1
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Ashraf HN, Uversky VN. Intrinsic Disorder in the Host Proteins Entrapped in Rabies Virus Particles. Viruses 2024; 16:916. [PMID: 38932209 PMCID: PMC11209445 DOI: 10.3390/v16060916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 05/23/2024] [Accepted: 05/28/2024] [Indexed: 06/28/2024] Open
Abstract
A proteomics analysis of purified rabies virus (RABV) revealed 47 entrapped host proteins within the viral particles. Out of these, 11 proteins were highly disordered. Our study was particularly focused on five of the RABV-entrapped mouse proteins with the highest levels of disorder: Neuromodulin, Chmp4b, DnaJB6, Vps37B, and Wasl. We extensively utilized bioinformatics tools, such as FuzDrop, D2P2, UniProt, RIDAO, STRING, AlphaFold, and ELM, for a comprehensive analysis of the intrinsic disorder propensity of these proteins. Our analysis suggested that these disordered host proteins might play a significant role in facilitating the rabies virus pathogenicity, immune system evasion, and the development of antiviral drug resistance. Our study highlighted the complex interaction of the virus with its host, with a focus on how the intrinsic disorder can play a crucial role in virus pathogenic processes, and suggested that these intrinsically disordered proteins (IDPs) and disorder-related host interactions can also be a potential target for therapeutic strategies.
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Affiliation(s)
- Hafiza Nimra Ashraf
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA;
| | - Vladimir N. Uversky
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA;
- USF Health Byrd Alzheimer’s Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA
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2
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Maiti S, Singh A, Maji T, Saibo NV, De S. Experimental methods to study the structure and dynamics of intrinsically disordered regions in proteins. Curr Res Struct Biol 2024; 7:100138. [PMID: 38707546 PMCID: PMC11068507 DOI: 10.1016/j.crstbi.2024.100138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 03/12/2024] [Accepted: 03/15/2024] [Indexed: 05/07/2024] Open
Abstract
Eukaryotic proteins often feature long stretches of amino acids that lack a well-defined three-dimensional structure and are referred to as intrinsically disordered proteins (IDPs) or regions (IDRs). Although these proteins challenge conventional structure-function paradigms, they play vital roles in cellular processes. Recent progress in experimental techniques, such as NMR spectroscopy, single molecule FRET, high speed AFM and SAXS, have provided valuable insights into the biophysical basis of IDP function. This review discusses the advancements made in these techniques particularly for the study of disordered regions in proteins. In NMR spectroscopy new strategies such as 13C detection, non-uniform sampling, segmental isotope labeling, and rapid data acquisition methods address the challenges posed by spectral overcrowding and low stability of IDPs. The importance of various NMR parameters, including chemical shifts, hydrogen exchange rates, and relaxation measurements, to reveal transient secondary structures within IDRs and IDPs are presented. Given the high flexibility of IDPs, the review outlines NMR methods for assessing their dynamics at both fast (ps-ns) and slow (μs-ms) timescales. IDPs exert their functions through interactions with other molecules such as proteins, DNA, or RNA. NMR-based titration experiments yield insights into the thermodynamics and kinetics of these interactions. Detailed study of IDPs requires multiple experimental techniques, and thus, several methods are described for studying disordered proteins, highlighting their respective advantages and limitations. The potential for integrating these complementary techniques, each offering unique perspectives, is explored to achieve a comprehensive understanding of IDPs.
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Affiliation(s)
| | - Aakanksha Singh
- School of Bioscience, Indian Institute of Technology Kharagpur, Kharagpur, WB, 721302, India
| | - Tanisha Maji
- School of Bioscience, Indian Institute of Technology Kharagpur, Kharagpur, WB, 721302, India
| | - Nikita V. Saibo
- School of Bioscience, Indian Institute of Technology Kharagpur, Kharagpur, WB, 721302, India
| | - Soumya De
- School of Bioscience, Indian Institute of Technology Kharagpur, Kharagpur, WB, 721302, India
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3
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Uversky VN. Functional unfoldomics: Roles of intrinsic disorder in protein (multi)functionality. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2023; 138:179-210. [PMID: 38220424 DOI: 10.1016/bs.apcsb.2023.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2024]
Abstract
Intrinsically disordered proteins (IDPs), which are functional proteins without stable tertiary structure, and hybrid proteins containing ordered domains and intrinsically disordered regions (IDRs) constitute prominent parts of all proteomes collectively known as unfoldomes. IDPs/IDRs exist as highly dynamic structural ensembles of rapidly interconverting conformations and are characterized by the exceptional structural heterogeneity, where their different parts are (dis)ordered to different degree, and their overall structure represents a complex mosaic of foldons, inducible foldons, inducible morphing foldons, non-foldons, semifoldons, and even unfoldons. Despite their lack of unique 3D structures, IDPs/IDRs play crucial roles in the control of various biological processes and the regulation of different cellular pathways and are commonly involved in recognition and signaling, indicating that the disorder-based functional repertoire is complementary to the functions of ordered proteins. Furthermore, IDPs/IDRs are frequently multifunctional, and this multifunctionality is defined by their structural flexibility and heterogeneity. Intrinsic disorder phenomenon is at the roots of the structure-function continuum model, where the structure continuum is defined by the presence of differently (dis)ordered regions, and the function continuum arises from the ability of all these differently (dis)ordered parts to have different functions. In their everyday life, IDPs/IDRs utilize a broad spectrum of interaction mechanisms thereby acting as interaction specialists. They are crucial for the biogenesis of numerous proteinaceous membrane-less organelles driven by the liquid-liquid phase separation. This review introduces functional unfoldomics by representing some aspects of the intrinsic disorder-based functionality.
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Affiliation(s)
- Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, United States.
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4
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Białobrzewski MK, Klepka BP, Michaś A, Cieplak-Rotowska MK, Staszałek Z, Niedźwiecka A. Diversity of hydrodynamic radii of intrinsically disordered proteins. EUROPEAN BIOPHYSICS JOURNAL : EBJ 2023; 52:607-618. [PMID: 37831084 PMCID: PMC10618399 DOI: 10.1007/s00249-023-01683-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 08/08/2023] [Accepted: 09/06/2023] [Indexed: 10/14/2023]
Abstract
Intrinsically disordered proteins (IDPs) form an important class of biomolecules regulating biological processes in higher organisms. The lack of a fixed spatial structure facilitates them to perform their regulatory functions and allows the efficiency of biochemical reactions to be controlled by temperature and the cellular environment. From the biophysical point of view, IDPs are biopolymers with a broad configuration state space and their actual conformation depends on non-covalent interactions of its amino acid side chain groups at given temperature and chemical conditions. Thus, the hydrodynamic radius (Rh) of an IDP of a given polymer length (N) is a sequence- and environment-dependent variable. We have reviewed the literature values of hydrodynamic radii of IDPs determined experimentally by SEC, AUC, PFG NMR, DLS, and FCS, and complement them with our FCS results obtained for a series of protein fragments involved in the regulation of human gene expression. The data collected herein show that the values of hydrodynamic radii of IDPs can span the full space between the folded globular and denatured proteins in the Rh(N) diagram.
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Affiliation(s)
- Michał K Białobrzewski
- Laboratory of Biological Physics, Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, PL-02668, Warsaw, Poland
| | - Barbara P Klepka
- Laboratory of Biological Physics, Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, PL-02668, Warsaw, Poland
| | - Agnieszka Michaś
- Laboratory of Biological Physics, Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, PL-02668, Warsaw, Poland
| | - Maja K Cieplak-Rotowska
- Laboratory of Biological Physics, Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, PL-02668, Warsaw, Poland
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Pasteura 5, PL-02093, Warsaw, Poland
- The International Institute of Molecular Mechanisms and Machines, Polish Academy of Sciences, Flisa 6, PL-02247, Warsaw, Poland
| | - Zuzanna Staszałek
- Laboratory of Biological Physics, Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, PL-02668, Warsaw, Poland
| | - Anna Niedźwiecka
- Laboratory of Biological Physics, Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, PL-02668, Warsaw, Poland.
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5
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Piersimoni L, Abd El Malek M, Bhatia T, Bender J, Brankatschk C, Calvo Sánchez J, Dayhoff GW, Di Ianni A, Figueroa Parra JO, Garcia-Martinez D, Hesselbarth J, Köppen J, Lauth LM, Lippik L, Machner L, Sachan S, Schmidt L, Selle R, Skalidis I, Sorokin O, Ubbiali D, Voigt B, Wedler A, Wei AAJ, Zorn P, Dunker AK, Köhn M, Sinz A, Uversky VN. Lighting up Nobel Prize-winning studies with protein intrinsic disorder. Cell Mol Life Sci 2022; 79:449. [PMID: 35882686 PMCID: PMC11072364 DOI: 10.1007/s00018-022-04468-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 06/18/2022] [Accepted: 07/04/2022] [Indexed: 11/03/2022]
Abstract
Intrinsically disordered proteins and regions (IDPs and IDRs) and their importance in biology are becoming increasingly recognized in biology, biochemistry, molecular biology and chemistry textbooks, as well as in current protein science and structural biology curricula. We argue that the sequence → dynamic conformational ensemble → function principle is of equal importance as the classical sequence → structure → function paradigm. To highlight this point, we describe the IDPs and/or IDRs behind the discoveries associated with 17 Nobel Prizes, 11 in Physiology or Medicine and 6 in Chemistry. The Nobel Laureates themselves did not always mention that the proteins underlying the phenomena investigated in their award-winning studies are in fact IDPs or contain IDRs. In several cases, IDP- or IDR-based molecular functions have been elucidated, while in other instances, it is recognized that the respective protein(s) contain IDRs, but the specific IDR-based molecular functions have yet to be determined. To highlight the importance of IDPs and IDRs as general principle in biology, we present here illustrative examples of IDPs/IDRs in Nobel Prize-winning mechanisms and processes.
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Affiliation(s)
- Lolita Piersimoni
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Marina Abd El Malek
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Twinkle Bhatia
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Julian Bender
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Christin Brankatschk
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Jaime Calvo Sánchez
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Guy W Dayhoff
- Department of Chemistry, College of Art and Sciences, University of South Florida, Tampa, FL, 33620, USA
| | - Alessio Di Ianni
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | | | - Dailen Garcia-Martinez
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Julia Hesselbarth
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Janett Köppen
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Luca M Lauth
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Laurin Lippik
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Lisa Machner
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Shubhra Sachan
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Lisa Schmidt
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Robin Selle
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Ioannis Skalidis
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Oleksandr Sorokin
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Daniele Ubbiali
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Bruno Voigt
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Alice Wedler
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Alan An Jung Wei
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Peter Zorn
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Alan Keith Dunker
- Department of Biochemistry and Molecular Biology, Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Marcel Köhn
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany.
| | - Andrea Sinz
- Research Training Group RTG2467, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany.
| | - Vladimir N Uversky
- Department of Molecular Medicine, USF Health Byrd Alzheimer's Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA.
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6
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Bychkova VE, Dolgikh DA, Balobanov VA, Finkelstein AV. The Molten Globule State of a Globular Protein in a Cell Is More or Less Frequent Case Rather than an Exception. Molecules 2022; 27:molecules27144361. [PMID: 35889244 PMCID: PMC9319461 DOI: 10.3390/molecules27144361] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 07/01/2022] [Accepted: 07/03/2022] [Indexed: 02/01/2023] Open
Abstract
Quite a long time ago, Oleg B. Ptitsyn put forward a hypothesis about the possible functional significance of the molten globule (MG) state for the functioning of proteins. MG is an intermediate between the unfolded and the native state of a protein. Its experimental detection and investigation in a cell are extremely difficult. In the last decades, intensive studies have demonstrated that the MG-like state of some globular proteins arises from either their modifications or interactions with protein partners or other cell components. This review summarizes such reports. In many cases, MG was evidenced to be functionally important. Thus, the MG state is quite common for functional cellular proteins. This supports Ptitsyn’s hypothesis that some globular proteins may switch between two active states, rigid (N) and soft (MG), to work in solution or interact with partners.
