1
|
Tants JN, Schlundt A. Advances, Applications, and Perspectives in Small-Angle X-ray Scattering of RNA. Chembiochem 2023; 24:e202300110. [PMID: 37466350 DOI: 10.1002/cbic.202300110] [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: 02/10/2023] [Revised: 04/22/2023] [Indexed: 07/20/2023]
Abstract
RNAs exhibit a plethora of functions far beyond transmitting genetic information. Often, RNA functions are entailed in their structure, be it as a regulatory switch, protein binding site, or providing catalytic activity. Structural information is a prerequisite for a full understanding of RNA-regulatory mechanisms. Owing to the inherent dynamics, size, and instability of RNA, its structure determination remains challenging. Methods such as NMR spectroscopy, X-ray crystallography, and cryo-electron microscopy can provide high-resolution structures; however, their limitations make structure determination, even for small RNAs, cumbersome, if at all possible. Although at a low resolution, small-angle X-ray scattering (SAXS) has proven valuable in advancing structure determination of RNAs as a complementary method, which is also applicable to large-sized RNAs. Here, we review the technological and methodological advancements of RNA SAXS. We provide examples of the powerful inclusion of SAXS in structural biology and discuss possible future applications to large RNAs.
Collapse
Affiliation(s)
- Jan-Niklas Tants
- Goethe University Frankfurt, Institute for Molecular Biosciences and Biomagnetic Resonance Centre (BMRZ), Max-von-Laue-Str. 9, 60438, Frankfurt, Germany
| | - Andreas Schlundt
- Goethe University Frankfurt, Institute for Molecular Biosciences and Biomagnetic Resonance Centre (BMRZ), Max-von-Laue-Str. 9, 60438, Frankfurt, Germany
| |
Collapse
|
2
|
Data quality assurance, model validation, and data sharing for biomolecular structures from small-angle scattering. Methods Enzymol 2022; 678:1-22. [PMID: 36641205 DOI: 10.1016/bs.mie.2022.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Key to small-angle scattering (SAS) maturing and becoming a mainstream structural biology technique was the work done by the SAS community to establish standards for data quality, model validation and data sharing. Through a consultative process spanning more than a decade and a half, guidelines for publication have been established that include criteria for evaluating data quality and for model validation. In this process gaps were identified that stimulated innovation and development of new tools, for example new measures of model ambiguity and of the goodness-of-fit of a model to SAS data that complement the traditional global fit parameter χ2. The need for a global repository for biomolecular SAS data and models was identified and the SASBDB was established as a searchable, curated, freely accessible, downloadable database of experimental data, experimental conditions, sample details, derived models, and their fit to the data. Importantly, the SASBDB uses a common dictionary format that supports archiving of structures solved using integrative methods to support seamless data exchange with a federated system of public databanks that includes the world-wide Protein Data Bank (wwPDB) as the major repository for structural biology. Thus, biomolecular SAS is now well-positioned to achieve its full potential as a mainstream structural biology technique contributing at the frontier of integrative structural biology and meeting "best practice" standards for data quality assurance and data sharing.
Collapse
|
3
|
Delhommel F, Martínez-Lumbreras S, Sattler M. Combining NMR, SAXS and SANS to characterize the structure and dynamics of protein complexes. Methods Enzymol 2022; 678:263-297. [PMID: 36641211 DOI: 10.1016/bs.mie.2022.09.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Understanding the structure and dynamics of biological macromolecules is essential to decipher the molecular mechanisms that underlie cellular functions. The description of structure and conformational dynamics often requires the integration of complementary techniques. In this review, we highlight the utility of combining nuclear magnetic resonance (NMR) spectroscopy with small angle scattering (SAS) to characterize these challenging biomolecular systems. NMR can assess the structure and conformational dynamics of multidomain proteins, RNAs and biomolecular complexes. It can efficiently provide information on interaction surfaces, long-distance restraints and relative domain orientations at residue-level resolution. Such information can be readily combined with high-resolution structural data available on subcomponents of biomolecular assemblies. Moreover, NMR is a powerful tool to characterize the dynamics of biomolecules on a wide range of timescales, from nanoseconds to seconds. On the other hand, SAS approaches provide global information on the size and shape of biomolecules and on the ensemble of all conformations present in solution. Therefore, NMR and SAS provide complementary data that are uniquely suited to investigate dynamic biomolecular assemblies. Here, we briefly review the type of data that can be obtained by both techniques and describe different approaches that can be used to combine them to characterize biomolecular assemblies. We then provide guidelines on which experiments are best suited depending on the type of system studied, ranging from fully rigid complexes, dynamic structures that interconvert between defined conformations and systems with very high structural heterogeneity.
Collapse
Affiliation(s)
- Florent Delhommel
- Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany; Bavarian NMR Center, Department of Chemistry, Technical University of Munich, Garching, Germany
| | - Santiago Martínez-Lumbreras
- Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany; Bavarian NMR Center, Department of Chemistry, Technical University of Munich, Garching, Germany
| | - Michael Sattler
- Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany; Bavarian NMR Center, Department of Chemistry, Technical University of Munich, Garching, Germany.
| |
Collapse
|
4
|
Macošek J, Simon B, Linse JB, Jagtap PKA, Winter SL, Foot J, Lapouge K, Perez K, Rettel M, Ivanović MT, Masiewicz P, Murciano B, Savitski MM, Loedige I, Hub JS, Gabel F, Hennig J. Structure and dynamics of the quaternary hunchback mRNA translation repression complex. Nucleic Acids Res 2021; 49:8866-8885. [PMID: 34329466 PMCID: PMC8421216 DOI: 10.1093/nar/gkab635] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 07/05/2021] [Accepted: 07/27/2021] [Indexed: 01/02/2023] Open
Abstract
A key regulatory process during Drosophila development is the localized suppression of the hunchback mRNA translation at the posterior, which gives rise to a hunchback gradient governing the formation of the anterior-posterior body axis. This suppression is achieved by a concerted action of Brain Tumour (Brat), Pumilio (Pum) and Nanos. Each protein is necessary for proper Drosophila development. The RNA contacts have been elucidated for the proteins individually in several atomic-resolution structures. However, the interplay of all three proteins during RNA suppression remains a long-standing open question. Here, we characterize the quaternary complex of the RNA-binding domains of Brat, Pum and Nanos with hunchback mRNA by combining NMR spectroscopy, SANS/SAXS, XL/MS with MD simulations and ITC assays. The quaternary hunchback mRNA suppression complex comprising the RNA binding domains is flexible with unoccupied nucleotides functioning as a flexible linker between the Brat and Pum-Nanos moieties of the complex. Moreover, the presence of the Pum-HD/Nanos-ZnF complex has no effect on the equilibrium RNA binding affinity of the Brat RNA binding domain. This is in accordance with previous studies, which showed that Brat can suppress mRNA independently and is distributed uniformly throughout the embryo.
Collapse
Affiliation(s)
- Jakub Macošek
- Structural and Computational Biology Unit, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Bernd Simon
- Structural and Computational Biology Unit, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Johanna-Barbara Linse
- Theoretical Physics and Center for Biophysics, Saarland University, Saarbrücken 66123, Germany
| | - Pravin Kumar Ankush Jagtap
- Structural and Computational Biology Unit, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Sophie L Winter
- Structural and Computational Biology Unit, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Jaelle Foot
- Structural and Computational Biology Unit, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Karine Lapouge
- Protein Expression and Purification Core Facility, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Kathryn Perez
- Protein Expression and Purification Core Facility, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Mandy Rettel
- Proteomics Core Facility, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Miloš T Ivanović
- Theoretical Physics and Center for Biophysics, Saarland University, Saarbrücken 66123, Germany
| | - Pawel Masiewicz
- Structural and Computational Biology Unit, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Brice Murciano
- Structural and Computational Biology Unit, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Mikhail M Savitski
- Proteomics Core Facility, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Inga Loedige
- Structural and Computational Biology Unit, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Jochen S Hub
- Theoretical Physics and Center for Biophysics, Saarland University, Saarbrücken 66123, Germany
| | - Frank Gabel
- Institut Biologie Structurale, University Grenoble Alpes, CEA, CNRS, Grenoble 38044, France
| | - Janosch Hennig
- Structural and Computational Biology Unit, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany.,Chair of Biochemistry IV, Biophysical Chemistry, University of Bayreuth, Universitätsstrasse 30, 95447 Bayreuth, Germany
| |
Collapse
|
5
|
Kursula P. Small-angle X-ray scattering for the proteomics community: current overview and future potential. Expert Rev Proteomics 2021; 18:415-422. [PMID: 34210208 DOI: 10.1080/14789450.2021.1951242] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Introduction: Proteins are biological nanoparticles. For structural proteomics and hybrid structural biology, complementary methods are required that allow both high throughput and accurate automated data analysis. Small-angle X-ray scattering (SAXS) is a method for observing the size and shape of particles, such as proteins and complexes, in solution. SAXS data can be used to model both the structure, oligomeric state, conformational changes, and flexibility of biomolecular samples.Areas covered: The key principles of SAXS, its sample requirements, and its current and future applications for structural proteomics are briefly reviewed. Recent technical developments in SAXS experiments are discussed, and future potential of the method in structural proteomics is evaluated.Expert opinion: SAXS is a method suitable for several aspects of integrative structural proteomics, with current technical developments allowing for higher throughput and time-resolved studies, as well as the analysis of complex samples, such as membrane proteins. Increasing automation and streamlined data analysis are expected to equip SAXS for structure-based screening workflows. Originally, structural genomics had a heavy focus on folded, crystallizable proteins and complexes - SAXS is a method allowing an expansion of this focus to flexible and disordered systems.
