1
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Shadman H, Ziebarth JD, Gallops CE, Luo R, Li Z, Chen HF, Wang Y. Map conformational landscapes of intrinsically disordered proteins with polymer physics quantities. Biophys J 2024; 123:1253-1263. [PMID: 38615193 PMCID: PMC11140466 DOI: 10.1016/j.bpj.2024.04.010] [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: 10/30/2023] [Revised: 02/20/2024] [Accepted: 04/10/2024] [Indexed: 04/15/2024] Open
Abstract
Disordered proteins are conformationally flexible proteins that are biologically important and have been implicated in devastating diseases such as Alzheimer's disease and cancer. Unlike stably folded structured proteins, disordered proteins sample a range of different conformations that needs to be accounted for. Here, we treat disordered proteins as polymer chains, and compute a dimensionless quantity called instantaneous shape ratio (Rs), as Rs = Ree2/Rg2, where Ree is end-to-end distance and Rg is radius of gyration. Extended protein conformations tend to have high Ree compared with Rg, and thus have high Rs values, whereas compact conformations have smaller Rs values. We use a scatter plot of Rs (representing shape) against Rg (representing size) as a simple map of conformational landscapes. We first examine the conformational landscape of simple polymer models such as Random Walk, Self-Avoiding Walk, and Gaussian Walk (GW), and we notice that all protein/polymer maps lie within the boundaries of the GW map. We thus use the GW map as a reference and, to assess conformational diversity, we compute the fraction of the GW conformations (fC) covered by each protein/polymer. Disordered proteins all have high fC scores, consistent with their disordered nature. Each disordered protein accesses a different region of the reference map, revealing differences in their conformational ensembles. We additionally examine the conformational maps of the nonviral gene delivery vector polyethyleneimine at various protonation states, and find that they resemble disordered proteins, with coverage of the reference map decreasing with increasing protonation state, indicating decreasing conformational diversity. We propose that our method of combining Rs and Rg in a scatter plot generates a simple, meaningful map of the conformational landscape of a disordered protein, which in turn can be used to assess conformational diversity of disordered proteins.
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Affiliation(s)
- Hossain Shadman
- Department of Chemistry, The University of Memphis, Memphis, Tennessee
| | - Jesse D Ziebarth
- Department of Chemistry, The University of Memphis, Memphis, Tennessee
| | - Caleb E Gallops
- Department of Chemistry, The University of Memphis, Memphis, Tennessee
| | - Ray Luo
- Chemical and Materials Physics Graduate Program, Departments of Molecular Biology and Biochemistry, Chemical and Biomolecular Engineering, Materials Science and Engineering, and Biomedical Engineering, University of California, Irvine, Irvine, California
| | - Zhengxin Li
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, Department of Bioinformatics and Biostatistics, National Experimental Teaching Center for Life Sciences and Biotechnology, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Hai-Feng Chen
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, Department of Bioinformatics and Biostatistics, National Experimental Teaching Center for Life Sciences and Biotechnology, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Yongmei Wang
- Department of Chemistry, The University of Memphis, Memphis, Tennessee.
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2
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Bakker M, Sørensen HV, Skepö M. Exploring the Role of Globular Domain Locations on an Intrinsically Disordered Region of p53: A Molecular Dynamics Investigation. J Chem Theory Comput 2024; 20:1423-1433. [PMID: 38230670 PMCID: PMC10867847 DOI: 10.1021/acs.jctc.3c00971] [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: 09/05/2023] [Revised: 12/28/2023] [Accepted: 12/29/2023] [Indexed: 01/18/2024]
Abstract
The pre-tetramerization loop (PTL) of the human tumor suppressor protein p53 is an intrinsically disordered region (IDR) necessary for the tetramerization process, and its flexibility contributes to the essential conformational changes needed. Although the IDR can be accurately simulated in the traditional manner of molecular dynamics (MD) with the end-to-end distance (EEdist) unhindered, we sought to explore the effects of restraining the EEdist to the values predicted by electron microscopy (EM) and other distances. Simulating the PTL trajectory with a restrained EEdist , we found an increased agreement of nuclear magnetic resonance (NMR) chemical shifts with experiments. Additionally, we observed a plethora of secondary structures and contacts that only appear when the trajectory is restrained. Our findings expand the understanding of the tetramerization of p53 and provide insight into how mutations could make the protein impotent. In particular, our findings demonstrate the importance of restraining the EEdist in studying IDRs and how their conformations change under different conditions. Our results provide a better understanding of the PTL and the conformational dynamics of IDRs in general, which are useful for further studies regarding mutations and their effects on the activity of p53.
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Affiliation(s)
- Michael
J. Bakker
- Faculty
of Pharmacy in Hradec Králové, Charles University, Akademika Heyrovského 1203/8, 500 05 Hradec Králové, Czech Republic
- Division
of Computational Chemistry, Department of Chemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
| | - Henrik V. Sørensen
- Division
of Computational Chemistry, Department of Chemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
- MAX
IV Laboratory, Lund Institute of Advanced
Neutron and X-ray Science, Scheelevägen 19, SE-223 770 Lund, Sweden
| | - Marie Skepö
- Division
of Computational Chemistry, Department of Chemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
- LINXS
- Institute of Advanced Neutron and X-ray Science, Scheelevägen 19, SE-233 70 Lund, Sweden
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3
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Al-Shabib N, Khan JM, Al-Amri AM, Malik A, Husain FM, Sharma P, Emerson A, Kumar V, Sen P. Interaction Mechanism between α-Lactalbumin and Caffeic Acid: A Multispectroscopic and Molecular Docking Study. ACS OMEGA 2023; 8:19853-19861. [PMID: 37305235 PMCID: PMC10249380 DOI: 10.1021/acsomega.3c01755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 05/08/2023] [Indexed: 06/13/2023]
Abstract
Caffeic acid (CA) is a phenolic acid found in a variety of foods. In this study, the interaction mechanism between α-lactalbumin (ALA) and CA was explored with the use of spectroscopic and computational techniques. The Stern-Volmer quenching constant data suggest a static mode of quenching between CA and ALA, depicting a gradual decrease in quenching constants with temperature rise. The binding constant, Gibbs free energy, enthalpy, and entropy values at 288, 298, and 310 K were calculated, and the obtained values suggest that the reaction is spontaneous and exothermic. Both in vitro and in silico studies show that hydrogen bonding is the dominant force in the CA-ALA interaction. Ser112 and Lys108 of ALA are predicted to form three hydrogen bonds with CA. The UV-visible spectroscopy measurements demonstrated that the absorbance peak A280nm increased after addition of CA due to conformational change. The secondary structure of ALA was also slightly modified due to CA interaction. The circular dichroism (CD) studies showed that ALA gains more α-helical structure in response to increasing concentration of CA. The surface hydrophobicity of ALA is not changed in the presence of ethanol and CA. The present findings shown herein are helpful in understanding the binding mechanism of CA with whey proteins for the dairy processing industry and food nutrition security.