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Affiliation(s)
- Valentina E. Bychkova
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia; (V.E.B.); (A.V.F.)
| | - Dmitry A. Dolgikh
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117871 Moscow, Russia;
| | - Vitalii A. Balobanov
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia; (V.E.B.); (A.V.F.)
- Correspondence:
| | - Alexei V. Finkelstein
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia; (V.E.B.); (A.V.F.)
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7
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Antifeeva IA, Fonin AV, Fefilova AS, Stepanenko OV, Povarova OI, Silonov SA, Kuznetsova IM, Uversky VN, Turoverov KK. Liquid-liquid phase separation as an organizing principle of intracellular space: overview of the evolution of the cell compartmentalization concept. Cell Mol Life Sci 2022; 79:251. [PMID: 35445278 PMCID: PMC11073196 DOI: 10.1007/s00018-022-04276-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 03/24/2022] [Accepted: 03/27/2022] [Indexed: 12/14/2022]
Abstract
At the turn of the twenty-first century, fundamental changes took place in the understanding of the structure and function of proteins and then in the appreciation of the intracellular space organization. A rather mechanistic model of the organization of living matter, where the function of proteins is determined by their rigid globular structure, and the intracellular processes occur in rigidly determined compartments, was replaced by an idea that highly dynamic and multifunctional "soft matter" lies at the heart of all living things. According this "new view", the most important role in the spatio-temporal organization of the intracellular space is played by liquid-liquid phase transitions of biopolymers. These self-organizing cellular compartments are open dynamic systems existing at the edge of chaos. They are characterized by the exceptional structural and compositional dynamics, and their multicomponent nature and polyfunctionality provide means for the finely tuned regulation of various intracellular processes. Changes in the external conditions can cause a disruption of the biogenesis of these cellular bodies leading to the irreversible aggregation of their constituent proteins, followed by the transition to a gel-like state and the emergence of amyloid fibrils. This work represents a historical overview of changes in our understanding of the intracellular space compartmentalization. It also reflects methodological breakthroughs that led to a change in paradigms in this area of science and discusses modern ideas about the organization of the intracellular space. It is emphasized here that the membrane-less organelles have to combine a certain resistance to the changes in their environment and, at the same time, show high sensitivity to the external signals, which ensures the normal functioning of the cell.
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Affiliation(s)
- Iuliia A Antifeeva
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Av., 4, St. Petersburg, 194064, Russia
| | - Alexander V Fonin
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Av., 4, St. Petersburg, 194064, Russia
| | - Anna S Fefilova
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Av., 4, St. Petersburg, 194064, Russia
| | - Olesya V Stepanenko
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Av., 4, St. Petersburg, 194064, Russia
| | - Olga I Povarova
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Av., 4, St. Petersburg, 194064, Russia
| | - Sergey A Silonov
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Av., 4, St. Petersburg, 194064, Russia
| | - Irina M Kuznetsova
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Av., 4, St. Petersburg, 194064, Russia
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd. MDC07, Tampa, FL, 33612, USA.
| | - Konstantin K Turoverov
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Av., 4, St. Petersburg, 194064, Russia.
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8
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Kulkarni P, Bhattacharya S, Achuthan S, Behal A, Jolly MK, Kotnala S, Mohanty A, Rangarajan G, Salgia R, Uversky V. Intrinsically Disordered Proteins: Critical Components of the Wetware. Chem Rev 2022; 122:6614-6633. [PMID: 35170314 PMCID: PMC9250291 DOI: 10.1021/acs.chemrev.1c00848] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Despite the wealth of knowledge gained about intrinsically disordered proteins (IDPs) since their discovery, there are several aspects that remain unexplored and, hence, poorly understood. A living cell is a complex adaptive system that can be described as a wetware─a metaphor used to describe the cell as a computer comprising both hardware and software and attuned to logic gates─capable of "making" decisions. In this focused Review, we discuss how IDPs, as critical components of the wetware, influence cell-fate decisions by wiring protein interaction networks to keep them minimally frustrated. Because IDPs lie between order and chaos, we explore the possibility that they can be modeled as attractors. Further, we discuss how the conformational dynamics of IDPs manifests itself as conformational noise, which can potentially amplify transcriptional noise to stochastically switch cellular phenotypes. Finally, we explore the potential role of IDPs in prebiotic evolution, in forming proteinaceous membrane-less organelles, in the origin of multicellularity, and in protein conformation-based transgenerational inheritance of acquired characteristics. Together, these ideas provide a new conceptual framework to discern how IDPs may perform critical biological functions despite their lack of structure.
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Affiliation(s)
- Prakash Kulkarni
- Department of Medical Oncology and Therapeutics Research, City of Hope National Medical Center, Duarte, CA, USA
- Address for correspondence: Prakash Kulkarni, Department of Medical Oncology and Therapeutics Research, City of Hope National Medical Center, Duarte, CA 91010, , Vladimir N. Uversky, Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida 33612,
| | - Supriyo Bhattacharya
- Integrative Genomics Core, City of Hope National Medical Center, Duarte, CA, USA
| | - Srisairam Achuthan
- Division of Research Informatics, Center for Informatics, City of Hope National Medical Center, Duarte, CA 91010, USA
| | - Amita Behal
- Department of Medical Oncology and Therapeutics Research, City of Hope National Medical Center, Duarte, CA, USA
| | - Mohit Kumar Jolly
- Center for BioSystems Science and Engineering, Indian Institute of Science, Bangalore 560012, India
| | - Sourabh Kotnala
- Department of Medical Oncology and Therapeutics Research, City of Hope National Medical Center, Duarte, CA, USA
| | - Atish Mohanty
- Department of Medical Oncology and Therapeutics Research, City of Hope National Medical Center, Duarte, CA, USA
| | - Govindan Rangarajan
- Department of Mathematics, Indian Institute of Science, Bangalore 560012, India
- Center for Neuroscience, Indian Institute of Science, Bangalore 560012, India
| | - Ravi Salgia
- Department of Medical Oncology and Therapeutics Research, City of Hope National Medical Center, Duarte, CA, USA
| | - Vladimir Uversky
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
- Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Institutskiy pereulok, 9, Dolgoprudny, Moscow region 141700, Russia
- Address for correspondence: Prakash Kulkarni, Department of Medical Oncology and Therapeutics Research, City of Hope National Medical Center, Duarte, CA 91010, , Vladimir N. Uversky, Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida 33612,
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9
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Kulkarni P, Leite VBP, Roy S, Bhattacharyya S, Mohanty A, Achuthan S, Singh D, Appadurai R, Rangarajan G, Weninger K, Orban J, Srivastava A, Jolly MK, Onuchic JN, Uversky VN, Salgia R. Intrinsically disordered proteins: Ensembles at the limits of Anfinsen's dogma. BIOPHYSICS REVIEWS 2022; 3:011306. [PMID: 38505224 PMCID: PMC10903413 DOI: 10.1063/5.0080512] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 02/17/2022] [Indexed: 03/21/2024]
Abstract
Intrinsically disordered proteins (IDPs) are proteins that lack rigid 3D structure. Hence, they are often misconceived to present a challenge to Anfinsen's dogma. However, IDPs exist as ensembles that sample a quasi-continuum of rapidly interconverting conformations and, as such, may represent proteins at the extreme limit of the Anfinsen postulate. IDPs play important biological roles and are key components of the cellular protein interaction network (PIN). Many IDPs can interconvert between disordered and ordered states as they bind to appropriate partners. Conformational dynamics of IDPs contribute to conformational noise in the cell. Thus, the dysregulation of IDPs contributes to increased noise and "promiscuous" interactions. This leads to PIN rewiring to output an appropriate response underscoring the critical role of IDPs in cellular decision making. Nonetheless, IDPs are not easily tractable experimentally. Furthermore, in the absence of a reference conformation, discerning the energy landscape representation of the weakly funneled IDPs in terms of reaction coordinates is challenging. To understand conformational dynamics in real time and decipher how IDPs recognize multiple binding partners with high specificity, several sophisticated knowledge-based and physics-based in silico sampling techniques have been developed. Here, using specific examples, we highlight recent advances in energy landscape visualization and molecular dynamics simulations to discern conformational dynamics and discuss how the conformational preferences of IDPs modulate their function, especially in phenotypic switching. Finally, we discuss recent progress in identifying small molecules targeting IDPs underscoring the potential therapeutic value of IDPs. Understanding structure and function of IDPs can not only provide new insight on cellular decision making but may also help to refine and extend Anfinsen's structure/function paradigm.
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Affiliation(s)
- Prakash Kulkarni
- Department of Medical Oncology and Therapeutics Research, City of Hope National Medical Center, Duarte, California 91010, USA
| | - Vitor B. P. Leite
- Departamento de Física, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista (UNESP), São José do Rio Preto, São Paulo 15054-000, Brazil
| | - Susmita Roy
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal 741246, India
| | - Supriyo Bhattacharyya
- Translational Bioinformatics, Center for Informatics, Department of Computational and Quantitative Medicine, City of Hope National Medical Center, Duarte, California 91010, USA
| | - Atish Mohanty
- Department of Medical Oncology and Therapeutics Research, City of Hope National Medical Center, Duarte, California 91010, USA
| | - Srisairam Achuthan
- Center for Informatics, Division of Research Informatics, City of Hope National Medical Center, Duarte, California 91010, USA
| | - Divyoj Singh
- Center for BioSystems Science and Engineering, Indian Institute of Science, Bangalore 560012, India
| | - Rajeswari Appadurai
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, Karnataka, India
| | - Govindan Rangarajan
- Department of Mathematics, Indian Institute of Science, Bangalore 560012, India
| | - Keith Weninger
- Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, USA
| | | | - Anand Srivastava
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, Karnataka, India
| | - Mohit Kumar Jolly
- Center for BioSystems Science and Engineering, Indian Institute of Science, Bangalore 560012, India
| | - Jose N. Onuchic
- Center for Theoretical Biological Physics, Rice University, Houston, Texas 77005-1892, USA
| | | | - Ravi Salgia
- Department of Medical Oncology and Therapeutics Research, City of Hope National Medical Center, Duarte, California 91010, USA
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10
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Bondos SE, Dunker AK, Uversky VN. Intrinsically disordered proteins play diverse roles in cell signaling. Cell Commun Signal 2022; 20:20. [PMID: 35177069 PMCID: PMC8851865 DOI: 10.1186/s12964-022-00821-7] [Citation(s) in RCA: 56] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 12/11/2021] [Indexed: 11/29/2022] Open
Abstract
Abstract Signaling pathways allow cells to detect and respond to a wide variety of chemical (e.g. Ca2+ or chemokine proteins) and physical stimuli (e.g., sheer stress, light). Together, these pathways form an extensive communication network that regulates basic cell activities and coordinates the function of multiple cells or tissues. The process of cell signaling imposes many demands on the proteins that comprise these pathways, including the abilities to form active and inactive states, and to engage in multiple protein interactions. Furthermore, successful signaling often requires amplifying the signal, regulating or tuning the response to the signal, combining information sourced from multiple pathways, all while ensuring fidelity of the process. This sensitivity, adaptability, and tunability are possible, in part, due to the inclusion of intrinsically disordered regions in many proteins involved in cell signaling. The goal of this collection is to highlight the many roles of intrinsic disorder in cell signaling. Following an overview of resources that can be used to study intrinsically disordered proteins, this review highlights the critical role of intrinsically disordered proteins for signaling in widely diverse organisms (animals, plants, bacteria, fungi), in every category of cell signaling pathway (autocrine, juxtacrine, intracrine, paracrine, and endocrine) and at each stage (ligand, receptor, transducer, effector, terminator) in the cell signaling process. Thus, a cell signaling pathway cannot be fully described without understanding how intrinsically disordered protein regions contribute to its function. The ubiquitous presence of intrinsic disorder in different stages of diverse cell signaling pathways suggest that more mechanisms by which disorder modulates intra- and inter-cell signals remain to be discovered. Graphical abstract ![]()
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Affiliation(s)
- Sarah E Bondos
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX, 77843, USA.
| | - A Keith Dunker
- Center for Computational Biology and Bioinformatics, Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA.,Institute for Biological Instrumentation of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", Pushchino, Moscow Region, Russia, 142290
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11
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Alghamdi M, Alamry SA, Bahlas SM, Uversky VN, Redwan EM. Circulating extracellular vesicles and rheumatoid arthritis: a proteomic analysis. Cell Mol Life Sci 2021; 79:25. [PMID: 34971426 PMCID: PMC11072894 DOI: 10.1007/s00018-021-04020-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 10/28/2021] [Accepted: 10/29/2021] [Indexed: 12/14/2022]
Abstract
Circulating extracellular vesicles (EVs) are membrane-bound nanoparticles secreted by most cells for intracellular communication and transportation of biomolecules. EVs carry proteins, lipids, nucleic acids, and receptors that are involved in human physiology and pathology. EV cargo is variable and highly related to the type and state of the cellular origin. Three subtypes of EVs have been identified: exosomes, microvesicles, and apoptotic bodies. Exosomes are the smallest and the most well-studied class of EVs that regulate different biological processes and participate in several diseases, such as cancers and autoimmune diseases. Proteomic analysis of exosomes succeeded in profiling numerous types of proteins involved in disease development and prognosis. In rheumatoid arthritis (RA), exosomes revealed a potential function in joint inflammation. These EVs possess a unique function, as they can transfer specific autoantigens and mediators between distant cells. Current proteomic data demonstrated that exosomes could provide beneficial effects against autoimmunity and exert an immunosuppressive action, particularly in RA. Based on these observations, effective therapeutic strategies have been developed for arthritis and other inflammatory disorders.
