetic information encoded in the DNA. To understand how the torsional stress affects the stability of the nucleosome, we examined the unwrapping of two half superhelical turns of nucleosomal DNA from either end of the DNA under torsional stress with all-atom molecular dynamics simulations. The free energies for unwrapping the DNA indicate that positive stress that overtwists DNA facilitates a large-scale asymmetric unwrapping of the DNA without a large extension of the DNA. During the unwrapping, one end of the DNA was dissociated from H3 and H2A-H2B, while the other end of the DNA stably remained wrapped. The detailed analysis indicates that this asymmetric dissociation is facilitated by the geometry and bendability of the DNA under positive stress. The geometry stabilized the interaction between the major groove of the twisted DNA and the H3 αN-helix, and the straightened DNA destabilized the interaction with H2A-H2B. Under negative stress, the DNA became more bendable and flexible, which facilitated the binding of the unwrapped DNA to the octamer in a stable state. Consequently, we conclude that the torsional stress has a significant impact on the affinity of the DNA and the octamer through the inherent nature of the DNA and can change the accessibility of regulatory proteins.
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Kono H, Sakuraba S, Ishida H. Free energy profile for unwrapping outer superhelical turn of CENP-A nucleosome. Biophys Physicobiol 2019; 16:337-343. [PMID: 31984189 PMCID: PMC6975924 DOI: 10.2142/biophysico.16.0_337] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 08/05/2019] [Indexed: 01/19/2023] Open
Abstract
Eukaryotic genome is packaged in a nucleus in the form of chromatin. The fundamental structural unit of the chromatin is the protein-DNA complex, nucleosome, where DNA of about 150 bp is wrapped around a histone core almost twice. In cellular processes such as gene expression, DNA repair and duplication, the nucleosomal DNA has to be unwrapped. Histone proteins have their variants, indicating there are a variety of constitutions of nucleosomes. These different constitutions are observed in different cellular processes. To investigate differences among nucleosomes, we calculated free energy profiles for unwrapping the outer superhelical turn of CENP-A nucleosome and compared them with those of the canonical nucleosome. The free energy profiles for CENP-A nucleosome suggest that CENP-A nucleosome is the most stable when 16 to 22 bps are unwrapped in total whereas the canonical nucleosome is the most stable when it is fully wrapped. This indicates that the flexible conformation of CENP-A nucleosome is ready to provide binding sites for the structural integrity of the centromere.
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Affiliation(s)
- Hidetoshi Kono
- Molecular Modelling and Simulation Group, Institute for Quantum Life Science (iQLS), National Institutes for Quantum and Radiological Science and Technology, Kizugawa, Kyoto 619-0215 Japan
| | - Shun Sakuraba
- Molecular Modelling and Simulation Group, Institute for Quantum Life Science (iQLS), National Institutes for Quantum and Radiological Science and Technology, Kizugawa, Kyoto 619-0215 Japan
| | - Hisashi Ishida
- Molecular Modelling and Simulation Group, Institute for Quantum Life Science (iQLS), National Institutes for Quantum and Radiological Science and Technology, Kizugawa, Kyoto 619-0215 Japan
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4
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Kawabata T. Detection of cave pockets in large molecules: Spaces into which internal probes can enter, but external probes from outside cannot. Biophys Physicobiol 2019; 16:391-406. [PMID: 31984193 PMCID: PMC6975925 DOI: 10.2142/biophysico.16.0_391] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 08/27/2019] [Indexed: 12/01/2022] Open
Abstract
Geometric features of macromolecular shapes are important for binding with other molecules. Kawabata, T. and Go, N. (2007) defined a pocket as a space into which a small probe can enter, but a large probe cannot. In 2010, mathematical morphology (MM) was introduced to provide a more rigorous definition, and the program GHECOM was developed using the grid-based representation of molecules. This method was simple, but effective in finding the binding sites of small compounds on protein surfaces. Recently, many 3D structures of large macromolecules have been determined to contain large internal hollow spaces. Identification and size estimation of these spaces is important for characterizing their function and stability. Therefore, we employ the MM definition of pocket proposed by Manak, M. (2019)—a space into which an internal probe can enter, but an external probe cannot enter from outside of the macromolecules. This type of space is called a “cave pocket”, and is identified through molecular grid-representation. We define a “cavity” as a space into which a probe can enter, but cannot escape to the outside. Three types of spaces: cavity, pocket, and cave pocket were compared both theoretically and numerically. We proved that a cave pocket includes a pocket, and it is equal to a pocket if no cavity is found. We compared the three types of spaces for a variety of molecules with different-sized spherical probes; cave pockets were more sensitive than pockets for finding almost closed internal holes, allowing for more detailed representations of internal surfaces than cavities provide.