Collapse
Affiliation(s)
- Petri Kursula
- Department of Biomedicine, University of Bergen, Bergen, Norway.,Biocenter Oulu & Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| |
Collapse
|
6
|
Metwalli E, Götz K, Lages S, Bär C, Zech T, Noll DM, Schuldes I, Schindler T, Prihoda A, Lang H, Grasser J, Jacques M, Didier L, Cyril A, Martel A, Porcar L, Unruh T. A novel experimental approach for nanostructure analysis: simultaneous small-angle X-ray and neutron scattering. J Appl Crystallogr 2020; 53:722-733. [PMID: 32684887 PMCID: PMC7312133 DOI: 10.1107/s1600576720005208] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 04/13/2020] [Indexed: 12/31/2022] Open
Abstract
Exploiting small-angle X-ray and neutron scattering (SAXS/SANS) on the same sample volume at the same time provides complementary nanoscale structural information in two different contrast situations. Unlike an independent experimental approach, the truly combined SAXS/SANS experimental approach ensures the exactness of the probed samples, particularly for in situ studies. Here, an advanced portable SAXS system that is dimensionally suitable for installation in the D22 zone of ILL is introduced. The SAXS apparatus is based on a Rigaku switchable copper/molybdenum microfocus rotating-anode X-ray generator and a DECTRIS detector with a changeable sample-to-detector distance of up to 1.6 m in a vacuum chamber. A case study is presented to demonstrate the uniqueness of the newly established method. Temporal structural rearrangements of both the organic stabilizing agent and organically capped gold colloidal particles during gold nanoparticle growth are simultaneously probed, enabling the immediate acquisition of correlated structural information. The new nano-analytical method will open the way for real-time investigations of a wide range of innovative nanomaterials and will enable comprehensive in situ studies on biological systems. The potential development of a fully automated SAXS/SANS system with a common control environment and additional sample environments, permitting a continual and efficient operation of the system by ILL users, is also introduced.
Collapse
Affiliation(s)
- Ezzeldin Metwalli
- Institute for Crystallography and Structural Physics, Friedrich-Alexander-Universität Erlangen–Nürnberg, Staudtstrasse 3, Erlangen, 91058, Germany
| | - Klaus Götz
- Institute for Crystallography and Structural Physics, Friedrich-Alexander-Universität Erlangen–Nürnberg, Staudtstrasse 3, Erlangen, 91058, Germany
- Center for Nanoanalysis and Electron Microscopy (CENEM) and Interdisciplinary Center for Nanostructured Films (IZNF), Friedrich-Alexander-Universität Erlangen–Nürnberg (FAU), Cauerstrasse 3, Erlangen, 91058, Germany
| | - Sebastian Lages
- Institute for Crystallography and Structural Physics, Friedrich-Alexander-Universität Erlangen–Nürnberg, Staudtstrasse 3, Erlangen, 91058, Germany
| | - Christian Bär
- Institute for Crystallography and Structural Physics, Friedrich-Alexander-Universität Erlangen–Nürnberg, Staudtstrasse 3, Erlangen, 91058, Germany
| | - Tobias Zech
- Institute for Crystallography and Structural Physics, Friedrich-Alexander-Universität Erlangen–Nürnberg, Staudtstrasse 3, Erlangen, 91058, Germany
- Center for Nanoanalysis and Electron Microscopy (CENEM) and Interdisciplinary Center for Nanostructured Films (IZNF), Friedrich-Alexander-Universität Erlangen–Nürnberg (FAU), Cauerstrasse 3, Erlangen, 91058, Germany
| | - Dennis M. Noll
- Institute for Crystallography and Structural Physics, Friedrich-Alexander-Universität Erlangen–Nürnberg, Staudtstrasse 3, Erlangen, 91058, Germany
| | - Isabel Schuldes
- Institute for Crystallography and Structural Physics, Friedrich-Alexander-Universität Erlangen–Nürnberg, Staudtstrasse 3, Erlangen, 91058, Germany
| | - Torben Schindler
- Institute for Crystallography and Structural Physics, Friedrich-Alexander-Universität Erlangen–Nürnberg, Staudtstrasse 3, Erlangen, 91058, Germany
| | - Annemarie Prihoda
- Institute for Crystallography and Structural Physics, Friedrich-Alexander-Universität Erlangen–Nürnberg, Staudtstrasse 3, Erlangen, 91058, Germany
- Center for Nanoanalysis and Electron Microscopy (CENEM) and Interdisciplinary Center for Nanostructured Films (IZNF), Friedrich-Alexander-Universität Erlangen–Nürnberg (FAU), Cauerstrasse 3, Erlangen, 91058, Germany
| | - Herbert Lang
- Institute for Crystallography and Structural Physics, Friedrich-Alexander-Universität Erlangen–Nürnberg, Staudtstrasse 3, Erlangen, 91058, Germany
| | - Jürgen Grasser
- Institute for Crystallography and Structural Physics, Friedrich-Alexander-Universität Erlangen–Nürnberg, Staudtstrasse 3, Erlangen, 91058, Germany
| | - Mark Jacques
- Institut Laue–Langevin, 71 Avenue des Martyrs, Grenoble, 38042, France
| | - Luc Didier
- Institut Laue–Langevin, 71 Avenue des Martyrs, Grenoble, 38042, France
| | - Amrouni Cyril
- Institut Laue–Langevin, 71 Avenue des Martyrs, Grenoble, 38042, France
| | - Anne Martel
- Institut Laue–Langevin, 71 Avenue des Martyrs, Grenoble, 38042, France
| | - Lionel Porcar
- Institut Laue–Langevin, 71 Avenue des Martyrs, Grenoble, 38042, France
| | - Tobias Unruh
- Institute for Crystallography and Structural Physics, Friedrich-Alexander-Universität Erlangen–Nürnberg, Staudtstrasse 3, Erlangen, 91058, Germany
- Center for Nanoanalysis and Electron Microscopy (CENEM) and Interdisciplinary Center for Nanostructured Films (IZNF), Friedrich-Alexander-Universität Erlangen–Nürnberg (FAU), Cauerstrasse 3, Erlangen, 91058, Germany
| |
Collapse
|
7
|
Delhommel F, Gabel F, Sattler M. Current approaches for integrating solution NMR spectroscopy and small-angle scattering to study the structure and dynamics of biomolecular complexes. J Mol Biol 2020; 432:2890-2912. [DOI: 10.1016/j.jmb.2020.03.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 02/27/2020] [Accepted: 03/10/2020] [Indexed: 01/24/2023]
|
8
|
Rout MP, Sali A. Principles for Integrative Structural Biology Studies. Cell 2020; 177:1384-1403. [PMID: 31150619 DOI: 10.1016/j.cell.2019.05.016] [Citation(s) in RCA: 165] [Impact Index Per Article: 41.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 04/24/2019] [Accepted: 05/06/2019] [Indexed: 12/22/2022]
Abstract
Integrative structure determination is a powerful approach to modeling the structures of biological systems based on data produced by multiple experimental and theoretical methods, with implications for our understanding of cellular biology and drug discovery. This Primer introduces the theory and methods of integrative approaches, emphasizing the kinds of data that can be effectively included in developing models and using the nuclear pore complex as an example to illustrate the practice and challenges involved. These guidelines are intended to aid the researcher in understanding and applying integrative structural methods to systems of their interest and thus take advantage of this rapidly evolving field.
Collapse
Affiliation(s)
- Michael P Rout
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY 10065, USA.
| | - Andrej Sali
- Department of Bioengineering and Therapeutic Sciences, Department of Pharmaceutical Chemistry, California Institute for Quantitative Biosciences, Byers Hall, 1700 4th Street, Suite 503B, University of California, San Francisco, San Francisco, CA 94158, USA.
| |
Collapse
|
9
|
Integrative Structural Biology of Protein-RNA Complexes. Structure 2020; 28:6-28. [DOI: 10.1016/j.str.2019.11.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 11/17/2019] [Accepted: 11/27/2019] [Indexed: 12/16/2022]
|
10
|
Chen PC, Shevchuk R, Strnad FM, Lorenz C, Karge L, Gilles R, Stadler AM, Hennig J, Hub JS. Combined Small-Angle X-ray and Neutron Scattering Restraints in Molecular Dynamics Simulations. J Chem Theory Comput 2019; 15:4687-4698. [DOI: 10.1021/acs.jctc.9b00292] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Po-chia Chen
- Structural and Computational Biology Unit, EMBL Heidelberg, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Roman Shevchuk
- Institute for Microbiology and Genetics, Georg-August-Universität Göttingen, Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany
| | - Felix M. Strnad
- Institute for Microbiology and Genetics, Georg-August-Universität Göttingen, Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany
| | - Charlotte Lorenz
- Jülich Centre for Neutron Science (JCNS-1) and Institute for Complex Systems ICS (ICS-1), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen, Germany
| | - Lukas Karge
- Heinz Maier-Leibnitz Zentrum, Technische Universität München, Lichtenbergstrasse 1, 85748 Garching, Germany
| | - Ralph Gilles
- Heinz Maier-Leibnitz Zentrum, Technische Universität München, Lichtenbergstrasse 1, 85748 Garching, Germany
| | - Andreas M. Stadler
- Jülich Centre for Neutron Science (JCNS-1) and Institute for Complex Systems ICS (ICS-1), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen, Germany
| | - Janosch Hennig
- Structural and Computational Biology Unit, EMBL Heidelberg, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Jochen S. Hub
- Theoretical Physics and Center for Biophysics, Saarland University, Campus E2 6, 66123 Saarbrücken, Germany
| |
Collapse
|
11
|
Brosey CA, Tainer JA. Evolving SAXS versatility: solution X-ray scattering for macromolecular architecture, functional landscapes, and integrative structural biology. Curr Opin Struct Biol 2019; 58:197-213. [PMID: 31204190 PMCID: PMC6778498 DOI: 10.1016/j.sbi.2019.04.004] [Citation(s) in RCA: 115] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 04/10/2019] [Accepted: 04/15/2019] [Indexed: 11/27/2022]
Abstract
Small-angle X-ray scattering (SAXS) has emerged as an enabling
integrative technique for comprehensive analyses of macromolecular structures
and interactions in solution. Over the past two decades, SAXS has become a
mainstay of the structural biologist’s toolbox, supplying multiplexed
measurements of molecular shape and dynamics that unveil biological function.