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Affiliation(s)
- Nasser
Abdulatif Al-Shabib
- College
of Food and Agriculture Sciences, Department of Food and Nutrition, King Saud University, Riyadh 11451, Saudi Arabia
| | - Javed Masood Khan
- College
of Food and Agriculture Sciences, Department of Food and Nutrition, King Saud University, Riyadh 11451, Saudi Arabia
| | - Abdulaziz M. Al-Amri
- College
of Science, Department of Biochemistry, King Saud University, Riyadh 11451, Saudi Arabia
| | - Ajamaluddin Malik
- College
of Science, Department of Biochemistry, King Saud University, Riyadh 11451, Saudi Arabia
| | - Fohad Mabood Husain
- College
of Food and Agriculture Sciences, Department of Food and Nutrition, King Saud University, Riyadh 11451, Saudi Arabia
| | - Prerna Sharma
- Geisinger
Commonwealth School of Medicine, Scranton, Pennsylvania 18509-3240, United States
| | - Arnold Emerson
- Department
of Biotechnology, School of Bio Sciences and Technology, VIT University, Vellore, Tamil Nadu 632014, India
| | - Vijay Kumar
- Himalayan
School of Biosciences, Swami Rama Himalayan
University, Dehradun, Uttarakhand 248016, India
| | - Priyankar Sen
- Centre for
Bioseparation Technology, VIT University, Vellore, Tamil Nadu 632014, India
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4
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Shadman H, Gallops CE, Ziebarth JD, DeRouchey JE, Wang Y. Exploring Structures and Dynamics of Protamine Molecules through Molecular Dynamics Simulations. ACS OMEGA 2022; 7:42083-42095. [PMID: 36440140 PMCID: PMC9685783 DOI: 10.1021/acsomega.2c04227] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 10/18/2022] [Indexed: 06/16/2023]
Abstract
Protamines are arginine-rich proteins that condense DNA in sperm. Despite their importance in reproduction, information on protamine structure is scarce. We, therefore, used molecular dynamics to examine the structures of salmon, bull P1, and human P1 protamines. The sizes and shapes of each protamine varied widely, indicating that they were disordered with structures covering a broad conformational landscape, from hairpin loop structures to extended coils. Despite their general disorder, the protamines did form secondary structures, including helices and hairpin loops. In eutherians, hairpins may promote disulfide bonding that facilitates protamine-DNA condensation, but the specifics of this bonding is not well established. We examined inter-residue distances in the simulations to predict residue pairs likely to form intramolecular bonds, leading to the identification of bonding pairs consistent with previous results in bull and human. These results support a model for eutherian protamine structures where a highly charged center is surrounded by disulfide-bond-stabilized loops.
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Affiliation(s)
- Hossain Shadman
- Department
of Chemistry, The University of Memphis, Memphis, Tennessee38154, United States
| | - Caleb Edward Gallops
- Department
of Chemistry, The University of Memphis, Memphis, Tennessee38154, United States
| | - Jesse D. Ziebarth
- Department
of Chemistry, The University of Memphis, Memphis, Tennessee38154, United States
| | - Jason E. DeRouchey
- Department
of Chemistry, The University of Kentucky, Lexington, Kentucky40506, United States
| | - Yongmei Wang
- Department
of Chemistry, The University of Memphis, Memphis, Tennessee38154, United States
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5
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Bhattarai A, Emerson IA. Exploring the conformational dynamics and flexibility of intrinsically disordered HIV-1 Nef protein using molecular dynamic network approaches. 3 Biotech 2021; 11:156. [PMID: 33747706 DOI: 10.1007/s13205-021-02698-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 02/19/2021] [Indexed: 10/22/2022] Open
Abstract
Intrinsically disordered proteins represent a class of proteins that lack fixed and well-defined three-dimensional structures in solution. HIV-1 Nef is an intrinsically disordered peripheral membrane protein involved in the replication and pathogenesis of HIV-1 infection. Nef controls expression levels of cell surface CD4 molecules that are essential for adaptive immunity. Despite the lack of fixed and stable structures, Nef physically interacts with the host cellular proteins (AP-1/MHC-I) and modulates intracellular trafficking pathways. Therefore, it is essential to understand how this dynamic conformational flexibility affects Nef structures and function. In this study, we combined all-atom molecular dynamics (MD) simulations and dynamic network approaches to better understand the structure and dynamics of Nef in two different forms, the free unbound and the bound state. Using the MD simulation approach, we show that the intrinsically disordered Nef exhibit a large dynamic field with more atomic fluctuations and lesser thermodynamic stability in the unbound conditions. The conformations of Nef change over time, and this protein remains more compact, folded, and stable in the bound form. The dynamic network analysis revealed regions of the protein capable of modulating the conformational behavior of the disordered Nef. The average betweenness centrality (BC) unveiled residues that are critical for mediating protein-protein interactions. The average shortest path length (L) and the perturbation response scanning exposed residues that are likely to be important in steering protein conformational changes. Overall, the study demonstrates how all-atom MD simulations combined with the dynamic network approach can be used to gain further insights into the structure and dynamics-function relationship of intrinsically disordered HIV-1 Nef. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s13205-021-02698-8.
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6
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Wang W. Recent advances in atomic molecular dynamics simulation of intrinsically disordered proteins. Phys Chem Chem Phys 2021; 23:777-784. [PMID: 33355572 DOI: 10.1039/d0cp05818a] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Intrinsically disordered proteins (IDPs) play important roles in cellular functions. The inherent structural heterogeneity of IDPs makes the high-resolution experimental characterization of IDPs extremely difficult. Molecular dynamics (MD) simulation could provide the atomic-level description of the structural and dynamic properties of IDPs. This perspective reviews the recent progress in atomic MD simulation studies of IDPs, including the development of force fields and sampling methods, as well as applications in IDP-involved protein-protein interactions. The employment of large-scale simulations and advanced sampling techniques allows more accurate estimation of the thermodynamics and kinetics of IDP-mediated protein interactions, and the holistic landscape of the binding process of IDPs is emerging.
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Affiliation(s)
- Wenning Wang
- Department of Chemistry, Multiscale Research Institute of Complex Systems and Institute of Biomedical Sciences, Fudan University, Shanghai 200438, China.