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Affiliation(s)
- Takeshi Kawabata
- Institute for Protein Research, Osaka University, Suita, Osaka 565-0871, Japan
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5
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Insight into Inhibitor Binding in the Eukaryotic Proteasome: Computations of the 20S CP. Int J Mol Sci 2018; 19:ijms19123858. [PMID: 30514002 PMCID: PMC6321098 DOI: 10.3390/ijms19123858] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 11/21/2018] [Accepted: 11/28/2018] [Indexed: 11/16/2022] Open
Abstract
A combination of molecular dynamics (MD) simulations and computational analyses uncovers structural features that may influence substrate passage and exposure to the active sites within the proteolytic chamber of the 20S proteasome core particle (CP). MD simulations of the CP reveal relaxation dynamics in which the CP slowly contracts over the 54 ns sampling period. MD simulations of the SyringolinA (SylA) inhibitor within the proteolytic B 1 ring chamber of the CP indicate that favorable van der Waals and electrostatic interactions account for the predominant association of the inhibitor with the walls of the proteolytic chamber. The time scale required for the inhibitor to travel from the center of the proteolytic chamber to the chamber wall is on the order of 4 ns, accompanied by an average energetic stabilization of approximately -20 kcal/mol.
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Elghobashi-Meinhardt N. Exploring Peptide⁻Solvent Interactions: A Computational Study. Molecules 2018; 23:E2355. [PMID: 30223458 PMCID: PMC6225229 DOI: 10.3390/molecules23092355] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 09/06/2018] [Accepted: 09/10/2018] [Indexed: 11/17/2022] Open
Abstract
The dilemma of reconciling the contradictory evidence regarding the conformation of long solvated peptide chains is the so-called "reconciliation problem". Clues regarding the stability of certain conformations likely lie in the electronic structure at the peptide⁻solvent interface, but the peptide⁻solvent interaction is not fully understood. Here, we study the influence of aqueous solvent on peptide conformations by using classical molecular dynamics (MD) and quantum mechanical/molecular mechanical (QM/MM) energy calculations. The model systems include an 11-residue peptide, X 2 A 7 O 2 (XAO), where X, A, and O denote diaminobutyric acid, alanine, and ornithine, respectively, and a 9-mer (Arg-Pro-Pro-Gly-Phe-Ser-Ala-Phe-Lys). Spectroscopic and MD data present conflicting evidence regarding the structure of XAO in water; some results indicate that XAO adopts a polyproline II (P II ) conformation, whereas other findings suggest that XAO explores a range of conformations. To investigate this contradiction, we present here the results of MD simulations of XAO and the 9-mer in aqueous solution, combined with QM/MM energy calculations.
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Affiliation(s)
- Nadia Elghobashi-Meinhardt
- Theoretical Molecular Biophysics, Department of Physical and Theoretical Chemistry, Institute for Chemistry and Biochemistry, Freie Universität Berlin, Fabeckstr. 36a, 14169 Berlin, Germany.
- Theoretical Molecular Biophysics, Department of Physical and Theoretical Chemistry, Institute for Chemistry and Biochemistry, Freie Universität Berlin, Fabeckstr. 36a, 14169 Berlin, Germany.