Here, we discuss evolving SAXS theory, methods, and applications that extend the
field of small-angle scattering beyond simple shape characterization. SAXS,
coupled with size-exclusion chromatography (SEC-SAXS) and time-resolved
(TR-SAXS) methods, is now providing high-resolution insight into macromolecular
flexibility and ensembles, delineating biophysical landscapes, and facilitating
high-throughput library screening to assess macromolecular properties and to
create opportunities for drug discovery. Looking forward, we consider SAXS in
the integrative era of hybrid structural biology methods, its potential for
illuminating cellular supramolecular and mesoscale structures, and its capacity
to complement high-throughput bioinformatics sequencing data. As advances in the
field continue, we look forward to proliferating uses of SAXS based upon its
abilities to robustly produce mechanistic insights for biology and medicine.
Collapse
Affiliation(s)
- Chris A Brosey
- Molecular and Cellular Oncology and Cancer Biology, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA.
| | - John A Tainer
- Molecular and Cellular Oncology and Cancer Biology, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA; MBIB Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
| |
Collapse
|
12
|
Oliver RC, Rolband LA, Hutchinson-Lundy AM, Afonin KA, Krueger JK. Small-Angle Scattering as a Structural Probe for Nucleic Acid Nanoparticles (NANPs) in a Dynamic Solution Environment. NANOMATERIALS (BASEL, SWITZERLAND) 2019; 9:E681. [PMID: 31052508 PMCID: PMC6566709 DOI: 10.3390/nano9050681] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 04/16/2019] [Accepted: 04/19/2019] [Indexed: 12/23/2022]
Abstract
Nucleic acid-based technologies are an emerging research focus area for pharmacological and biological studies because they are biocompatible and can be designed to produce a variety of scaffolds at the nanometer scale. The use of nucleic acids (ribonucleic acid (RNA) and/or deoxyribonucleic acid (DNA)) as building materials in programming the assemblies and their further functionalization has recently established a new exciting field of RNA and DNA nanotechnology, which have both already produced a variety of different functional nanostructures and nanodevices. It is evident that the resultant architectures require detailed structural and functional characterization and that a variety of technical approaches must be employed to promote the development of the emerging fields. Small-angle X-ray and neutron scattering (SAS) are structural characterization techniques that are well placed to determine the conformation of nucleic acid nanoparticles (NANPs) under varying solution conditions, thus allowing for the optimization of their design. SAS experiments provide information on the overall shapes and particle dimensions of macromolecules and are ideal for following conformational changes of the molecular ensemble as it behaves in solution. In addition, the inherent differences in the neutron scattering of nucleic acids, lipids, and proteins, as well as the different neutron scattering properties of the isotopes of hydrogen, combined with the ability to uniformly label biological macromolecules with deuterium, allow one to characterize the conformations and relative dispositions of the individual components within an assembly of biomolecules. This article will review the application of SAS methods and provide a summary of their successful utilization in the emerging field of NANP technology to date, as well as share our vision on its use in complementing a broad suite of structural characterization tools with some simulated results that have never been shared before.
Collapse
Affiliation(s)
- Ryan C Oliver
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA.
| | - Lewis A Rolband
- UNC Charlotte Chemistry Department, Charlotte, NC 28223, USA.
| | | | - Kirill A Afonin
- UNC Charlotte Chemistry Department, Charlotte, NC 28223, USA.
| | | |
Collapse
|
13
|
Bucciarelli S, Midtgaard SR, Nors Pedersen M, Skou S, Arleth L, Vestergaard B. Size-exclusion chromatography small-angle X-ray scattering of water soluble proteins on a laboratory instrument. J Appl Crystallogr 2018; 51:1623-1632. [PMID: 30546289 PMCID: PMC6276278 DOI: 10.1107/s1600576718014462] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 10/13/2018] [Indexed: 11/16/2022] Open
Abstract
Coupling of size-exclusion chromatography with biological solution small-angle X-ray scattering (SEC-SAXS) on dedicated synchrotron beamlines enables structural analysis of challenging samples such as labile proteins and low-affinity complexes. For this reason, the approach has gained increased popularity during the past decade. Transportation of perishable samples to synchrotrons might, however, compromise the experiments, and the limited availability of synchrotron beamtime renders iterative sample optimization tedious and lengthy. Here, the successful setup of laboratory-based SEC-SAXS is described in a proof-of-concept study. It is demonstrated that sufficient quality data can be obtained on a laboratory instrument with small sample consumption, comparable to typical synchrotron SEC-SAXS demands. UV/vis measurements directly on the SAXS exposure cell ensure accurate concentration determination, crucial for direct molecular weight determination from the scattering data. The absence of radiation damage implies that the sample can be fractionated and subjected to complementary analysis available at the home institution after SEC-SAXS. Laboratory-based SEC-SAXS opens the field for analysis of biological samples at the home institution, thus increasing productivity of biostructural research. It may further ensure that synchrotron beamtime is used primarily for the most suitable and optimized samples.
Collapse
Affiliation(s)
- Saskia Bucciarelli
- Department of Drug Design and Pharmacology, University of Copenhagen, Denmark
| | - Søren Roi Midtgaard
- Structural Biophysics, X-ray and Neutron Science, The Niels Bohr Institute, University of Copenhagen, Denmark
| | - Martin Nors Pedersen
- Structural Biophysics, X-ray and Neutron Science, The Niels Bohr Institute, University of Copenhagen, Denmark
| | | | - Lise Arleth
- Structural Biophysics, X-ray and Neutron Science, The Niels Bohr Institute, University of Copenhagen, Denmark
| | - Bente Vestergaard
- Department of Drug Design and Pharmacology, University of Copenhagen, Denmark
| |
Collapse
|
14
|
Chen PC, Hennig J. The role of small-angle scattering in structure-based screening applications. Biophys Rev 2018; 10:1295-1310. [PMID: 30306530 PMCID: PMC6233350 DOI: 10.1007/s12551-018-0464-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 09/04/2018] [Indexed: 12/16/2022] Open
Abstract
In many biomolecular interactions, changes in the assembly states and structural conformations of participants can act as a complementary reporter of binding to functional and thermodynamic assays. This structural information is captured by a number of structural biology and biophysical techniques that are viable either as primary screens in small-scale applications or as secondary screens to complement higher throughput methods. In particular, small-angle X-ray scattering (SAXS) reports the average distance distribution between all atoms after orientational averaging. Such information is important when for example investigating conformational changes involved in inhibitory and regulatory mechanisms where binding events do not necessarily cause functional changes. Thus, we summarise here the current and prospective capabilities of SAXS-based screening in the context of other methods that yield structural information. Broad guidelines are also provided to assist readers in preparing screening protocols that are tailored to available X-ray sources.
Collapse
Affiliation(s)
- Po-Chia Chen
- Structural and Computational Biology Unit, European Molecular Biology Laboratory Heidelberg, Meyerhofstrasse 1, 69126, Heidelberg, Germany.
| | - Janosch Hennig
- Structural and Computational Biology Unit, European Molecular Biology Laboratory Heidelberg, Meyerhofstrasse 1, 69126, Heidelberg, Germany.
| |
Collapse
|
15
|
Nerli S, McShan AC, Sgourakis NG. Chemical shift-based methods in NMR structure determination. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2018; 106-107:1-25. [PMID: 31047599 PMCID: PMC6788782 DOI: 10.1016/j.pnmrs.2018.03.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 03/09/2018] [Accepted: 03/09/2018] [Indexed: 05/08/2023]
Abstract
Chemical shifts are highly sensitive probes harnessed by NMR spectroscopists and structural biologists as conformational parameters to characterize a range of biological molecules. Traditionally, assignment of chemical shifts has been a labor-intensive process requiring numerous samples and a suite of multidimensional experiments. Over the past two decades, the development of complementary computational approaches has bolstered the analysis, interpretation and utilization of chemical shifts for elucidation of high resolution protein and nucleic acid structures. Here, we review the development and application of chemical shift-based methods for structure determination with a focus on ab initio fragment assembly, comparative modeling, oligomeric systems, and automated assignment methods. Throughout our discussion, we point out practical uses, as well as advantages and caveats, of using chemical shifts in structure modeling. We additionally highlight (i) hybrid methods that employ chemical shifts with other types of NMR restraints (residual dipolar couplings, paramagnetic relaxation enhancements and pseudocontact shifts) that allow for improved accuracy and resolution of generated 3D structures, (ii) the utilization of chemical shifts to model the structures of sparsely populated excited states, and (iii) modeling of sidechain conformations. Finally, we briefly discuss the advantages of contemporary methods that employ sparse NMR data recorded using site-specific isotope labeling schemes for chemical shift-driven structure determination of larger molecules. With this review, we aim to emphasize the accessibility and versatility of chemical shifts for structure determination of challenging biological systems, and to point out emerging areas of development that lead us towards the next generation of tools.