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Affiliation(s)
- Mohammed Alghamdi
- Biological Sciences Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah, 21589, Saudi Arabia
- Laboratory Department, University Medical Services Center, King Abdulaziz University, P.O. Box 80200, Jeddah, 21589, Saudi Arabia
| | - Sultan Abdulmughni Alamry
- Immunology Diagnostic Laboratory Department, King Abdulaziz University Hospital, P.O Box 80215, Jeddah, 21589, Saudi Arabia
| | - Sami M Bahlas
- Department of Internal Medicine, Faculty of Medicine, King Abdulaziz University, P.O. Box 80215, Jeddah, 21589, Saudi Arabia
| | - Vladimir N Uversky
- Biological Sciences Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah, 21589, Saudi Arabia
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| | - Elrashdy M Redwan
- Biological Sciences Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah, 21589, Saudi Arabia.
- Therapeutic and Protective Proteins Laboratory, Protein Research Department, Genetic Engineering and Biotechnology Research Institute, City for Scientific Research and Technology Applications, New Borg EL-Arab, 21934, Alexandria, Egypt.
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12
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Paiz EA, Allen JH, Correia JJ, Fitzkee NC, Hough LE, Whitten ST. Beta turn propensity and a model polymer scaling exponent identify intrinsically disordered phase-separating proteins. J Biol Chem 2021; 297:101343. [PMID: 34710373 PMCID: PMC8592878 DOI: 10.1016/j.jbc.2021.101343] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 10/19/2021] [Accepted: 10/20/2021] [Indexed: 12/14/2022] Open
Abstract
The complex cellular milieu can spontaneously demix, or phase separate, in a process controlled in part by intrinsically disordered (ID) proteins. A protein's propensity to phase separate is thought to be driven by a preference for protein-protein over protein-solvent interactions. The hydrodynamic size of monomeric proteins, as quantified by the polymer scaling exponent (v), is driven by a similar balance. We hypothesized that mean v, as predicted by protein sequence, would be smaller for proteins with a strong propensity to phase separate. To test this hypothesis, we analyzed protein databases containing subsets of proteins that are folded, disordered, or disordered and known to spontaneously phase separate. We find that the phase-separating disordered proteins, on average, had lower calculated values of v compared with their non-phase-separating counterparts. Moreover, these proteins had a higher sequence-predicted propensity for β-turns. Using a simple, surface area-based model, we propose a physical mechanism for this difference: transient β-turn structures reduce the desolvation penalty of forming a protein-rich phase and increase exposure of atoms involved in π/sp2 valence electron interactions. By this mechanism, β-turns could act as energetically favored nucleation points, which may explain the increased propensity for turns in ID regions (IDRs) utilized biologically for phase separation. Phase-separating IDRs, non-phase-separating IDRs, and folded regions could be distinguished by combining v and β-turn propensity. Finally, we propose a new algorithm, ParSe (partition sequence), for predicting phase-separating protein regions, and which is able to accurately identify folded, disordered, and phase-separating protein regions based on the primary sequence.
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Affiliation(s)
- Elisia A Paiz
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, Texas, USA
| | - Jeffre H Allen
- Department of Biochemistry, University of Colorado Boulder, Boulder, Colorado, USA
| | - John J Correia
- Department of Cell and Molecular Biology, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Nicholas C Fitzkee
- Department of Chemistry, Mississippi State University, Mississippi State, Mississippi, USA
| | - Loren E Hough
- Department of Physics, University of Colorado Boulder, Boulder, Colorado, USA; BioFrontiers Institute, University of Colorado Boulder, Boulder, Colorado, USA.
| | - Steven T Whitten
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, Texas, USA.
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13
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Hibino E, Hoshino M. A novel mode of interaction between intrinsically disordered proteins. Biophys Physicobiol 2020; 17:86-93. [PMID: 33194509 PMCID: PMC7610059 DOI: 10.2142/biophysico.bsj-2020012] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 06/29/2020] [Indexed: 01/22/2023] Open
Abstract
An increasing number of proteins, which have neither regular secondary nor well-defined tertiary structures, have been found to be present in cells. The structure of these proteins is highly flexible and disordered under physiological (native) conditions, and they are called “intrinsically disordered” proteins (IDPs). Many of the IDPs are involved in interactions with other biomolecules such as DNA, RNA, carbohydrates, and proteins. While these IDPs are largely unstructured by themselves, marked conformational changes often occur upon binding to an interacting partner, which is known as the “coupled folding and binding mechanism”, which enable them to change the conformation to become compatible with the shape of the multiple target biomolecules. We have studied the structure and interaction of eukaryotic transcription factors Sp1 and TAF4, and found that both of them have long intrinsically disordered regions (IDRs). One of the IDRs in Sp1 exhibited homo-oligomer formation. In addition, the same region was used for the interaction with another IDR found in the TAF4 molecule. In both cases, we have not detected any significant conformational change in that region, suggesting a prominent and novel binding mode for IDPs/IDRs, which are not categorized by the well-accepted concept of the coupled folding and binding mechanism.
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Affiliation(s)
- Emi Hibino
- Graduate School of Pharmaceutical Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Masaru Hoshino
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan
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14
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Kolonko M, Bystranowska D, Taube M, Kozak M, Bostock M, Popowicz G, Ożyhar A, Greb-Markiewicz B. The intrinsically disordered region of GCE protein adopts a more fixed structure by interacting with the LBD of the nuclear receptor FTZ-F1. Cell Commun Signal 2020; 18:180. [PMID: 33153474 PMCID: PMC7643343 DOI: 10.1186/s12964-020-00662-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 09/10/2020] [Indexed: 12/15/2022] Open
Abstract
The Drosophila melanogaster Germ cell-expressed protein (GCE) is a paralog of the juvenile hormone (JH) receptor - Methoprene tolerant protein (MET). Both proteins mediate JH function, preventing precocious differentiation during D. melanogaster development. Despite that GCE and MET are often referred to as equivalent JH receptors, their functions are not fully redundant and show tissue specificity. Both proteins belong to the family of bHLH-PAS transcription factors. The similarity of their primary structure is limited to defined bHLH and PAS domains, while their long C-terminal fragments (GCEC, METC) show significant differences and are expected to determine differences in GCE and MET protein activities. In this paper we present the structural characterization of GCEC as a coil-like intrinsically disordered protein (IDP) with highly elongated and asymmetric conformation. In comparison to previously characterized METC, GCEC is less compacted, contains more molecular recognition elements (MoREs) and exhibits a higher propensity for induced folding. The NMR shifts perturbation experiment and pull-down assay clearly demonstrated that the GCEC fragment is sufficient to form an interaction interface with the ligand binding domain (LBD) of the nuclear receptor Fushi Tarazu factor-1 (FTZ-F1). Significantly, these interactions can force GCEC to adopt more fixed structure that can modulate the activity, structure and functions of the full-length receptor. The discussed relation of protein functionality with the structural data of inherently disordered GCEC fragment is a novel look at this protein and contributes to a better understanding of the molecular basis of the functions of the C-terminal fragments of the bHLH-PAS family. Video abstract.
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Affiliation(s)
- Marta Kolonko
- Department of Biochemistry, Molecular Biology and Biotechnology, Faculty of Chemistry,
- Wroclaw University of Science and Technology
- , Wybrzeze Wyspianskiego 27, 50-370, Wroclaw, Poland.
| | - Dominika Bystranowska
- Department of Biochemistry, Molecular Biology and Biotechnology, Faculty of Chemistry,
- Wroclaw University of Science and Technology
- , Wybrzeze Wyspianskiego 27, 50-370, Wroclaw, Poland
| | - Michał Taube
- Department of Macromolecular Physics, Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznanskiego 2, 61-614, Poznan, Poland
| | - Maciej Kozak
- Department of Macromolecular Physics, Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznanskiego 2, 61-614, Poznan, Poland.,National Synchrotron Radiation Centre SOLARIS, Jagiellonian University, Czerwone Maki 98, 30-392, Krakow, Poland
| | - Mark Bostock
- Biomolecular NMR and Center for Integrated Protein Science Munich at Department Chemie, Technical University of Munich, Lichtenbergstraße 4, 85748, Garching, Germany.,Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764, Oberschleißheim, Germany
| | - Grzegorz Popowicz
- Biomolecular NMR and Center for Integrated Protein Science Munich at Department Chemie, Technical University of Munich, Lichtenbergstraße 4, 85748, Garching, Germany.,Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764, Oberschleißheim, Germany
| | - Andrzej Ożyhar
- Department of Biochemistry, Molecular Biology and Biotechnology, Faculty of Chemistry,
- Wroclaw University of Science and Technology
- , Wybrzeze Wyspianskiego 27, 50-370, Wroclaw, Poland
| | - Beata Greb-Markiewicz
- Department of Biochemistry, Molecular Biology and Biotechnology, Faculty of Chemistry,
- Wroclaw University of Science and Technology
- , Wybrzeze Wyspianskiego 27, 50-370, Wroclaw, Poland.
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15
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Elrashdy F, Redwan EM, Uversky VN. Intrinsic disorder perspective of an interplay between the renin-angiotensin-aldosterone system and SARS-CoV-2. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2020; 85:104510. [PMID: 32853823 PMCID: PMC7444473 DOI: 10.1016/j.meegid.2020.104510] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 08/15/2020] [Accepted: 08/19/2020] [Indexed: 02/07/2023]
Abstract
The novel severe acute respiratory syndrome (SARS) coronavirus SARS-CoV-2 walks the planet causing the rapid spread of the CoV disease 2019 (COVID-19) that has especially deleterious consequences for the patients with underlying cardiovascular diseases (CVDs). Entry of the SARS-CoV-2 into the host cell involves interaction of the virus (via the receptor-binding domain (RBD) of its spike glycoprotein) with the membrane-bound form of angiotensin-converting enzyme 2 (ACE2) followed by the virus-ACE2 complex internalization by the cell. Since ACE2 is expressed in various tissues, such as brain, gut, heart, kidney, and lung, and since these organs represent obvious targets for the SARS-CoV-2 infection, therapeutic approaches were developed to either inhibit ACE2 or reduce its expression as a means of prevention of the virus entry into the corresponding host cells. The problem here is that in addition to be a receptor for the SARS-CoV-2 entry into the host cells, ACE2 acts as a key component of the renin-angiotensin-aldosterone system (RAAS) aimed at the generation of a cascade of vasoactive peptides coordinating several physiological processes. In RAAS, ACE2 degrades angiotensin II, which is a multifunctional CVD-promoting peptide hormone and converts it to a heptapeptide angiotensin-(1-7) acting as the angiotensin II antagonist. As protein multifunctionality is commonly associated with the presence of flexible or disordered regions, we analyze here the intrinsic disorder predisposition of major players related to the SARS-CoV-2 - RAAS axis. We show that all considered proteins contain intrinsically disordered regions that might have specific functions. Since intrinsic disorder might play a role in the functionality of query proteins and be related to the COVID-19 pathogenesis, this work represents an important disorder-based outlook of an interplay between the renin-angiotensin-aldosterone system and SARS-CoV-2. It also suggests that consideration of the intrinsic disorder phenomenon should be added to the modern arsenal of means for drug development.