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Kono H, Sakuraba S, Ishida H. Free energy profiles for unwrapping the outer superhelical turn of nucleosomal DNA. PLoS Comput Biol 2018; 14:e1006024. [PMID: 29505570 PMCID: PMC5854429 DOI: 10.1371/journal.pcbi.1006024] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 03/15/2018] [Accepted: 02/01/2018] [Indexed: 11/19/2022] Open
Abstract
The eukaryotic genome is packaged into a nucleus in the form of chromatin. The fundamental structural unit of chromatin is a protein-DNA complex, the nucleosome, where 146 or 147 base pairs of DNA wrap 1.75 times around a histone core. To function in cellular processes, however, nucleosomal DNA must be unwrapped. Although this unwrapping has been experimentally investigated, details of the process at an atomic level are not yet well understood. Here, we used molecular dynamics simulation with an enhanced sampling method to calculate the free energy profiles for unwrapping the outer superhelical turn of nucleosomal DNA. A free energy change of about 11.5 kcal/mol for the unwrapping agrees well with values obtained in single molecule experiments. This simulation revealed a variety of conformational states, indicating there are many potential paths to outer superhelicdal turn unwrapping, but the dominant path is likely asymmetric. At one end of the DNA, the first five bps unwrap, after which a second five bps unwrap at the same end with no increase in free energy. The unwrapping then starts at the other end of the DNA, where 10 bps are unwrapped. During further unwrapping of 15 bps, the unwrapping advances at one of the ends, after which the other end of the DNA unwraps to complete the unwrapping of the outer superhelical turn. These results provide insight into the construction, disruption, and repositioning of nucleosomes, which are continuously ongoing during cellular processes.
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Affiliation(s)
- Hidetoshi Kono
- Molecular Modeling and Simulation Group, Department of Quantum Beam Life Science, National Institutes for Quantum and Radiological Science and Technology, Umemidai, Kizugawa, Kyoto, Japan
- * E-mail:
| | - Shun Sakuraba
- Graduate School of Frontier Sciences, The University of Tokyo, Kashiwanoha, Kashiwa, Chiba, Japan
| | - Hisashi Ishida
- Molecular Modeling and Simulation Group, Department of Quantum Beam Life Science, National Institutes for Quantum and Radiological Science and Technology, Umemidai, Kizugawa, Kyoto, Japan
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Ishida H, Kono H. H4 Tails Potentially Produce the Diversity in the Orientation of Two Nucleosomes. Biophys J 2017; 113:978-990. [PMID: 28877499 DOI: 10.1016/j.bpj.2017.07.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 06/29/2017] [Accepted: 07/20/2017] [Indexed: 11/17/2022] Open
Abstract
Histone tails play an important role in internucleosomal interaction and chromatin compaction. To understand how the H4 tails are involved in the internucleosomal interaction, an adaptively biased molecular dynamics simulation of 63 models of two stacked nucleosomes, each with the H4 tails in different locations, was carried out. This simulation generated a variety of orientations of the separated nucleosomes depending on the formation of the H4 tail bridge between the H4 tails and the DNA of the neighboring nucleosomes. For the models that showed distinctive orientations of the two nucleosomes, the free energies of the separation of the nucleosomes were further investigated using umbrella sampling simulations. The attractive force between the nucleosomes was estimated from the free energies; the force when two H4 tail bridges formed varied from 36 to 63 pN, depending on the formation of the H4 tail-bridge and the interfacial interaction, whereas the force reduced to 15-18 pN after either one of the H4 tail bridges had broken, regardless of the conformation of the H4 tail. Additional simulations of the nucleosomes show that when the H4 tail was truncated, the force between the nucleosomes became repulsive (from-3 to -7 pN). We concluded that the H4 tails potentially produce the diversity in the orientation of the two nucleosomes, which would contribute to the polymorphism of the chromatin structure.