Collapse
Affiliation(s)
- Santrupti Nerli
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA 95064, United States; Department of Computer Science, University of California Santa Cruz, Santa Cruz, CA 95064, United States
| | - Andrew C McShan
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA 95064, United States
| | - Nikolaos G Sgourakis
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA 95064, United States.
| |
Collapse
|
16
|
Chen PC, Masiewicz P, Rybin V, Svergun D, Hennig J. A General Small-Angle X-ray Scattering-Based Screening Protocol Validated for Protein-RNA Interactions. ACS COMBINATORIAL SCIENCE 2018; 20:197-202. [PMID: 29553252 DOI: 10.1021/acscombsci.8b00007] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We present a screening protocol utilizing small-angle X-ray scattering (SAXS) to obtain structural information on biomolecular interactions independent of prior knowledge, so as to complement affinity-based screening and provide leads for further exploration. This protocol categorizes ligand titrations by computing pairwise agreement between curves, and separately estimates affinities by quantifying complex formation as a departure from the linear sum properties of solution SAXS. The protocol is validated by sparse sequence search around the native poly uridine RNA motifs of the two-RRM domain Sex-lethal protein (Sxl). The screening of 35 RNA motifs between 4 to 10 nucleotides reveals a strong variation of resulting complexes, revealed to be preference-switching between 1:1 and 2:2 binding stoichiometries upon addition of structural modeling. Validation of select sequences in isothermal calorimetry and NMR titration retrieves domain-specific roles and function of a guanine anchor. These findings reinforce the suitability of SAXS as a complement in lead identification.
Collapse
Affiliation(s)
- Po-chia Chen
- Structural and Computational Biology Unit, EMBL Heidelberg, Meyerhofstrasse 1, 69126 Heidelberg, Germany
| | - Pawel Masiewicz
- Structural and Computational Biology Unit, EMBL Heidelberg, Meyerhofstrasse 1, 69126 Heidelberg, Germany
| | - Vladimir Rybin
- Structural and Computational Biology Unit, EMBL Heidelberg, Meyerhofstrasse 1, 69126 Heidelberg, Germany
| | - Dmitri Svergun
- EMBL Hamburg, DESY, Building 25A, Notkestraße 85, 22607 Hamburg, Germany
| | - Janosch Hennig
- Structural and Computational Biology Unit, EMBL Heidelberg, Meyerhofstrasse 1, 69126 Heidelberg, Germany
| |
Collapse
|
17
|
Tolbert M, Morgan CE, Pollum M, Crespo-Hernández CE, Li ML, Brewer G, Tolbert BS. HnRNP A1 Alters the Structure of a Conserved Enterovirus IRES Domain to Stimulate Viral Translation. J Mol Biol 2017; 429:2841-2858. [PMID: 28625847 PMCID: PMC5610934 DOI: 10.1016/j.jmb.2017.06.007] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 06/08/2017] [Accepted: 06/08/2017] [Indexed: 01/25/2023]
Abstract
Enteroviruses use a type I Internal Ribosome Entry Site (IRES) structure to facilitate protein synthesis and promote genome replication. Type I IRES elements require auxiliary host proteins to organize RNA structure for 40S ribosomal subunit assembly. Heterogeneous nuclear ribonucleoprotein A1 stimulates enterovirus 71 (EV71) translation in part through specific interactions with its stem loop II (SLII) IRES domain. Here, we determined a conjoined NMR-small angle x-ray scattering structure of the EV71 SLII domain and a mutant that significantly attenuates viral replication by abrogating hnRNP A1 interactions. Native SLII adopts a locally compact structure wherein stacking interactions in a conserved 5'-AUAGC-3' bulge preorganize the adjacent helices at nearly orthogonal orientations. Mutating the bulge sequence to 5'-ACCCC-3' ablates base stacking in the loop and globally reorients the SLII structure. Biophysical titrations reveal that the 5'-AUAGC-3' bulge undergoes a conformational change to assemble a functional hnRNP A1-RNA complex. Importantly, IRES mutations that delete the bulge impair viral translation and completely inhibit replication. Thus, this work provides key details into how an EV71 IRES structure adapts to hijack a cellular protein, and it suggests that the SLII domain is a potential target for antiviral therapy.
Collapse
Affiliation(s)
- Michele Tolbert
- Department of Chemistry, Case Western Reserve University, Cleveland, OH, 44106-7078 USA
| | - Christopher E Morgan
- Department of Chemistry, Case Western Reserve University, Cleveland, OH, 44106-7078 USA
| | - Marvin Pollum
- Department of Chemistry, Case Western Reserve University, Cleveland, OH, 44106-7078 USA
| | | | - Mei-Ling Li
- Department of Biochemistry and Molecular Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ, 08854 USA
| | - Gary Brewer
- Department of Biochemistry and Molecular Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ, 08854 USA
| | - Blanton S Tolbert
- Department of Chemistry, Case Western Reserve University, Cleveland, OH, 44106-7078 USA.
| |
Collapse
|
18
|
Sonntag M, Jagtap PKA, Simon B, Appavou MS, Geerlof A, Stehle R, Gabel F, Hennig J, Sattler M. Segmental, Domain-Selective Perdeuteration and Small-Angle Neutron Scattering for Structural Analysis of Multi-Domain Proteins. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201702904] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Miriam Sonntag
- Institute of Structural Biology; Helmholtz Zentrum München; Ingolstädter Landstr. 1 85764 Neuherberg Germany
- Center for Integrated Protein Science Munich at Chair Biomolecular NMR Spectroscopy; Department Chemie; Technische Universität München; Lichtenbergstr. 4 85747 Garching Germany
| | - Pravin Kumar Ankush Jagtap
- Institute of Structural Biology; Helmholtz Zentrum München; Ingolstädter Landstr. 1 85764 Neuherberg Germany
- Center for Integrated Protein Science Munich at Chair Biomolecular NMR Spectroscopy; Department Chemie; Technische Universität München; Lichtenbergstr. 4 85747 Garching Germany
| | - Bernd Simon
- Structural and Computational Biology Unit; European Molecular Biology Laboratory (EMBL) Heidelberg; 69117 Heidelberg Germany
| | - Marie-Sousai Appavou
- Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ); Forschungszentrum Jülich GmbH; Lichtenbergstr. 1 85748 Garching Germany
| | - Arie Geerlof
- Institute of Structural Biology; Helmholtz Zentrum München; Ingolstädter Landstr. 1 85764 Neuherberg Germany
| | - Ralf Stehle
- Center for Integrated Protein Science Munich at Chair Biomolecular NMR Spectroscopy; Department Chemie; Technische Universität München; Lichtenbergstr. 4 85747 Garching Germany
| | - Frank Gabel
- Univ. Grenoble Alpes; CEA, CNRS, IBS; 38000 Grenoble France
- Institut Laue-Langevin (ILL); Avenue des Martyrs 38042 Grenoble France
| | - Janosch Hennig
- Institute of Structural Biology; Helmholtz Zentrum München; Ingolstädter Landstr. 1 85764 Neuherberg Germany
- Structural and Computational Biology Unit; European Molecular Biology Laboratory (EMBL) Heidelberg; 69117 Heidelberg Germany
| | - Michael Sattler
- Institute of Structural Biology; Helmholtz Zentrum München; Ingolstädter Landstr. 1 85764 Neuherberg Germany
- Center for Integrated Protein Science Munich at Chair Biomolecular NMR Spectroscopy; Department Chemie; Technische Universität München; Lichtenbergstr. 4 85747 Garching Germany
| |
Collapse
|
19
|
Sonntag M, Jagtap PKA, Simon B, Appavou MS, Geerlof A, Stehle R, Gabel F, Hennig J, Sattler M. Segmental, Domain-Selective Perdeuteration and Small-Angle Neutron Scattering for Structural Analysis of Multi-Domain Proteins. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/anie.201702904] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Miriam Sonntag
- Institute of Structural Biology; Helmholtz Zentrum München; Ingolstädter Landstr. 1 85764 Neuherberg Germany
- Center for Integrated Protein Science Munich at Chair Biomolecular NMR Spectroscopy; Department Chemie; Technische Universität München; Lichtenbergstr. 4 85747 Garching Germany
| | - Pravin Kumar Ankush Jagtap
- Institute of Structural Biology; Helmholtz Zentrum München; Ingolstädter Landstr. 1 85764 Neuherberg Germany
- Center for Integrated Protein Science Munich at Chair Biomolecular NMR Spectroscopy; Department Chemie; Technische Universität München; Lichtenbergstr. 4 85747 Garching Germany
| | - Bernd Simon
- Structural and Computational Biology Unit; European Molecular Biology Laboratory (EMBL) Heidelberg; 69117 Heidelberg Germany
| | - Marie-Sousai Appavou
- Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ); Forschungszentrum Jülich GmbH; Lichtenbergstr. 1 85748 Garching Germany
| | - Arie Geerlof
- Institute of Structural Biology; Helmholtz Zentrum München; Ingolstädter Landstr. 1 85764 Neuherberg Germany
| | - Ralf Stehle
- Center for Integrated Protein Science Munich at Chair Biomolecular NMR Spectroscopy; Department Chemie; Technische Universität München; Lichtenbergstr. 4 85747 Garching Germany
| | - Frank Gabel
- Univ. Grenoble Alpes; CEA, CNRS, IBS; 38000 Grenoble France
- Institut Laue-Langevin (ILL); Avenue des Martyrs 38042 Grenoble France
| | - Janosch Hennig
- Institute of Structural Biology; Helmholtz Zentrum München; Ingolstädter Landstr. 1 85764 Neuherberg Germany
- Structural and Computational Biology Unit; European Molecular Biology Laboratory (EMBL) Heidelberg; 69117 Heidelberg Germany
| | - Michael Sattler
- Institute of Structural Biology; Helmholtz Zentrum München; Ingolstädter Landstr. 1 85764 Neuherberg Germany
- Center for Integrated Protein Science Munich at Chair Biomolecular NMR Spectroscopy; Department Chemie; Technische Universität München; Lichtenbergstr. 4 85747 Garching Germany
| |
Collapse
|
20
|
Thompson MK, Ehlinger AC, Chazin WJ. Analysis of Functional Dynamics of Modular Multidomain Proteins by SAXS and NMR. Methods Enzymol 2017; 592:49-76. [PMID: 28668130 DOI: 10.1016/bs.mie.2017.03.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Multiprotein machines drive virtually all primary cellular processes. Modular multidomain proteins are widely distributed within these dynamic complexes because they provide the flexibility needed to remodel structure as well as rapidly assemble and disassemble components of the machinery. Understanding the functional dynamics of modular multidomain proteins is a major challenge confronting structural biology today because their structure is not fixed in time. Small-angle X-ray scattering (SAXS) and nuclear magnetic resonance (NMR) spectroscopy have proven particularly useful for the analysis of the structural dynamics of modular multidomain proteins because they provide highly complementary information for characterizing the architectural landscape accessible to these proteins. SAXS provides a global snapshot of all architectural space sampled by a molecule in solution. Furthermore, SAXS is sensitive to conformational changes, organization and oligomeric states of protein assemblies, and the existence of flexibility between globular domains in multiprotein complexes. The power of NMR to characterize dynamics provides uniquely complementary information to the global snapshot of the architectural ensemble provided by SAXS because it can directly measure domain motion. In particular, NMR parameters can be used to define the diffusion of domains within modular multidomain proteins, connecting the amplitude of interdomain motion to the architectural ensemble derived from SAXS. Our laboratory has been studying the roles of modular multidomain proteins involved in human DNA replication using SAXS and NMR. Here, we present the procedure for acquiring and analyzing SAXS and NMR data, using DNA primase and replication protein A as examples.