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Affiliation(s)
- Fatma Elrashdy
- Department of Endemic Medicine and Hepatogastroenterology, Kasr Alainy School of Medicine, Cairo University, Cairo, Egypt
| | - Elrashdy M Redwan
- Biological Science Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
| | - Vladimir N Uversky
- Biological Science Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia; Institute for Biological Instrumentation of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", Pushchino, Moscow region 142290, Russia; Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Bruce B. Downs Blvd., MDC07, Tampa, FL 33612, USA.
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16
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Páez-Pérez E, Llamas-García ML, Benítez-Cardoza CG, Montero-Morán GM, Lara-González S. Bioinformatic Analysis and Biophysical Characterization Reveal Structural Disorder in G0S2 Protein. ACS OMEGA 2020; 5:25841-25847. [PMID: 33073109 PMCID: PMC7557935 DOI: 10.1021/acsomega.0c03171] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 09/23/2020] [Indexed: 06/11/2023]
Abstract
G0S2 is a small protein of 103 residues in length that is involved in multiple cellular processes. To date, several reports have shown that G0S2 functions by making direct protein-protein interactions with key proteins. In lipolysis, G0S2 specifically interacts with adipose triglyceride lipase, inhibiting its activity and resulting in lipolysis being downregulated. In a similar way, G0S2 also participates in the regulation of apoptosis, cell proliferation, and oxidative phosphorylation; however, information regarding G0S2 structural and biophysical properties is limited. In this work, we conducted a comparative structural analysis of human and mouse G0S2 proteins. Bioinformatics suggests the presence of a disordered C-terminal region in human G0S2. Experimental characterization by size-exclusion chromatography and dynamic light scattering showed that human and mouse G0S2 have different hydrodynamic properties. In comparison to the mouse G0S2, which behaves similar to a globular protein, the human G0S2 shows an elongated conformation, most likely by displaying a disordered C-terminal region. Further analysis of hydrodynamic properties under denaturing conditions suggests the presence of a structural element in the mouse protein that undergoes an order to disorder transition at low urea concentration. Structural analysis by circular dichroism revealed that in native conditions, both proteins are mainly unstructured, showing the presence of beta sheet structures. Further analysis of CD data suggests that both proteins belong to the premolten globule family of intrinsically disordered proteins. We suggest that the intrinsic disorder observed in the G0S2 protein may facilitate its interaction with multiple partners in the regulation of cellular metabolism.
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Affiliation(s)
- Edgar
D. Páez-Pérez
- IPICYT,
División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica
A. C., San Luis Potosí 78216, México
| | - Miriam Livier Llamas-García
- IPICYT,
División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica
A. C., San Luis Potosí 78216, México
| | - Claudia G. Benítez-Cardoza
- Laboratorio
de Investigación Bioquímica, Programa Institucional
en Biomedicina Molecular ENMyH-Instituto Politécnico Nacional, Ciudad de México 07320, México
| | - Gabriela M. Montero-Morán
- Facultad
de Ciencias Químicas, Laboratorio IBCM, Universidad Autónoma de San Luis Potosí, San Luis Potosí 78210, México
| | - Samuel Lara-González
- IPICYT,
División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica
A. C., San Luis Potosí 78216, México
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17
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Van Bibber NW, Haerle C, Khalife R, Dayhoff GW, Uversky VN. Intrinsic Disorder in Human Proteins Encoded by Core Duplicon Gene Families. J Phys Chem B 2020; 124:8050-8070. [PMID: 32880174 DOI: 10.1021/acs.jpcb.0c07676] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Segmental duplications (i.e., highly homologous DNA fragments greater than 1 kb in length that are present within a genome at more than one site) are typically found in genome regions that are prone to rearrangements. A noticeable fraction of the human genome (∼5%) includes segmental duplications (or duplicons) that are assumed to play a number of vital roles in human evolution, human-specific adaptation, and genomic instability. Despite their importance for crucial events such as synaptogenesis, neuronal migration, and neocortical expansion, these segmental duplications continue to be rather poorly characterized. Of particular interest are the core duplicon gene (CDG) families, which are replicates sharing common "core" DNA among the randomly attached pieces and which expand along single chromosomes and might harbor newly acquired protein domains. Another important feature of proteins encoded by CDG families is their multifunctionality. Although it seems that these proteins might possess many characteristic features of intrinsically disordered proteins, to the best of our knowledge, a systematic investigation of the intrinsic disorder predisposition of the proteins encoded by core duplicon gene families has not been conducted yet. To fill this gap and to determine the degree to which these proteins might be affected by intrinsic disorder, we analyzed a set of human proteins encoded by the members of 10 core duplicon gene families, such as NBPF, RGPD, GUSBP, PMS2P, SPATA31, TRIM51, GOLGA8, NPIP, TBC1D3, and LRRC37. Our analysis revealed that the vast majority of these proteins are highly disordered, with their disordered regions often being utilized as means for the protein-protein interactions and/or targeted for numerous posttranslational modifications of different nature.
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Affiliation(s)
- Nathan W Van Bibber
- Department of Molecular Medicine Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Boulevard, Tampa, Florida 33612, United States
| | - Cornelia Haerle
- Department of Molecular Medicine Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Boulevard, Tampa, Florida 33612, United States
| | - Roy Khalife
- Department of Molecular Medicine Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Boulevard, Tampa, Florida 33612, United States
| | - Guy W Dayhoff
- Department of Chemistry, College of Art and Sciences, University of South Florida, Tampa, Florida 33620, United States
| | - Vladimir N Uversky
- Department of Molecular Medicine Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Boulevard, Tampa, Florida 33612, United States.,USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Boulevard, Tampa, Florida 33612, United States.,Institute for Biological Instrumentation, Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", 4 Institutskaya St., Pushchino, 142290, Moscow Region, Russia
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18
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Intrinsic Disorder in Tetratricopeptide Repeat Proteins. Int J Mol Sci 2020; 21:ijms21103709. [PMID: 32466138 PMCID: PMC7279152 DOI: 10.3390/ijms21103709] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 05/12/2020] [Accepted: 05/22/2020] [Indexed: 12/27/2022] Open
Abstract
Among the realm of repeat containing proteins that commonly serve as “scaffolds” promoting protein-protein interactions, there is a family of proteins containing between 2 and 20 tetratricopeptide repeats (TPRs), which are functional motifs consisting of 34 amino acids. The most distinguishing feature of TPR domains is their ability to stack continuously one upon the other, with these stacked repeats being able to affect interaction with binding partners either sequentially or in combination. It is known that many repeat-containing proteins are characterized by high levels of intrinsic disorder, and that many protein tandem repeats can be intrinsically disordered. Furthermore, it seems that TPR-containing proteins share many characteristics with hybrid proteins containing ordered domains and intrinsically disordered protein regions. However, there has not been a systematic analysis of the intrinsic disorder status of TPR proteins. To fill this gap, we analyzed 166 human TPR proteins to determine the degree to which proteins containing TPR motifs are affected by intrinsic disorder. Our analysis revealed that these proteins are characterized by different levels of intrinsic disorder and contain functional disordered regions that are utilized for protein-protein interactions and often serve as targets of various posttranslational modifications.
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19
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Abstract
Intrinsically disordered proteins (IDPs) can adopt a range of conformations from globules to swollen coils. This large range of conformational preferences for different IDPs raises the question of how conformational preferences are encoded by sequence. Global compositional features of a sequence such as the fraction of charged residues and the net charge per residue engender certain conformational biases. However, more specific sequence features such as the patterning of oppositely charged residues, expansion driving residues, or residues that can undergo posttranslational modifications can also influence the conformational ensembles of an IDP. Here, we outline how to calculate important global compositional features and patterning metrics that can be used to classify IDPs into different conformational classes and predict relative changes in conformation for sequences with the same amino acid composition. Although increased effort has been devoted to determining conformational properties of IDPs in recent years, quantitative predictions of conformation directly from sequence remain difficult and often inaccurate. Thus, if quantitative predictions of conformational properties are desired, then sequence-specific simulations must be performed.
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Affiliation(s)
- Kiersten M Ruff
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, USA.
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20
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Schramm A, Bignon C, Brocca S, Grandori R, Santambrogio C, Longhi S. An arsenal of methods for the experimental characterization of intrinsically disordered proteins - How to choose and combine them? Arch Biochem Biophys 2019; 676:108055. [PMID: 31356778 DOI: 10.1016/j.abb.2019.07.020] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 07/16/2019] [Accepted: 07/24/2019] [Indexed: 12/12/2022]
Abstract
In this review, we detail the most common experimental approaches to assess and characterize protein intrinsic structural disorder, with the notable exception of NMR and EPR spectroscopy, two ideally suited approaches that will be described in depth in two other reviews within this special issue. We discuss the advantages, the limitations, as well as the caveats of the various methods. We also describe less common and more demanding approaches that enable achieving further insights into the conformational properties of IDPs. Finally, we present recent developments that have enabled assessment of structural disorder in living cells, and discuss the currently available methods to model IDPs as conformational ensembles.
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Affiliation(s)
- Antoine Schramm
- CNRS and Aix-Marseille Univ, Laboratoire Architecture et Fonction des Macromolecules Biologiques (AFMB), UMR 7257, Marseille, France
| | - Christophe Bignon
- CNRS and Aix-Marseille Univ, Laboratoire Architecture et Fonction des Macromolecules Biologiques (AFMB), UMR 7257, Marseille, France
| | - Stefania Brocca
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
| | - Rita Grandori
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
| | - Carlo Santambrogio
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
| | - Sonia Longhi
- CNRS and Aix-Marseille Univ, Laboratoire Architecture et Fonction des Macromolecules Biologiques (AFMB), UMR 7257, Marseille, France.
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21
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Kulkarni V, Kulkarni P. Intrinsically disordered proteins and phenotypic switching: Implications in cancer. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2019; 166:63-84. [PMID: 31521237 DOI: 10.1016/bs.pmbts.2019.03.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
It is now well established that intrinsically disordered proteins (IDPs) that constitute a large part of the proteome across the three kingdoms, play critical roles in several biological processes including phenotypic switching. However, dysregulated expression of IDPs that engage in promiscuous interactions can lead to pathological states. In this chapter, using cancer as a paradigm, we discuss how IDP conformational dynamics and the resultant conformational noise can modulate phenotypic switching. Thus, contrary to the prevailing wisdom that phenotypic switching is highly deterministic (has a genetic underpinning) in cancer, emerging evidence suggests that non-genetic mechanisms, at least in part due to the conformational noise, may also be a confounding factor in phenotypic switching.
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Affiliation(s)
- Vivek Kulkarni
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Prakash Kulkarni
- Department of Medical Oncology and Therapeutics Research, City of Hope National Medical Center, Duarte, CA, United States.