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7
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Clemens L, Dushek O, Allard J. Intrinsic Disorder in the T Cell Receptor Creates Cooperativity and Controls ZAP70 Binding. Biophys J 2020; 120:379-392. [PMID: 33285117 PMCID: PMC7840419 DOI: 10.1016/j.bpj.2020.11.2266] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 10/24/2020] [Accepted: 11/19/2020] [Indexed: 12/31/2022] Open
Abstract
Many immunoreceptors have cytoplasmic domains that are intrinsically disordered (i.e., have high configurational entropy), have multiple sites of posttranslational modification (e.g., tyrosine phosphorylation), and participate in nonlinear signaling pathways (e.g., exhibiting switch-like behavior). Several hypotheses to explain the origin of these nonlinearities fall under the broad hypothesis that modification at one site changes the immunoreceptor’s entropy, which in turn changes further modification dynamics. Here, we use coarse-grain simulation to study three scenarios, all related to the chains that constitute the T cell receptor (TCR). We find that first, if phosphorylation induces local changes in the flexibility of the TCR ζ-chain, this naturally leads to rate enhancements and cooperativity. Second, we find that TCR CD3ɛ can provide a switch by modulating its residence in the plasma membrane. By constraining our model to be consistent with the previous observation that both basic residues and phosphorylation control membrane residence, we find that there is only a moderate rate enhancement of 10% between first and subsequent phosphorylation events. Third, we find that volume constraints do not limit the number of ZAP70s that can bind the TCR but that entropic penalties lead to a 200-fold decrease in binding rate by the seventh ZAP70, potentially explaining the observation that each TCR has around six ZAP70 molecules bound after receptor triggering. In all three scenarios, our results demonstrate that phenomena that change an immunoreceptor chain’s entropy (stiffening, confinement to a membrane, and multiple simultaneous binding) can lead to nonlinearities (rate enhancement, switching, and negative cooperativity) in how the receptor participates in signaling. These polymer-entropy-driven nonlinearities may augment the nonlinearities that arise from, e.g., kinetic proofreading and cluster formation. They also suggest different design strategies for engineered receptors, e.g., whether or not to put signaling modules on one chain or multiple clustered chains.
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Affiliation(s)
- Lara Clemens
- Center for Complex Biological Systems, University of California Irvine, Irvine, California
| | - Omer Dushek
- Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Jun Allard
- Center for Complex Biological Systems, University of California Irvine, Irvine, California; Department of Mathematics and Department of Physics and Astronomy, University of California Irvine, Irvine, California.
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8
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Shabane PS, Onufriev AV. Significant compaction of H4 histone tail upon charge neutralization by acetylation and its mimics, possible effects on chromatin structure. J Mol Biol 2020; 433:166683. [PMID: 33096105 DOI: 10.1016/j.jmb.2020.10.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 09/30/2020] [Accepted: 10/13/2020] [Indexed: 10/23/2022]
Abstract
The intrinsically disordered, positively charged H4 histone tail is important for chromatin structure and function. We have explored conformational ensembles of human H4 tail in solution, with varying levels of charge neutralization via acetylation or amino-acid substitutions such as K→Q. We have employed an explicit water model shown recently to be well suited for simulations of intrinsically disordered proteins. Upon progressive neutralization of the H4, its radius of gyration decreases linearly with the tail charge q, the trend is explained using a simple polymer model. While the wild type state (q=+8) is essentially a random coil, hyper-acetylated H4 (q=+3) is virtually as compact and stable as a globular protein of the same number of amino-acids. Conformational ensembles of acetylated H4 match the corresponding K→X substitutions only approximately: based on the ensemble similarity, we propose K→M as a possible alternative to the commonly used K→Q. Possible effects of the H4 tail compaction on chromatin structure are discussed within a qualitative model in which the chromatin is highly heterogeneous, easily inter-converting between various structural forms. We predict that upon progressive charge neutralization of the H4 tail, the least compact sub-states of chromatin de-condense first, followed by de-condensation of more compact structures, e.g. those that harbor a high fraction of stacked di-nucleosomes. The predicted hierarchy of DNA accessibility increase upon progressive acetylation of H4 might be utilized by the cell for selective DNA accessibility control.
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Affiliation(s)
| | - Alexey V Onufriev
- Departments of Computer Science, Virginia Tech, Blacksburg, VA 24060, United States; Department of Physics, Virginia Tech, Blacksburg, VA 24060, United States; Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA 24061, USA.
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9
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Dynamic conformational flexibility and molecular interactions of intrinsically disordered proteins. J Biosci 2020. [DOI: 10.1007/s12038-020-0010-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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10
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Lohia R, Salari R, Brannigan G. Sequence specificity despite intrinsic disorder: How a disease-associated Val/Met polymorphism rearranges tertiary interactions in a long disordered protein. PLoS Comput Biol 2019; 15:e1007390. [PMID: 31626641 PMCID: PMC6821141 DOI: 10.1371/journal.pcbi.1007390] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 10/30/2019] [Accepted: 09/10/2019] [Indexed: 11/24/2022] Open
Abstract
The role of electrostatic interactions and mutations that change charge states in intrinsically disordered proteins (IDPs) is well-established, but many disease-associated mutations in IDPs are charge-neutral. The Val66Met single nucleotide polymorphism (SNP) in precursor brain-derived neurotrophic factor (BDNF) is one of the earliest SNPs to be associated with neuropsychiatric disorders, and the underlying molecular mechanism is unknown. Here we report on over 250 μs of fully-atomistic, explicit solvent, temperature replica-exchange molecular dynamics (MD) simulations of the 91 residue BDNF prodomain, for both the V66 and M66 sequence. The simulations were able to correctly reproduce the location of both local and non-local secondary structure changes due to the Val66Met mutation, when compared with NMR spectroscopy. We find that the change in local structure is mediated via entropic and sequence specific effects. We developed a hierarchical sequence-based framework for analysis and conceptualization, which first identifies “blobs” of 4-15 residues representing local globular regions or linkers. We use this framework within a novel test for enrichment of higher-order (tertiary) structure in disordered proteins; the size and shape of each blob is extracted from MD simulation of the real protein (RP), and used to parameterize a self-avoiding heterogenous polymer (SAHP). The SAHP version of the BDNF prodomain suggested a protein segmented into three regions, with a central long, highly disordered polyampholyte linker separating two globular regions. This effective segmentation was also observed in full simulations of the RP, but the Val66Met substitution significantly increased interactions across the linker, as well as the number of participating residues. The Val66Met substitution replaces β-bridging between V66 and V94 (on either side of the linker) with specific side-chain interactions between M66 and M95. The protein backbone in the vicinity of M95 is then free to form β-bridges with residues 31-41 near the N-terminus, which condenses the protein. A significant role for Met/Met interactions is consistent with previously-observed non-local effects of the Val66Met SNP, as well as established interactions between the Met66 sequence and a Met-rich receptor that initiates neuronal growth cone retraction. Intrinsically disordered proteins are proteins that have no well-defined structure in at least one functional form. Mutations in one amino acid may still affect their function significantly, especially in subtle ways with cumulative adverse effects on health. Here we report on molecular dynamics simulations of a protein that is critical for neuronal health throughout adulthood (brain-derived neurotrophic factor). We investigate the effects of a mutation carried by 30% of human population, which has been widely studied for its association with aging-related and stress-related disorders, reduced volume of the hippocampus, and variations in episodic memory. We identify a molecular mechanism in which the mutation may change the global conformations of the protein and its ability to bind to receptors.