Collapse
Affiliation(s)
- Matthew K Thompson
- Departments of Biochemistry and Chemistry, Center for Structural Biology, Vanderbilt University, Nashville, TN, United States
| | - Aaron C Ehlinger
- Departments of Biochemistry and Chemistry, Center for Structural Biology, Vanderbilt University, Nashville, TN, United States
| | - Walter J Chazin
- Departments of Biochemistry and Chemistry, Center for Structural Biology, Vanderbilt University, Nashville, TN, United States.
| |
Collapse
|
21
|
Integrated structural biology to unravel molecular mechanisms of protein-RNA recognition. Methods 2017; 118-119:119-136. [PMID: 28315749 DOI: 10.1016/j.ymeth.2017.03.015] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 02/19/2017] [Accepted: 03/13/2017] [Indexed: 12/20/2022] Open
Abstract
Recent advances in RNA sequencing technologies have greatly expanded our knowledge of the RNA landscape in cells, often with spatiotemporal resolution. These techniques identified many new (often non-coding) RNA molecules. Large-scale studies have also discovered novel RNA binding proteins (RBPs), which exhibit single or multiple RNA binding domains (RBDs) for recognition of specific sequence or structured motifs in RNA. Starting from these large-scale approaches it is crucial to unravel the molecular principles of protein-RNA recognition in ribonucleoprotein complexes (RNPs) to understand the underlying mechanisms of gene regulation. Structural biology and biophysical studies at highest possible resolution are key to elucidate molecular mechanisms of RNA recognition by RBPs and how conformational dynamics, weak interactions and cooperative binding contribute to the formation of specific, context-dependent RNPs. While large compact RNPs can be well studied by X-ray crystallography and cryo-EM, analysis of dynamics and weak interaction necessitates the use of solution methods to capture these properties. Here, we illustrate methods to study the structure and conformational dynamics of protein-RNA complexes in solution starting from the identification of interaction partners in a given RNP. Biophysical and biochemical techniques support the characterization of a protein-RNA complex and identify regions relevant in structural analysis. Nuclear magnetic resonance (NMR) is a powerful tool to gain information on folding, stability and dynamics of RNAs and characterize RNPs in solution. It provides crucial information that is complementary to the static pictures derived from other techniques. NMR can be readily combined with other solution techniques, such as small angle X-ray and/or neutron scattering (SAXS/SANS), electron paramagnetic resonance (EPR), and Förster resonance energy transfer (FRET), which provide information about overall shapes, internal domain arrangements and dynamics. Principles of protein-RNA recognition and current approaches are reviewed and illustrated with recent studies.
Collapse
|
22
|
Yadav DK, Lukavsky PJ. NMR solution structure determination of large RNA-protein complexes. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2016; 97:57-81. [PMID: 27888840 DOI: 10.1016/j.pnmrs.2016.10.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 10/04/2016] [Accepted: 10/04/2016] [Indexed: 06/06/2023]
Abstract
Structure determination of RNA-protein complexes is essential for our understanding of the multiple layers of RNA-mediated posttranscriptional regulation of gene expression. Over the past 20years, NMR spectroscopy became a key tool for structural studies of RNA-protein interactions. Here, we review the progress being made in NMR structure determination of large ribonucleoprotein assemblies. We discuss approaches for the design of RNA-protein complexes for NMR structural studies, established and emerging isotope and segmental labeling schemes suitable for large RNPs and how to gain distance restraints from NOEs, PREs and EPR and orientational information from RDCs and SAXS/SANS in such systems. The new combination of NMR measurements with MD simulations and its potential will also be discussed. Application and combination of these various methods for structure determination of large RNPs will be illustrated with three large RNA-protein complexes (>40kDa) and other interesting complexes determined in the past six and a half years.
Collapse
Affiliation(s)
- Deepak Kumar Yadav
- Central European Institute of Technology, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic
| | - Peter J Lukavsky
- Central European Institute of Technology, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic.
| |
Collapse
|
23
|
Small-angle scattering and 3D structure interpretation. Curr Opin Struct Biol 2016; 40:1-7. [DOI: 10.1016/j.sbi.2016.05.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Revised: 05/12/2016] [Accepted: 05/12/2016] [Indexed: 12/29/2022]
|
24
|
Yabukarski F, Leyrat C, Martinez N, Communie G, Ivanov I, Ribeiro EA, Buisson M, Gerard FC, Bourhis JM, Jensen MR, Bernadó P, Blackledge M, Jamin M. Ensemble Structure of the Highly Flexible Complex Formed between Vesicular Stomatitis Virus Unassembled Nucleoprotein and its Phosphoprotein Chaperone. J Mol Biol 2016; 428:2671-94. [PMID: 27107640 DOI: 10.1016/j.jmb.2016.04.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 04/06/2016] [Accepted: 04/07/2016] [Indexed: 01/08/2023]
Abstract
Nucleocapsid assembly is an essential process in the replication of the non-segmented, negative-sense RNA viruses (NNVs). Unassembled nucleoprotein (N(0)) is maintained in an RNA-free and monomeric form by its viral chaperone, the phosphoprotein (P), forming the N(0)-P complex. Our earlier work solved the structure of vesicular stomatitis virus complex formed between an N-terminally truncated N (NΔ21) and a peptide of P (P60) encompassing the N(0)-binding site, but how the full-length P interacts with N(0) remained unknown. Here, we combine several experimental biophysical methods including size exclusion chromatography with detection by light scattering and refractometry, small-angle X-ray and neutron scattering and nuclear magnetic resonance spectroscopy with molecular dynamics simulation and computational modeling to characterize the NΔ21(0)-PFL complex formed with dimeric full-length P. We show that for multi-molecular complexes, simultaneous multiple-curve fitting using small-angle neutron scattering data collected at varying contrast levels provides additional information and can help refine structural ensembles. We demonstrate that (a) vesicular stomatitis virus PFL conserves its high flexibility within the NΔ21(0)-PFL complex and interacts with NΔ21(0) only through its N-terminal extremity; (b) each protomer of P can chaperone one N(0) client protein, leading to the formation of complexes with stoichiometries 1N:P2 and 2N:P2; and (c) phosphorylation of residues Ser60, Thr62 and Ser64 provides no additional interactions with N(0) but creates a metal binding site in PNTR. A comparison with the structures of Nipah virus and Ebola virus N(0)-P core complex suggests a mechanism for the control of nucleocapsid assembly that is common to all NNVs.