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Affiliation(s)
- Hisashi Ishida
- Molecular Modeling and Simulation Group, Department of Quantum Beam Life Science, National Institutes for Quantum and Radiological Science and Technology, Kizugawa, Kyoto, Japan.
| | - Hidetoshi Kono
- Molecular Modeling and Simulation Group, Department of Quantum Beam Life Science, National Institutes for Quantum and Radiological Science and Technology, Kizugawa, Kyoto, Japan
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Gunnoo M, Cazade PA, Galera-Prat A, Nash MA, Czjzek M, Cieplak M, Alvarez B, Aguilar M, Karpol A, Gaub H, Carrión-Vázquez M, Bayer EA, Thompson D. Nanoscale Engineering of Designer Cellulosomes. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2016; 28:5619-47. [PMID: 26748482 DOI: 10.1002/adma.201503948] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 10/01/2015] [Indexed: 05/27/2023]
Abstract
Biocatalysts showcase the upper limit obtainable for high-speed molecular processing and transformation. Efforts to engineer functionality in synthetic nanostructured materials are guided by the increasing knowledge of evolving architectures, which enable controlled molecular motion and precise molecular recognition. The cellulosome is a biological nanomachine, which, as a fundamental component of the plant-digestion machinery from bacterial cells, has a key potential role in the successful development of environmentally-friendly processes to produce biofuels and fine chemicals from the breakdown of biomass waste. Here, the progress toward so-called "designer cellulosomes", which provide an elegant alternative to enzyme cocktails for lignocellulose breakdown, is reviewed. Particular attention is paid to rational design via computational modeling coupled with nanoscale characterization and engineering tools. Remaining challenges and potential routes to industrial application are put forward.
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Affiliation(s)
- Melissabye Gunnoo
- Materials and Surface Science Institute and Department of Physics and Energy, University of Limerick, Limerick, Ireland
| | - Pierre-André Cazade
- Materials and Surface Science Institute and Department of Physics and Energy, University of Limerick, Limerick, Ireland
| | - Albert Galera-Prat
- Instituto Cajal, Consejo Superior de Investigaciones Cientificas (CSIC), IMDEA Nanociencias and CIBERNED, Madrid, Spain
| | - Michael A Nash
- Lehrstuhl für Angewandte Physik and Center for Nanoscience, Ludwig-Maximilians-University, 80799, Munich, Germany
| | - Mirjam Czjzek
- Sorbonne Universités, UPMC, Université Paris 06, and Centre National de la Recherche Scientifique, UMR 8227, Integrative Biology of Marine Models, Station Biologique, de Roscoff, CS 90074, F-29688, Roscoff cedex, Bretagne, France
| | - Marek Cieplak
- Laboratory of Biological Physics, Institute of Physics, Polish Academy of Sciences, Warsaw, Poland
| | - Beatriz Alvarez
- Biopolis S.L., Parc Científic de la Universitat de Valencia, Edificio 2, C/Catedrático Agustín Escardino 9, 46980, Paterna (Valencia), Spain
| | - Marina Aguilar
- Abengoa, S.A., Palmas Altas, Calle Energía Solar nº 1, 41014, Seville, Spain
| | - Alon Karpol
- Designer Energy Ltd., 2 Bergman St., Tamar Science Park, Rehovot, 7670504, Israel
| | - Hermann Gaub
- Lehrstuhl für Angewandte Physik and Center for Nanoscience, Ludwig-Maximilians-University, 80799, Munich, Germany
| | - Mariano Carrión-Vázquez
- Instituto Cajal, Consejo Superior de Investigaciones Cientificas (CSIC), IMDEA Nanociencias and CIBERNED, Madrid, Spain
| | - Edward A Bayer
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Damien Thompson
- Materials and Surface Science Institute and Department of Physics and Energy, University of Limerick, Limerick, Ireland
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Ishida H, Matsumoto A. Mechanism for verification of mismatched and homoduplex DNAs by nucleotides-bound MutS analyzed by molecular dynamics simulations. Proteins 2016; 84:1287-303. [PMID: 27238299 DOI: 10.1002/prot.25077] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 05/13/2016] [Accepted: 05/24/2016] [Indexed: 11/10/2022]
Abstract