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Affiliation(s)
- Ruchi Lohia
- Center for Computational and Integrative Biology, Rutgers University, Camden, New Jersey, United States of America
| | - Reza Salari
- Center for Computational and Integrative Biology, Rutgers University, Camden, New Jersey, United States of America
| | - Grace Brannigan
- Center for Computational and Integrative Biology, Rutgers University, Camden, New Jersey, United States of America
- Department of Physics, Rutgers University, Camden, New Jersey, United States of America
- * E-mail:
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11
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Davey NE, Babu MM, Blackledge M, Bridge A, Capella-Gutierrez S, Dosztanyi Z, Drysdale R, Edwards RJ, Elofsson A, Felli IC, Gibson TJ, Gutmanas A, Hancock JM, Harrow J, Higgins D, Jeffries CM, Le Mercier P, Mészáros B, Necci M, Notredame C, Orchard S, Ouzounis CA, Pancsa R, Papaleo E, Pierattelli R, Piovesan D, Promponas VJ, Ruch P, Rustici G, Romero P, Sarntivijai S, Saunders G, Schuler B, Sharan M, Shields DC, Sussman JL, Tedds JA, Tompa P, Turewicz M, Vondrasek J, Vranken WF, Wallace BA, Wichapong K, Tosatto SCE. An intrinsically disordered proteins community for ELIXIR. F1000Res 2019; 8. [PMID: 31824649 PMCID: PMC6880265 DOI: 10.12688/f1000research.20136.1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/18/2019] [Indexed: 01/20/2023] Open
Abstract
Intrinsically disordered proteins (IDPs) and intrinsically disordered regions (IDRs) are now recognised as major determinants in cellular regulation. This white paper presents a roadmap for future e-infrastructure developments in the field of IDP research within the ELIXIR framework. The goal of these developments is to drive the creation of high-quality tools and resources to support the identification, analysis and functional characterisation of IDPs. The roadmap is the result of a workshop titled “An intrinsically disordered protein user community proposal for ELIXIR” held at the University of Padua. The workshop, and further consultation with the members of the wider IDP community, identified the key priority areas for the roadmap including the development of standards for data annotation, storage and dissemination; integration of IDP data into the ELIXIR Core Data Resources; and the creation of benchmarking criteria for IDP-related software. Here, we discuss these areas of priority, how they can be implemented in cooperation with the ELIXIR platforms, and their connections to existing ELIXIR Communities and international consortia. The article provides a preliminary blueprint for an IDP Community in ELIXIR and is an appeal to identify and involve new stakeholders.
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Affiliation(s)
- Norman E Davey
- Division of Cancer Biology, Institute of Cancer Research, UK, London, SW3 6JB, UK
| | - M Madan Babu
- MRC Laboratory of Molecular Biology,, Cambridge, CB2 0QH, UK
| | - Martin Blackledge
- Institut de Biologie Structurale, Université Grenoble Alpes, Grenoble, 38000, France
| | - Alan Bridge
- Swiss-Prot Group, SIB Swiss Institute of Bioinformatics, Geneva, Switzerland
| | | | - Zsuzsanna Dosztanyi
- Department of Biochemistry, Eötvös Loránd University, Budapest, H-1117, Hungary
| | | | - Richard J Edwards
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Arne Elofsson
- Department of Biochemistry and Biophysics and Science for Life Laboratory, Stockholm University, Stockholm, Sweden
| | - Isabella C Felli
- Department of Chemistry and CERM "Ugo Schiff", University of Florence, Florence, Italy
| | - Toby J Gibson
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Aleksandras Gutmanas
- Protein Data Bank in Europe, European Bioinformatics Institute (EMBL-EBI), European Molecular Biology Laboratory, Cambridge, CB10 1SD, UK
| | - John M Hancock
- ELIXIR Hub, Wellcome Genome Campus, Cambridge, CB10 1SD, UK
| | - Jen Harrow
- ELIXIR Hub, Wellcome Genome Campus, Cambridge, CB10 1SD, UK
| | - Desmond Higgins
- Conway Institute of Biomolecular & Biomedical Research, University College Dublin, Belfield, Dublin, D4, Ireland
| | - Cy M Jeffries
- European Molecular Biology Laboratory, Hamburg, Germany
| | - Philippe Le Mercier
- Swiss-Prot Group, SIB Swiss Institute of Bioinformatics, Geneva, Switzerland
| | - Balint Mészáros
- Department of Biochemistry, Eötvös Loránd University, Budapest, H-1117, Hungary
| | - Marco Necci
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Cedric Notredame
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, 08003, Spain.,Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Sandra Orchard
- European Bioinformatics Institute (EMBL-EBI), European Molecular Biology Laboratory, Cambridge, CB10 1SD, UK
| | - Christos A Ouzounis
- BCPL-CPERI, Centre for Research & Technology Hellas (CERTH), Thessalonica, 57001, Greece
| | - Rita Pancsa
- Institute of Enzymology, Research Centre for Natural Sciences of the Hungarian Academy of Sciences, Budapest, H-1117, Hungary
| | - Elena Papaleo
- Computational Biology Laboratory, Danish Cancer Society Research Center, Copenhagen, 2100, Denmark
| | - Roberta Pierattelli
- Department of Chemistry and CERM "Ugo Schiff", University of Florence, Florence, Italy
| | - Damiano Piovesan
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Vasilis J Promponas
- Bioinformatics Research Laboratory, Department of Biological Sciences, University of Cyprus, Nicosia, CY-1678, Cyprus
| | - Patrick Ruch
- HES-SO/HEG and SIB Text Mining, Swiss Institute of Bioinformatics, Geneva, Switzerland
| | - Gabriella Rustici
- Department of Genetics, University of Cambridge, Cambridge, CB2 3EH, UK
| | - Pedro Romero
- University of Wisconsin-Madison, Madison, WI, 53706-1544, USA
| | | | - Gary Saunders
- ELIXIR Hub, Wellcome Genome Campus, Cambridge, CB10 1SD, UK
| | - Benjamin Schuler
- Department of Biochemistry, University of Zurich, Zurich, Switzerland
| | - Malvika Sharan
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Denis C Shields
- Conway Institute of Biomolecular & Biomedical Research, University College Dublin, Belfield, Dublin, D4, Ireland
| | - Joel L Sussman
- Department of Structural Biology and the Israel Structural Proteomics, Center (ISPC), Weizmann Institute of Science, Reḥovot, 7610001, Israel
| | | | - Peter Tompa
- VIB Center for Structural Biology (CSB), VIB Flemish Institute for Biotechnology, Brussels, 1050, Belgium
| | - Michael Turewicz
- Faculty of Medicine, Medizinisches Proteom-Center, Ruhr University Bochum, GesundheitsCampus 4, Bochum, 44801, Germany
| | - Jiri Vondrasek
- Institute of Organic Chemistry and Biochemistry, CAS, Prague, Czech Republic
| | - Wim F Vranken
- VUB/ULB Interuniversity Institute of Bioinformatics in Brussels and Structural Biology Brussels, Vrije Universiteit Brussel, Brussels, B-1050, Belgium
| | - Bonnie Ann Wallace
- Institute of Structural and Molecular Biology, Birkbeck College, University of London, London, WC1H 0HA, UK
| | - Kanin Wichapong
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
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12
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Cannon JF. Novel phosphorylation-dependent regulation in an unstructured protein. Proteins 2019; 88:366-384. [PMID: 31512287 DOI: 10.1002/prot.25812] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 07/15/2019] [Accepted: 09/04/2019] [Indexed: 12/15/2022]