Collapse
Affiliation(s)
- Filip Yabukarski
- Institut de Biologie Structurale (IBS), CEA, CNRS, Université Grenoble Alpes, Grenoble 38044, France
| | - Cedric Leyrat
- Institut de Biologie Structurale (IBS), CEA, CNRS, Université Grenoble Alpes, Grenoble 38044, France
| | - Nicolas Martinez
- Institut de Biologie Structurale (IBS), CEA, CNRS, Université Grenoble Alpes, Grenoble 38044, France; Institut Laue Langevin, Grenoble, France
| | - Guillaume Communie
- Institut de Biologie Structurale (IBS), CEA, CNRS, Université Grenoble Alpes, Grenoble 38044, France
| | - Ivan Ivanov
- Institut de Biologie Structurale (IBS), CEA, CNRS, Université Grenoble Alpes, Grenoble 38044, France; Institut Laue Langevin, Grenoble, France
| | - Euripedes A Ribeiro
- Institut de Biologie Structurale (IBS), CEA, CNRS, Université Grenoble Alpes, Grenoble 38044, France
| | - Marlyse Buisson
- Institut de Biologie Structurale (IBS), CEA, CNRS, Université Grenoble Alpes, Grenoble 38044, France; Laboratoire de Virologie, Centre Hospitalo-Universitaire de Grenoble, Grenoble, France
| | - Francine C Gerard
- Institut de Biologie Structurale (IBS), CEA, CNRS, Université Grenoble Alpes, Grenoble 38044, France
| | - Jean-Marie Bourhis
- Institut de Biologie Structurale (IBS), CEA, CNRS, Université Grenoble Alpes, Grenoble 38044, France
| | - Malene Ringkjøbing Jensen
- Institut de Biologie Structurale (IBS), CEA, CNRS, Université Grenoble Alpes, Grenoble 38044, France
| | - Pau Bernadó
- Centre de Biochimie Structurale, INSERM U1054, CNRS UMR 5048, Université Montpellier 1 and 2, Montpellier, France
| | - Martin Blackledge
- Institut de Biologie Structurale (IBS), CEA, CNRS, Université Grenoble Alpes, Grenoble 38044, France
| | - Marc Jamin
- Institut de Biologie Structurale (IBS), CEA, CNRS, Université Grenoble Alpes, Grenoble 38044, France.
| |
Collapse
|
25
|
Carlon A, Ravera E, Hennig J, Parigi G, Sattler M, Luchinat C. Improved Accuracy from Joint X-ray and NMR Refinement of a Protein-RNA Complex Structure. J Am Chem Soc 2016; 138:1601-10. [PMID: 26761154 DOI: 10.1021/jacs.5b11598] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Integrated experimental approaches play an increasingly important role in structural biology, taking advantage of the complementary information provided by different techniques. In particular, the combination of NMR data with X-ray diffraction patterns may provide accurate and precise information about local conformations not available from average-resolution X-ray structures alone. Here, we refined the structure of a ternary protein-protein-RNA complex comprising three domains, Sxl and Unr, bound to a single-stranded region derived in the msl2 mRNA. The joint X-ray and NMR refinement reveals that-despite the poor quality of the fit found for the original structural model-the NMR data can be largely accommodated within the uncertainty in the atom positioning (structural noise) from the primary X-ray data and that the overall domain arrangements and binding interfaces are preserved on passing from the crystalline state to the solution. The refinement highlights local conformational differences, which provide additional information on specific features of the structure. For example, conformational dynamics and heterogeneity observed at the interface between the CSD1 and the Sxl protein components in the ternary complex are revealed by the combination of NMR and crystallographic data. The joint refinement protocol offers unique opportunities to detect structural differences arising from various experimental conditions and reveals static or dynamic differences in the conformation of the biomolecule between the solution and the crystals.
Collapse
Affiliation(s)
- Azzurra Carlon
- Magnetic Resonance Center "CERM" and Department of Chemistry "Ugo Schiff", University of Florence and Magnetic Resonance Consortium (CIRMMP) , Via L. Sacconi 6, 50019 Sesto Fiorentino, Firenze, Italy
| | - Enrico Ravera
- Magnetic Resonance Center "CERM" and Department of Chemistry "Ugo Schiff", University of Florence and Magnetic Resonance Consortium (CIRMMP) , Via L. Sacconi 6, 50019 Sesto Fiorentino, Firenze, Italy
| | - Janosch Hennig
- Center for Integrated Protein Science Munich (CIPSM) at Department Chemie, Technische Universität München , 85747 Garching, Germany.,Institute of Structural Biology, Helmholtz Zentrum München , 85764 Neuherberg, Germany
| | - Giacomo Parigi
- Magnetic Resonance Center "CERM" and Department of Chemistry "Ugo Schiff", University of Florence and Magnetic Resonance Consortium (CIRMMP) , Via L. Sacconi 6, 50019 Sesto Fiorentino, Firenze, Italy
| | - Michael Sattler
- Center for Integrated Protein Science Munich (CIPSM) at Department Chemie, Technische Universität München , 85747 Garching, Germany.,Institute of Structural Biology, Helmholtz Zentrum München , 85764 Neuherberg, Germany
| | - Claudio Luchinat
- Magnetic Resonance Center "CERM" and Department of Chemistry "Ugo Schiff", University of Florence and Magnetic Resonance Consortium (CIRMMP) , Via L. Sacconi 6, 50019 Sesto Fiorentino, Firenze, Italy
| |
Collapse
|
26
|
Hennig J, Sattler M. Protein Expression, Purification and Crystallization of the Sxl-Unr-msl2 Ribonucleoprotein Complex. Bio Protoc 2016. [DOI: 10.21769/bioprotoc.1917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
|
27
|
Morgan CE, Meagher JL, Levengood JD, Delproposto J, Rollins C, Stuckey JA, Tolbert BS. The First Crystal Structure of the UP1 Domain of hnRNP A1 Bound to RNA Reveals a New Look for an Old RNA Binding Protein. J Mol Biol 2015; 427:3241-3257. [PMID: 26003924 PMCID: PMC4586317 DOI: 10.1016/j.jmb.2015.05.009] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 04/29/2015] [Accepted: 05/15/2015] [Indexed: 01/01/2023]
Abstract
The heterogeneous nuclear ribonucleoprotein (hnRNP) A1 protein is a multifunctional RNA binding protein implicated in a wide range of biological functions. Mechanisms and putative hnRNP A1-RNA interactions have been inferred primarily from the crystal structure of its UP1 domain bound to ssDNA. RNA stem loops represent an important class of known hnRNP A1 targets, yet little is known about the structural basis of hnRNP A1-RNA recognition. Here, we report the first high-resolution structure (1.92Å) of UP1 bound to a 5'-AGU-3' trinucleotide that resembles sequence elements of several native hnRNP A1-RNA stem loop targets. UP1 interacts specifically with the AG dinucleotide sequence via a "nucleobase pocket" formed by the β-sheet surface of RRM1 and the inter-RRM linker; RRM2 does not contact the RNA. The inter-RRM linker forms the lid of the nucleobase pocket and we show using structure-guided mutagenesis that the conserved salt-bridge interactions (R75:D155 and R88:D157) on the α-helical side of the RNA binding surface stabilize the linker in a geometry poised to bind RNA. We further investigated the structural basis of UP1 binding HIViSL3(ESS3) by determining a structural model of the complex scored by small-angle X-ray scattering. UP1 docks on the apical loop of SL3(ESS3) using its RRM1 domain and inter-RRM linker only. The biophysical implications of the structural model were tested by measuring kinetic binding parameters, where mutations introduced within the apical loop reduce binding affinities by slowing down the rate of complex formation. Collectively, the data presented here provide the first insights into hnRNP A1-RNA interactions.
Collapse
Affiliation(s)
- Christopher E Morgan
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Jennifer L Meagher
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Jeffrey D Levengood
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA
| | - James Delproposto
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Carrie Rollins
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Jeanne A Stuckey
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Blanton S Tolbert
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA.
| |
Collapse
|
28
|
Freiburger L, Sonntag M, Hennig J, Li J, Zou P, Sattler M. Efficient segmental isotope labeling of multi-domain proteins using Sortase A. JOURNAL OF BIOMOLECULAR NMR 2015; 63:1-8. [PMID: 26319988 DOI: 10.1007/s10858-015-9981-0] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 08/24/2015] [Indexed: 06/04/2023]
Abstract
NMR studies of multi-domain protein complexes provide unique insight into their molecular interactions and dynamics in solution. For large proteins domain-selective isotope labeling is desired to reduce signal overlap, but available methods require extensive optimization and often give poor ligation yields. We present an optimized strategy for segmental labeling of multi-domain proteins using the S. aureus transpeptidase Sortase A. Critical improvements compared to existing protocols are (1) the efficient removal of cleaved peptide fragments by centrifugal filtration and (2) a strategic design of cleavable and non-cleavable affinity tags for purification. Our approach enables routine production of milligram amounts of purified segmentally labeled protein for NMR and other biophysical studies.
Collapse
Affiliation(s)
- Lee Freiburger
- Institute of Structural Biology, Helmholtz Zentrum München, 85764, Neuherberg, Germany.
- Center for Integrated Protein Science Munich (CIPSM) at Department of Chemistry, Technische Universität München, Lichtenbergstr.4, 85747, Garching, Germany.
| | - Miriam Sonntag
- Institute of Structural Biology, Helmholtz Zentrum München, 85764, Neuherberg, Germany.
- Center for Integrated Protein Science Munich (CIPSM) at Department of Chemistry, Technische Universität München, Lichtenbergstr.4, 85747, Garching, Germany.
| | - Janosch Hennig
- Institute of Structural Biology, Helmholtz Zentrum München, 85764, Neuherberg, Germany.
- Center for Integrated Protein Science Munich (CIPSM) at Department of Chemistry, Technische Universität München, Lichtenbergstr.4, 85747, Garching, Germany.
| | - Jian Li
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.
| | - Peijian Zou
- Institute of Structural Biology, Helmholtz Zentrum München, 85764, Neuherberg, Germany.
- Center for Integrated Protein Science Munich (CIPSM) at Department of Chemistry, Technische Universität München, Lichtenbergstr.4, 85747, Garching, Germany.
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.
| | - Michael Sattler
- Institute of Structural Biology, Helmholtz Zentrum München, 85764, Neuherberg, Germany.
- Center for Integrated Protein Science Munich (CIPSM) at Department of Chemistry, Technische Universität München, Lichtenbergstr.4, 85747, Garching, Germany.