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Oldfield CJ, Uversky VN, Dunker AK, Kurgan L. Introduction to intrinsically disordered proteins and regions. Proteins 2019. [DOI: 10.1016/b978-0-12-816348-1.00001-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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23
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The solvent side of proteinaceous membrane-less organelles in light of aqueous two-phase systems. Int J Biol Macromol 2018; 117:1224-1251. [PMID: 29890250 DOI: 10.1016/j.ijbiomac.2018.06.030] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Accepted: 06/07/2018] [Indexed: 12/29/2022]
Abstract
Water represents a common denominator for liquid-liquid phase transitions leading to the formation of the polymer-based aqueous two-phase systems (ATPSs) and a set of the proteinaceous membrane-less organelles (PMLOs). ATPSs have a broad range of biotechnological applications, whereas PMLOs play a number of crucial roles in cellular compartmentalization and often represent a cellular response to the stress. Since ATPSs and PMLOs contain high concentrations of polymers (such as polyethylene glycol (PEG), polypropylene glycol (PPG), Ucon, and polyvinylpyrrolidone (PVP), Dextran, or Ficoll) or biopolymers (peptides, proteins and nucleic acids), it is expected that the separated phases of these systems are characterized by the noticeable changes in the solvent properties of water. These changes in solvent properties can drive partitioning of various compounds (proteins, nucleic acids, organic low-molecular weight molecules, metal ions, etc.) between the phases of ATPSs or between the PMLOs and their surroundings. Although there is a sizable literature on the properties of the ATPS phases, much less is currently known about PMLOs. In this perspective article, we first represent liquid-liquid phase transitions in water, discuss different types of biphasic (or multiphasic) systems in water, and introduce various PMLOs and some of their properties. Then, some basic characteristics of polymer-based ATPSs are presented, with the major focus being on the current understanding of various properties of ATPS phases and solvent properties of water inside them. Finally, similarities and differences between the polymer-based ATPSs and biological PMLOs are discussed.
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Darling AL, Liu Y, Oldfield CJ, Uversky VN. Intrinsically Disordered Proteome of Human Membrane-Less Organelles. Proteomics 2017; 18:e1700193. [PMID: 29068531 DOI: 10.1002/pmic.201700193] [Citation(s) in RCA: 123] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 02/10/2017] [Indexed: 11/10/2022]
Abstract
It is recognized now that various proteinaceous membrane-less organelles (PMLOs) are commonly found in cytoplasm, nucleus, and mitochondria of various eukaryotic cells (as well as in the chloroplasts of plant cells). Being different from the "traditional" membrane-encapsulated organelles, such as chloroplasts, endoplasmic reticulum, Golgi apparatus, lysosomes, mitochondria, nucleus, and vacuoles, PMLOs solve the cellular need to facilitate and regulate molecular interactions via reversible and controllable isolation of target molecules in specialized compartments. PMLOs possess liquid-like behavior and are believed to be formed as a result of biological liquid-liquid phase transitions (LLPTs, also known as liquid-liquid phase separation), where an intricate interplay between RNA and intrinsically disordered proteins (IDPs) or hybrid proteins containing ordered domains and intrinsically disordered protein regions (IDPRs) may play an important role. This review analyzes the prevalence of intrinsic disorder in proteins associated with various PMLOs found in human cells and considers some of the functional roles of IDPs/IDPRs in biogenesis of these organelles.
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Affiliation(s)
- April L Darling
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| | - Yun Liu
- Guangdong Provincial Key Laboratory for Plant Epigenetics, Shenzhen Key Laboratory of Microbial Genetic Engineering, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, Guangdong, P. R. China
| | | | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, USA.,Institute for Biological Instrumentation, Russian Academy of Sciences, Moscow Region, Russia
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25
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Uversky VN. The roles of intrinsic disorder-based liquid-liquid phase transitions in the "Dr. Jekyll-Mr. Hyde" behavior of proteins involved in amyotrophic lateral sclerosis and frontotemporal lobar degeneration. Autophagy 2017; 13:2115-2162. [PMID: 28980860 DOI: 10.1080/15548627.2017.1384889] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Pathological developments leading to amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) are associated with misbehavior of several key proteins, such as SOD1 (superoxide dismutase 1), TARDBP/TDP-43, FUS, C9orf72, and dipeptide repeat proteins generated as a result of the translation of the intronic hexanucleotide expansions in the C9orf72 gene, PFN1 (profilin 1), GLE1 (GLE1, RNA export mediator), PURA (purine rich element binding protein A), FLCN (folliculin), RBM45 (RNA binding motif protein 45), SS18L1/CREST, HNRNPA1 (heterogeneous nuclear ribonucleoprotein A1), HNRNPA2B1 (heterogeneous nuclear ribonucleoprotein A2/B1), ATXN2 (ataxin 2), MAPT (microtubule associated protein tau), and TIA1 (TIA1 cytotoxic granule associated RNA binding protein). Although these proteins are structurally and functionally different and have rather different pathological functions, they all possess some levels of intrinsic disorder and are either directly engaged in or are at least related to the physiological liquid-liquid phase transitions (LLPTs) leading to the formation of various proteinaceous membrane-less organelles (PMLOs), both normal and pathological. This review describes the normal and pathological functions of these ALS- and FTLD-related proteins, describes their major structural properties, glances at their intrinsic disorder status, and analyzes the involvement of these proteins in the formation of normal and pathological PMLOs, with the ultimate goal of better understanding the roles of LLPTs and intrinsic disorder in the "Dr. Jekyll-Mr. Hyde" behavior of those proteins.
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Affiliation(s)
- Vladimir N Uversky
- a Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute , Morsani College of Medicine , University of South Florida , Tampa , FL , USA.,b Institute for Biological Instrumentation of the Russian Academy of Sciences , Pushchino, Moscow region , Russia
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26
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Johnson CL, Solovyova AS, Hecht O, Macdonald C, Waller H, Grossmann JG, Moore GR, Lakey JH. The Two-State Prehensile Tail of the Antibacterial Toxin Colicin N. Biophys J 2017; 113:1673-1684. [PMID: 29045862 PMCID: PMC5647543 DOI: 10.1016/j.bpj.2017.08.030] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 07/26/2017] [Accepted: 08/02/2017] [Indexed: 12/16/2022] Open
Abstract
Intrinsically disordered regions within proteins are critical elements in many biomolecular interactions and signaling pathways. Antibacterial toxins of the colicin family, which could provide new antibiotic functions against resistant bacteria, contain disordered N-terminal translocation domains (T-domains) that are essential for receptor binding and the penetration of the Escherichia coli outer membrane. Here we investigate the conformational behavior of the T-domain of colicin N (ColN-T) to understand why such domains are widespread in toxins that target Gram-negative bacteria. Like some other intrinsically disordered proteins in the solution state of the protein, ColN-T shows dual recognition, initially interacting with other domains of the same colicin N molecule and later, during cell killing, binding to two different receptors, OmpF and TolA, in the target bacterium. ColN-T is invisible in the high-resolution x-ray model and yet accounts for 90 of the toxin's 387 amino acid residues. To reveal its solution structure that underlies such a dynamic and complex system, we carried out mutagenic, biochemical, hydrodynamic and structural studies using analytical ultracentrifugation, NMR, and small-angle x-ray scattering on full-length ColN and its fragments. The structure was accurately modeled from small-angle x-ray scattering data by treating ColN as a flexible system, namely by the ensemble optimization method, which enables a distribution of conformations to be included in the final model. The results reveal, to our knowledge, for the first time the dynamic structure of a colicin T-domain. ColN-T is in dynamic equilibrium between a compact form, showing specific self-recognition and resistance to proteolysis, and an extended form, which most likely allows for effective receptor binding.
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Affiliation(s)
- Christopher L Johnson
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, The Medical School, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Alexandra S Solovyova
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, The Medical School, Newcastle University, Newcastle upon Tyne, United Kingdom.
| | - Olli Hecht
- Centre for Structural and Molecular Biology, School of Chemistry, University of East Anglia, Norwich, United Kingdom
| | - Colin Macdonald
- Centre for Structural and Molecular Biology, School of Chemistry, University of East Anglia, Norwich, United Kingdom
| | - Helen Waller
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, The Medical School, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - J Günter Grossmann
- Institute of Integrative Biology, Structural and Chemical Biology, Liverpool, United Kingdom
| | - Geoffrey R Moore
- Centre for Structural and Molecular Biology, School of Chemistry, University of East Anglia, Norwich, United Kingdom
| | - Jeremy H Lakey
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, The Medical School, Newcastle University, Newcastle upon Tyne, United Kingdom
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27
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Uversky VN. Paradoxes and wonders of intrinsic disorder: Stability of instability. INTRINSICALLY DISORDERED PROTEINS 2017; 5:e1327757. [PMID: 30250771 DOI: 10.1080/21690707.2017.1327757] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 04/10/2017] [Indexed: 01/03/2023]
Abstract
This article continues a series of short comments on the paradoxes and wonders of the protein intrinsic disorder phenomenon by introducing the "stability of instability" paradox. Intrinsically disordered proteins (IDPs) are characterized by the lack of stable 3D-structure, and, as a result, have an exceptional ability to sustain exposure to extremely harsh environmental conditions (an illustration of the "you cannot break what is already broken" principle). Extended IDPs are known to possess extreme thermal and acid stability and are able either to keep their functionality under these extreme conditions or to rapidly regain their functionality after returning to the normal conditions. Furthermore, sturdiness of intrinsic disorder and its capability to "ignore" harsh conditions provides some interesting and important advantages to its carriers, at the molecular (e.g., the cell wall-anchored accumulation-associated protein playing a crucial role in intercellular adhesion within the biofilm of Staphylococcus epidermidis), supramolecular (e.g., protein complexes, biologic liquid-liquid phase transitions, and proteinaceous membrane-less organelles), and organismal levels (e.g., the recently popularized case of the microscopic animals, tardigrades, or water bears, that use intrinsically disordered proteins to survive desiccation).
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Affiliation(s)
- Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, USA.,Institute for Biological Instrumentation, Russian Academy of Sciences, Pushchino, Moscow Region, Russia
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28
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Poznar M, Hołubowicz R, Wojtas M, Gapiński J, Banachowicz E, Patkowski A, Ożyhar A, Dobryszycki P. Structural properties of the intrinsically disordered, multiple calcium ion-binding otolith matrix macromolecule-64 (OMM-64). BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2017; 1865:1358-1371. [PMID: 28866388 DOI: 10.1016/j.bbapap.2017.08.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 08/28/2017] [Indexed: 01/28/2023]
Abstract
Fish otoliths are calcium carbonate biominerals that are involved in hearing and balance sensing. An organic matrix plays a crucial role in their formation. Otolith matrix macromolecule-64 (OMM-64) is a highly acidic, calcium-binding protein (CBP) found in rainbow trout otoliths. It is a component of high-molecular-weight aggregates, which influence the size, shape and polymorph of calcium carbonate in vitro. In this study, a protocol for the efficient expression and purification of OMM-64 was developed. For the first time, the complete structural characteristics of OMM-64 were described. Various biophysical methods were combined to show that OMM-64 occurs as an intrinsically disordered monomer. Under denaturing conditions (pH, temperature) OMM-64 exhibits folding propensity. It was determined that OMM-64 binds approximately 61 calcium ions with millimolar affinity. The folding-unfolding experiments showed that calcium ions induced the collapse of OMM-64. The effect of other counter ions present in trout endolymph on OMM-64 conformational changes was studied. The significance of disordered properties of OMM-64 and the possible function of this protein is discussed.
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Affiliation(s)
- Monika Poznar
- Wrocław University of Science and Technology, Faculty of Chemistry, Department of Biochemistry, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland
| | - Rafał Hołubowicz
- Wrocław University of Science and Technology, Faculty of Chemistry, Department of Biochemistry, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland
| | - Magdalena Wojtas
- Wrocław University of Science and Technology, Faculty of Chemistry, Department of Biochemistry, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland
| | - Jacek Gapiński
- A. Mickiewicz University, Faculty of Physics, Molecular Biophysics Division, Umultowska 85, 61-614, Poznań, Poland
| | - Ewa Banachowicz
- A. Mickiewicz University, Faculty of Physics, Molecular Biophysics Division, Umultowska 85, 61-614, Poznań, Poland
| | - Adam Patkowski
- A. Mickiewicz University, Faculty of Physics, Molecular Biophysics Division, Umultowska 85, 61-614, Poznań, Poland
| | - Andrzej Ożyhar
- Wrocław University of Science and Technology, Faculty of Chemistry, Department of Biochemistry, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland
| | - Piotr Dobryszycki
- Wrocław University of Science and Technology, Faculty of Chemistry, Department of Biochemistry, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
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29
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Uversky VN. Intrinsic Disorder, Protein-Protein Interactions, and Disease. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2017; 110:85-121. [PMID: 29413001 DOI: 10.1016/bs.apcsb.2017.06.005] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
It is recognized now that biologically active proteins without stable tertiary structure (known as intrinsically disordered proteins, IDPs) and hybrid proteins containing ordered domains and intrinsically disordered protein regions (IDPRs) are important players found in any given proteome. These IDPs/IDPRs possess functions that complement functional repertoire of their ordered counterparts, being commonly related to recognition, as well as control and regulation of various signaling pathways. They are interaction masters, being able to utilize a wide spectrum of interaction mechanisms, ranging from induced folding to formation of fuzzy complexes where significant levels of disorder are preserved, to polyvalent stochastic interactions playing crucial roles in the liquid-liquid phase transitions leading to the formation of proteinaceous membrane-less organelles. IDPs/IDPRs are tightly controlled themselves via various means, including alternative splicing, precisely controlled expression and degradation, binding to specific partners, and posttranslational modifications. Distortions in the regulation and control of IDPs/IDPRs, as well as their aberrant interactivity are commonly associated with various human diseases. This review presents some aspects of the intrinsic disorder-based functionality and dysfunctionality, paying special attention to the normal and pathological protein-protein interactions.