Abstract
This work explores how phosphorylation of an unstructured protein region in inhibitor-2 (I2) regulates protein phosphatase-1 (PP1) enzyme activity using molecular dynamics (MD). Free I2 is largely unstructured; however, when bound to PP1, three segments adopt a stable structure. In particular, an I2 helix (i-helix) blocks the PP1 active site and inhibits phosphatase activity. I2 phosphorylation in the PP1-I2 complex activates phosphatase activity without I2 dissociation. The I2 Thr74 regulatory phosphorylation site is in an unstructured domain in PP1-I2. PP1-I2 MD demonstrated that I2 phosphorylation promotes early steps of PP1-I2 activation in explicit solvent models. Moreover, phosphorylation-dependent activation occurred in PP1-I2 complexes derived from I2 orthologs with diverse sequences from human, yeast, worm, and protozoa. This system allowed exploration of features of the 73-residue unstructured human I2 domain critical for phosphorylation-dependent activation. These studies revealed that components of I2 unstructured domain are strategically positioned for phosphorylation responsiveness including a transient α-helix. There was no evidence that electrostatic interactions of I2 phosphothreonine74 influenced PP1-I2 activation. Instead, phosphorylation altered the conformation of residues around Thr74. Phosphorylation uncurled the distance between I2 residues Glu71 to Tyr76 to promote PP1-I2 activation, whereas reduced distances reduced activation. This I2 residue Glu71 to Tyr76 distance distribution, independently from Thr74 phosphorylation, controls I2 i-helix displacement from the PP1 active site leading to PP1-I2 activation.
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Affiliation(s)
- John F Cannon
- Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, Missouri
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13
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Kasahara K, Terazawa H, Takahashi T, Higo J. Studies on Molecular Dynamics of Intrinsically Disordered Proteins and Their Fuzzy Complexes: A Mini-Review. Comput Struct Biotechnol J 2019; 17:712-720. [PMID: 31303975 PMCID: PMC6603302 DOI: 10.1016/j.csbj.2019.06.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 05/29/2019] [Accepted: 06/11/2019] [Indexed: 11/19/2022] Open
Abstract
The molecular dynamics (MD) method is a promising approach toward elucidating the molecular mechanisms of intrinsically disordered regions (IDRs) of proteins and their fuzzy complexes. This mini-review introduces recent studies that apply MD simulations to investigate the molecular recognition of IDRs. Firstly, methodological issues by which MD simulations treat IDRs, such as developing force fields, treating periodic boundary conditions, and enhanced sampling approaches, are discussed. Then, several examples of the applications of MD to investigate molecular interactions of IDRs in terms of the two kinds of complex formations; coupled-folding and binding and fuzzy complex. MD simulations provide insight into the molecular mechanisms of these binding processes by sampling conformational ensembles of flexible IDRs. In particular, we focused on all-atom explicit-solvent MD simulations except for studies of higher-order assembly of IDRs. Recent advances in MD methods, and computational power make it possible to dissect the molecular details of realistic molecular systems involving the dynamic behavior of IDRs.
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Affiliation(s)
- Kota Kasahara
- College of Life Sciences, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga 525-8577, Japan
- Corresponding author.
| | - Hiroki Terazawa
- Graduate School of Life Sciences, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga 525-8577, Japan
| | - Takuya Takahashi
- College of Life Sciences, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga 525-8577, Japan
| | - Junichi Higo
- Graduate School of Simulation Studies, University of Hyogo, 7-1-28 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan
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14
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The Structural and Functional Diversity of Intrinsically Disordered Regions in Transmembrane Proteins. J Membr Biol 2019; 252:273-292. [DOI: 10.1007/s00232-019-00069-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 05/17/2019] [Indexed: 10/26/2022]
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15
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Shabane PS, Izadi S, Onufriev AV. General Purpose Water Model Can Improve Atomistic Simulations of Intrinsically Disordered Proteins. J Chem Theory Comput 2019; 15:2620-2634. [PMID: 30865832 DOI: 10.1021/acs.jctc.8b01123] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Unconstrained atomistic simulations of intrinsically disordered proteins and peptides (IDP) remain a challenge: widely used, "general purpose" water models tend to favor overly compact structures relative to experiment. Here we have performed a total of 93 μs of unrestrained MD simulations to explore, in the context of IDPs, a recently developed "general-purpose" 4-point rigid water model OPC, which describes liquid state of water close to experiment. We demonstrate that OPC, together with a popular AMBER force field ff99SB, offers a noticeable improvement over TIP3P in producing more realistic structural ensembles of three common IDPs benchmarks: 55-residue apo N-terminal zinc-binding domain of HIV-1 integrase ("protein IN"), amyloid β-peptide (Aβ42) (residues 1-42), and 26-reside H4 histone tail. As a negative control, computed folding profile of a regular globular miniprotein (CLN025) in OPC water is in appreciably better agreement with experiment than that obtained in TIP3P, which tends to overstabilize the compact native state relative to the extended conformations. We employed Aβ42 peptide to investigate the possible influence of the solvent box size on simulation outcomes. We advocate a cautious approach for simulations of IDPs: we suggest that the solvent box size should be at least four times the radius of gyration of the random coil corresponding to the IDP. The computed free energy landscape of protein IN in OPC resembles a shallow "tub" - conformations with substantially different degrees of compactness that are within 2 kB T of each other. Conformations with very different secondary structure content coexist within 1 kB T of the global free energy minimum. States with higher free energy tend to have less secondary structure. Computed low helical content of the protein has virtually no correlation with its degree of compactness, which calls into question the possibility of using the helicity as a metric for assessing performance of water models for IDPs, when the helicity is low. Predicted radius of gyration ( R g) of H4 histone tail in OPC water falls in-between that of a typical globular protein and a fully denatured protein of the same size; the predicted R g is consistent with two independent predictions. In contrast, H4 tail in TIP3P water is as compact as the corresponding globular protein. The computed free energy landscape of H4 tail in OPC is relatively flat over a significant range of compactness, which, we argue, is consistent with its biological function as facilitator of internucleosome interactions.