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.
| |
Collapse
|
29
|
Hennig J, Sattler M. Deciphering the protein-RNA recognition code: Combining large-scale quantitative methods with structural biology. Bioessays 2015; 37:899-908. [DOI: 10.1002/bies.201500033] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Janosch Hennig
- Institute of Structural Biology; Helmholtz Zentrum M; ü; nchen; München Germany
- Department Chemie; Center for Integrated Protein Science Munich at Biomolecular NMR Spectroscopy; Technische Universität München; Garching Germany
| | - Michael Sattler
- Institute of Structural Biology; Helmholtz Zentrum M; ü; nchen; München Germany
- Department Chemie; Center for Integrated Protein Science Munich at Biomolecular NMR Spectroscopy; Technische Universität München; Garching Germany
| |
Collapse
|
30
|
Hennig J, Warner LR, Simon B, Geerlof A, Mackereth CD, Sattler M. Structural Analysis of Protein-RNA Complexes in Solution Using NMR Paramagnetic Relaxation Enhancements. Methods Enzymol 2015; 558:333-362. [PMID: 26068746 DOI: 10.1016/bs.mie.2015.02.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Biological activity in the cell is predominantly mediated by large multiprotein and protein-nucleic acid complexes that act together to ensure functional fidelity. Nuclear magnetic resonance (NMR) spectroscopy is the only method that can provide information for high-resolution three-dimensional structures and the conformational dynamics of these complexes in solution. Mapping of binding interfaces and molecular interactions along with the characterization of conformational dynamics is possible for very large protein complexes. In contrast, de novo structure determination by NMR becomes very time consuming and difficult for protein complexes larger than 30 kDa as data are noisy and sparse. Fortunately, high-resolution structures are often available for individual domains or subunits of a protein complex and thus sparse data can be used to define their arrangement and dynamics within the assembled complex. In these cases, NMR can therefore be efficiently combined with complementary solution techniques, such as small-angle X-ray or neutron scattering, to provide a comprehensive description of the structure and dynamics of protein complexes in solution. Particularly useful are NMR-derived paramagnetic relaxation enhancements (PREs), which provide long-range distance restraints (ca. 20Å) for structural analysis of large complexes and also report on conformational dynamics in solution. Here, we describe the use of PREs from sample production to structure calculation, focusing on protein-RNA complexes. On the basis of recent examples from our own research, we demonstrate the utility, present protocols, and discuss potential pitfalls when using PREs for studying the structure and dynamic features of protein-RNA complexes.
Collapse
Affiliation(s)
- Janosch Hennig
- Institute of Structural Biology, Helmholtz Zentrum München, Oberschleißheim, Germany; Center for Integrated Protein Science Munich at Biomolecular NMR Spectroscopy, Department Chemie, Technische Universität München, Garching, Germany
| | - Lisa R Warner
- Institute of Structural Biology, Helmholtz Zentrum München, Oberschleißheim, Germany; Center for Integrated Protein Science Munich at Biomolecular NMR Spectroscopy, Department Chemie, Technische Universität München, Garching, Germany
| | - Bernd Simon
- European Molecular Biology Laboratory, Heidelberg, Germany
| | - Arie Geerlof
- Institute of Structural Biology, Helmholtz Zentrum München, Oberschleißheim, Germany; Center for Integrated Protein Science Munich at Biomolecular NMR Spectroscopy, Department Chemie, Technische Universität München, Garching, Germany
| | - Cameron D Mackereth
- Institut Européen de Chimie et Biologie, IECB, Univ. Bordeaux, Pessac, France; Inserm, U869, ARNA Laboratory, Bordeaux, France
| | - Michael Sattler
- Institute of Structural Biology, Helmholtz Zentrum München, Oberschleißheim, Germany; Center for Integrated Protein Science Munich at Biomolecular NMR Spectroscopy, Department Chemie, Technische Universität München, Garching, Germany.
| |
Collapse
|
31
|
Small-angle X-ray scattering: a bridge between RNA secondary structures and three-dimensional topological structures. Curr Opin Struct Biol 2015; 30:147-160. [PMID: 25765781 DOI: 10.1016/j.sbi.2015.02.010] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 02/17/2015] [Accepted: 02/18/2015] [Indexed: 11/20/2022]
Abstract
Whereas the structures of small to medium-sized well folded RNA molecules often can be determined by either X-ray crystallography or NMR spectroscopy, obtaining structural information for large RNAs using experimental, computational, or combined approaches remains a major interest and challenge. RNA is very sensitive to small-angle X-ray scattering (SAXS) due to high electron density along phosphate-sugar backbones, whose scattering contribution dominates SAXS intensity. For this reason, SAXS is particularly useful in obtaining global RNA structural information that outlines backbone topologies and, therefore, molecular envelopes. Such information is extremely valuable in bridging the gap between the secondary structures and three-dimensional topological structures of RNA molecules, particularly those that have proven difficult to study using other structure-determination methods. Here we review published results of RNA topological structures derived from SAXS data or in combination with other experimental data, as well as details on RNA sample preparation for SAXS experiments.
Collapse
|
32
|
Chaudhuri BN. Emerging applications of small angle solution scattering in structural biology. Protein Sci 2015; 24:267-76. [PMID: 25516491 PMCID: PMC4353354 DOI: 10.1002/pro.2624] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 12/05/2014] [Indexed: 12/12/2022]
Abstract
Small angle solution X-ray and neutron scattering recently resurfaced as powerful tools to address an array of biological problems including folding, intrinsic disorder, conformational transitions, macromolecular crowding, and self or hetero-assembling of biomacromolecules. In addition, small angle solution scattering complements crystallography, nuclear magnetic resonance spectroscopy, and other structural methods to aid in the structure determinations of multidomain or multicomponent proteins or nucleoprotein assemblies. Neutron scattering with hydrogen/deuterium contrast variation, or X-ray scattering with sucrose contrast variation to a certain extent, is a convenient tool for characterizing the organizations of two-component systems such as a nucleoprotein or a lipid-protein assembly. Time-resolved small and wide-angle solution scattering to study biological processes in real time, and the use of localized heavy-atom labeling and anomalous solution scattering for applications as FRET-like molecular rulers, are amongst promising newer developments. Despite the challenges in data analysis and interpretation, these X-ray/neutron solution scattering based approaches hold great promise for understanding a wide variety of complex processes prevalent in the biological milieu.
Collapse
Affiliation(s)
- Barnali N Chaudhuri
- Faculty of Life Sciences and Biotechnology, South Asian UniversityAkbar Bhawan, Chanakyapuri, New Delhi, India
| |
Collapse
|
33
|
Yang S. Methods for SAXS-based structure determination of biomolecular complexes. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2014; 26:7902-10. [PMID: 24888261 PMCID: PMC4285438 DOI: 10.1002/adma.201304475] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Revised: 03/10/2014] [Indexed: 05/20/2023]
Abstract
Measurements from small-angle X-ray scattering (SAXS) are highly informative to determine the structures of bimolecular complexes in solution. Here, current and recent SAXS-driven developments are described, with an emphasis on computational modeling. In particular, accurate methods to computing one theoretical scattering profile from a given structure model are discussed, with a key focus on structure factor coarse-graining and hydration contribution. Methods for reconstructing topological structures from an experimental SAXS profile are currently under active development. We report on several modeling tools designed for conformation generation that make use of either atomic-level or coarse-grained representations. Furthermore, since large, flexible biomolecules can adopt multiple well-defined conformations, a traditional single-conformation SAXS analysis is inappropriate, so we also discuss recent methods that utilize the concept of ensemble optimization, weighing in on the SAXS contributions of a heterogeneous mixture of conformations. These tools will ultimately posit the usefulness of SAXS data beyond a simple space-filling approach by providing a reliable structure characterization of biomolecular complexes under physiological conditions.
Collapse
Affiliation(s)
- Sichun Yang
- Center for Proteomics and Department of Pharmacology, Department of Physiology and Biophysics, Case Western Reserve University, 10900 Euclid Ave, Cleveland, OH 44106-4988, USA
| |
Collapse
|
34
|
Hennig J, Militti C, Popowicz GM, Wang I, Sonntag M, Geerlof A, Gabel F, Gebauer F, Sattler M. Structural basis for the assembly of the Sxl–Unr translation regulatory complex. Nature 2014; 515:287-90. [DOI: 10.1038/nature13693] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Accepted: 07/16/2014] [Indexed: 01/16/2023]
|
35
|
Kirby NM, Cowieson NP. Time-resolved studies of dynamic biomolecules using small angle X-ray scattering. Curr Opin Struct Biol 2014; 28:41-6. [PMID: 25108308 DOI: 10.1016/j.sbi.2014.07.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Revised: 07/10/2014] [Accepted: 07/18/2014] [Indexed: 12/30/2022]
Abstract
Small angle X-ray scattering (SAXS) of biomacromolecules in solution has become a prominent technique in structural biology. Whilst the majority of current use is for static measurements, the field is also advancing for measurements where the sample at the beam position changes with time, using high throughput systems, chromatography, high speed mixing and pump-probe techniques in particular. Time resolved work is greatly aided by increasingly sophisticated software for acquiring and analysing data, together with developments in X-ray sources, beamline optics and detectors. The exploitation of spatial coherence is under development, with X-ray free electron lasers aiming to provide major advances in single molecule structure reconstruction and time resolution. Here we provide an overview of current developments advancing time resolved solution SAXS.