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Affiliation(s)
- Vladimir N Uversky
- USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, United States; Institute for Biological Instrumentation, Russian Academy of Sciences, Pushchino, Moscow Region, Russia.
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30
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English LR, Tilton EC, Ricard BJ, Whitten ST. Intrinsic α helix propensities compact hydrodynamic radii in intrinsically disordered proteins. Proteins 2017; 85:296-311. [PMID: 27936491 DOI: 10.1002/prot.25222] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 10/31/2016] [Accepted: 11/21/2016] [Indexed: 12/27/2022]
Abstract
Proteins that lack tertiary stability under normal conditions, known as intrinsically disordered, exhibit a wide range of biological activities. Molecular descriptions for the biology of intrinsically disordered proteins (IDPs) consequently rely on disordered structural models, which in turn require experiments that assess the origins to structural features observed. For example, while hydrodynamic size is mostly insensitive to sequence composition in chemically denatured proteins, IDPs show strong sequence-specific effects in the hydrodynamic radius (Rh ) when measured under normal conditions. To investigate sequence-modulation of IDP Rh , disordered ensembles generated by a hard sphere collision model modified with a structure-based parameterization of the solution energetics were used to parse the contributions of net charge, main chain dihedral angle bias, and excluded volume on hydrodynamic size. Ensembles for polypeptides 10-35 residues in length were then used to establish power-law scaling relationships for comparison to experimental Rh from 26 IDPs. Results showed the expected outcomes of increased hydrodynamic size from increases in excluded volume and net charge, and compaction from chain-solvent interactions. Chain bias representing intrinsic preferences for α helix and polyproline II (PPII ), however, modulated Rh with intricate dependence on the simulated propensities. PPII propensities at levels expected in IDPs correlated with heightened Rh sensitivity to even weak α helix propensities, indicating bias for common (φ, ψ) are important determinants of hydrodynamic size. Moreover, data show that IDP Rh can be predicted from sequence with good accuracy from a small set of physicochemical properties, namely intrinsic conformational propensities and net charge. Proteins 2017; 85:296-311. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Lance R English
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, Texas
| | - Erin C Tilton
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, Texas
| | - Benjamin J Ricard
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, Texas
| | - Steven T Whitten
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, Texas
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31
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Protein intrinsic disorder-based liquid-liquid phase transitions in biological systems: Complex coacervates and membrane-less organelles. Adv Colloid Interface Sci 2017; 239:97-114. [PMID: 27291647 DOI: 10.1016/j.cis.2016.05.012] [Citation(s) in RCA: 153] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2016] [Accepted: 05/24/2016] [Indexed: 12/18/2022]
Abstract
It is clear now that eukaryotic cells contain numerous membrane-less organelles, many of which are formed in response to changes in the cellular environment. Being typically liquid in nature, many of these organelles can be described as products of the reversible and highly controlled liquid-liquid phase transitions in biological systems. Many of these membrane-less organelles are complex coacervates containing (almost invariantly) intrinsically disordered proteins and often nucleic acids. It seems that the lack of stable structure in major proteinaceous constituents of these organelles is crucial for the formation of phase-separated droplets. This review considers several biologically relevant liquid-liquid phase transitions, introduces some general features attributed to intrinsically disordered proteins, represents several illustrative examples of intrinsic disorder-based phase separation, and provides some reasons for the abundance of intrinsically disordered proteins in organelles formed as a result of biological liquid-liquid phase transitions.
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32
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Hibino E, Inoue R, Sugiyama M, Kuwahara J, Matsuzaki K, Hoshino M. Interaction between intrinsically disordered regions in transcription factors Sp1 and TAF4. Protein Sci 2016; 25:2006-2017. [PMID: 27515574 PMCID: PMC5079245 DOI: 10.1002/pro.3013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2016] [Accepted: 08/08/2016] [Indexed: 11/09/2022]
Abstract
The expression of eukaryotic genes is precisely controlled by specific interactions between general transcription initiation factors and gene-specific transcriptional activators. The general transcription factor TFIID, which plays an essential role in mediating transcriptional activation, is a multisubunit complex comprising the TATA box-binding protein (TBP) and multiple TBP-associated factors (TAFs). On the other hand, biochemical and genetic approaches have shown that the promoter-specific transcriptional activator Sp1 has the ability to interact with one of the components of TFIID, the TBP-associated factor TAF4. We herein report the structural details of the glutamine-rich domains (Q-domains) of Sp1 and TAF4 using circular dichroism (CD) and heteronuclear magnetic resonance (NMR) spectroscopy. We found that the two Q-domains of Sp1 and four Q-domains of TAF4 were disordered under physiological conditions. We also quantitatively analyzed the interaction between the Q-domains of Sp1 and TAF4 by NMR and surface plasmon resonance, and detected a weak but specific association between them. Nevertheless, a detailed analysis of CD spectra suggested that any significant conformational change did not occur concomitantly with this association, at least at the level of the overall secondary structure. These results may represent a prominent and exceptional binding mode for the IDPs, which are not categorized in a well-accepted concept of "coupled folding and binding."
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Affiliation(s)
- Emi Hibino
- Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-Shimoadachi, Sakyo-Ku, Kyoto, 606-8501, Japan
| | - Rintaro Inoue
- Research Reactor Institute, Kyoto University, Kumatori, Sennan-Gun, Osaka, 590-0494, Japan
| | - Masaaki Sugiyama
- Research Reactor Institute, Kyoto University, Kumatori, Sennan-Gun, Osaka, 590-0494, Japan
| | - Jun Kuwahara
- Faculty of Pharmaceutical Sciences, Doshisha Women's University, Kodo, Kyotanabe City, 610-0395, Japan
| | - Katsumi Matsuzaki
- Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-Shimoadachi, Sakyo-Ku, Kyoto, 606-8501, Japan
| | - Masaru Hoshino
- Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-Shimoadachi, Sakyo-Ku, Kyoto, 606-8501, Japan.
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33
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Kolonko M, Ożga K, Hołubowicz R, Taube M, Kozak M, Ożyhar A, Greb-Markiewicz B. Intrinsic Disorder of the C-Terminal Domain of Drosophila Methoprene-Tolerant Protein. PLoS One 2016; 11:e0162950. [PMID: 27657508 PMCID: PMC5033490 DOI: 10.1371/journal.pone.0162950] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2016] [Accepted: 08/31/2016] [Indexed: 12/21/2022] Open
Abstract
Methoprene tolerant protein (Met) has recently been confirmed as the long-sought juvenile hormone (JH) receptor. This protein plays a significant role in the cross-talk of the 20-hydroxyecdysone (20E) and JH signalling pathways, which are important for control of insect development and maturation. Met belongs to the basic helix-loop-helix/Per-Arnt-Sim (bHLH-PAS) family of transcription factors. In these proteins, bHLH domains are typically responsible for DNA binding and dimerization, whereas the PAS domains are crucial for the choice of dimerization partner and the specificity of target gene activation. The C-terminal region is usually responsible for the regulation of protein complex activity. The sequence of the Met C-terminal region (MetC) is not homologous to any sequence deposited in the Protein Data Bank (PDB) and has not been structurally characterized to date. In this study, we show that the MetC exhibits properties typical for an intrinsically disordered protein (IDP). The final averaged structure obtained with small angle X-ray scattering (SAXS) experiments indicates that intrinsically disordered MetC exists in an extended conformation. This extended shape and the long unfolded regions characterise proteins with high flexibility and dynamics. Therefore, we suggest that the multiplicity of conformations adopted by the disordered MetC is crucial for its activity as a biological switch modulating the cross-talk of different signalling pathways in insects.
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Affiliation(s)
- Marta Kolonko
- Department of Biochemistry, Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50–370, Wrocław, Poland
| | - Katarzyna Ożga
- Department of Biochemistry, Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50–370, Wrocław, Poland
| | - Rafał Hołubowicz
- Department of Biochemistry, Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50–370, Wrocław, Poland
| | - Michał Taube
- Joint Laboratory for SAXS studies, Faculty of Physics, Adam Mickiewicz University, Umultowska 85, 61–614, Poznań, Poland
| | - Maciej Kozak
- Joint Laboratory for SAXS studies, Faculty of Physics, Adam Mickiewicz University, Umultowska 85, 61–614, Poznań, Poland
- Department of Macromolecular Physics, Faculty of Physics, Adam Mickiewicz University, Umultowska 85, 61–614, Poznań, Poland
| | - Andrzej Ożyhar
- Department of Biochemistry, Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50–370, Wrocław, Poland
| | - Beata Greb-Markiewicz
- Department of Biochemistry, Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50–370, Wrocław, Poland
- * E-mail:
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34
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Uversky VN. Dancing Protein Clouds: The Strange Biology and Chaotic Physics of Intrinsically Disordered Proteins. J Biol Chem 2016; 291:6681-8. [PMID: 26851286 DOI: 10.1074/jbc.r115.685859] [Citation(s) in RCA: 139] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Biologically active but floppy proteins represent a new reality of modern protein science. These intrinsically disordered proteins (IDPs) and hybrid proteins containing ordered and intrinsically disordered protein regions (IDPRs) constitute a noticeable part of any given proteome. Functionally, they complement ordered proteins, and their conformational flexibility and structural plasticity allow them to perform impossible tricks and be engaged in biological activities that are inaccessible to well folded proteins with their unique structures. The major goals of this minireview are to show that, despite their simplified amino acid sequences, IDPs/IDPRs are complex entities often resembling chaotic systems, are structurally and functionally heterogeneous, and can be considered an important part of the structure-function continuum. Furthermore, IDPs/IDPRs are everywhere, and are ubiquitously engaged in various interactions characterized by a wide spectrum of binding scenarios and an even wider spectrum of structural and functional outputs.
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Affiliation(s)
- Vladimir N Uversky
- From the Department of Molecular Medicine, USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, Florida 33612, the Biological Sciences Department, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia, the Institute for Biological Instrumentation, Russian Academy of Sciences, 142292 Pushchino, Moscow Region, Russia, and the Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg, Russian Federation
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35
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Tomasso ME, Tarver MJ, Devarajan D, Whitten ST. Hydrodynamic Radii of Intrinsically Disordered Proteins Determined from Experimental Polyproline II Propensities. PLoS Comput Biol 2016; 12:e1004686. [PMID: 26727467 PMCID: PMC4699819 DOI: 10.1371/journal.pcbi.1004686] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 12/01/2015] [Indexed: 11/18/2022] Open
Abstract
The properties of disordered proteins are thought to depend on intrinsic conformational propensities for polyproline II (PPII) structure. While intrinsic PPII propensities have been measured for the common biological amino acids in short peptides, the ability of these experimentally determined propensities to quantitatively reproduce structural behavior in intrinsically disordered proteins (IDPs) has not been established. Presented here are results from molecular simulations of disordered proteins showing that the hydrodynamic radius (Rh) can be predicted from experimental PPII propensities with good agreement, even when charge-based considerations are omitted. The simulations demonstrate that Rh and chain propensity for PPII structure are linked via a simple power-law scaling relationship, which was tested using the experimental Rh of 22 IDPs covering a wide range of peptide lengths, net charge, and sequence composition. Charge effects on Rh were found to be generally weak when compared to PPII effects on Rh. Results from this study indicate that the hydrodynamic dimensions of IDPs are evidence of considerable sequence-dependent backbone propensities for PPII structure that qualitatively, if not quantitatively, match conformational propensities measured in peptides. Molecular models of disordered protein structures are needed to elucidate the functional mechanisms of intrinsically disordered proteins, a class of proteins implicated in many disease pathologies and human health issues. Several studies have measured intrinsic conformational propensities for polyproline II helix, a key structural motif of disordered proteins, in short peptides. Whether or not these experimental polyproline II propensities, which vary by amino acid type, reproduce structural behavior in intrinsically disordered proteins has yet to be demonstrated. Presented here are simulation results showing that polyproline II propensities from short peptides accurately describe sequence-dependent variability in the hydrodynamic dimensions of intrinsically disordered proteins. Good agreement was observed from a simple molecular model even when charge-based considerations were ignored, predicting that global organization of disordered protein structure is strongly dependent on intrinsic conformational propensities and, for many intrinsically disordered proteins, modulated only weakly by coulombic effects.