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Affiliation(s)
| | - Saeed Izadi
- Early Stage Pharmaceutical Development , Genentech Inc. , South San Francisco , California 94080 , United States
| | - Alexey V Onufriev
- Department of Computer Science , Virginia Tech , Blacksburg , Virginia 24060 , United States.,Center for Soft Matter and Biological Physics , Virginia Tech , Blacksburg , Virginia 24061 , United States
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16
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Extreme Fuzziness: Direct Interactions between Two IDPs. Biomolecules 2019; 9:biom9030081. [PMID: 30813629 PMCID: PMC6468500 DOI: 10.3390/biom9030081] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Revised: 02/10/2019] [Accepted: 02/18/2019] [Indexed: 01/06/2023] Open
Abstract
Protein interactions involving intrinsically disordered proteins (IDPs) greatly extend the range of binding mechanisms available to proteins. In interactions employing coupled folding and binding, IDPs undergo disorder-to-order transitions to form a complex with a well-defined structure. In many other cases, IDPs retain structural plasticity in the final complexes, which have been defined as the fuzzy complexes. While a large number of fuzzy complexes have been characterized with variety of fuzzy patterns, many of the interactions are between an IDP and a structured protein. Thus, whether two IDPs can interact directly to form a fuzzy complex without disorder-to-order transition remains an open question. Recently, two studies of interactions between IDPs (4.1G-CTD/NuMA and H1/ProTα) have found a definite answer to this question. Detailed characterizations combined with nuclear magnetic resonance (NMR), single-molecule Förster resonance energy transfer (smFRET) and molecular dynamics (MD) simulation demonstrate that direct interactions between these two pairs of IDPs do form fuzzy complexes while retaining the conformational dynamics of the isolated proteins, which we name as the extremely fuzzy complexes. Extreme fuzziness completes the full spectrum of protein-protein interaction modes, suggesting that a more generalized model beyond existing binding mechanisms is required. Previous models of protein interaction could be applicable to some aspects of the extremely fuzzy interactions, but in more general sense, the distinction between native and nonnative contacts, which was used to understand protein folding and binding, becomes obscure. Exploring the phenomenon of extreme fuzziness may shed new light on molecular recognition and drug design.
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17
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Childers MC, Daggett V. Validating Molecular Dynamics Simulations against Experimental Observables in Light of Underlying Conformational Ensembles. J Phys Chem B 2018; 122:6673-6689. [PMID: 29864281 DOI: 10.1021/acs.jpcb.8b02144] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Far from the static, idealized conformations deposited into structural databases, proteins are highly dynamic molecules that undergo conformational changes on temporal and spatial scales that may span several orders of magnitude. These conformational changes, often intimately connected to the functional roles that proteins play, may be obscured by traditional biophysical techniques. Over the past 40 years, molecular dynamics (MD) simulations have complemented these techniques by providing the "hidden" atomistic details that underlie protein dynamics. However, there are limitations of the degree to which molecular simulations accurately and quantitatively describe protein motions. Here we show that although four molecular dynamics simulation packages (AMBER, GROMACS, NAMD, and ilmm) reproduced a variety of experimental observables for two different proteins (engrailed homeodomain and RNase H) equally well overall at room temperature, there were subtle differences in the underlying conformational distributions and the extent of conformational sampling obtained. This leads to ambiguity about which results are correct, as experiment cannot always provide the necessary detailed information to distinguish between the underlying conformational ensembles. However, the results with different packages diverged more when considering larger amplitude motion, for example, the thermal unfolding process and conformational states sampled, with some packages failing to allow the protein to unfold at high temperature or providing results at odds with experiment. While most differences between MD simulations performed with different packages are attributed to the force fields themselves, there are many other factors that influence the outcome, including the water model, algorithms that constrain motion, how atomic interactions are handled, and the simulation ensemble employed. Here four different MD packages were tested each using best practices as established by the developers, utilizing three different protein force fields and three different water models. Differences between the simulated protein behavior using two different packages but the same force field, as well as two different packages with different force fields but the same water models and approaches to restraining motion, show how other factors can influence the behavior, and it is incorrect to place all the blame for deviations and errors on force fields or to expect improvements in force fields alone to solve such problems.
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Affiliation(s)
- Matthew Carter Childers
- Department of Bioengineering , University of Washington , Seattle , Washington 98195-5013 , United States
| | - Valerie Daggett
- Department of Bioengineering , University of Washington , Seattle , Washington 98195-5013 , United States
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18
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Das P, Matysiak S, Mittal J. Looking at the Disordered Proteins through the Computational Microscope. ACS CENTRAL SCIENCE 2018; 4:534-542. [PMID: 29805999 PMCID: PMC5968442 DOI: 10.1021/acscentsci.7b00626] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Indexed: 05/04/2023]
Abstract
Intrinsically disordered proteins (IDPs) have attracted wide interest over the past decade due to their surprising prevalence in the proteome and versatile roles in cell physiology and pathology. A large selection of IDPs has been identified as potential targets for therapeutic intervention. Characterizing the structure-function relationship of disordered proteins is therefore an essential but daunting task, as these proteins can adapt transient structure, necessitating a new paradigm for connecting structural disorder to function. Molecular simulation has emerged as a natural complement to experiments for atomic-level characterizations and mechanistic investigations of this intriguing class of proteins. The diverse range of length and time scales involved in IDP function requires performing simulations at multiple levels of resolution. In this Outlook, we focus on summarizing available simulation methods, along with a few interesting example applications. We also provide an outlook on how these simulation methods can be further improved in order to provide a more accurate description of IDP structure, binding, and assembly.
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Affiliation(s)
- Payel Das
- IBM Thomas J.