In order to understand how MutS recognizes mismatched DNA and induces the reaction of DNA repair using ATP, the dynamics of the complexes of MutS (bound to the ADP and ATP nucleotides, or not) and DNA (with mismatched and matched base-pairs) were investigated using molecular dynamics simulations. As for DNA, the structure of the base-pairs of the homoduplex DNA which interacted with the DNA recognition site of MutS was intermittently disturbed, indicating that the homoduplex DNA was unstable. As for MutS, the disordered loops in the ATPase domains, which are considered to be necessary for the induction of DNA repair, were close to (away from) the nucleotide-binding sites in the ATPase domains when the nucleotides were (not) bound to MutS. This indicates that the ATPase domains changed their structural stability upon ATP binding using the disordered loop. Conformational analysis by principal component analysis showed that the nucleotide binding changed modes which have structurally solid ATPase domains and the large bending motion of the DNA from higher to lower frequencies. In the MutS-mismatched DNA complex bound to two nucleotides, the bending motion of the DNA at low frequency modes may play a role in triggering the formation of the sliding clamp for the following DNA-repair reaction step. Moreover, MM-PBSA/GBSA showed that the MutS-homoduplex DNA complex bound to two nucleotides was unstable because of the unfavorable interactions between MutS and DNA. This would trigger the ATP hydrolysis or separation of MutS and DNA to continue searching for mismatch base-pairs. Proteins 2016; 84:1287-1303. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Hisashi Ishida
- Quantum Beam Science Research Directorate, National Institutes for Quantum and Radiological Science and Technology, 8-1-7 Umemidai Kizugawa-Shi, Kyoto, 619-0215, Japan
| | - Atsushi Matsumoto
- Quantum Beam Science Research Directorate, National Institutes for Quantum and Radiological Science and Technology, 8-1-7 Umemidai Kizugawa-Shi, Kyoto, 619-0215, Japan
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Ishida H, Matsumoto A. Free-energy landscape of reverse tRNA translocation through the ribosome analyzed by electron microscopy density maps and molecular dynamics simulations. PLoS One 2014; 9:e101951. [PMID: 24999999 PMCID: PMC4084982 DOI: 10.1371/journal.pone.0101951] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 06/12/2014] [Indexed: 01/11/2023] Open
Abstract
To understand the mechanism of reverse tRNA translocation in the ribosome, all-atom molecular dynamics simulations of the ribosome-tRNAs-mRNA-EFG complex were performed. The complex at the post-translocational state was directed towards the translocational and pre-translocational states by fitting the complex into cryo-EM density maps. Between a series of the fitting simulations, umbrella sampling simulations were performed to obtain the free-energy landscape. Multistep structural changes, such as a ratchet-like motion and rotation of the head of the small subunit were observed. The free-energy landscape showed that there were two main free-energy barriers: one between the post-translocational and intermediate states, and the other between the pre-translocational and intermediate states. The former corresponded to a clockwise rotation, which was coupled to the movement of P-tRNA over the P/E-gate made of G1338, A1339 and A790 in the small subunit. The latter corresponded to an anticlockwise rotation of the head, which was coupled to the location of the two tRNAs in the hybrid state. This indicates that the coupled motion of the head rotation and tRNA translocation plays an important role in opening and closing of the P/E-gate during the ratchet-like movement in the ribosome. Conformational change of EF-G was interpreted to be the result of the combination of the external motion by L12 around an axis passing near the sarcin-ricin loop, and internal hinge-bending motion. These motions contributed to the movement of domain IV of EF-G to maintain its interaction with A/P-tRNA.
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Affiliation(s)
- Hisashi Ishida
- Quantum Beam Science Directorate and Center for Computational Science and e-Systems, Japan Atomic Energy Agency, Kyoto, Japan
- * E-mail:
| | - Atsushi Matsumoto
- Quantum Beam Science Directorate and Center for Computational Science and e-Systems, Japan Atomic Energy Agency, Kyoto, Japan
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