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Affiliation(s)
- Maria E. Tomasso
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, Texas, United States of America
| | - Micheal J. Tarver
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, Texas, United States of America
| | - Deepa Devarajan
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, Texas, United States of America
| | - Steven T. Whitten
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, Texas, United States of America
- * E-mail:
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Permyakov SE, Permyakov EA, Uversky VN. Intrinsically disordered caldesmon binds calmodulin via the "buttons on a string" mechanism. PeerJ 2015; 3:e1265. [PMID: 26417545 PMCID: PMC4582948 DOI: 10.7717/peerj.1265] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 09/03/2015] [Indexed: 01/27/2023] Open
Abstract
We show here that chicken gizzard caldesmon (CaD) and its C-terminal domain (residues 636–771, CaD136) are intrinsically disordered proteins. The computational and experimental analyses of the wild type CaD136 and series of its single tryptophan mutants (W674A, W707A, and W737A) and a double tryptophan mutant (W674A/W707A) suggested that although the interaction of CaD136 with calmodulin (CaM) can be driven by the non-specific electrostatic attraction between these oppositely charged molecules, the specificity of CaD136-CaM binding is likely to be determined by the specific packing of important CaD136 tryptophan residues at the CaD136-CaM interface. It is suggested that this interaction can be described as the “buttons on a charged string” model, where the electrostatic attraction between the intrinsically disordered CaD136 and the CaM is solidified in a “snapping buttons” manner by specific packing of the CaD136 “pliable buttons” (which are the short segments of fluctuating local structure condensed around the tryptophan residues) at the CaD136-CaM interface. Our data also show that all three “buttons” are important for binding, since mutation of any of the tryptophans affects CaD136-CaM binding and since CaD136 remains CaM-buttoned even when two of the three tryptophans are mutated to alanines.
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Affiliation(s)
- Sergei E Permyakov
- Protein Research Group, Institute for Biological Instrumentation, Russian Academy of Sciences , Pushchino, Moscow Region , Russia
| | - Eugene A Permyakov
- Protein Research Group, Institute for Biological Instrumentation, Russian Academy of Sciences , Pushchino, Moscow Region , Russia
| | - Vladimir N Uversky
- Protein Research Group, Institute for Biological Instrumentation, Russian Academy of Sciences , Pushchino, Moscow Region , Russia ; Department of Molecular Medicine, University of South Florida , Tampa, FL , USA
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Biophysical Methods to Investigate Intrinsically Disordered Proteins: Avoiding an “Elephant and Blind Men” Situation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 870:215-60. [DOI: 10.1007/978-3-319-20164-1_7] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Uversky VN. The multifaceted roles of intrinsic disorder in protein complexes. FEBS Lett 2015; 589:2498-506. [PMID: 26073257 DOI: 10.1016/j.febslet.2015.06.004] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 06/02/2015] [Indexed: 01/08/2023]
Abstract
Intrinsically disordered proteins (IDPs) and intrinsically disordered protein regions (IDPRs) are important constituents of many protein complexes, playing various structural, functional, and regulatory roles. In such disorder-based protein complexes, functional disorder is used both internally (for assembly, movement, and functional regulation of the different parts of a given complex) and externally (for interactions of a complex with its external regulators). In complex assembly, IDPs/IDPRs serve as the molecular glue that cements complexes or as highly flexible scaffolds. Disorder defines the order of complex assembly and the ability of a protein to be involved in polyvalent interactions. It is at the heart of various binding mechanisms and interaction modes ascribed to IDPs. Disorder in protein complexes is related to multifarious applications of induced folding and induced functional unfolding, or defines the entropic chain activities, such as stochastic machines and binding rheostats. This review opens a FEBS Letters Special Issue on Dynamics, Flexibility, and Intrinsic Disorder in protein assemblies and represents a brief overview of intricate roles played by IDPs and IDPRs in various aspects of protein complexes.
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Affiliation(s)
- Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, USA; Institute for Biological Instrumentation, Russian Academy of Sciences, Pushchino, Moscow Region, Russian Federation; Department of Biology, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
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Balu R, Knott R, Cowieson NP, Elvin CM, Hill AJ, Choudhury NR, Dutta NK. Structural ensembles reveal intrinsic disorder for the multi-stimuli responsive bio-mimetic protein Rec1-resilin. Sci Rep 2015; 5:10896. [PMID: 26042819 PMCID: PMC4455251 DOI: 10.1038/srep10896] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 04/21/2015] [Indexed: 01/08/2023] Open
Abstract
Rec1-resilin is the first recombinant resilin-mimetic protein polymer, synthesized from exon-1 of the Drosophila melanogaster gene CG15920 that has demonstrated unusual multi-stimuli responsiveness in aqueous solution. Crosslinked hydrogels of Rec1-resilin have also displayed remarkable mechanical properties including near-perfect rubber-like elasticity. The structural basis of these extraordinary properties is not clearly understood. Here we combine a computational and experimental investigation to examine structural ensembles of Rec1-resilin in aqueous solution. The structure of Rec1-resilin in aqueous solutions is investigated experimentally using circular dichroism (CD) spectroscopy and small angle X-ray scattering (SAXS). Both bench-top and synchrotron SAXS are employed to extract structural data sets of Rec1-resilin and to confirm their validity. Computational approaches have been applied to these experimental data sets in order to extract quantitative information about structural ensembles including radius of gyration, pair-distance distribution function, and the fractal dimension. The present work confirms that Rec1-resilin is an intrinsically disordered protein (IDP) that displays equilibrium structural qualities between those of a structured globular protein and a denatured protein. The ensemble optimization method (EOM) analysis reveals a single conformational population with partial compactness. This work provides new insight into the structural ensembles of Rec1-resilin in solution.
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Affiliation(s)
- Rajkamal Balu
- Ian Wark Research Institute, University of South Australia, Mawson Lakes campus, Mawson lakes, South Australia 5095, Australia
| | - Robert Knott
- ANSTO, Private Mail Bag, Kirrawee, New South Wales 2232, Australia
| | - Nathan P. Cowieson
- Centre for Synchrotron Science, Monash University, Victoria 3800, Australia
| | - Christopher M. Elvin
- CSIRO Agriculture, Level 6, Queensland Bioscience Precinct, St Lucia, Queensland 4067, Australia
| | - Anita J. Hill
- CSIRO Manufacturing, Clayton, Victoria 3168, Australia
| | - Namita R. Choudhury
- Ian Wark Research Institute, University of South Australia, Mawson Lakes campus, Mawson lakes, South Australia 5095, Australia
| | - Naba K. Dutta
- Ian Wark Research Institute, University of South Australia, Mawson Lakes campus, Mawson lakes, South Australia 5095, Australia
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Perez RB, Tischer A, Auton M, Whitten ST. Alanine and proline content modulate global sensitivity to discrete perturbations in disordered proteins. Proteins 2014; 82:3373-84. [PMID: 25244701 DOI: 10.1002/prot.24692] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Revised: 08/26/2014] [Accepted: 09/16/2014] [Indexed: 01/12/2023]
Abstract
Molecular transduction of biological signals is understood primarily in terms of the cooperative structural transitions of protein macromolecules, providing a mechanism through which discrete local structure perturbations affect global macromolecular properties. The recognition that proteins lacking tertiary stability, commonly referred to as intrinsically disordered proteins (IDPs), mediate key signaling pathways suggests that protein structures without cooperative intramolecular interactions may also have the ability to couple local and global structure changes. Presented here are results from experiments that measured and tested the ability of disordered proteins to couple local changes in structure to global changes in structure. Using the intrinsically disordered N-terminal region of the p53 protein as an experimental model, a set of proline (PRO) and alanine (ALA) to glycine (GLY) substitution variants were designed to modulate backbone conformational propensities without introducing non-native intramolecular interactions. The hydrodynamic radius (R(h)) was used to monitor changes in global structure. Circular dichroism spectroscopy showed that the GLY substitutions decreased polyproline II (PP(II)) propensities relative to the wild type, as expected, and fluorescence methods indicated that substitution-induced changes in R(h) were not associated with folding. The experiments showed that changes in local PP(II) structure cause changes in R(h) that are variable and that depend on the intrinsic chain propensities of PRO and ALA residues, demonstrating a mechanism for coupling local and global structure changes. Molecular simulations that model our results were used to extend the analysis to other proteins and illustrate the generality of the observed PRO and alanine effects on the structures of IDPs.
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Affiliation(s)
- Romel B Perez
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, Texas
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Uversky VN. Proteins without unique 3D structures: biotechnological applications of intrinsically unstable/disordered proteins. Biotechnol J 2014; 10:356-66. [PMID: 25287424 DOI: 10.1002/biot.201400374] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Revised: 07/23/2014] [Accepted: 08/27/2014] [Indexed: 11/09/2022]
Abstract
Intrinsically disordered proteins (IDPs) and intrinsically disordered protein regions (IDPRs) are functional proteins or regions that do not have unique 3D structures under functional conditions. Therefore, from the viewpoint of their lack of stable 3D structure, IDPs/IDPRs are inherently unstable. As much as structure and function of normal ordered globular proteins are determined by their amino acid sequences, the lack of unique 3D structure in IDPs/IDPRs and their disorder-based functionality are also encoded in the amino acid sequences. Because of their specific sequence features and distinctive conformational behavior, these intrinsically unstable proteins or regions have several applications in biotechnology. This review introduces some of the most characteristic features of IDPs/IDPRs (such as peculiarities of amino acid sequences of these proteins and regions, their major structural features, and peculiar responses to changes in their environment) and describes how these features can be used in the biotechnology, for example for the proteome-wide analysis of the abundance of extended IDPs, for recombinant protein isolation and purification, as polypeptide nanoparticles for drug delivery, as solubilization tools, and as thermally sensitive carriers of active peptides and proteins.
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Affiliation(s)
- Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, USA; Faculty of Science, Biology Department, King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia; Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia; Institute for Biological Instrumentation, Russian Academy of Sciences, Pushchino, Moscow Region, Russia.
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Sá-Moura B, Simões AM, Fraga J, Fernandes H, Abreu IA, Botelho HM, Gomes CM, Marques AJ, Dohmen RJ, Ramos PC, Macedo-Ribeiro S. Biochemical and biophysical characterization of recombinant yeast proteasome maturation factor ump1. Comput Struct Biotechnol J 2013; 7:e201304006. [PMID: 24688736 PMCID: PMC3962104 DOI: 10.5936/csbj.201304006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2013] [Revised: 08/16/2013] [Accepted: 08/19/2013] [Indexed: 11/22/2022] Open
Abstract
Protein degradation is essential for maintaining cellular homeostasis. The proteasome is the central enzyme responsible for non-lysosomal protein degradation in eukaryotic cells. Although proteasome assembly is not yet completely understood, a number of cofactors required for proper assembly and maturation have been identified. Ump is a short-lived maturation factor required for the efficient biogenesis of the 20S proteasome. Upon the association of the two precursor complexes, Ump is encased and is rapidly degraded after the proteolytic sites in the interior of the nascent proteasome are activated. In order to further understand the mechanisms behind proteasomal maturation, we expressed and purified yeast Ump in E. coli for biophysical and structural analysis. We show that recombinant Ump is purified as a mixture of different oligomeric species and that oligomerization is mediated by intermolecular disulfide bond formation involving the only cysteine residue present in the protein. Furthermore, a combination of bioinformatic, biochemical and structural analysis revealed that Ump shows characteristics of an intrinsically disordered protein, which might become structured only upon interaction with the proteasome subunits.