Watson Research Center, Yorktown Heights, New York 10598, United States
- E-mail:
| | - Silvina Matysiak
- Fischell
Department of Bioengineering, University
of Maryland, College Park, Maryland 20742, United States
| | - Jeetain Mittal
- Department
of Chemical and Biomolecular Engineering, Lehigh University, Bethlehem, Pennsylvania 18015, United States
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19
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Bernetti M, Masetti M, Pietrucci F, Blackledge M, Jensen MR, Recanatini M, Mollica L, Cavalli A. Structural and Kinetic Characterization of the Intrinsically Disordered Protein SeV NTAIL through Enhanced Sampling Simulations. J Phys Chem B 2017; 121:9572-9582. [DOI: 10.1021/acs.jpcb.7b08925] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Mattia Bernetti
- Department
of Pharmacy and Biotechnology, Alma Mater Studiorum − Università di Bologna, Via Belmeloro 6, 40126, Bologna, Italy
- CompuNet, Istituto Italiano di Tecnologia, Via Morego 30, 16163, Genova, Italy
| | - Matteo Masetti
- Department
of Pharmacy and Biotechnology, Alma Mater Studiorum − Università di Bologna, Via Belmeloro 6, 40126, Bologna, Italy
| | - Fabio Pietrucci
- Institut
de Minéralogie,
de Physique des Matériaux et de Cosmochimie, Sorbonne Universités−Université
Pierre et Marie Curie Paris 6, CNRS UMR 7590, IRD UMR 206, Museum national d’Histoire naturelle, F-75005 Paris, France
| | - Martin Blackledge
- Protein
Dynamics and Flexibility by NMR Group, Institut de Biologie Structurale, 38044 Grenoble, France
| | - Malene Ringkjobing Jensen
- Protein
Dynamics and Flexibility by NMR Group, Institut de Biologie Structurale, 38044 Grenoble, France
| | - Maurizio Recanatini
- Department
of Pharmacy and Biotechnology, Alma Mater Studiorum − Università di Bologna, Via Belmeloro 6, 40126, Bologna, Italy
| | - Luca Mollica
- CompuNet, Istituto Italiano di Tecnologia, Via Morego 30, 16163, Genova, Italy
| | - Andrea Cavalli
- Department
of Pharmacy and Biotechnology, Alma Mater Studiorum − Università di Bologna, Via Belmeloro 6, 40126, Bologna, Italy
- CompuNet, Istituto Italiano di Tecnologia, Via Morego 30, 16163, Genova, Italy
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20
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Computational and theoretical advances in studies of intrinsically disordered proteins. Curr Opin Struct Biol 2017; 42:147-154. [PMID: 28259050 DOI: 10.1016/j.sbi.2017.01.006] [Citation(s) in RCA: 154] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 01/16/2017] [Accepted: 01/21/2017] [Indexed: 01/08/2023]
Abstract
Intrinsically disordered proteins (IDPs) are increasingly realized to play diverse biological roles, ranging from molecular signaling to the formation of membraneless organelles. Their high degree of disorder makes them more challenging to study using the techniques of conventional structural biology, because any observable will be averaged over a heterogeneous ensemble of structures. Molecular simulations and theory are therefore a natural complement to experiment for studying the structure, dynamics and function of IDPs. The diverse time and length scales relevant to the roles played by IDPs require flexibility in the techniques applied. Here, I summarize some of the developments in simulation and theory in recent years, which have been driven by the desire to better capture IDP properties at different time- and length-scales. I also provide an outlook for how methods can be improved in the future and emerging problems which may be addressed by theory and simulation.
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21
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Abstract
The investigation of intrinsically disordered proteins (IDPs) is a new frontier in structural and molecular biology that requires a new paradigm to connect structural disorder to function. Molecular dynamics simulations and statistical thermodynamics potentially offer ideal tools for atomic-level characterizations and thermodynamic descriptions of this fascinating class of proteins that will complement experimental studies. However, IDPs display sensitivity to inaccuracies in the underlying molecular mechanics force fields. Thus, achieving an accurate structural characterization of IDPs via simulations is a challenge. It is also daunting to perform a configuration-space integration over heterogeneous structural ensembles sampled by IDPs to extract, in particular, protein configurational entropy. In this review, we summarize recent efforts devoted to the development of force fields and the critical evaluations of their performance when applied to IDPs. We also survey recent advances in computational methods for protein configurational entropy that aim to provide a thermodynamic link between structural disorder and protein activity.
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Affiliation(s)
- Song-Ho Chong
- Department of Chemistry, Sookmyung Women's University, Yongsan-Ku, Seoul 04310, Korea;
| | - Prathit Chatterjee
- Department of Chemistry, Sookmyung Women's University, Yongsan-Ku, Seoul 04310, Korea;
| | - Sihyun Ham
- Department of Chemistry, Sookmyung Women's University, Yongsan-Ku, Seoul 04310, Korea;
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22
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Carballo‐Pacheco M, Strodel B. Comparison of force fields for Alzheimer's A β42: A case study for intrinsically disordered proteins. Protein Sci 2017; 26:174-185. [PMID: 27727496 PMCID: PMC5275744 DOI: 10.1002/pro.3064] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Revised: 10/02/2016] [Accepted: 10/09/2016] [Indexed: 01/06/2023]
Abstract
Intrinsically disordered proteins are essential for biological processes such as cell signalling, but are also associated to devastating diseases including Alzheimer's disease, Parkinson's disease or type II diabetes. Because of their lack of a stable three-dimensional structure, molecular dynamics simulations are often used to obtain atomistic details that cannot be observed experimentally. The applicability of molecular dynamics simulations depends on the accuracy of the force field chosen to represent the underlying free energy surface of the system. Here, we use replica exchange molecular dynamics simulations to test five modern force fields, OPLS, AMBER99SB, AMBER99SB*ILDN, AMBER99SBILDN-NMR and CHARMM22*, in their ability to model Aβ42 , an intrinsically disordered peptide associated with Alzheimer's disease, and compare our results to nuclear magnetic resonance (NMR) experimental data. We observe that all force fields except AMBER99SBILDN-NMR successfully reproduce local NMR observables, with CHARMM22* being slightly better than the other force fields.
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Affiliation(s)
- Martín Carballo‐Pacheco
- Institute of Complex Systems, Structural Biochemistry (ICS‐6), Forschungszentrum Jülich GmbHJülich52425Germany
- AICES Graduate School, RWTH Aachen UniversitySchinkelstraße 2Aachen52062Germany
| | - Birgit Strodel
- Institute of Complex Systems, Structural Biochemistry (ICS‐6), Forschungszentrum Jülich GmbHJülich52425Germany
- Institute of Theoretical and Computational Chemistry, Heinrich Heine University DüsseldorfUniversitätstraße 1Düsseldorf40225Germany
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23
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Gandhi NS, Kukic P, Lippens G, Mancera RL. Molecular Dynamics Simulation of Tau Peptides for the Investigation of Conformational Changes Induced by Specific Phosphorylation Patterns. Methods Mol Biol 2017; 1523:33-59. [PMID: 27975243 DOI: 10.1007/978-1-4939-6598-4_3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The Tau protein plays an important role due to its biomolecular interactions in neurodegenerative diseases. The lack of stable structure and various posttranslational modifications such as phosphorylation at various sites in the Tau protein pose a challenge for many experimental methods that are traditionally used to study protein folding and aggregation. Atomistic molecular dynamics (MD) simulations can help around deciphering relationship between phosphorylation and various intermediate and stable conformations of the Tau protein which occur on longer timescales. This chapter outlines protocols for the preparation, execution, and analysis of all-atom MD simulations of a 21-amino acid-long phosphorylated Tau peptide with the aim of generating biologically relevant structural and dynamic information. The simulations are done in explicit solvent and starting from nearly extended configurations of the peptide. The scaled MD method implemented in AMBER14 was chosen to achieve enhanced conformational sampling in addition to a conventional MD approach, thereby allowing the characterization of folding for such an intrinsically disordered peptide at 293 K. Emphasis is placed on the analysis of the simulation trajectories to establish correlations with NMR data (i.e., chemical shifts and NOEs). Finally, in-depth discussions are provided for commonly encountered problems.