Collapse
Affiliation(s)
- Nigel M Kirby
- Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168, Australia.
| | - Nathan P Cowieson
- Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168, Australia
| |
Collapse
|
36
|
Göbl C, Madl T, Simon B, Sattler M. NMR approaches for structural analysis of multidomain proteins and complexes in solution. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2014; 80:26-63. [PMID: 24924266 DOI: 10.1016/j.pnmrs.2014.05.003] [Citation(s) in RCA: 130] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 05/14/2014] [Indexed: 05/22/2023]
Abstract
NMR spectroscopy is a key method for studying the structure and dynamics of (large) multidomain proteins and complexes in solution. It plays a unique role in integrated structural biology approaches as especially information about conformational dynamics can be readily obtained at residue resolution. Here, we review NMR techniques for such studies focusing on state-of-the-art tools and practical aspects. An efficient approach for determining the quaternary structure of multidomain complexes starts from the structures of individual domains or subunits. The arrangement of the domains/subunits within the complex is then defined based on NMR measurements that provide information about the domain interfaces combined with (long-range) distance and orientational restraints. Aspects discussed include sample preparation, specific isotope labeling and spin labeling; determination of binding interfaces and domain/subunit arrangements from chemical shift perturbations (CSP), nuclear Overhauser effects (NOEs), isotope editing/filtering, cross-saturation, and differential line broadening; and based on paramagnetic relaxation enhancements (PRE) using covalent and soluble spin labels. Finally, the utility of complementary methods such as small-angle X-ray or neutron scattering (SAXS, SANS), electron paramagnetic resonance (EPR) or fluorescence spectroscopy techniques is discussed. The applications of NMR techniques are illustrated with studies of challenging (high molecular weight) protein complexes.
Collapse
Affiliation(s)
- Christoph Göbl
- Biomolecular NMR and Center for Integrated Protein Science Munich at Department Chemie, Technische Universität München, Garching, Germany
| | - Tobias Madl
- Biomolecular NMR and Center for Integrated Protein Science Munich at Department Chemie, Technische Universität München, Garching, Germany; Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany; Institute of Molecular Biology, University of Graz, Graz, Austria.
| | - Bernd Simon
- European Molecular Biology Laboratory, Structural and Computational Biology Unit, Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Michael Sattler
- Biomolecular NMR and Center for Integrated Protein Science Munich at Department Chemie, Technische Universität München, Garching, Germany; Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany.
| |
Collapse
|
37
|
Hennig J, Sattler M. The dynamic duo: combining NMR and small angle scattering in structural biology. Protein Sci 2014; 23:669-82. [PMID: 24687405 DOI: 10.1002/pro.2467] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 03/25/2014] [Accepted: 03/28/2014] [Indexed: 12/12/2022]
Abstract
Structural biology provides essential information for elucidating molecular mechanisms that underlie biological function. Advances in hardware, sample preparation, experimental methods, and computational approaches now enable structural analysis of protein complexes with increasing complexity that more closely represent biologically entities in the cellular environment. Integrated multidisciplinary approaches are required to overcome limitations of individual methods and take advantage of complementary aspects provided by different structural biology techniques. Although X-ray crystallography remains the method of choice for structural analysis of large complexes, crystallization of flexible systems is often difficult and does typically not provide insights into conformational dynamics present in solution. Nuclear magnetic resonance spectroscopy (NMR) is well-suited to study dynamics at picosecond to second time scales, and to map binding interfaces even of large systems at residue resolution but suffers from poor sensitivity with increasing molecular weight. Small angle scattering (SAS) methods provide low resolution information in solution and can characterize dynamics and conformational equilibria complementary to crystallography and NMR. The combination of NMR, crystallography, and SAS is, thus, very useful for analysis of the structure and conformational dynamics of (large) protein complexes in solution. In high molecular weight systems, where NMR data are often sparse, SAS provides additional structural information and can differentiate between NMR-derived models. Scattering data can also validate the solution conformation of a crystal structure and indicate the presence of conformational equilibria. Here, we review current state-of-the-art approaches for combining NMR, crystallography, and SAS data to characterize protein complexes in solution.
Collapse
Affiliation(s)
- Janosch Hennig
- Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstr.1, D-85764, Neuherberg, Germany; Center for Integrated Protein Science Munich at Chair Biomolecular NMR Spectroscopy, Department Chemie, Technische Universität München, Lichtenbergstr. 4, D-85747, Garching, Germany
| | | |
Collapse
|
38
|
Carlomagno T. Present and future of NMR for RNA-protein complexes: a perspective of integrated structural biology. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2014; 241:126-136. [PMID: 24656085 DOI: 10.1016/j.jmr.2013.10.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Revised: 10/14/2013] [Accepted: 10/16/2013] [Indexed: 06/03/2023]
Abstract
Nucleic acids are gaining enormous importance as key molecules in almost all biological processes. Most nucleic acids do not act in isolation but are generally associated with proteins to form high-molecular-weight nucleoprotein complexes. In this perspective article I focus on the structural studies of supra-molecular ribonucleoprotein (RNP) assemblies in solution by a combination of state-of-the-art TROSY-based NMR experiments and other structural biology techniques. I discuss ways how to combine sparse NMR data with low-resolution structural information from small-angle scattering, fluorescence and electron paramagnetic resonance spectroscopy to obtain the structure of large RNP particles by an integrated structural biology approach. In the last section I give a perspective for the study of RNP complexes by solid-state NMR.
Collapse
Affiliation(s)
- Teresa Carlomagno
- European Molecular Biology Laboratory, Structural and Computational Biology Unit, Meyerhofstrasse 1, D-69117 Heidelberg, Germany.
| |
Collapse
|
39
|
van Ingen H, Bonvin AMJJ. Information-driven modeling of large macromolecular assemblies using NMR data. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2014; 241:103-114. [PMID: 24656083 DOI: 10.1016/j.jmr.2013.10.021] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Accepted: 10/25/2013] [Indexed: 06/03/2023]
Abstract
Availability of high-resolution atomic structures is one of the prerequisites for a mechanistic understanding of biomolecular function. This atomic information can, however, be difficult to acquire for interesting systems such as high molecular weight and multi-subunit complexes. For these, low-resolution and/or sparse data from a variety of sources including NMR are often available to define the interaction between the subunits. To make best use of all the available information and shed light on these challenging systems, integrative computational tools are required that can judiciously combine and accurately translate the sparse experimental data into structural information. In this Perspective we discuss NMR techniques and data sources available for the modeling of large and multi-subunit complexes. Recent developments are illustrated by particularly challenging application examples taken from the literature. Within this context, we also position our data-driven docking approach, HADDOCK, which can integrate a variety of information sources to drive the modeling of biomolecular complexes. It is the synergy between experimentation and computational modeling that will provides us with detailed views on the machinery of life and lead to a mechanistic understanding of biomolecular function.
Collapse
Affiliation(s)
- Hugo van Ingen
- NMR Spectroscopy Research Group, Bijvoet Center for Biomolecular Research, Utrecht University, Faculty of Science - Chemistry, Padulaan 8, 3854 CH Utrecht, The Netherlands.
| | - Alexandre M J J Bonvin
- NMR Spectroscopy Research Group, Bijvoet Center for Biomolecular Research, Utrecht University, Faculty of Science - Chemistry, Padulaan 8, 3854 CH Utrecht, The Netherlands.
| |
Collapse
|
40
|
Schwede T. Protein modeling: what happened to the "protein structure gap"? Structure 2014; 21:1531-40. [PMID: 24010712 DOI: 10.1016/j.str.2013.08.007] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Revised: 08/12/2013] [Accepted: 08/12/2013] [Indexed: 11/27/2022]
Abstract
Computational modeling of three-dimensional macromolecular structures and complexes from their sequence has been a long-standing vision in structural biology. Over the last 2 decades, a paradigm shift has occurred: starting from a large "structure knowledge gap" between the huge number of protein sequences and small number of known structures, today, some form of structural information, either experimental or template-based models, is available for the majority of amino acids encoded by common model organism genomes. With the scientific focus of interest moving toward larger macromolecular complexes and dynamic networks of interactions, the integration of computational modeling methods with low-resolution experimental techniques allows the study of large and complex molecular machines. One of the open challenges for computational modeling and prediction techniques is to convey the underlying assumptions, as well as the expected accuracy and structural variability of a specific model, which is crucial to understanding its limitations.
Collapse
Affiliation(s)
- Torsten Schwede
- Biozentrum, University of Basel, Klingelbergstrasse 50-70, 4056 Basel, Switzerland; Computational Structural Biology, SIB Swiss Institute of Bioinformatics, Klingelbergstrasse 50-70, 4056 Basel, Switzerland.
| |
Collapse
|
41
|
Rodrigues JPGLM, Bonvin AMJJ. Integrative computational modeling of protein interactions. FEBS J 2014; 281:1988-2003. [DOI: 10.1111/febs.12771] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 01/03/2014] [Accepted: 02/19/2014] [Indexed: 01/09/2023]
Affiliation(s)
- João P. G. L. M. Rodrigues
- Computational Structural Biology Group; Bijvoet Center for Biomolecular Research; Utrecht University; the Netherlands
| | - Alexandre M. J. J. Bonvin
- Computational Structural Biology Group; Bijvoet Center for Biomolecular Research; Utrecht University; the Netherlands
| |
Collapse
|
42
|
Kobayashi A, Kanaba T, Satoh R, Fujiwara T, Ito Y, Sugiura R, Mishima M. Structure of the second RRM domain of Nrd1, a fission yeast MAPK target RNA binding protein, and implication for its RNA recognition and regulation. Biochem Biophys Res Commun 2013; 437:12-7. [DOI: 10.1016/j.bbrc.2013.06.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2013] [Accepted: 06/03/2013] [Indexed: 12/13/2022]
|
43
|
|