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Affiliation(s)
- Bebiana Sá-Moura
- IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
| | - Ana Marisa Simões
- IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
| | - Joana Fraga
- IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
| | - Humberto Fernandes
- Centre for Molecular and Structural Biomedicine, CBME/IBB, LA, Portugal ; Current address: Biophysics Section, Department of Life Sciences, Imperial College, London, UK
| | - Isabel A Abreu
- IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal ; Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Portugal
| | - Hugo M Botelho
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Portugal ; Current address: BioFIG - Centre for Biodiversity, Functional and Integrative Genomics, Faculty of Sciences, University of Lisboa, Campo Grande 1749-016 Lisboa, Portugal
| | - Cláudio M Gomes
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Portugal
| | - António J Marques
- Centre for Molecular and Structural Biomedicine, CBME/IBB, LA, Portugal ; Current address: Immunodiagnostic Systems, Core Technology, 10 Didcot Way, Boldon, NE35 9PD, UK
| | - R Jürgen Dohmen
- Institute for Genetics, University of Cologne, Zülpicher Str. 47, D-50674 Cologne, Germany
| | - Paula C Ramos
- Centre for Molecular and Structural Biomedicine, CBME/IBB, LA, Portugal ; Institute for Genetics, University of Cologne, Zülpicher Str. 47, D-50674 Cologne, Germany
| | - Sandra Macedo-Ribeiro
- IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
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Uversky VN. Hypothesis: The unfolding power of protein dielectricity. INTRINSICALLY DISORDERED PROTEINS 2013; 1:e25725. [PMID: 28516018 PMCID: PMC5424796 DOI: 10.4161/idp.25725] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Revised: 07/02/2013] [Accepted: 07/11/2013] [Indexed: 01/25/2023]
Abstract
A hypothesis is proposed on a potential role of protein dielectricity as an unfolding factor in protein-protein interactions. It is suggested that large protein complexes and aggregation seeds can unfold target proteins by virtue of their effect on the dielectric properties of water at the protein-solvent interface. Here, similar to the effect of membrane surfaces, protein surface can cause decrease in the local dielectric constant of solvent and thereby induce structural changes in a target protein approaching this surface. Some potential implementations of this hypothetical mechanism are also discussed.
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Affiliation(s)
- Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute; Morsani College of Medicine; University of South Florida; Tampa, FL USA.,Institute for Biological Instrumentation; Russian Academy of Sciences; Moscow Region, Russia
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44
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Guharoy M, Szabo B, Martos SC, Kosol S, Tompa P. Intrinsic Structural Disorder in Cytoskeletal Proteins. Cytoskeleton (Hoboken) 2013; 70:550-71. [DOI: 10.1002/cm.21118] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 05/26/2013] [Accepted: 05/29/2013] [Indexed: 12/11/2022]
Affiliation(s)
- Mainak Guharoy
- VIB Department of Structural Biology; Vrije Universiteit Brussel; Brussels Belgium
| | - Beata Szabo
- Institute of Enzymology; Research Centre for Natural Sciences, Hungarian Academy of Sciences; Budapest Hungary
| | | | - Simone Kosol
- VIB Department of Structural Biology; Vrije Universiteit Brussel; Brussels Belgium
| | - Peter Tompa
- VIB Department of Structural Biology; Vrije Universiteit Brussel; Brussels Belgium
- Institute of Enzymology; Research Centre for Natural Sciences, Hungarian Academy of Sciences; Budapest Hungary
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45
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Uversky VN. A decade and a half of protein intrinsic disorder: biology still waits for physics. Protein Sci 2013; 22:693-724. [PMID: 23553817 PMCID: PMC3690711 DOI: 10.1002/pro.2261] [Citation(s) in RCA: 364] [Impact Index Per Article: 33.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Revised: 03/23/2013] [Accepted: 03/25/2013] [Indexed: 12/28/2022]
Abstract
The abundant existence of proteins and regions that possess specific functions without being uniquely folded into unique 3D structures has become accepted by a significant number of protein scientists. Sequences of these intrinsically disordered proteins (IDPs) and IDP regions (IDPRs) are characterized by a number of specific features, such as low overall hydrophobicity and high net charge which makes these proteins predictable. IDPs/IDPRs possess large hydrodynamic volumes, low contents of ordered secondary structure, and are characterized by high structural heterogeneity. They are very flexible, but some may undergo disorder to order transitions in the presence of natural ligands. The degree of these structural rearrangements varies over a very wide range. IDPs/IDPRs are tightly controlled under the normal conditions and have numerous specific functions that complement functions of ordered proteins and domains. When lacking proper control, they have multiple roles in pathogenesis of various human diseases. Gaining structural and functional information about these proteins is a challenge, since they do not typically "freeze" while their "pictures are taken." However, despite or perhaps because of the experimental challenges, these fuzzy objects with fuzzy structures and fuzzy functions are among the most interesting targets for modern protein research. This review briefly summarizes some of the recent advances in this exciting field and considers some of the basic lessons learned from the analysis of physics, chemistry, and biology of IDPs.
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Affiliation(s)
- Vladimir N Uversky
- Department of Molecular Medicine, USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, Florida 33612, USA.
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Abstract
Inteins are intervening protein sequences that undergo self-excision from a precursor protein with the concomitant ligation of the flanking polypeptides. Split inteins are expressed in two separated halves, and the recognition and association of two halves are the first crucial step for initiating trans-splicing. In the present study, we carried out the structural and thermodynamic analysis on the interaction of two halves of DnaE split intein from Synechocystis sp. PCC6803. Both isolated halves (IN and IC) are disordered and undergo conformational transition from disorder to order upon association. ITC (isothermal titration calorimetry) reveals that the highly favourable enthalpy change drives the association of the two halves, overcoming the unfavourable entropy change. The high flexibility of two fragments and the marked thermodynamic preference provide a robust association for the formation of the well-folded IN/IC complex, which is the basis for reconstituting the trans-splicing activity of DnaE split intein.
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47
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Structural basis for the interaction of unstructured neuron specific substrates neuromodulin and neurogranin with Calmodulin. Sci Rep 2013; 3:1392. [PMID: 23462742 PMCID: PMC3589724 DOI: 10.1038/srep01392] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2012] [Accepted: 02/21/2013] [Indexed: 01/07/2023] Open
Abstract
Neuromodulin (Nm) and neurogranin (Ng) are neuron-specific substrates of protein kinase C (PKC). Their interactions with Calmodulin (CaM) are crucial for learning and memory formation in neurons. Here, we report the structure of IQ peptides (24aa) of Nm/Ng complexed with CaM and their functional studies with full-length proteins. Nm/Ng and their respective IQ peptides are intrinsically unstructured; however, upon binding with CaM, IQ motifs adopt a helical conformation. Ser41 (Ser36) of Nm (Ng) is located in a negatively charged pocket in the apo CaM and, when phosphorylated, it will repel Nm/Ng from CaM. These observations explain the mechanism by which PKC-induced Ser phosphorylation blocks the association of Nm/Ng with CaM and interrupts several learning- and memory-associated functions. Moreover, the present study identified Arg as a key CaM interacting residue from Nm/Ng. This residue is crucial for CaM-mediated function, as evidenced by the inability of the Ng mutant (Arg-to-Ala) to potentiate synaptic transmission in CA1 hippocampal neurons.
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Unusual biophysics of intrinsically disordered proteins. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2012; 1834:932-51. [PMID: 23269364 DOI: 10.1016/j.bbapap.2012.12.008] [Citation(s) in RCA: 413] [Impact Index Per Article: 34.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Revised: 11/21/2012] [Accepted: 12/12/2012] [Indexed: 02/08/2023]
Abstract
Research of a past decade and a half leaves no doubt that complete understanding of protein functionality requires close consideration of the fact that many functional proteins do not have well-folded structures. These intrinsically disordered proteins (IDPs) and proteins with intrinsically disordered protein regions (IDPRs) are highly abundant in nature and play a number of crucial roles in a living cell. Their functions, which are typically associated with a wide range of intermolecular interactions where IDPs possess remarkable binding promiscuity, complement functional repertoire of ordered proteins. All this requires a close attention to the peculiarities of biophysics of these proteins. In this review, some key biophysical features of IDPs are covered. In addition to the peculiar sequence characteristics of IDPs these biophysical features include sequential, structural, and spatiotemporal heterogeneity of IDPs; their rough and relatively flat energy landscapes; their ability to undergo both induced folding and induced unfolding; the ability to interact specifically with structurally unrelated partners; the ability to gain different structures at binding to different partners; and the ability to keep essential amount of disorder even in the bound form. IDPs are also characterized by the "turned-out" response to the changes in their environment, where they gain some structure under conditions resulting in denaturation or even unfolding of ordered proteins. It is proposed that the heterogeneous spatiotemporal structure of IDPs/IDPRs can be described as a set of foldons, inducible foldons, semi-foldons, non-foldons, and unfoldons. They may lose their function when folded, and activation of some IDPs is associated with the awaking of the dormant disorder. It is possible that IDPs represent the "edge of chaos" systems which operate in a region between order and complete randomness or chaos, where the complexity is maximal. This article is part of a Special Issue entitled: The emerging dynamic view of proteins: Protein plasticity in allostery, evolution and self-assembly.
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Receveur-Brechot V, Durand D. How random are intrinsically disordered proteins? A small angle scattering perspective. Curr Protein Pept Sci 2012; 13:55-75. [PMID: 22044150 PMCID: PMC3394175 DOI: 10.2174/138920312799277901] [Citation(s) in RCA: 267] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2011] [Revised: 08/04/2011] [Accepted: 08/04/2011] [Indexed: 01/08/2023]
Abstract
While the crucial role of intrinsically disordered proteins (IDPs) in the cell cycle is now recognized, deciphering their molecular mode of action at the structural level still remains highly challenging and requires a combination of many biophysical approaches. Among them, small angle X-ray scattering (SAXS) has been extremely successful in the last decade and has become an indispensable technique for addressing many of the fundamental questions regarding the activities of IDPs. After introducing some experimental issues specific to IDPs and in relation to the latest technical developments, this article presents the interest of the theory of polymer physics to evaluate the flexibility of fully disordered proteins. The different strategies to obtain 3-dimensional models of IDPs, free in solution and associated in a complex, are then reviewed. Indeed, recent computational advances have made it possible to readily extract maximum information from the scattering curve with a special emphasis on highly flexible systems, such as multidomain proteins and IDPs. Furthermore, integrated computational approaches now enable the generation of ensembles of conformers to translate the unique flexible characteristics of IDPs by taking into consideration the constraints of more and more various complementary experiment. In particular, a combination of SAXS with high-resolution techniques, such as x-ray crystallography and NMR, allows us to provide reliable models and to gain unique structural insights about the protein over multiple structural scales. The latest neutron scattering experiments also promise new advances in the study of the conformational changes of macromolecules involving more complex systems.
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50
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Size-exclusion chromatography in structural analysis of intrinsically disordered proteins. Methods Mol Biol 2012; 896:179-94. [PMID: 22821524 DOI: 10.1007/978-1-4614-3704-8_11] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Gel-filtration chromatography, also known as size-exclusion chromatography (SEC) or gel-permeation chromatography, is a useful tool for structural and conformational analyses of intrinsically disordered proteins (IDPs). SEC can be utilized for the estimation of the hydrodynamic dimensions of a given IDP, for evaluation of the association state, for the analysis of IDP interactions with binding partners, and for the induced folding studies. It also can be used to physically separate IDP conformers based on their hydrodynamic dimensions, thus providing a unique possibility for the independent analysis of their physicochemical properties.
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