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Affiliation(s)
- Neha S Gandhi
- School of Biomedical Sciences, CHIRI Biosciences and Curtin Institute for Computation, Curtin University, G.P.O. Box U1987, Perth, WA, 6845, Australia.
| | - Predrag Kukic
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
| | - Guy Lippens
- Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés, Université de Toulouse, CNRS, INRA, INSA Toulouse, 135Avenue de Rangueil, 31077, Toulouse, France
- Université de Lille, CNRS, UMR 8576, UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, 59000 Lille, France
| | - Ricardo L Mancera
- School of Biomedical Sciences, CHIRI Biosciences and Curtin Institute for Computation, Curtin University, G.P.O. Box U1987, Perth, WA, 6845, Australia.
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24
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Kukharenko O, Sawade K, Steuer J, Peter C. Using Dimensionality Reduction to Systematically Expand Conformational Sampling of Intrinsically Disordered Peptides. J Chem Theory Comput 2016; 12:4726-4734. [DOI: 10.1021/acs.jctc.6b00503] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
| | - Kevin Sawade
- Theoretical
Chemistry, University of Konstanz, 78547 Konstanz, Germany
| | - Jakob Steuer
- Theoretical
Chemistry, University of Konstanz, 78547 Konstanz, Germany
| | - Christine Peter
- Theoretical
Chemistry, University of Konstanz, 78547 Konstanz, Germany
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25
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Aznauryan M, Delgado L, Soranno A, Nettels D, Huang JR, Labhardt AM, Grzesiek S, Schuler B. Comprehensive structural and dynamical view of an unfolded protein from the combination of single-molecule FRET, NMR, and SAXS. Proc Natl Acad Sci U S A 2016; 113:E5389-98. [PMID: 27566405 PMCID: PMC5027429 DOI: 10.1073/pnas.1607193113] [Citation(s) in RCA: 110] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The properties of unfolded proteins are essential both for the mechanisms of protein folding and for the function of the large group of intrinsically disordered proteins. However, the detailed structural and dynamical characterization of these highly dynamic and conformationally heterogeneous ensembles has remained challenging. Here we combine and compare three of the leading techniques for the investigation of unfolded proteins, NMR spectroscopy (NMR), small-angle X-ray scattering (SAXS), and single-molecule Förster resonance energy transfer (FRET), with the goal of quantitatively testing their consistency and complementarity and for obtaining a comprehensive view of the unfolded-state ensemble. Using unfolded ubiquitin as a test case, we find that its average dimensions derived from FRET and from structural ensembles calculated using the program X-PLOR-NIH based on NMR and SAXS restraints agree remarkably well; even the shapes of the underlying intramolecular distance distributions are in good agreement, attesting to the reliability of the approaches. The NMR-based results provide a highly sensitive way of quantifying residual structure in the unfolded state. FRET-based nanosecond fluorescence correlation spectroscopy allows long-range distances and chain dynamics to be probed in a time range inaccessible by NMR. The combined techniques thus provide a way of optimally using the complementarity of the available methods for a quantitative structural and dynamical description of unfolded proteins both at the global and the local level.
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Affiliation(s)
- Mikayel Aznauryan
- Department of Biochemistry, University of Zurich, 8057 Zurich, Switzerland
| | | | - Andrea Soranno
- Department of Biochemistry, University of Zurich, 8057 Zurich, Switzerland
| | - Daniel Nettels
- Department of Biochemistry, University of Zurich, 8057 Zurich, Switzerland
| | - Jie-Rong Huang
- Institute of Biochemistry and Molecular Biology, National Yang Ming University, Taipei City 112, Taiwan
| | | | | | - Benjamin Schuler
- Department of Biochemistry, University of Zurich, 8057 Zurich, Switzerland; Department of Physics, University of Zurich, 8057 Zurich, Switzerland
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26
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Do TN, Choy WY, Karttunen M. Binding of Disordered Peptides to Kelch: Insights from Enhanced Sampling Simulations. J Chem Theory Comput 2015; 12:395-404. [PMID: 26636721 DOI: 10.1021/acs.jctc.5b00868] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Keap1 protein plays an essential role in regulating cellular oxidative stress response and is a crucial binding hub for multiple proteins, several of which are intrinsically disordered proteins (IDP). Among Kelch's IDP binding partners, NRF2 and PTMA are the two most interesting cases. They share a highly similar binding motif; however, NRF2 binds to Kelch with a binding affinity of approximately 100-fold higher than that of PTMA. In this study, we perform an exhaustive sampling composed of 6 μs well-tempered metadynamics and 2 μs unbiased molecular dynamics (MD) simulations aiming at characterizing the binding mechanisms and structural properties of these two peptides. Our results agree with previous experimental observations that PTMA is remarkably more disordered than NRF2 in both the free and bound states. This explains PTMA's lower binding affinity. Our extensive sampling also provides valuable insights into the vast conformational ensembles of both NRF2 and PTMA, supports the hypothesis of coupled folding-binding, and confirms the essential role of linear motifs in IDP binding.
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Affiliation(s)
- Trang Nhu Do
- Department of Chemistry and Waterloo Institute for Nanotechnology, University of Waterloo , 200 University Avenue West, Waterloo, ON, Canada N2L 3G1
| | - Wing-Yiu Choy
- Department of Biochemistry, University of Western Ontario , 1151 Richmond Street, London, ON, Canada N6A 3K7
| | - Mikko Karttunen
- Department of Mathematics and Computer Science & Institute for Complex Molecular Systems, Eindhoven University of Technology , P.O. Box 513, MetaForum, 5600 MB, Eindhoven, The Netherlands
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27
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Olsson S, Cavalli A. Quantification of Entropy-Loss in Replica-Averaged Modeling. J Chem Theory Comput 2015; 11:3973-7. [DOI: 10.1021/acs.jctc.5b00579] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Simon Olsson
- Institute for Research in Biomedicine, Via Vincenzo Vela 6, CH-6500 Bellinzona, Ticino, Switzerland
- Laboratory
of Physical Chemistry, Swiss Federal Institute of Technology, ETH-Hönggerberg, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Zürich, Switzerland
| | - Andrea Cavalli
- Institute for Research in Biomedicine, Via Vincenzo Vela 6, CH-6500 Bellinzona, Ticino, Switzerland
- Department
of Chemistry, University of Cambridge, Cambridge, CB2 1EW United Kingdom
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